You searched for subject:(Lignocellulose).
Showing records 1 – 30 of
251 total matches.
◁ [1] [2] [3] [4] [5] [6] [7] [8] [9] ▶
University of Georgia
1.
Brandon, Sarah Katherine.
Development and optimization of pressurized batch hot water pretreatment and comparison of warm season grasses for bioconversion to ethanol.
Degree: MS, Microbiology, 2008, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/brandon_sarah_k_200812_ms 
► Efficient conversion of lignocellulosic biomass to ethanol is required to make the overall process more economically feasible. Developing new and more effective pretreatments to disrupt…
(more)
▼ Efficient conversion of lignocellulosic biomass to ethanol is required to make the overall process more economically feasible. Developing new and more effective pretreatments to disrupt lignocellulosic biomass prior to enzymatic saccharification and fermentation is one approach to meet this end. A pressurized batch hot water (PBHW) reactor was designed and tested as an autohydrolytic pretreatment for grass biomass. Pretreatment of whole biomass solids at 230° for two minutes was found to be the optimal operating parameters for the pretreatment to disrupt the biomass and remove hemicellulose. Pressure and solids loading during pretreatment had neglible effects on pretreatment efficacy. Tifton 85 bermudagrass, GA 993 switchgrass, and Merkeron napiergrass were evaluated for bioconversion to ethanol using PBHW pretreatment, with napiergrass producing the highest ethanol yield of 22.45 g/L. Inhibitors were also evaluated during the bioconversion process, and PBHW pretreatment results in removal of fermentation and enzyme inhibitors prior to fermentation.
Advisors/Committee Members: Joy B. Doran-Peterson.
Subjects/Keywords: lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Brandon, S. K. (2008). Development and optimization of pressurized batch hot water pretreatment and comparison of warm season grasses for bioconversion to ethanol. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/brandon_sarah_k_200812_ms
Chicago Manual of Style (16th Edition):
Brandon, Sarah Katherine. “Development and optimization of pressurized batch hot water pretreatment and comparison of warm season grasses for bioconversion to ethanol.” 2008. Masters Thesis, University of Georgia. Accessed January 19, 2020.
http://purl.galileo.usg.edu/uga_etd/brandon_sarah_k_200812_ms.
MLA Handbook (7th Edition):
Brandon, Sarah Katherine. “Development and optimization of pressurized batch hot water pretreatment and comparison of warm season grasses for bioconversion to ethanol.” 2008. Web. 19 Jan 2020.
Vancouver:
Brandon SK. Development and optimization of pressurized batch hot water pretreatment and comparison of warm season grasses for bioconversion to ethanol. [Internet] [Masters thesis]. University of Georgia; 2008. [cited 2020 Jan 19].
Available from: http://purl.galileo.usg.edu/uga_etd/brandon_sarah_k_200812_ms.
Council of Science Editors:
Brandon SK. Development and optimization of pressurized batch hot water pretreatment and comparison of warm season grasses for bioconversion to ethanol. [Masters Thesis]. University of Georgia; 2008. Available from: http://purl.galileo.usg.edu/uga_etd/brandon_sarah_k_200812_ms
Rhodes University
2.
Van Dyk, Jacoba Susanna.
Characterisation of the cellulolytic and hemicellulolytic system of Bacillus Licheniformis SVD1 and the isolation and characterisation of a multi-enzyme complex.
Degree: Faculty of Science, Biochemistry, Microbiology and Biotechnology, 2009, Rhodes University
URL: http://hdl.handle.net/10962/d1003995
► The biological degradation of lignocellulose into fermentable sugars for the production of liquid transportation fuels is feasible and sustainable, but equires a variety of enzymes…
(more)
▼ The biological degradation of lignocellulose into fermentable sugars for the production of liquid transportation fuels is feasible and sustainable, but equires a variety of enzymes working in synergy as lignocellulose is a complex and recalcitrant substrate. The cellulosome is a multi-enzyme complex (MEC) with a variety of cellulolytic and hemicellulolytic enzymes that appears to facilitate an enhanced synergy and efficiency, as compared to free enzymes, for the degradation of recalcitrant substrates such as lignocellulose and plant cell walls. Most of the studies on cellulosomes have focused on a few organisms; C. thermocellum, C. cellulovorans and C. cellulolyticum, and there is only limited knowledge vailable on similar complexes in other organisms. Some MECs have been identified in aerobic bacteria such as Bacillus circulans and Paenibacillus curdlanolyticus, but the nature of these MECs have not been fully elucidated. This study investigated the cellulolytic and emi-cellulolytic system of Bacillus licheniformis SVD1 with specific reference to the presence of a MEC, which has never been reported in the literature for B. licheniformis. A MEC of approximately 2,000 kDa in size, based on size exclusion chromatography using Sepharose 4B, was purified from a culture of B. licheniformis. When investigating the presence of enzyme activity in the total crude fraction as well as the MEC of a birchwood xylan culture, B. licheniformis was found to display a variety of enzyme activities on a range of substrates, although xylanases were by far the predominant enzyme activity present in both the crude and MEC fractions. Based on zymogram analysis there were three CMCases, seven xylanases, three mannanases and two pectinases in the crude fraction, while the MEC had two CMCases, seven xylanases, two mannanases and one pectinase. The pectinases in the crude could be identified as a pectin methyl esterase and a lyase, while the methyl esterase was absent in the MEC. Seventeen protein species could be detected in the MEC but only nine of these displayed activity on the substrates tested. The possible presence of a β-xylosidase in the crude fraction was deduced from thin layer chromatography (TLC) which demonstrated the production of xylose by the crude fraction. It was furthermore established that B. licheniformis SVD1 was able to regulate levels of enzyme expression based on the substrate the organism was cultured on. It was found that complexed xylanase activity had a pH optimum of between pH 6.0 and 7.0 and a temperature optimum of 55 °C. Complexed xylanase activity was found to be slightly inhibited by CaCl2 and inhibited to a greater extent by EDTA. Complexed xylanase activity was further shown to be activated in the presence of xylose and xylobiose, both compounds which are products of enzymatic degradation. Ethanol was found to inhibit complexed xylanase activity. The kinetic parameters for complexed xylanase activity were measured and the Km value was calculated as 2.84 mg/ml while the maximal velocity (Vmax) was calculated…
Subjects/Keywords: Lignocellulose; Lignocellulose – Biotechnology; Lignocellulose – Biodegradation; Plant biotechnology
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Van Dyk, J. S. (2009). Characterisation of the cellulolytic and hemicellulolytic system of Bacillus Licheniformis SVD1 and the isolation and characterisation of a multi-enzyme complex. (Thesis). Rhodes University. Retrieved from http://hdl.handle.net/10962/d1003995
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Van Dyk, Jacoba Susanna. “Characterisation of the cellulolytic and hemicellulolytic system of Bacillus Licheniformis SVD1 and the isolation and characterisation of a multi-enzyme complex.” 2009. Thesis, Rhodes University. Accessed January 19, 2020.
http://hdl.handle.net/10962/d1003995.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Van Dyk, Jacoba Susanna. “Characterisation of the cellulolytic and hemicellulolytic system of Bacillus Licheniformis SVD1 and the isolation and characterisation of a multi-enzyme complex.” 2009. Web. 19 Jan 2020.
Vancouver:
Van Dyk JS. Characterisation of the cellulolytic and hemicellulolytic system of Bacillus Licheniformis SVD1 and the isolation and characterisation of a multi-enzyme complex. [Internet] [Thesis]. Rhodes University; 2009. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/10962/d1003995.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Van Dyk JS. Characterisation of the cellulolytic and hemicellulolytic system of Bacillus Licheniformis SVD1 and the isolation and characterisation of a multi-enzyme complex. [Thesis]. Rhodes University; 2009. Available from: http://hdl.handle.net/10962/d1003995
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Oregon State University
3.
Fenske, John J.
Utilization of lignocellulosic polysaccharides.
Degree: PhD, Food Science and Technology, 1998, Oregon State University
URL: http://hdl.handle.net/1957/27269
► Lignocellulosic biomass represents a vast supply of fermentable carbohydrates and functional aromatic compounds. Conversion of lignocellulosics to ethanol and other useful products would be of…
(more)
▼ Lignocellulosic biomass represents a vast supply of fermentable carbohydrates
and functional aromatic compounds. Conversion of lignocellulosics to ethanol and other
useful products would be of widespread economical and environmental benefit. Better
understanding of the behavior of different lignicellulosic feedstocks in fermentation
protocols as well as catalytic activities involved in lignocellulosic depolymerization will
further enhance the commercial viability of biomass-to-ethanol conversion processes.
The relative toxicity of the combined non-xylose components in prehydrolysates
derived from three different lignocellulosic biomass feedstocks (poplar, corn stover and
switchgrass, or Panicum virgatum L.) was determined using a Pichia stipits fermentation
assay. The relative toxicity of the prehydrolysates, in decreasing order, was poplar-derived
prehydrolysates > switchgrass-derived prehydrolysates > corn stover-derived
prehydrolysates. Ethanol yields averaged 74%, 83% and 88% of control values for
poplar, switchgrass and corn stover prehydrolysates, respectively. Volumetric ethanol
productivities (g ethanol l⁻¹ h⁻¹) averaged 32%, 70% and 102% of control values for
poplar, switchgrass and corn stover prehydrolysates, respectively. Ethanol productivities
correlated closely with acetate concentrations in the prehydrolysates; however, regression lines correlating acetate concentrations and ethanol productivities were found to be
feedstock-dependent.
Differences in the relative toxicity of xylose-rich prehydrolysates derived from
woody and herbaceous feedstocks are likely due to the relative abundance of a variety of
inhibitory compounds, e.g. acetate and aromatic comounds. Fourteen aromatic monomers
present in prehydrolysates prepared from corn stover, switchgrass, and poplar were
tentatively identified by comparison with published mass spectra. The concentrations of
the aromatic monomers totaled 112, 141 and 247 mg(l)⁻¹ for corn stover, switchgrass and
poplar prehydrolysates, respectively. The woody and herbaceous feedstocks differed in
both amount and type of aromatic monomers.
The cellulases of Trichoderma reesei are the most widely studied for use in the
depolymerization of lignocellulosics. The Trichoderma cellobiohydrolases CBH1 and
CBH2 are traditionally categorized as exo-acting cellulases. A simple individual-based
model was created to explore the potential effects of native endo activity on substratevelocity
profiles. The model results indicate that an enzyme with a small amount of endo
activity will show an apparent substrate inhibition as substrate levels are increased.
Actual hydrolysis studies using affinity chromatography-purified CBH2 preparations
from three laboratories indicate that CBH2 has native endo activity, while CBH1 does
not.
Advisors/Committee Members: Penner, Michael H. (advisor), Bakalinsky, Alan Tagore (committee member).
Subjects/Keywords: Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fenske, J. J. (1998). Utilization of lignocellulosic polysaccharides. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/27269
Chicago Manual of Style (16th Edition):
Fenske, John J. “Utilization of lignocellulosic polysaccharides.” 1998. Doctoral Dissertation, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/27269.
MLA Handbook (7th Edition):
Fenske, John J. “Utilization of lignocellulosic polysaccharides.” 1998. Web. 19 Jan 2020.
Vancouver:
Fenske JJ. Utilization of lignocellulosic polysaccharides. [Internet] [Doctoral dissertation]. Oregon State University; 1998. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/27269.
Council of Science Editors:
Fenske JJ. Utilization of lignocellulosic polysaccharides. [Doctoral Dissertation]. Oregon State University; 1998. Available from: http://hdl.handle.net/1957/27269
Oregon State University
4.
Meunier-Goddik, Lisbeth.
Conversion of lignocellulosic biomass : analysis of substrate characteristics.
Degree: PhD, Food Science and Technology, 1998, Oregon State University
URL: http://hdl.handle.net/1957/26187
► The objective of this research was to investigate the influence of physicochemical properties of lignocellulosic biomass on the rate and extent of cellulose conversion, i.e.…
(more)
▼ The objective of this research was to investigate the influence of physicochemical
properties of lignocellulosic biomass on the rate and extent of cellulose conversion, i.e.
the "hydrolyzability" of the substrate.
The initial two parts of this thesis investigated the interactions between various
components of pretreated biomass. The relevance of cellulase partitioning between the
cellulose and non-cellulose components of pretreated switchgrass was determined.
Furthermore, a method was developed to assess the changes in surface area of the non-cellulose
fraction during saccharification. The overall conclusion from these studies was
that for an optimally pretreated switchgrass sample the cellulose and non-cellulose
components are fully disassociated and the non-cellulose fraction does not appear to
interfere with cellulose conversion.
The third study determined the changes in physicochemical properties of native
and pretreated poplar during simultaneous saccharification and fermentation (SSF).
While this study gave an unprecedented insight into the dynamics of SSF, it was also
apparent that parameters measuring the complete feedstock are inadequate for explaining
cellulose reactivity/hydrolyzability during saccharification.
As a consequence of these conclusions, the final study focused on properties of
model celluloses and initial rates of hydrolysis by the major cellulase - CBHI. The
content of insoluble ends was measured by different modified soluble reducing sugar
assays and by tritium labeling through NaB³H₄ reduction reactions. The content of
insoluble reducing ends partially explained the relative initial rates of hydrolysis. However, comparisons between celluloses in their crystalline and corresponding
amorphous state revealed that crystallinity also accounts for some of the observed rate
differences. Furthermore, surface characteristics, such as the presence of pores, must be
considered to fully explain cellulose reactivity.
Advisors/Committee Members: Penner, Michael H. (advisor).
Subjects/Keywords: Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Meunier-Goddik, L. (1998). Conversion of lignocellulosic biomass : analysis of substrate characteristics. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/26187
Chicago Manual of Style (16th Edition):
Meunier-Goddik, Lisbeth. “Conversion of lignocellulosic biomass : analysis of substrate characteristics.” 1998. Doctoral Dissertation, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/26187.
MLA Handbook (7th Edition):
Meunier-Goddik, Lisbeth. “Conversion of lignocellulosic biomass : analysis of substrate characteristics.” 1998. Web. 19 Jan 2020.
Vancouver:
Meunier-Goddik L. Conversion of lignocellulosic biomass : analysis of substrate characteristics. [Internet] [Doctoral dissertation]. Oregon State University; 1998. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/26187.
Council of Science Editors:
Meunier-Goddik L. Conversion of lignocellulosic biomass : analysis of substrate characteristics. [Doctoral Dissertation]. Oregon State University; 1998. Available from: http://hdl.handle.net/1957/26187
Oregon State University
5.
Esteghlalian, Alireza.
Modeling and optimization of the dilute-sulfuric acid pretreatment of lignocellulosic.
Degree: PhD, Bioresource Engineering, 1996, Oregon State University
URL: http://hdl.handle.net/1957/34308
► Environmental concerns about urban air quality, global climate change, energy security and economic considerations motivate a growing interest in alternative fuels for the transportation sector.…
(more)
▼ Environmental concerns about urban air quality, global climate change, energy
security and economic considerations motivate a growing interest in alternative fuels for
the transportation sector. Ethanol, a fermentation-derived fuel, can be produced by
bioconversion of renewable materials, such as wood, grass, and waste. Combustion of
ethanol fuel, in both neat and blended form, can improve the engine efficiency, and lower
the emission of CO, NO[subscript x], and volatile organic compounds (VOC), hence reducing the
urban ozone level. Moreover, enhanced agricultural activities for production and
collection of lignocellulosic feedstocks and industrial developments for production of
ethanol will help the economic growth by creating new jobs and new income sources.
Bioconversion of lignocellulosic feedstocks into ethanol requires a pretreatment process to
increase the digestibility of cellulose by cellulolytic enzymes. The dilute-sulfuric acid
pretreatment can hydrolyze hemicelluloses (xylan), disrupt lignin structure, and increase
the yield of ethanol production from fermentation of monomeric units of cellulose
(glucose). In this study, herbaceous (corn stover and switchgrass) and woody (poplar
chips) feedstocks were pretreated with dilute sulfuric acid (0.6, 0.9, and 1.2% w/w) in a
batch reactor at relatively high temperatures (140, 160 and 180°C). A unifying kinetic
model including reaction time, temperature and acid concentration was developed, and
pertinent kinetic parameters were determined. This model can predict the percentages of
xylan remaining in the pretreated solids, net xylose yield in the liquid prehydrolysate, and
xylose loss after pretreatment of a feedstock at a certain set of reaction conditions. Using
this model, four optimum reaction conditions for obtaining maximum net xylose yield in
the liquid prehydrolysate were identified. The yield and rate of ethanol production from
the optimum prehydrolysates by the pentose fermenting yeast, Pichia stipitis, were
determined. It was found that pretreating the selected feedstocks at 170-180°C with 1.0-1.2% sulfuric acid for 1-3 min resulted in the recovery of 80-85% of the original xylan in
the liquid prehyrolysate. It was also found that feedstocks with higher neutralizing
capacity (e.g., corn stover) produced lower sugar yields as a result of acid neutralization.
Pretreatment of feedstocks at conditions beyond the optimum reaction conditions would
increase the extent of xylose degradation, and lower the yield and rate of ethanol
production due to loss of fermentable sugars and formation of toxic byproducts. The
optimum prehydrolysates of corn stover produced the highest yields of ethanol (0.39-0.47
g ethanol/g xylose) followed by switchgrass (0.36-0.45) and poplar (0.26-0.44). The
inhibitory effects of byproducts (e.g., acetate) was more pronounced in poplar
prehydrolysates.
Advisors/Committee Members: Hashimoto, Andrew G. (advisor), Bothwell, Michelle (committee member).
Subjects/Keywords: Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Esteghlalian, A. (1996). Modeling and optimization of the dilute-sulfuric acid pretreatment of lignocellulosic. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/34308
Chicago Manual of Style (16th Edition):
Esteghlalian, Alireza. “Modeling and optimization of the dilute-sulfuric acid pretreatment of lignocellulosic.” 1996. Doctoral Dissertation, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/34308.
MLA Handbook (7th Edition):
Esteghlalian, Alireza. “Modeling and optimization of the dilute-sulfuric acid pretreatment of lignocellulosic.” 1996. Web. 19 Jan 2020.
Vancouver:
Esteghlalian A. Modeling and optimization of the dilute-sulfuric acid pretreatment of lignocellulosic. [Internet] [Doctoral dissertation]. Oregon State University; 1996. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/34308.
Council of Science Editors:
Esteghlalian A. Modeling and optimization of the dilute-sulfuric acid pretreatment of lignocellulosic. [Doctoral Dissertation]. Oregon State University; 1996. Available from: http://hdl.handle.net/1957/34308
Ryerson University
7.
Amin, Zeid.
Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production.
Degree: 2017, Ryerson University
URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A7117
► Lignocellulosic substrate is a resource that contains a locked energy reserve that is normally lost during anaerobic digestion. Lignocellulosic substrate is one of the most…
(more)
▼ Lignocellulosic substrate is a resource that contains a locked energy reserve that is normally lost during anaerobic digestion. Lignocellulosic substrate is one of the most abundant sources of organic matter available and yet its energy recovery has much room for improvement. Lignocellulosic substrate has cellular properties that are deemed extremely difficult to degrade due to complexity which is why this energy reserve is never unlocked during anaerobic digestion. There are several successful pretreatment methods that are used to degrade this lignocellulosic substrate and unlock this energy reserve. This paper will focus on the methods that include mechanical, irradiation, chemical and combined pretreatment processes. Analysis is conducted on all the studies that are obtained to compare the successes of the different types of pretreatment processes used. Each of the different listed pretreatment processes have different energy requirements, treatment times, and solvent requirement and are acting to enhancing methane production. The improvement in methane production varies from process to process and study to study creating a need to compile all of this valuable data into this research report. This will help future researchers in navigating the available studies of pretreatment of lignocellulosic substrate for improving methane production.
Subjects/Keywords: Lignocellulose – Biotechnology; Biodegradation; Methane; Lignocellulose – Biodegradation
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Amin, Z. (2017). Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A7117
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Amin, Zeid. “Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production.” 2017. Thesis, Ryerson University. Accessed January 19, 2020.
https://digital.library.ryerson.ca/islandora/object/RULA%3A7117.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Amin, Zeid. “Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production.” 2017. Web. 19 Jan 2020.
Vancouver:
Amin Z. Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production. [Internet] [Thesis]. Ryerson University; 2017. [cited 2020 Jan 19].
Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A7117.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Amin Z. Evaluation Of Mechanical, Irradiation And Chemical Pretreatment Lignocelulosic Substrate For Enhanced Methane Production. [Thesis]. Ryerson University; 2017. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A7117
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Ontario Institute of Technology
8.
Ng, Sita.
Pure culture and metagenomic approaches to investigate cellulose and xylan degradation.
Degree: 2010, University of Ontario Institute of Technology
URL: http://hdl.handle.net/10155/89
► Lignocellulose is composed of lignin, hemicellulose, and cellulose. Lignocellulose waste is a sustainable and renewable resource available for use in biotechnological applications. Efficient enzyme production…
(more)
▼ Lignocellulose is composed of lignin, hemicellulose, and cellulose.
Lignocellulose waste is a sustainable and renewable resource available for use in biotechnological applications. Efficient enzyme production and enzymes with high catalytic activity are needed for the use of
lignocellulose. The study of cellulases and xylanases that degrade cellulose and xylan into constituent monosaccharides is required to advance industrial application of these enzymes. The use of a traditional pure culture approach to discover and characterize cellulases and xylanases from novel actinomycete isolates and the use of metagenomics to uncover previously unidentified cellulase genes was undertaken. Actinomycetes were cultivated from soil samples and the isolate with the best cellulase and xylanase activity was subjected to strain improvement through protoplast fusion. Enhanced enzymatic activity was found in one fusant. Differential release of sugars from xylan was observed through gas chromatographic analysis between the parental and fusant cultures. Genome shuffling was observed in 16S rRNA genes after protoplast fusion. Finally, one putative endo-??-1,4-glucanase was discovered in a metagenomic library created from cellulose-enriched potting soil.
Advisors/Committee Members: Strap, Janice, Bonetta, Dario.
Subjects/Keywords: Lignocellulose; Cellulase; Xylanase; Metagenomics; Actinomycete
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ng, S. (2010). Pure culture and metagenomic approaches to investigate cellulose and xylan degradation. (Thesis). University of Ontario Institute of Technology. Retrieved from http://hdl.handle.net/10155/89
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ng, Sita. “Pure culture and metagenomic approaches to investigate cellulose and xylan degradation.” 2010. Thesis, University of Ontario Institute of Technology. Accessed January 19, 2020.
http://hdl.handle.net/10155/89.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ng, Sita. “Pure culture and metagenomic approaches to investigate cellulose and xylan degradation.” 2010. Web. 19 Jan 2020.
Vancouver:
Ng S. Pure culture and metagenomic approaches to investigate cellulose and xylan degradation. [Internet] [Thesis]. University of Ontario Institute of Technology; 2010. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/10155/89.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ng S. Pure culture and metagenomic approaches to investigate cellulose and xylan degradation. [Thesis]. University of Ontario Institute of Technology; 2010. Available from: http://hdl.handle.net/10155/89
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Aberdeen
9.
Zahedifar, Mojtaba.
Novel uses of lignin and hemicellulosic sugars from acid-hydrolysed lignocellulosic materials.
Degree: PhD, 1996, University of Aberdeen
URL: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=195786
;
http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342205
► Lignocellulosic materials (LM) are an ever present renewable and available energy source. The energy stored by photosynthesis in the form of vegetation is about ten…
(more)
▼ Lignocellulosic materials (LM) are an ever present renewable and available energy source. The energy stored by photosynthesis in the form of vegetation is about ten times more than world's annual energy consumption (Zsuffa, 1982). This source is the only alternative for chemical production after fossil fuels. Formation of organic acids (mainly acetic acid) from hemicellulose during steam treatment of LM leads to acid hydrolysis of cell wall components. Solubilization of hemicellulose and depolymerization of lignin are the most important changes that occur during the process. During hydrolysis of LM appreciable amounts of sugar degradation products, organic acids and phenolics are produced. Inhibitory effects of the compounds on yeast during alcoholic fermentation have been reported and several methods have been proposed to overcome the problem. Among the new compounds phenolics derived from lignin depolymerization have received most attention. Another problem during enzymic saccharification of cellulose is partial inactivation of cell free enzymes. The above mentioned constraints were investigated in this study.
Subjects/Keywords: 572.8; Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zahedifar, M. (1996). Novel uses of lignin and hemicellulosic sugars from acid-hydrolysed lignocellulosic materials. (Doctoral Dissertation). University of Aberdeen. Retrieved from http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=195786 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342205
Chicago Manual of Style (16th Edition):
Zahedifar, Mojtaba. “Novel uses of lignin and hemicellulosic sugars from acid-hydrolysed lignocellulosic materials.” 1996. Doctoral Dissertation, University of Aberdeen. Accessed January 19, 2020.
http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=195786 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342205.
MLA Handbook (7th Edition):
Zahedifar, Mojtaba. “Novel uses of lignin and hemicellulosic sugars from acid-hydrolysed lignocellulosic materials.” 1996. Web. 19 Jan 2020.
Vancouver:
Zahedifar M. Novel uses of lignin and hemicellulosic sugars from acid-hydrolysed lignocellulosic materials. [Internet] [Doctoral dissertation]. University of Aberdeen; 1996. [cited 2020 Jan 19].
Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=195786 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342205.
Council of Science Editors:
Zahedifar M. Novel uses of lignin and hemicellulosic sugars from acid-hydrolysed lignocellulosic materials. [Doctoral Dissertation]. University of Aberdeen; 1996. Available from: http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=195786 ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342205
Oregon State University
10.
Tantasucharit, Usicha.
Porosity, surface area and enzymatic saccharification of microcrystalline cellulose.
Degree: MS, Food Science and Technology, 1995, Oregon State University
URL: http://hdl.handle.net/1957/25991
► The research described in this thesis was aimed at understanding how particle size, porosity, and enzyme accessible surface area influence the rate of saccharification of…
(more)
▼ The research described in this thesis was aimed at understanding how particle
size, porosity, and enzyme accessible surface area influence the rate of saccharification
of microcrystalline cellulose. Microcrystalline cellulose (MCC) is a commonly used
substrate for the study of cellulolytic enzymes. MCC preparations of different particle
size are commercially available. In this study, MCC preparations having average particle
sizes of 20, 50, and 90 μm were analyzed with respect to their enzyme accessible surface
area, chemical and physical properties and rates of enzymatic saccharification.
Saccharification studies were done using a commercially available cellulase preparation
from Trichoderma reesei. Pore volume distributions were determined from solute
exclusion experiments. Internal surface areas were calculated based on the application of
the lamellae model to the pore volume distribution data. External surface areas were
calculated based on the average particle size of each MCC preparation assuming that the
particles could be represented as solid spheres. The different MCC preparations were
found to have nearly equivalent enzyme accessible surface areas per unit weight. Greater
than 99 % of the total enzyme accessible surface area for each MCC preparations was
found to be within the porous structure of the particles. Enzymatic saccharification
experiments demonstrated that the smaller particle size MCCs were more readily
digested than those of larger particle size. The similarity of the three MCC preparations
with respect to chemical and physical properties (other than particle size), pore volume
distribution, and total enzyme accessible surface area suggests that a rate limiting factor
in the enzymatic digestion of MCC is a resistance attributable to diffusion within the
capillary network of these insoluble substrates.
Advisors/Committee Members: Penner, Michael H. (advisor), Gamble, W. (committee member).
Subjects/Keywords: Lignocellulose – Biodegradation
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tantasucharit, U. (1995). Porosity, surface area and enzymatic saccharification of microcrystalline cellulose. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/25991
Chicago Manual of Style (16th Edition):
Tantasucharit, Usicha. “Porosity, surface area and enzymatic saccharification of microcrystalline cellulose.” 1995. Masters Thesis, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/25991.
MLA Handbook (7th Edition):
Tantasucharit, Usicha. “Porosity, surface area and enzymatic saccharification of microcrystalline cellulose.” 1995. Web. 19 Jan 2020.
Vancouver:
Tantasucharit U. Porosity, surface area and enzymatic saccharification of microcrystalline cellulose. [Internet] [Masters thesis]. Oregon State University; 1995. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/25991.
Council of Science Editors:
Tantasucharit U. Porosity, surface area and enzymatic saccharification of microcrystalline cellulose. [Masters Thesis]. Oregon State University; 1995. Available from: http://hdl.handle.net/1957/25991
Oregon State University
11.
Fenske, John J.
Quantitative polysaccharide analysis of lignocellulosic biomass.
Degree: MS, Food Science and Technology, 1994, Oregon State University
URL: http://hdl.handle.net/1957/27278
► Lignocellulosic biomass is a potential source of fermentable sugars such as glucose. Enzymatic hydrolysis of cellulose is a viable method of solubilizing the glucose from…
(more)
▼ Lignocellulosic biomass is a potential source of fermentable sugars such as
glucose. Enzymatic hydrolysis of cellulose is a viable method of solubilizing the
glucose from biomass, but the cellulose fraction of native lignocellulosic material
is shielded from enzymatic attack by the lignin-hemicellulose matrix
surrounding it. Pretreating lignocellulosic biomass with dilute sulfuric acid at
high temperatures solubilizes hemicellulose, rendering the cellulose fraction
more susceptible to enzymatic hydrolysis. Evaluation of dilute-acid, high-temperature
pretreatments depends on polysaccharide analysis of the two
fractions resulting from a pretreatment, prehydrolyzed solids(PHS) and
prehydrolyzate liquid(PH). The polysaccharide analysis is based on a method
described by the National Renewable Energy Laboratory and involves a two-stage
sulfuric acid hydrolysis followed by HPLC quantification using ion-moderated
partition chromatography and refractive index detection. The
subject
of this thesis is identifying and quantifying the sources of error associated with
the polysaccharide analysis and the error associated with the evaluation of the
effects of pretreatment on the polysaccharide fractions of switchgrass and poplar.
This was addressed by conducting replicate polysaccharide analyses on single
samples of native biomass, PHS, and PH. The variability associated with these
measurements was compared to the variability associated with replicate analyses
of identically pretreated biomass. It was found that the use of sugar standards to correct for sugar destroyed during the analysis adds error and most likely
overestimates the amount of sugar from biomass actually destroyed. It is evident
that assuming a volume after neutralization of the hydrolyzed biomass sample is
more reproducible than measuring the volume. When using a batch-type reactor
and the temperature and acid parameters used in this study,140°C-180°C/ 0.6-1.2
% sulfuric acid (w/w), it is evident that the major source of error in evaluating
pretreatment conditions is the pretreatment itself, not the analysis.
Advisors/Committee Members: Penner, Michael H. (advisor).
Subjects/Keywords: Lignocellulose – Biodegradation
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fenske, J. J. (1994). Quantitative polysaccharide analysis of lignocellulosic biomass. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/27278
Chicago Manual of Style (16th Edition):
Fenske, John J. “Quantitative polysaccharide analysis of lignocellulosic biomass.” 1994. Masters Thesis, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/27278.
MLA Handbook (7th Edition):
Fenske, John J. “Quantitative polysaccharide analysis of lignocellulosic biomass.” 1994. Web. 19 Jan 2020.
Vancouver:
Fenske JJ. Quantitative polysaccharide analysis of lignocellulosic biomass. [Internet] [Masters thesis]. Oregon State University; 1994. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/27278.
Council of Science Editors:
Fenske JJ. Quantitative polysaccharide analysis of lignocellulosic biomass. [Masters Thesis]. Oregon State University; 1994. Available from: http://hdl.handle.net/1957/27278
Oregon State University
12.
Chung, Yun-Chin.
Saccharification and fermentation of lignocellulosic biomass using Trichoderma reesei cellulases and Saccharomyces cerevisiae.
Degree: PhD, Food Science and Technology, 1996, Oregon State University
URL: http://hdl.handle.net/1957/27186
► The efficiency of cellulose hydrolysis under straight saccharification and simultaneous saccharification and fermentation (SSF) conditions was evaluated using three lignocellulosic materials (switchgrass, cornstover, and poplar),…
(more)
▼ The efficiency of cellulose hydrolysis under straight saccharification and
simultaneous saccharification and fermentation (SSF) conditions was evaluated using three
lignocellulosic materials (switchgrass, cornstover, and poplar), which had been pretreated
with dilute sulfuric acid under conditions which optimized xylose concentrations in the
prehydrolysate liquid. Yields of glucose, cellobiose and ethanol obtained from the
pretreated feedstocks were measured over 168 hrs. The final theoretical conversions of
cellulose from pretreated switchgrass, cornstover, and poplar in straight saccharification
were 85-100% (average 94%), 84-100% (average 96%), and 75-100% (average 87%),
respectively, while in SSF the conversions were 84-90% (average 87%), 91-96% (average
90%), 72%-82% (average 76%), respectively. The conversion rates of poplar in straight
saccharification and SSF were significantly lower than those of switchgrass and
cornstover. The effects of reaction parameters such as enzyme activity, cellulose
availability, and yeast cell viability on the extent of hydrolysis in straight saccharification and SSF were also studied. Results indicate that the lower glucose or ethanol yields
associated with some of the poplar were due to the recalcitrant nature of its cellulose.
To compare accurately the efficiencies between straight saccharification and SSF,
a direct method for determining the cellulose content of the feedstocks residues resulting
from SSF experiments has been developed and evaluated. The method improves on
classical cellulose assays by incorporating a yeast lysing enzyme to remove yeast glucans
from the feedstocks residue prior to acid hydrolysis and subsequent quantification of
cellulose derived glucose. A freeze-drying step was identified as necessary to render the
SSF yeast cells susceptible to enzyme lysis. The method was applied to the analysis of the
cellulose and yeast-glucan content of SSF residues from the three pretreated feedstocks.
Cellulose assays employing the lysing enzyme preparation demonstrated relative errors up
to 7.2% when yeast-associated glucan were not removed prior to analysis of SSF residues.
Enzymatic lysis of SSF yeast cells may be viewed as a general preparatory procedure to be
used prior to the subsequent chemical and physical analysis of SSF residues.
Advisors/Committee Members: Penner, Michael H. (advisor), Hashimoto, Andrew (committee member).
Subjects/Keywords: Lignocellulose – Biodegradation
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chung, Y. (1996). Saccharification and fermentation of lignocellulosic biomass using Trichoderma reesei cellulases and Saccharomyces cerevisiae. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/27186
Chicago Manual of Style (16th Edition):
Chung, Yun-Chin. “Saccharification and fermentation of lignocellulosic biomass using Trichoderma reesei cellulases and Saccharomyces cerevisiae.” 1996. Doctoral Dissertation, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/27186.
MLA Handbook (7th Edition):
Chung, Yun-Chin. “Saccharification and fermentation of lignocellulosic biomass using Trichoderma reesei cellulases and Saccharomyces cerevisiae.” 1996. Web. 19 Jan 2020.
Vancouver:
Chung Y. Saccharification and fermentation of lignocellulosic biomass using Trichoderma reesei cellulases and Saccharomyces cerevisiae. [Internet] [Doctoral dissertation]. Oregon State University; 1996. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/27186.
Council of Science Editors:
Chung Y. Saccharification and fermentation of lignocellulosic biomass using Trichoderma reesei cellulases and Saccharomyces cerevisiae. [Doctoral Dissertation]. Oregon State University; 1996. Available from: http://hdl.handle.net/1957/27186
RMIT University
13.
McKenzie, B.
Heterologous expression of cellulase enzymes in transplastidic Nicotiana tabacum cv. Petit Havana.
Degree: 2008, RMIT University
URL: http://researchbank.rmit.edu.au/view/rmit:6741
► Extensive research into enzyme-induced bio-conversion of lignocellulose to soluble sugars has been conducted and research continues in this area. Several approaches have been taken to…
(more)
▼ Extensive research into enzyme-induced bio-conversion of lignocellulose to soluble sugars has been conducted and research continues in this area. Several approaches have been taken to attempt to alleviate the economic problems associated with utilisation of lignocellulose in fuel ethanol production. By expressing cellulase genes in planta, it is hoped that the cost of enzyme-mediated hydrolysis of cellulose to its soluble sugar monomers, will be reduced. Some accomplishments have been made in this area using nuclear genetic transformation (Abdeev et al., 2003; Abdeev et al., 2004; Austin-Phillips et al., 1999; Biswas et al., 2006; Dai et al., 2000a,b; Dai et al., 2005; Jin et al., 2003; Kawazu et al., 1999; Sakka et al., 2000; Ziegelhoffer et al., 1999; Ziegelhoffer et al., 2001; Ziegler et al., 2000), but more research is required to bring the levels of cellulase enzyme expression in plants to levels that will make the process economically competitive. Chloroplasts of N. tabacum were selected as a target for transformation for high level expression due to their extremely high rates of transcription and translation. These were transformed with two genes, the e1 gene from A. cellulolyticus, and the cbh1 gene from T. reesei. Further aims included the investigation of the effects of using different promoters, and the novel use of both nuclear and chloroplast-based expression in a single plant, on the level of protein production in the heterologous host. Heterologous expression of the cbh1 gene was not successful. This is thought to be due to toxicity of the protein in a prokaryotic environment. Future studies should focus on trying to avoid this toxicity by targeting of the chloroplast-expressed enzyme to specific tissues, such as the thylakoid membrane, for containment, creating a codon-optimised synthetic gene that better mimics the codon usage of the plant to be used for expression, or placing the expression under a reactive cascade that is only activated upon exposure to an external trigger. Heterologous expression of the full length gene for E1 from A. cellulolyticus was successful. Chloroplast homology vectors under the constitutive promoter Prrn, and the inducible promoter T7, were constructed and these were used to successfully transform N. tabacum cv. Petit Havana chloroplasts. Stable transgenic plants were produced and evaluated by a variety of means, with the heterologously expressed enzyme showing activity against the soluble substrate analogue MUC of up to 3122 ± 466 pmol 4-MU/mg TSP/min and an E1 accumulation level of up to 0.35% ± 0.06 of the total soluble protein. Lastly, chloroplast transformation was combined with nuclear transformation to create novel dual-transgenic plants simultaneously expressing E1 from both the nuclear and chloroplast genomes. The combination of these technologies was very successful, with the heterologously expressed enzyme showing activity against the soluble substrate analogue MUC of up to 35706 ± 955 pmol 4-MU/mg TSP/min and an E1 accumulation level of up to 4.78%…
Subjects/Keywords: Fields of Research; Lignocellulose Biotechnology
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
McKenzie, B. (2008). Heterologous expression of cellulase enzymes in transplastidic Nicotiana tabacum cv. Petit Havana. (Thesis). RMIT University. Retrieved from http://researchbank.rmit.edu.au/view/rmit:6741
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
McKenzie, B. “Heterologous expression of cellulase enzymes in transplastidic Nicotiana tabacum cv. Petit Havana.” 2008. Thesis, RMIT University. Accessed January 19, 2020.
http://researchbank.rmit.edu.au/view/rmit:6741.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
McKenzie, B. “Heterologous expression of cellulase enzymes in transplastidic Nicotiana tabacum cv. Petit Havana.” 2008. Web. 19 Jan 2020.
Vancouver:
McKenzie B. Heterologous expression of cellulase enzymes in transplastidic Nicotiana tabacum cv. Petit Havana. [Internet] [Thesis]. RMIT University; 2008. [cited 2020 Jan 19].
Available from: http://researchbank.rmit.edu.au/view/rmit:6741.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
McKenzie B. Heterologous expression of cellulase enzymes in transplastidic Nicotiana tabacum cv. Petit Havana. [Thesis]. RMIT University; 2008. Available from: http://researchbank.rmit.edu.au/view/rmit:6741
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Nelson Mandela Metropolitan University
14.
Molaba, Tshepiso Princess.
Long term effects of temperature and humidity on lignocellulosic fibres and composites.
Degree: Faculty of Science, 2015, Nelson Mandela Metropolitan University
URL: http://hdl.handle.net/10948/10276
► The study deals with the chemical and flame retardant (FR) treatment of woven flax fabric and preparation and characterization of flax reinforced phenolic composites. Sheets…
(more)
▼ The study deals with the chemical and flame retardant (FR) treatment of woven flax fabric and preparation and characterization of flax reinforced phenolic composites. Sheets of flax fabric were subjected to chemical treatments using NaOH and silane coupling agents. A phosphate-based flame retardant (DAP) was applied to decrease the flammability of the flax fabric. The effect of the chemical treatments and FR treatments on the thermal and flammability properties of the fabric and composites was investigated using thermogravimetric analysis (TGA), vertical flame resistance test and cone calorimeter. The mechanical properties of the flax fabric and composites, before and after environmental ageing, were investigated. Ageing studies were carried out by exposing the samples in an environmental chamber at specified conditions for two weeks. TGA results showed that the treatment of the fabric with FR shifts the decomposition temperature to lower level and increases the char residue. Vertical flame resistance testing showed that FR treatment of the flax fabric improved the flammability properties. There was no after flame and afterglow observed for FR treated flax fabric due to self-extinguishment after removal of the flame. Flax Fabric without FR burned completely and there was no result for the char length due to the complete destruction of the fabric. The FR treatment, however, seemed to have had a negative effect on the tensile strength of the flax fabric. This was further intensified upon exposure of FR treated flax fabric to high temperatures during ageing studies which drastically reduced the tensile strength by more than 90%, and the flax fabric were found to be brittle and darker in visual appearance. TGA results of flax/phenolic composites showed that for composites containing chemically treated and FR treated flax fabric the decomposition temperatures shifted to lower temperatures; however there was no significant difference in the amount of char residue. Untreated flax/phenolic composites exhibited the lowest char residue. Cone calorimeter results showed that the peak heat release rate (PHRR), smoke production rate (SPR) and carbon dioxide (CO2) emission rate was reduced for the flax/phenolic composite produced using FR treated flax fabric. The tensile strength of these composites was reduced while there was an increase in modulus value. Exposure of the FR treated composites to high temperatures further reduced the tensile strength and increased the E-modulus. Both FR treated and untreated composites changed in colour and the FR treated composites were found to be brittle after exposure to high temperatures.
Subjects/Keywords: Lignocellulose; Fibrous composites; Textile fabrics
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Molaba, T. P. (2015). Long term effects of temperature and humidity on lignocellulosic fibres and composites. (Thesis). Nelson Mandela Metropolitan University. Retrieved from http://hdl.handle.net/10948/10276
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Molaba, Tshepiso Princess. “Long term effects of temperature and humidity on lignocellulosic fibres and composites.” 2015. Thesis, Nelson Mandela Metropolitan University. Accessed January 19, 2020.
http://hdl.handle.net/10948/10276.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Molaba, Tshepiso Princess. “Long term effects of temperature and humidity on lignocellulosic fibres and composites.” 2015. Web. 19 Jan 2020.
Vancouver:
Molaba TP. Long term effects of temperature and humidity on lignocellulosic fibres and composites. [Internet] [Thesis]. Nelson Mandela Metropolitan University; 2015. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/10948/10276.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Molaba TP. Long term effects of temperature and humidity on lignocellulosic fibres and composites. [Thesis]. Nelson Mandela Metropolitan University; 2015. Available from: http://hdl.handle.net/10948/10276
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Ryerson University
15.
Kang, Jin.
Improving bio-butanol production from lignocellulosic feedstock by tailoring metabolic perturbations.
Degree: 2017, Ryerson University
URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A7282
► The objective of this study is to enhance bio-butanol production using lignocellulosic feedstock via supplements of metabolism perturbation. Metabolic perturbations are non-substrate-based chemical additives that…
(more)
▼ The objective of this study is to enhance bio-butanol production using lignocellulosic feedstock via supplements of metabolism perturbation. Metabolic perturbations are non-substrate-based chemical additives that can reinforce metabolic flux towards butanol formation, or increase tolerance to microbial inhibitors in the feedstock. Typical metabolic perturbations include CaCO3, ZnSO4, methyl red, and furan derivatives such as furfural and hydroxymethylfurfural (HMF). In this study, we stepwise tailored metabolic perturbations to maximize butanol production from pure sugar and lignocellulosic feedstock. Under optimized conditions of 4 g/L CaCO3, 2 mg/L ZnSO4, butanol production exceeded 10g/L in wheat straw hydrolysate, which was significantly higher than that obtained in the absent of ZnSO4 and CaCO3. As compared to traditional lignocellulosic feedstock post-treatment method, metabolic perturbations method shows advantages in terms of productivity and economics. Improved bio-butanol production is related to the overexpression of NAD(P)H dependent genes.
Subjects/Keywords: Lignocellulose – Biotechnology; Butanol; Biomass energy
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kang, J. (2017). Improving bio-butanol production from lignocellulosic feedstock by tailoring metabolic perturbations. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A7282
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kang, Jin. “Improving bio-butanol production from lignocellulosic feedstock by tailoring metabolic perturbations.” 2017. Thesis, Ryerson University. Accessed January 19, 2020.
https://digital.library.ryerson.ca/islandora/object/RULA%3A7282.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kang, Jin. “Improving bio-butanol production from lignocellulosic feedstock by tailoring metabolic perturbations.” 2017. Web. 19 Jan 2020.
Vancouver:
Kang J. Improving bio-butanol production from lignocellulosic feedstock by tailoring metabolic perturbations. [Internet] [Thesis]. Ryerson University; 2017. [cited 2020 Jan 19].
Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A7282.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kang J. Improving bio-butanol production from lignocellulosic feedstock by tailoring metabolic perturbations. [Thesis]. Ryerson University; 2017. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A7282
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
16.
Schulz, Roland.
Development of High Performance Molecular Dynamics with Application to Multimillion-Atom Biomass Simulations.
Degree: 2015, University of Tennessee – Knoxville
URL: https://trace.tennessee.edu/utk_graddiss/3468
► An understanding of the recalcitrance of plant biomass is important for efficient economic production of biofuel. Lignins are hydrophobic, branched polymers and form a residual…
(more)
▼ An understanding of the recalcitrance of plant biomass is important for efficient economic production of biofuel. Lignins are hydrophobic, branched polymers and form a residual barrier to effective hydrolysis of lignocellulosic biomass. Understanding lignin's structure, dynamics and its interaction and binding to cellulose will help with finding more efficient ways to reduce its contribution to the recalcitrance. Molecular dynamics (MD) using the GROMACS software is employed to study these properties in atomic detail. Studying complex, realistic models of pretreated plant cell walls, requires simulations significantly larger than was possible before. The most challenging part of such large simulations is the computation of the electrostatic interaction. As a solution, the reaction-field (RF) method has been shown to give accurate results for lignocellulose systems, as well as good computational efficiency on leadership class supercomputers. The particle-mesh Ewald method has been improved by implementing 2D decomposition and thread level parallelization for molecules not accurately modeled by RF. Other scaling limiting computational components, such as the load balancing and memory requirements, were identified and addressed to allow such large scale simulations for the first time. This work was done with the help of modern software engineering principles, including code-review, continuous integration, and integrated development environments. These methods were adapted to the special requirements for scientific codes. Multiple simulations of lignocellulose were performed. The simulation presented primarily, explains the temperature-dependent structure and dynamics of individual softwood lignin polymers in aqueous solution. With decreasing temperature, the lignins are found to transition from mobile, extended to glassy, compact states. The low-temperature collapse is thermodynamically driven by the increase of the translational entropy and density fluctuations of water molecules removed from the hydration shell.
Subjects/Keywords: Lignocellulose; Molecular Dynamics; Supercomputer; Biophysics
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Schulz, R. (2015). Development of High Performance Molecular Dynamics with Application to Multimillion-Atom Biomass Simulations. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/3468
Chicago Manual of Style (16th Edition):
Schulz, Roland. “Development of High Performance Molecular Dynamics with Application to Multimillion-Atom Biomass Simulations.” 2015. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed January 19, 2020.
https://trace.tennessee.edu/utk_graddiss/3468.
MLA Handbook (7th Edition):
Schulz, Roland. “Development of High Performance Molecular Dynamics with Application to Multimillion-Atom Biomass Simulations.” 2015. Web. 19 Jan 2020.
Vancouver:
Schulz R. Development of High Performance Molecular Dynamics with Application to Multimillion-Atom Biomass Simulations. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2015. [cited 2020 Jan 19].
Available from: https://trace.tennessee.edu/utk_graddiss/3468.
Council of Science Editors:
Schulz R. Development of High Performance Molecular Dynamics with Application to Multimillion-Atom Biomass Simulations. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2015. Available from: https://trace.tennessee.edu/utk_graddiss/3468
University of Edinburgh
17.
Munns, Craig Christopher Robert.
Development of physio-chemical pretreatments and mixed microbial cultures for the conversion of lignocellulosic biomass to useful products.
Degree: PhD, 2017, University of Edinburgh
URL: http://hdl.handle.net/1842/28768
► There is increasing interest in producing biofuels; biofuels are preferable to fossil fuels as the biomass from which they are derived is seen as a…
(more)
▼ There is increasing interest in producing biofuels; biofuels are preferable to fossil fuels as the biomass from which they are derived is seen as a renewable source, as opposed to fossil fuels which are a finite resource. “First Generation” biofuels are derived from food crops such as grains and sugar cane. The use of food crops is not sustainable in this age of increasing food insecurity. A promising alternative appears to be what is termed “Second Generation” feedstocks, such as energy crops like Miscanthus spp., and agricultural by-products. The problem with the use of second generation feedstocks is firstly that the sugars are locked up in the cell wall polymers (CWP), which need to be released by physio-chemical pre-treatments, that are costly and time consuming. The second problem is that not all the sugars that are released from CWP are able to be utilised by wild type product-forming organisms. However, model chassis organisms can be genetically modified to utilise these sugars and /or produce enzymes to degrade biomass which reduces the time and costs involved in the process. While engineering these organisms to utilise a range of monosaccharides has already been successful, engineering them to produce degradation enzymes is proving to be problematic. A potentially more effective system is to use co-cultures of both cellulose-degrading and product-forming organisms. Since this is a novel approach it is not known whether the two organisms are able to live together without any adverse effects. The aims of this study were firstly to determine whether mixed cultures of both cellulose-degrading and potential product-forming organisms could survive in the presence of one another, secondly whether the cellulose-degrading organisms could degrade potential feedstock down into their monosaccharide building blocks and thirdly whether the potential product-forming organisms could survive and utilise these monosaccharides for growth and potential fermentation. It was discovered that C. hutchinsonii can degrade both paper and Triticum aestivum straw polymers into their monosaccharide components and that B. subtilis can survive on the sugars released by C. hutchinsonii. It was also discovered that C. hutchinsonii and B. subtilis 168 can only tolerate an ethanol concentration of up to 2% (v/v) and that this is below the baseline for a biofuel system to be economically viable. Likewise, C. hutchinsonii and B. subtilis 168 have an even poorer tolerance for butanol; growth is inhibited by < 1% butanol in its growth media. A series of physio-chemical pre-treatments were developed in order to make the monosaccharides present in the cell wall polymers more accessible to microbial saccharification. Sequential pre-treatments, both physical milling and chemical hydrolysis in tandem, had the greatest effect on the bio chemistry of the biomass, but that these physio-chemical pre-treatments produced inhibitory compounds in the medium that retarded microbial growth. Attempts were made to genetically modified Bacillus subtilis 168 to…
Subjects/Keywords: Lignocellulose; Bacillus subtilis 168
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Munns, C. C. R. (2017). Development of physio-chemical pretreatments and mixed microbial cultures for the conversion of lignocellulosic biomass to useful products. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/28768
Chicago Manual of Style (16th Edition):
Munns, Craig Christopher Robert. “Development of physio-chemical pretreatments and mixed microbial cultures for the conversion of lignocellulosic biomass to useful products.” 2017. Doctoral Dissertation, University of Edinburgh. Accessed January 19, 2020.
http://hdl.handle.net/1842/28768.
MLA Handbook (7th Edition):
Munns, Craig Christopher Robert. “Development of physio-chemical pretreatments and mixed microbial cultures for the conversion of lignocellulosic biomass to useful products.” 2017. Web. 19 Jan 2020.
Vancouver:
Munns CCR. Development of physio-chemical pretreatments and mixed microbial cultures for the conversion of lignocellulosic biomass to useful products. [Internet] [Doctoral dissertation]. University of Edinburgh; 2017. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1842/28768.
Council of Science Editors:
Munns CCR. Development of physio-chemical pretreatments and mixed microbial cultures for the conversion of lignocellulosic biomass to useful products. [Doctoral Dissertation]. University of Edinburgh; 2017. Available from: http://hdl.handle.net/1842/28768
Drexel University
18.
Berke-Schlessel, David.
Lignocellulosic biomass pretreatment using inorganic salts and simple organic acids, cellobiase encapsulation in mesoporous silica, and organosilica hybrid polymers.
Degree: 2010, Drexel University
URL: http://hdl.handle.net/1860/3413
► Alternative forms of green energy are becoming increasingly necessary as our supplies of fossil fuels begin to dwindle. As a result, research in green fuel…
(more)
▼ Alternative forms of green energy are becoming increasingly necessary as our supplies of fossil fuels begin to dwindle. As a result, research in green fuel technologies is becoming a necessity. One such green fuel is bio-ethanol that is used by degrading plant cellulose to generate fermentable sugars. A major drawback of this method is the fact that it is currently expensive and inefficient. The goal of this research was to find a viable path for making bio-ethanol a feasible alternative to petroleum based fuels.This research describes several processes for both increasing glucose yield of plant based cellulose hydrolysis, as well as reusing one of the more costly items in biomass hydrolysis, the enzyme. The first process for increasing glucose yield was through the pretreatment of raw plant matter. The plant matter was treated in refluxing solutions of 2.5% (w Iv) FeCb, or 2.5% oxalic acid with 0.5 M NaOH (the two methods that yielded the best results). Each of these methods effectively broke down the plant matter's protective lignin, exposing cellulose for enzymatic hydrolysis. Both methods significantly improved glucose yield, with the FeCb approach increasing yield by as much as 300%, and the oxalic acid method improving yields by as much as 450%.In order to reuse the cellulytic enzyme, cellobiase was encapsulated in mesoporous silica, using a fructose template to generate the pores. When using 50 or 70% fructose template, the cellobiase enzyme could be reused at least ten times (perhaps more) with out loosing enzymatic activity. This method of enzyme reuse could be an effective way to help cut costs, by minimizing the amount of expensive enzyme used.Additionally, this dissertation delves into a method for generating organosilane hybrid materials. These materials are important because they have the potential to retain the heat resistance of silane materials, while including the functionality of organic polymers. The materials made in this research include curcumin and syringaldazine as organic blocks, synthesized with silane reagents. The curcumin-silane hybrids demonstrated a moderate amount of biological activity when human myoblasts were grown on polymeric films. The syringaldazine-silane hybrids expressed the ability to be used as means of detecting chlorine gas.
Ph.D., Polymer Chemistry – Drexel University, 2010
Advisors/Committee Members: Wei, Yen, 1957-.
Subjects/Keywords: Molecular biology; Alzheimer's disease; Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Berke-Schlessel, D. (2010). Lignocellulosic biomass pretreatment using inorganic salts and simple organic acids, cellobiase encapsulation in mesoporous silica, and organosilica hybrid polymers. (Thesis). Drexel University. Retrieved from http://hdl.handle.net/1860/3413
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Berke-Schlessel, David. “Lignocellulosic biomass pretreatment using inorganic salts and simple organic acids, cellobiase encapsulation in mesoporous silica, and organosilica hybrid polymers.” 2010. Thesis, Drexel University. Accessed January 19, 2020.
http://hdl.handle.net/1860/3413.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Berke-Schlessel, David. “Lignocellulosic biomass pretreatment using inorganic salts and simple organic acids, cellobiase encapsulation in mesoporous silica, and organosilica hybrid polymers.” 2010. Web. 19 Jan 2020.
Vancouver:
Berke-Schlessel D. Lignocellulosic biomass pretreatment using inorganic salts and simple organic acids, cellobiase encapsulation in mesoporous silica, and organosilica hybrid polymers. [Internet] [Thesis]. Drexel University; 2010. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1860/3413.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Berke-Schlessel D. Lignocellulosic biomass pretreatment using inorganic salts and simple organic acids, cellobiase encapsulation in mesoporous silica, and organosilica hybrid polymers. [Thesis]. Drexel University; 2010. Available from: http://hdl.handle.net/1860/3413
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Waikato
19.
Williams, Thomas Carl.
The Microflora of the Huhu Grub
.
Degree: 2011, University of Waikato
URL: http://hdl.handle.net/10289/5336
► New Zealand's endemic longhorned beetle larvae, the Huhu grub (Prionoplus reticularis) feeds on dead coniferous wood. No studies have been conducted on its gut microflora.…
(more)
▼ New Zealand's endemic longhorned beetle larvae, the Huhu grub (Prionoplus reticularis) feeds on dead coniferous wood. No studies have been conducted on its gut microflora. Given that the Huhu grub feeds solely on lignocelluloses, it is likely that there are microorganisms present in its gut which are capable of degrading lignocelluloses to release energy rich sugars. This process of lignocelluloses release is the rate limiting step in the utilisation of woody material for bioprocesses such as bioethanol production. Microbial communities from wild grubs were compared with those raised on laboratory diets of either:
lignocellulose, cellulose, or complex nutrients. Bacterial gut communities were surveyed using 454 pyrosequencing of the variable 5 and 6 regions (400nt reads) of bacterial 16S rRNA genes as well as clone library analysis of the full length gene (1500bp). Fungal gut communities were analysed using cloning and Sanger sequencing of amplified fungal intergenic spacer (ITS) regions. The wild type gut bacterial population was highly diverse, with no known cellulose or lignin degraders detected in any abundance, although a strain of Burkholderia thought to be capable of nitrogen fixation was detected. No methanogenic archaea or acetogenic bacteria were detected. Fungal ITS sequences had high similarity with those of known lignin, hemicellulose and cellulose degraders in the public databases, and an uncultured Basidiomycete made up 51% of the wild type community, while species of the Penicillium genus dominated the grubs reared on laboratory diets of
lignocellulose. When grubs were reared on a diet of only cellulose the fungal community was dominated by a single species identified as Candida shehatae, a hemicellulose degrader known to associate with other longhorned beetle larvae. These fungi may be of interest for the biological conversion of lignocelluloses.
Advisors/Committee Members: Morgan, Hugh W (advisor).
Subjects/Keywords: Huhu;
Basidiomycete;
Burkholderia;
Penicillium;
Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Williams, T. C. (2011). The Microflora of the Huhu Grub
. (Masters Thesis). University of Waikato. Retrieved from http://hdl.handle.net/10289/5336
Chicago Manual of Style (16th Edition):
Williams, Thomas Carl. “The Microflora of the Huhu Grub
.” 2011. Masters Thesis, University of Waikato. Accessed January 19, 2020.
http://hdl.handle.net/10289/5336.
MLA Handbook (7th Edition):
Williams, Thomas Carl. “The Microflora of the Huhu Grub
.” 2011. Web. 19 Jan 2020.
Vancouver:
Williams TC. The Microflora of the Huhu Grub
. [Internet] [Masters thesis]. University of Waikato; 2011. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/10289/5336.
Council of Science Editors:
Williams TC. The Microflora of the Huhu Grub
. [Masters Thesis]. University of Waikato; 2011. Available from: http://hdl.handle.net/10289/5336
Michigan State University
20.
Bradshaw, Tamika Calicia.
Enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated reed canarygrass and switchgrass.
Degree: MS, Department of Chemical Engineering and Materials Science, 2005, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:33860
Subjects/Keywords: Hydrolysis; Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bradshaw, T. C. (2005). Enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated reed canarygrass and switchgrass. (Masters Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:33860
Chicago Manual of Style (16th Edition):
Bradshaw, Tamika Calicia. “Enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated reed canarygrass and switchgrass.” 2005. Masters Thesis, Michigan State University. Accessed January 19, 2020.
http://etd.lib.msu.edu/islandora/object/etd:33860.
MLA Handbook (7th Edition):
Bradshaw, Tamika Calicia. “Enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated reed canarygrass and switchgrass.” 2005. Web. 19 Jan 2020.
Vancouver:
Bradshaw TC. Enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated reed canarygrass and switchgrass. [Internet] [Masters thesis]. Michigan State University; 2005. [cited 2020 Jan 19].
Available from: http://etd.lib.msu.edu/islandora/object/etd:33860.
Council of Science Editors:
Bradshaw TC. Enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated reed canarygrass and switchgrass. [Masters Thesis]. Michigan State University; 2005. Available from: http://etd.lib.msu.edu/islandora/object/etd:33860
Baylor University
21.
Du, Bowen.
Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates.
Degree: Environmental Science., 2009, Baylor University
URL: http://hdl.handle.net/2104/5319
► A variety of inhibitory degradation products are produced during pretreatment of lignocellulosic biomass. Production and release of these degradation products is highly affected by the…
(more)
▼ A variety of inhibitory degradation products are produced during pretreatment of lignocellulosic biomass. Production and release of these degradation products is highly affected by the pH and redox potential of pretreatment reactions. Qualitative and quantitative interrogation of hydrolysates is paramount to identifying potential correlations between pretreatment chemistries and microbial inhibition in downstream bioconversion processes. In the present study, corn stover, poplar, and pine wood were pretreated under eight different chemical conditions, which are representative of leading pretreatment processes that have been investigated in recent years. Pretreatment processes included: 0.7% H2SO4, 0.07% H2SO4, liquid hot water, wet oxidation, neutral buffer solution, aqueous ammonia, lime, and oxidative lime. Forty lignocellulosic degradation products resulting from pretreatment were analyzed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and ion chromatography (IC) in order to determine correlations between concentrations of inhibitory degradation products and pretreatment chemistry.
Advisors/Committee Members: Chambliss, C. Kevin (advisor).
Subjects/Keywords: Lignocellulose – Biodegradation.;
Lignocellulose – Biotechnology.;
Biomass conversion.;
Agricultural wastes as fuel.
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Du, B. (2009). Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates.
(Thesis). Baylor University. Retrieved from http://hdl.handle.net/2104/5319
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Du, Bowen. “Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates.
” 2009. Thesis, Baylor University. Accessed January 19, 2020.
http://hdl.handle.net/2104/5319.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Du, Bowen. “Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates.
” 2009. Web. 19 Jan 2020.
Vancouver:
Du B. Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates.
[Internet] [Thesis]. Baylor University; 2009. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/2104/5319.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Du B. Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates.
[Thesis]. Baylor University; 2009. Available from: http://hdl.handle.net/2104/5319
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Hawaii – Manoa
22.
Lyford, Jeffrey Ross.
Bioprospecting for thermostable glycoside hydrolases : a metatranscriptomic approach.
Degree: 2016, University of Hawaii – Manoa
URL: http://hdl.handle.net/10125/100858
► M.S. University of Hawaii at Manoa 2012.
The conversion of cellulosic material from linear form to monomer is the rate-limiting step in current biofuels production…
(more)
▼ M.S. University of Hawaii at Manoa 2012.
The conversion of cellulosic material from linear form to monomer is the rate-limiting step in current biofuels production technologies from lignocellulosic material. The renewed focus on clean, sustainable, carbon-neutral fuels has resulted in increased interest in novel cellulolytic enzymes and microbial strains, with the aim to increase the efficiency of the above conversion. However, the availability of suitable cellulolytic enzymes has been restricted by the limited number of cellulolytic microbial strains in which these enzymes can be procured. One approach to increase efficiency has been to bioprospect novel thermophilic microbial strains, the logic being that an increase in production temperature will result in increased rates of lignocellulosic hydrolysis. Unfortunately, microbiologists have had limited success in cultivating cellulolytic thermophiles with only a small number of strains isolated.
The goal of this project was to circumvent the need to cultivate cellulolytic thermophiles by applying a metatranscriptomic approach to discover new thermostable cellulases commonly referred to as glycoside hydrolases (GH-enzymes that hydrolyze the glycosidic linkages between sugar molecules). This was achieved by employing a novel in situ enrichment technique to enrich for thermostable GHs directly from a geothermal environment. These GHs were being actively expressed by the resident microbial population to hydrolyse lignocellulose. This approach not only eliminated the need for cultivation, but also selected for the actively expressed GHs unregulated in response to the lignocellulosic material feedstock. This strategy removed the emphasis on identifying potentially relevant and substrate-active GHs from genomic data via genomic analysis of a cultivated microorganism or from environmental metagenomic surveys.
Subjects/Keywords: metatranscriptomics; glycoside hydrolase; bioprospecting; lignocellulose; bioethanol
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lyford, J. R. (2016). Bioprospecting for thermostable glycoside hydrolases : a metatranscriptomic approach. (Thesis). University of Hawaii – Manoa. Retrieved from http://hdl.handle.net/10125/100858
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lyford, Jeffrey Ross. “Bioprospecting for thermostable glycoside hydrolases : a metatranscriptomic approach.” 2016. Thesis, University of Hawaii – Manoa. Accessed January 19, 2020.
http://hdl.handle.net/10125/100858.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lyford, Jeffrey Ross. “Bioprospecting for thermostable glycoside hydrolases : a metatranscriptomic approach.” 2016. Web. 19 Jan 2020.
Vancouver:
Lyford JR. Bioprospecting for thermostable glycoside hydrolases : a metatranscriptomic approach. [Internet] [Thesis]. University of Hawaii – Manoa; 2016. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/10125/100858.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lyford JR. Bioprospecting for thermostable glycoside hydrolases : a metatranscriptomic approach. [Thesis]. University of Hawaii – Manoa; 2016. Available from: http://hdl.handle.net/10125/100858
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Penn State University
23.
Zuroff, Trevor Roman.
Engineering a microbial consortium for lignocellulosic
biofuel production.
Degree: PhD, Chemical Engineering, 2014, Penn State University
URL: https://etda.libraries.psu.edu/catalog/22540
► Lignocellulose represents an abundant, renewable resource for the production of liquid transportation fuels to fulfill the energy demand of a growing, developing global population. However,…
(more)
▼ Lignocellulose represents an abundant, renewable
resource for the production of liquid transportation fuels to
fulfill the energy demand of a growing, developing global
population. However, the recalcitrant nature of the biomaterial has
perplexed scientists for decades; lignocellulosic fuels still cost
two to five times more to produce than their petroleum-derived
counterparts. A novel class of bioprocess designs are necessary to
overcome the costs associated with conversion of this obstinate
feedstock. An intensified processing scheme, termed consolidated
bioprocessing, was touted as an economically feasible bioprocessing
strategy where consolidation of processing steps was thought to
enhance both process and economic efficiencies. Yet no single
organism has been discovered or engineered that is capable of
efficient consolidated bioprocessing. On the other hand, nature
executes what may be the ultimate consolidated bioprocess through
conversion of plant material to carbon dioxide and methane as part
of the global carbon cycle. The concerted action of numerous
naturally-occurring microorganisms overcomes many of the issues
encountered in industrial, single-organism lignocellulose
bioprocessing. In this dissertation, based on a nature-inspired
design, a two-member microbial consortium was developed for the
conversion of cellulose to fuel. Cooperation is induced between the
cellulolytic, anaerobic bacterium Clostridium phytofermentans and
Saccharomyces cerevisiae via oxygen diffusion, controlling
consortium populations and promoting fuel production. S. cerevisiae
consumes oxygen to protect C. phytofermentans which in return
degrades cellulose providing soluble carbon for the yeast. This
symbiotic design improves ethanol and/or hydrocarbon production
from purified cellulose over two-fold. Detailed analyses of C.
phytofermentans biofilm formation and fermentation characteristics
revealed that glucose and ethanol are robust inhibitors of C.
phytofermentans surface attachment and growth, respectively.
Ethanol tolerance was improved via strain evolution and metabolic
engineering was applied to overcome an adaptive reduction in
ethanol yield. Finally, a comprehensive mathematical framework was
developed to model the consortium and provide insight into the
intricate cooperation toward improving system productivity. In
summary, inspired by naturally occurring microbial ecosystems, this
dissertation describes the application of scientific and
engineering principles to improve the viability of microbial
consortia for industrial-scale conversion of lignocellulosic
biomass to fuel.
Subjects/Keywords: Lignocellulose; biofuels; Clostridium phytofermentans;
cellulose; microbial consortia
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zuroff, T. R. (2014). Engineering a microbial consortium for lignocellulosic
biofuel production. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/22540
Chicago Manual of Style (16th Edition):
Zuroff, Trevor Roman. “Engineering a microbial consortium for lignocellulosic
biofuel production.” 2014. Doctoral Dissertation, Penn State University. Accessed January 19, 2020.
https://etda.libraries.psu.edu/catalog/22540.
MLA Handbook (7th Edition):
Zuroff, Trevor Roman. “Engineering a microbial consortium for lignocellulosic
biofuel production.” 2014. Web. 19 Jan 2020.
Vancouver:
Zuroff TR. Engineering a microbial consortium for lignocellulosic
biofuel production. [Internet] [Doctoral dissertation]. Penn State University; 2014. [cited 2020 Jan 19].
Available from: https://etda.libraries.psu.edu/catalog/22540.
Council of Science Editors:
Zuroff TR. Engineering a microbial consortium for lignocellulosic
biofuel production. [Doctoral Dissertation]. Penn State University; 2014. Available from: https://etda.libraries.psu.edu/catalog/22540
Ryerson University
24.
Al Jibouri, Ali Kamel H.
Effect of Intermediate Washing on Ozonolysis Delignification and Enzymatic Hydrolysis of Wheat Straw.
Degree: 2012, Ryerson University
URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A1185
► Wheat straw was pretreated with ozone to increase the enzymatic hydrolysis yield. Ozonolysis pretreatment was performed in two stages with an intermediate washing step with…
(more)
▼ Wheat straw was pretreated with ozone to increase the enzymatic hydrolysis yield. Ozonolysis pretreatment was performed in two stages with an intermediate washing step with water in between. Part of the delignification products (lignin fragments) were removed by a washing step so ozone was used to oxidize more lignin rather than oxidizing lignin fragments.Three parameters, i.e. Initial Water Content (IWC) in wheat straw, Washing Starting Time (WST), and Washing Contact Time (WCT), were optimized to minimize Acid Insoluble Lignin (AIL) content of ozonated wheat straw. Performing an experiment using optimal parameters' values, i.e. IWC equal to 45 wt. %, WST equal to 20 minutes and WCT equal to 80 seconds, showed a drop in AIL content to 9.35 % with an increase in enzymatic hydrolysis yield to 80 % of the theoretical. Readjusting water content of wheat straw to 45 % before performing the 2nd ozonolysis stage further reduced AIL content to 7.36 % and increased the hydrolysis yield to 90 %. Increasing wheat straw fiber size from < 2 mm to < 6 mm decreased the hydrolysis yield to 72 %. All results were considered significant improvements when compared to untreated wheat straw with AIL content of 20.5 % and hydrolysis yield of 23 %.
Advisors/Committee Members: Turcotte, Ginette (Thesis advisor), Wu, Jiangning (Thesis advisor), Cheng, Chil-Hung (Thesis advisor), Ryerson University (Degree grantor), Ryerson University (Degree grantor).
Subjects/Keywords: Ozonolysis; Straw as fuel; Hydrolysis; Lignocellulose
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Al Jibouri, A. K. H. (2012). Effect of Intermediate Washing on Ozonolysis Delignification and Enzymatic Hydrolysis of Wheat Straw. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A1185
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Al Jibouri, Ali Kamel H. “Effect of Intermediate Washing on Ozonolysis Delignification and Enzymatic Hydrolysis of Wheat Straw.” 2012. Thesis, Ryerson University. Accessed January 19, 2020.
https://digital.library.ryerson.ca/islandora/object/RULA%3A1185.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Al Jibouri, Ali Kamel H. “Effect of Intermediate Washing on Ozonolysis Delignification and Enzymatic Hydrolysis of Wheat Straw.” 2012. Web. 19 Jan 2020.
Vancouver:
Al Jibouri AKH. Effect of Intermediate Washing on Ozonolysis Delignification and Enzymatic Hydrolysis of Wheat Straw. [Internet] [Thesis]. Ryerson University; 2012. [cited 2020 Jan 19].
Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A1185.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Al Jibouri AKH. Effect of Intermediate Washing on Ozonolysis Delignification and Enzymatic Hydrolysis of Wheat Straw. [Thesis]. Ryerson University; 2012. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A1185
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Ryerson University
25.
Dahahda, Samer.
Biological And Thermal Pretreatment Of Lignocellulosic Materials For Enhanced Biogas Production.
Degree: 2017, Ryerson University
URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A7118
► The rapid depletion of natural resources and the environmental concerns associated with the use of fossil fuels as the main source of global energy is…
(more)
▼ The rapid depletion of natural resources and the environmental concerns associated with the use of fossil fuels as the main source of global energy is leading to an increased interest in alternative and renewable energy sources. Lignocellulosic biomass is the most abundant source of organic materials that can be utilized as an energy source. Anaerobic digestion has been proven to be an effective technology for converting organic material into energy products such as biogas. However, the nature of lignocellulosic materials hinders the ability of microorganisms in an anaerobic digestion process to degrade and convert organic material to biogas. Therefore, a pretreatment step is necessary to improve the degradability of lignocellulosic materials and achieve higher biogas yield. Several pretreatment methods have been studied over the past few years including physical, thermal, chemical and biological pretreatment. This paper reviews biological and thermal pretreatment as two main promising methods used to improve biogas production from lignocelluloses. A greater focus is given on enzymatic pretreatment which is one of the promising yet under-researched biological pretreatment method. The paper addresses challenges in degrading lignocellulosic materials and the current status of research to improve biogas yield from lignocelluloses through biological and thermal pretreatment.
Subjects/Keywords: Biogas; Biodegradation; Renewable energy sources; Lignocellulose – Biodegradation
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Dahahda, S. (2017). Biological And Thermal Pretreatment Of Lignocellulosic Materials For Enhanced Biogas Production. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A7118
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Dahahda, Samer. “Biological And Thermal Pretreatment Of Lignocellulosic Materials For Enhanced Biogas Production.” 2017. Thesis, Ryerson University. Accessed January 19, 2020.
https://digital.library.ryerson.ca/islandora/object/RULA%3A7118.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Dahahda, Samer. “Biological And Thermal Pretreatment Of Lignocellulosic Materials For Enhanced Biogas Production.” 2017. Web. 19 Jan 2020.
Vancouver:
Dahahda S. Biological And Thermal Pretreatment Of Lignocellulosic Materials For Enhanced Biogas Production. [Internet] [Thesis]. Ryerson University; 2017. [cited 2020 Jan 19].
Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A7118.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Dahahda S. Biological And Thermal Pretreatment Of Lignocellulosic Materials For Enhanced Biogas Production. [Thesis]. Ryerson University; 2017. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A7118
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Ryerson University
26.
Dumitrache, Alexandru.
Description Of Associative Behaviour During Microbial Cellulose Utilization By Clostridium Thermocellum For Application In Advanced Biomass Conversion Process Development.
Degree: 2009, Ryerson University
URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A1706
► Recent findings support the concept that Clostridium thermocellum is a cellulose-utilizing specialist having growth benefits with increasing substrate chain length. We developed a continuous-flow system…
(more)
▼ Recent findings support the concept that Clostridium thermocellum is a cellulose-utilizing specialist having growth benefits with increasing substrate chain length. We developed a continuous-flow system for in-situ detection of cellulose colonization and qualitatively assayed metabolic activities and behaviour of cellulolytic cultures. This study demonstrates the existence of strongly adherent celluloytic cells arranged in monolayers with invariably end-on attached spores. The substrate-cell distance was recorded to be lower than 0.44 pm and a typical EPS matrix was absent. Measurements on carbon dioxide released in continuous-flow cultures was successfully employed to monitor biofilm activity and total carbohydrate assays do not reveal loss of cellulolysis end-products in the effluent. These findings demonstrate the bacteria have optimized access to the cellulosic substrates and suggest that they have an ability to sequester products of substrate hydrolysis which confers benefits over non-adherent cellulolytic or non-cellulolytic organisms.
Advisors/Committee Members: Wolfaardt, Gideon M. (Thesis advisor), Lynd, Lee R. (Thesis advisor), Ryerson University (Degree grantor).
Subjects/Keywords: Biomass energy; Biomass conversion; Lignocellulose – Biotechnology
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Dumitrache, A. (2009). Description Of Associative Behaviour During Microbial Cellulose Utilization By Clostridium Thermocellum For Application In Advanced Biomass Conversion Process Development. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A1706
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Dumitrache, Alexandru. “Description Of Associative Behaviour During Microbial Cellulose Utilization By Clostridium Thermocellum For Application In Advanced Biomass Conversion Process Development.” 2009. Thesis, Ryerson University. Accessed January 19, 2020.
https://digital.library.ryerson.ca/islandora/object/RULA%3A1706.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Dumitrache, Alexandru. “Description Of Associative Behaviour During Microbial Cellulose Utilization By Clostridium Thermocellum For Application In Advanced Biomass Conversion Process Development.” 2009. Web. 19 Jan 2020.
Vancouver:
Dumitrache A. Description Of Associative Behaviour During Microbial Cellulose Utilization By Clostridium Thermocellum For Application In Advanced Biomass Conversion Process Development. [Internet] [Thesis]. Ryerson University; 2009. [cited 2020 Jan 19].
Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A1706.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Dumitrache A. Description Of Associative Behaviour During Microbial Cellulose Utilization By Clostridium Thermocellum For Application In Advanced Biomass Conversion Process Development. [Thesis]. Ryerson University; 2009. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A1706
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Massey University
27.
Palevich, Nikola.
Genome sequencing of rumen bacteria involved in lignocellulose digestion.
Degree: MS, the Institute of Molecular Biosciences, 2011, Massey University
URL: http://hdl.handle.net/10179/2911
► Determining the role of rumen microbes and their enzymes in plant polysaccharide breakdown is fundamental to understanding digestion and maximising productivity in ruminant animals. In…
(more)
▼ Determining the role of rumen microbes and their enzymes in plant polysaccharide breakdown is fundamental to understanding digestion and maximising productivity in ruminant animals. In order to learn more about lignocellulose degradation in pasture-grazed dairy cows under NZ conditions, twenty representative strains from five major phylotype clusters (Butyrivibrio fibrisolvens/hungatei cluster 383, Pseudobutyrivibrio xylanivorans clusters 247 and 245, Selenomonas ruminantium cluster 212, and Lachnospiraceae cluster 121), cultivated directly from the fibre-adherent rumen microbial fraction of dairy cows were selected. Genotypic and phenotypic analysis of these strains led to identification of Butyrivibrio sp. MB2003 that adheres to and efficiently degrades the plant fibre. The 3.3 Mb MB2003 genome was sequenced and annotated and found to consist of four replicons: a chromosome (7 contigs, in 1 super scaffold), a chromid (Bhu II), a megaplasmid (pNP144) and a small plasmid (pNP6). A novel feature of the MB2003 genome is the presence of a chromid (Bhu II) which is now the smallest chromid reported for all bacteria. The MB2003 polysaccharide-degrading enzymes, surface structures and predicted strategy for attachment to, and degradation of, complex polysaccharides was found to be comparable to that of the fibrolytic bacterium Butyrivibrio proteoclasticus B316. Both MB2003 and B316 are non-motile, despite the presence of flagellar gene clusters, and utilise a range of insoluble plant polysaccharides, but not cellulose. Xylan is the preferred insoluble substrate of MB2003 and its genome encodes a large repertoire of enzymes predicted to metabolise this complex polysaccharide. The MB2003 draft genome produced in this work is the first opportunity to conduct comparative analysis of two rumen bacteria belonging to the same genus. Although both MB2003 and B316 have similar phenotypic characteristics and occupy the same habitat, the genome of MB2003 is much smaller and contains fewer extracellular polysaccharide degrading enzymes. From this comparison it can be concluded that MB2003 is a secondary hemicellulose degrader, offering an alternate view of the genes required for a xylanolytic lifestyle in the rumen, and posing an interesting question about the purpose of the wider range of polysaccharide degrading enzymes found in B316.
Subjects/Keywords: Rumen microbiology;
Lignocellulose degradation;
Bacterial genetics;
Butyrivibrio
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Palevich, N. (2011). Genome sequencing of rumen bacteria involved in lignocellulose digestion. (Masters Thesis). Massey University. Retrieved from http://hdl.handle.net/10179/2911
Chicago Manual of Style (16th Edition):
Palevich, Nikola. “Genome sequencing of rumen bacteria involved in lignocellulose digestion.” 2011. Masters Thesis, Massey University. Accessed January 19, 2020.
http://hdl.handle.net/10179/2911.
MLA Handbook (7th Edition):
Palevich, Nikola. “Genome sequencing of rumen bacteria involved in lignocellulose digestion.” 2011. Web. 19 Jan 2020.
Vancouver:
Palevich N. Genome sequencing of rumen bacteria involved in lignocellulose digestion. [Internet] [Masters thesis]. Massey University; 2011. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/10179/2911.
Council of Science Editors:
Palevich N. Genome sequencing of rumen bacteria involved in lignocellulose digestion. [Masters Thesis]. Massey University; 2011. Available from: http://hdl.handle.net/10179/2911
Université de Sherbrooke
28.
Labranche, Joey.
Concentration et transformation de la biomasse algale dans un procédé synergique de production de biocarburant
.
Degree: 2019, Université de Sherbrooke
URL: http://hdl.handle.net/11143/14947
► Ce projet présente une méthode, ainsi que des résultats, visant à contrer deux verrous technologiques limitant actuellement la production à échelle industrielle de biomasse microalgale…
(more)
▼ Ce projet présente une méthode, ainsi que des résultats, visant à contrer deux verrous
technologiques limitant actuellement la production à échelle industrielle de biomasse
microalgale soit : 1) la concentration (dewatering) de cette biomasse et 2) l’extraction de
métabolites d’intérêt (carbohydrates, lipides, protéines) à partir de ce substrat. Dans ce projet,
de la
lignocellulose et de la cellulose sont utilisées pour la concentration de la solution
microalgale, agissant comme média filtrant. L’avantage conceptuel de la méthode proposée
est qu'elle s'intègre à des procédés établis. Dans un premier temps, une étape de préconcentration
sera utilisée afin de diminuer le volume de la solution d'algues envoyée à la
filtration (qui est l`étape majeure de la concentration) tout en permettant la récupération d'une
portion du milieu de culture. Cette étape s'effectuera via une variation de la concentration
ionique du milieu pour induire la floculation et la sédimentation des algues. Dans un second
temps, pour permettre la filtration des algues, une préparation préalable de la fibre
(lignocellulosique et cellulosique) selon des traitements à la vapeur de différentes sévérités
permettra de voir l’influence de ces traitements sur les paramètres physiques des fibres. Cette
opération permettra d’une part d’évaluer l’influence de ce prétraitement sur l'efficacité de
filtration, et d’autre part, de l'adapter aux conditions opérationnelles en industrie. L’objectif
est de bien saisir la capacité de filtration des différents médias afin d’optimiser la filtration des
microalgues sans avoir à modifier significativement les paramètres d’opération actuels du
système de vapocraquage. Une fois les algues captées par les fibres, le mélange d’algues et de
fibres est ensuite traité de 2 façons différentes dépendamment du type de filtration effectuée.
La méthode proposée va différer selon la composition initiale des microalgues. Si la
concentration en lipides est plus élevée que la concentration en sucres, la filtration sur la
lignocellulose va être utilisée pour ensuite transformer, par vapocraquage, l’ensemble
microalgues-
lignocellulose en intermédiaires valorisables dérivés des lipides et des sucres. Si,
à l'inverse, la concentration en sucre est plus élevée, la cellulose servira de média filtrant pour
ensuite être hydrolysée par un traitement non enzymatique. Le procédé, qui éventuellement
découlera de la méthode proposée, pourra alors être adapté aux différentes souches de
microalgues dans l'objectif final de production de différents types de biocarburants et/ou
biocommodités. La méthode développée exige que les cultures de microalgues soient faites à
proximité de bioraffineries existantes, car les quantités de cellulose et, surtout, de
lignocellulose nécéssaire sont supérieures aux quantités d’algues retenues. La méthode fait du
sens si des eaux usées produites dans la bioraffinerie ou à proximité peuvent être traitées par
les microalgues (totalement ou en partie en combinaison avec des boues activées).…
Advisors/Committee Members: Lavoie, Jean-Michel (advisor).
Subjects/Keywords: Microalgues;
Biocarburant;
Lignocellulose;
Cellulose;
Fermentation;
Vapocraquage
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Labranche, J. (2019). Concentration et transformation de la biomasse algale dans un procédé synergique de production de biocarburant
. (Masters Thesis). Université de Sherbrooke. Retrieved from http://hdl.handle.net/11143/14947
Chicago Manual of Style (16th Edition):
Labranche, Joey. “Concentration et transformation de la biomasse algale dans un procédé synergique de production de biocarburant
.” 2019. Masters Thesis, Université de Sherbrooke. Accessed January 19, 2020.
http://hdl.handle.net/11143/14947.
MLA Handbook (7th Edition):
Labranche, Joey. “Concentration et transformation de la biomasse algale dans un procédé synergique de production de biocarburant
.” 2019. Web. 19 Jan 2020.
Vancouver:
Labranche J. Concentration et transformation de la biomasse algale dans un procédé synergique de production de biocarburant
. [Internet] [Masters thesis]. Université de Sherbrooke; 2019. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/11143/14947.
Council of Science Editors:
Labranche J. Concentration et transformation de la biomasse algale dans un procédé synergique de production de biocarburant
. [Masters Thesis]. Université de Sherbrooke; 2019. Available from: http://hdl.handle.net/11143/14947
Oregon State University
29.
Zauscher, Stefan.
Orienting lignocellulosic fibers by means of a magnetic field.
Degree: MS, Materials Science, 1992, Oregon State University
URL: http://hdl.handle.net/1957/36066
► Controlling the orientation and spatial distribution of discontinuous fibers in composite materials enables product properties to be tailored to anticipated use. Electric fields are already…
(more)
▼ Controlling the orientation and spatial distribution of
discontinuous fibers in composite materials enables product
properties to be tailored to anticipated use. Electric
fields are already (albeit rarely) used to affect alignment
in lignocellulosic (LC) fiber composites. The use of
magnetic fields has not, however, been suggested or
explored; this is apparently because LC fibers are
essentially non-magnetic. The approach may offer, however,
some considerable advantages, as long as ferromagnetism may
be imparted to the fibers.
In the present research several fiber modification
processes were considered and two, electroless nickel
plating and spray application of a coating containing nickel
in suspension, were investigated in more depth. The latter
was chosen to render highly engineered, elongated wood
particles responsive to magnetic fields. Individual treated
particles were suspended in viscous, newtonian silicone
fluids and their rotation under the influence of a
controlled magnetic field was video recorded.
The magnetic torque on the particle was, under the
above conditions, directly proportional to the fluid
viscosity, to the particle's angular velocity and to a
characteristic shape constant. The maximum of the specific
magnetic torque (magnetic torque divided by the shape
constant) was found to reflect the influence of field
strength and particle Ni-treatment on rotation. Results
were scaled to an arbitrarily chosen viscosity for
comparison.
The dependencies of the magnetic torque found in the
present research compare with those theoretically predicted
for ellipsoidal and cylindrical bodies. For field strengths
ranging from 0.07T to 0.15T (below magnetic saturation) the
magnetic torque increased almost linearly with increasing
field strength. Magnetic torque was also found to increase
nearly linearly with increasing bulk Ni-concentration (5g/kg
- 50g/kg).
Rotational motion was sometimes impeded at low field
strengths and this was attributed to a permanent magnetic
moment obtained by the particle. A coercive field strength
of 7600A/m supported this hypothesis. Judiciously switched
field polarity increased magnetic torque at small alignment
angles.
The present research indicates that orienting LC fibers
with magnetic fields is possible and promising. To study
dynamics of fiber motion in low viscosity fluids, such as
air, a different experimental method is necessary; however,
dependencies of the magnetic torque found in the present
study still hold true.
Advisors/Committee Members: Humphrey, Philip E. (advisor).
Subjects/Keywords: Lignocellulose – Magnetic properties
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zauscher, S. (1992). Orienting lignocellulosic fibers by means of a magnetic field. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/36066
Chicago Manual of Style (16th Edition):
Zauscher, Stefan. “Orienting lignocellulosic fibers by means of a magnetic field.” 1992. Masters Thesis, Oregon State University. Accessed January 19, 2020.
http://hdl.handle.net/1957/36066.
MLA Handbook (7th Edition):
Zauscher, Stefan. “Orienting lignocellulosic fibers by means of a magnetic field.” 1992. Web. 19 Jan 2020.
Vancouver:
Zauscher S. Orienting lignocellulosic fibers by means of a magnetic field. [Internet] [Masters thesis]. Oregon State University; 1992. [cited 2020 Jan 19].
Available from: http://hdl.handle.net/1957/36066.
Council of Science Editors:
Zauscher S. Orienting lignocellulosic fibers by means of a magnetic field. [Masters Thesis]. Oregon State University; 1992. Available from: http://hdl.handle.net/1957/36066
Mississippi State University
30.
Mondala, Andro Hernandez.
ENHANCED LIPID PRODUCTION AND BIODIESEL YIELDS FROM ACTIVATED SLUDGE VIA FERMENTATION OF LIGNOCELLULOSE HYDROLYZATE.
Degree: PhD, Chemical Engineering, School of, 2010, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-11062010-021634/
;
► The potential of enhancing lipid accumulation in municipal sewage activated sludge via fermentation of lignocellulose biomass hydrolyzate was investigated. The overall objective was to…
(more)
▼ The potential of enhancing lipid accumulation in municipal sewage activated
sludge via fermentation of
lignocellulose biomass hydrolyzate was investigated. The
overall objective was to increase the levels of feedstock lipids in the activated sludge
biomass and increase its biodiesel yield via <i>in situ</i> or <i>ex situ</i> transesterification; and
improve its cost competitiveness as an abundant feedstock source for biofuels production.
To reduce production costs and maintain environmental sustainability, influent
wastewater and waste
lignocellulose biomass hydrolyzate were used as cultivation media
and substrate, respectively. However,
lignocellulose hydrolyzates also contain
degradation by-products such as furfural and acetic acid that are known to exert
inhibitory effects on microorganisms; hence their effects on the fermentative performance
of activated sludge were investigated and fermentation strategies were proposed and
evaluated to counteract the microbial toxicity of these compounds. The utilization rate
and efficiency of xylose by activated sludge microorganisms for lipid production was
also evaluated as pentose sugars such as xylose usually constitute a major percentage of
lignocellulose hydrolyzates. Furthermore, variations in the population profile of activated
sludge microbiota were determined via 16S rRNA sequence analysis to determine the
effect of sugar fermentation at different initial conditions. Results show that activated
sludge lipid contents and biodiesel yield could be enhanced by fermentation of sugars at a
high initial C:N ratio (70:1). Furfural was found to be highly inhibitory to microbial
growth and lipid accumulation while high initial acetic acid concentrations enhanced
biomass production but not lipid formation. Xylose was also utilized more efficiently
than glucose by the activated sludge microorganisms for biomass and lipid production
albeit at relatively slower rates; hence sugar mixtures derived from
lignocellulose could
be utilized for the process. Semicontinuous and continuous fermentation modes were
proposed and evaluated as strategies to reduce inhibitory effect of furfural and acetic acid
and improve lipid productivity, but the lack of nutrient supplementation prevented the
cultures from sustaining microbial growth and lipid production, leading to cell death and
washout. Finally, the reduction in the diversity of the activated sludge microbiota could
point to specific microbial strains that are mainly responsible for lipid accumulation.
Advisors/Committee Members: Keisha Walters (committee member), W. Todd French (committee member), R. Mark Bricka (committee member), Bill Elmore (committee member), Benjamin Magbanua (committee member), Rafael Hernandez (chair).
Subjects/Keywords: lignocellulose; fermentation; biodiesel; lipids; municipal sewage sludge
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share
❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mondala, A. H. (2010). ENHANCED LIPID PRODUCTION AND BIODIESEL YIELDS FROM ACTIVATED SLUDGE VIA FERMENTATION OF LIGNOCELLULOSE HYDROLYZATE. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-11062010-021634/ ;
Chicago Manual of Style (16th Edition):
Mondala, Andro Hernandez. “ENHANCED LIPID PRODUCTION AND BIODIESEL YIELDS FROM ACTIVATED SLUDGE VIA FERMENTATION OF LIGNOCELLULOSE HYDROLYZATE.” 2010. Doctoral Dissertation, Mississippi State University. Accessed January 19, 2020.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-11062010-021634/ ;.
MLA Handbook (7th Edition):
Mondala, Andro Hernandez. “ENHANCED LIPID PRODUCTION AND BIODIESEL YIELDS FROM ACTIVATED SLUDGE VIA FERMENTATION OF LIGNOCELLULOSE HYDROLYZATE.” 2010. Web. 19 Jan 2020.
Vancouver:
Mondala AH. ENHANCED LIPID PRODUCTION AND BIODIESEL YIELDS FROM ACTIVATED SLUDGE VIA FERMENTATION OF LIGNOCELLULOSE HYDROLYZATE. [Internet] [Doctoral dissertation]. Mississippi State University; 2010. [cited 2020 Jan 19].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-11062010-021634/ ;.
Council of Science Editors:
Mondala AH. ENHANCED LIPID PRODUCTION AND BIODIESEL YIELDS FROM ACTIVATED SLUDGE VIA FERMENTATION OF LIGNOCELLULOSE HYDROLYZATE. [Doctoral Dissertation]. Mississippi State University; 2010. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-11062010-021634/ ;
◁ [1] [2] [3] [4] [5] [6] [7] [8] [9] ▶
. 
Open Access Theses and Dissertations
