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McMaster University
1.
Kazemi, Amir Sadegh.
Development of stirred well filtration as a high-throughput technique for downstream bioprocessing.
Degree: MASc, 2014, McMaster University
URL: http://hdl.handle.net/11375/16153
► Micro-scale processing (MSP) techniques are miniaturized version of upstream and downstream conventional unit operations that are designed to accelerate the pace of bioprocess design and…
(more)
▼ Micro-scale processing (MSP) techniques are miniaturized version of upstream and downstream conventional unit operations that are designed to accelerate the pace of bioprocess design and development. Previous ‘dead end’ filtration studies have demonstrated the usefulness of this concept for membrane filtration processes. However, these experiments were performed without stirring which is the most common strategy to control the effects of concentration polarization and fouling on filtration performance.
In this work, the pressure-driven stirred conditions of a conventional stirred-cell module were integrated with a 96-well filter plate to develop a high throughput technique called ‘stirred-well filtration’ (SWF). The design allowed for up to eight constant flux filtration experiments to be conducted at once using a multi-rack programmable syringe pump and a magnetic lateral tumble stirrer. An array of pressure transducers was used to monitor the transmembrane pressure (TMP) in each well. The protein sieving behavior and fouling propensity of Omega™ ultrafiltration membranes were assessed via a combination of hydraulic permeability measurements and protein sieving tests in constant filtrate flux mode. The TMP profile during filtration of bovine serum albumin (BSA) solution was strongly dependent on the stirring conditions – for example the maximum TMP in the stirred wells were an average of 7.5, 3.8, and 2.6 times lower than those in the unstirred wells at filtrate fluxes of 12, 36, and 60 LMH (5, 15, and 25 μL/min) respectively. The consistency of the data across different wells for the same stirring condition was very good. To demonstrate the effectiveness of the SWF technique, the eight tests for a simple 22 factorial design-of-experiments (DOE) test with duplicates was run to evaluate the effect of solution pH and salt concentration on protein filtration. The combination of SWF with statistical methods such as DOE is shown to be an effective strategy for high-throughput optimization of membrane filtration processes.
Dissertation
Master of Applied Science (MASc)
Advisors/Committee Members: Latulippe, David, Chemical Engineering.
Subjects/Keywords: Microscale processing; High-throughput testing; Downstream bioprocessing; Stirred well filtration (SWF); BSA filtration; Micromixing; Fouling test; Omega™ membrane
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Chicago ·
MLA ·
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APA (6th Edition):
Kazemi, A. S. (2014). Development of stirred well filtration as a high-throughput technique for downstream bioprocessing. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/16153
Chicago Manual of Style (16th Edition):
Kazemi, Amir Sadegh. “Development of stirred well filtration as a high-throughput technique for downstream bioprocessing.” 2014. Masters Thesis, McMaster University. Accessed February 27, 2021.
http://hdl.handle.net/11375/16153.
MLA Handbook (7th Edition):
Kazemi, Amir Sadegh. “Development of stirred well filtration as a high-throughput technique for downstream bioprocessing.” 2014. Web. 27 Feb 2021.
Vancouver:
Kazemi AS. Development of stirred well filtration as a high-throughput technique for downstream bioprocessing. [Internet] [Masters thesis]. McMaster University; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/11375/16153.
Council of Science Editors:
Kazemi AS. Development of stirred well filtration as a high-throughput technique for downstream bioprocessing. [Masters Thesis]. McMaster University; 2014. Available from: http://hdl.handle.net/11375/16153

East Tennessee State University
2.
Litwin, Nicole S.
Assessment of Red Blood Cell Membrane Fatty Acid Composition in Relation to Dietary Intake in Patients Undergoing Cardiac Catheterization.
Degree: MS, Clinical Nutrition, 2014, East Tennessee State University
URL: https://dc.etsu.edu/etd/2319
► Red blood cells (RBC) have been shown to mediate plaque development seen in coronary artery disease (CAD). This study determined whether differences in RBC…
(more)
▼ Red blood cells (RBC) have been shown to mediate plaque development seen in coronary artery disease (CAD). This study determined whether differences in RBC fatty acid (FA) composition were related to CAD risk. FAs were extracted from RBCs of 38 individuals who have undergone cardiac catheterization, 9 of whom had obstructive CAD, and analyzed via gas chromatography. Ferric reducing ability of plasma (FRAP) assay was used to determine oxidative stress. Food frequency questionnaires were used to correlate RBC omega-3 FA to daily intake of omega-3 FA. No correlation was found between RBC content and intake of omega-3 FA. FRAP values and RBC FA composition did not differ between the 2 groups with exception of the saturated FA, palmitic acid (p=0.018). These results suggest that RBC FA composition may differ between individuals with or at risk for CAD. Additional research is needed to validate this biomarker as a predictor of CAD.
Subjects/Keywords: red blood cell membrane; fatty acid composition; omega-3 fatty acids; coronary artery disease; oxidative stress; Dietetics and Clinical Nutrition
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❌
APA ·
Chicago ·
MLA ·
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CSE |
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APA (6th Edition):
Litwin, N. S. (2014). Assessment of Red Blood Cell Membrane Fatty Acid Composition in Relation to Dietary Intake in Patients Undergoing Cardiac Catheterization. (Thesis). East Tennessee State University. Retrieved from https://dc.etsu.edu/etd/2319
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):
Litwin, Nicole S. “Assessment of Red Blood Cell Membrane Fatty Acid Composition in Relation to Dietary Intake in Patients Undergoing Cardiac Catheterization.” 2014. Thesis, East Tennessee State University. Accessed February 27, 2021.
https://dc.etsu.edu/etd/2319.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Litwin, Nicole S. “Assessment of Red Blood Cell Membrane Fatty Acid Composition in Relation to Dietary Intake in Patients Undergoing Cardiac Catheterization.” 2014. Web. 27 Feb 2021.
Vancouver:
Litwin NS. Assessment of Red Blood Cell Membrane Fatty Acid Composition in Relation to Dietary Intake in Patients Undergoing Cardiac Catheterization. [Internet] [Thesis]. East Tennessee State University; 2014. [cited 2021 Feb 27].
Available from: https://dc.etsu.edu/etd/2319.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Litwin NS. Assessment of Red Blood Cell Membrane Fatty Acid Composition in Relation to Dietary Intake in Patients Undergoing Cardiac Catheterization. [Thesis]. East Tennessee State University; 2014. Available from: https://dc.etsu.edu/etd/2319
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université de Grenoble
3.
Ftouni, Hossein.
Transport thermique dans des membranes très minces de SiN amorphe : Thermal transport in very thin amorphous SiN membranes.
Degree: Docteur es, Physique, 2013, Université de Grenoble
URL: http://www.theses.fr/2013GRENY046
► Afin de comprendre les mécanismes de transport de la chaleur dans des films très minces des matériaux amorphes, nous avons proposé et démontré expérimentalement une…
(more)
▼ Afin de comprendre les mécanismes de transport de la chaleur dans des films très minces des matériaux amorphes, nous avons proposé et démontré expérimentalement une nouvelle technique de mesure des propriétés thermiques de membranes très minces. Cette technique consiste à coupler la méthode 3 oméga avec la géométrie Völklein (membrane suspendue allongée). L'échantillon d'intérêt est alors monté dans un pont de Wheatstone spécifique afin d'éliminer le signal électrique 1 oméga. Cette technique permet de mesurer avec une très haute sensibilité le signal thermique 3 oméga et donc les propriétés thermiques des membranes. Le nitrure de silicium étudié dans ce travail constitue un matériau amorphe typique. Nous avons été intéressés par l'étude du transport thermique dans un tel système de dimensions réduites en fonction de la température et du stress intrinsèque qui présente dans les films. Afin d'atteindre cet objectif, les membranes de nitrure de silicium de stress élevé et de faible niveau de stress ont été mesurées respectivement pour une épaisseur de 50 nm et 100 nm. Le comportement global de la conductivité thermique mesurée est une croissance quand la température augmente, une tendance généralement constaté pour un matériau amorphe. Le data de membrane de 50 nm présente une conductivité thermique inférieure à celle du 100 nm, ce qui est en accord avec l'effet des dimensions réduites. La chaleur spécifique mesurée s'écarte sensiblement de la loi en T3 de Debye. Cela est particulièrement important en dessous de 100 K où la chaleur spécifique est plus élevé que celle prévue par la modèle Debye. Ces résultats expérimentaux sont en excellent accord avec les prévisions d'un model théorique qui tient en compte de l'effet TLS (Two Level System) qui présente dans le matériaux amorphe. Il a été montré expérimentalement que le stress n'a pas d'effet sur la chaleur spécifique de nitrure de silicium. De plus, nous avons démontré que le stress n'affecte pas la dissipation dans nitrure de silicium, et la dissipation par dilution semble être la cause de la réduction de la dissipation. Par conséquent, le stress ne devrait pas affecter la conductivité thermique du nitrure de silicium, ce qui est cohérent avec les résultats expérimentaux. En terme d'application de la méthode 3 oméga-Völklein, nous avons démontré que la membrane de SiN peut être utilisée comme capteur thermique spécifique pour caractériser un autre matériau déposée sur la face arrière de la membrane. Nous avons testé ce modèle pour mesurer les propriétés thermiques d'un film de 200 nm de Bi2Te3. Les résultats obtenus sont en excellent accord avec la littérature. Comme le SiN est un matériau isolant, ce modèle est capable de mesurer des films très minces quelle que soit sa nature, isolant, semi conducteur ou métallique.
In order to understand the mechanisms of the heat transport in very thin amorphous films, we have proposed and experimentally demonstrated a new technique to measure the thermal properties of very thin membranes. This technique consists in coupling…
Advisors/Committee Members: Bourgeois, Olivier (thesis director), Jomaah, Jalal (thesis director).
Subjects/Keywords: Phonon; Méthode 3 oméga; Propriétés thermique; Membrane; Matériaux amorphes; Nitrure de silicium; Phonon; 3 omega method; Thermal properties; Membrane; Silicon nitride; Amorphous materials
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ftouni, H. (2013). Transport thermique dans des membranes très minces de SiN amorphe : Thermal transport in very thin amorphous SiN membranes. (Doctoral Dissertation). Université de Grenoble. Retrieved from http://www.theses.fr/2013GRENY046
Chicago Manual of Style (16th Edition):
Ftouni, Hossein. “Transport thermique dans des membranes très minces de SiN amorphe : Thermal transport in very thin amorphous SiN membranes.” 2013. Doctoral Dissertation, Université de Grenoble. Accessed February 27, 2021.
http://www.theses.fr/2013GRENY046.
MLA Handbook (7th Edition):
Ftouni, Hossein. “Transport thermique dans des membranes très minces de SiN amorphe : Thermal transport in very thin amorphous SiN membranes.” 2013. Web. 27 Feb 2021.
Vancouver:
Ftouni H. Transport thermique dans des membranes très minces de SiN amorphe : Thermal transport in very thin amorphous SiN membranes. [Internet] [Doctoral dissertation]. Université de Grenoble; 2013. [cited 2021 Feb 27].
Available from: http://www.theses.fr/2013GRENY046.
Council of Science Editors:
Ftouni H. Transport thermique dans des membranes très minces de SiN amorphe : Thermal transport in very thin amorphous SiN membranes. [Doctoral Dissertation]. Université de Grenoble; 2013. Available from: http://www.theses.fr/2013GRENY046
4.
Li, Dongdi.
Bioinformatics-based approaches to engineer the transmembrane Δ6 desaturase from Micromonas pusilla
.
Degree: 2016, Australian National University
URL: http://hdl.handle.net/1885/110548
► The increased awareness of the health benefits of ω3-long chain polyunsaturated fatty acids (ω3-LCPUFAs) has led to a drastic increase in the consumption of fish-oil…
(more)
▼ The increased awareness of the health benefits of ω3-long chain
polyunsaturated fatty acids (ω3-LCPUFAs) has led to a drastic
increase in the consumption of fish-oil supplements. This has
resulted in environmental concerns and the identification of key
membrane-bound desaturases involved in the biosynthesis of
ω3-LCPUFAs in order to generate a sustainable source of
ω3-LCPUFAs. The Micromonas pusilla Δ6 desaturase (MpΔ6des) is
a membrane-bound desaturase that is specific for ω3-LCPUFA
precursors and acyl-Coenzyme A substrates (acyl-CoAs). The
incorporation of MpΔ6des into the ω3-LCPUFA biosynthesis
pathway allows efficient ω3-LCPUFA production in transgenic
plants. However, little is known of the molecular basis
underlying its
ω3-specificity, stability and acyl-CoAs specificity.
MpΔ6des is relatively challenging in terms of protein
engineering targets in that there is no molecular structure
available, it cannot be expressed in easily manipulated
prokaryotic systems such as Escherichia coli, and the activity
cannot be rapidly screened via the conventional techniques. Thus,
computational, structure-based, protein design and
high-throughput directed evolution could not be used. To overcome
the technical hurdles, we have applied bioinformatics-based
techniques (consensus mutagenesis, ancestral protein
reconstruction and sequence similarity networks) to engineer
MpΔ6des and to better define the sequence-structure-function
relationship of proteins within the desaturase superfamily.
Consensus mutagenesis of MpΔ6des (Chapter 2) demonstrated that
it is possible to modulate the ω3/ω6-specificity of MpΔ6des
semi-independently. The geometry of the substrate-binding pocket
of MpΔ6des was not only influenced by the residues located in
the substrate-binding cavity, but also by distal residues,
possibly through intramolecular interaction networks.
An ancestral algal front-end Δ6 desaturase (ANC175) was inferred
(Chapter 3), which resembles the properties of the progenitor of
the algal Δ6 desaturases. The comparison between ANC175 and
contemporary desaturases indicated that the divergence of the
ω3/ω6-specificity of algal Δ6 desaturases is associated with
the environmental differences seen in the habitats of the
different algal species.
Chapter 4 describes a bioinformatics analysis of the desaturase
superfamily, showing that the four major desaturase subfamilies
(the first desaturases, methyl-end desaturases, front-end
desaturases and Δ4 sphingolipid desaturases) are structurally
and functionally distinct. Conserved motif analysis of the
front-end desaturases suggested that two cytosolic regions (a
loop between AH1 and H2, and the cytosolic side of TM3) play
crucial roles in determining the substrate head-group specificity
of the front-end desaturase.
Altogether, this thesis promotes a more…
Subjects/Keywords: Membrane-bound desaturase;
protein engineering;
omega-3 polyunsaturated fatty acids
…of membrane-bound desaturases ........................................................ 97… …4.3.1
The sequence-structure-function relationships of all known membrane bound
desaturases… …the function of membrane proteins and their related cellular functions.
Highly unsaturated… …plant sources and the discovery and characterization
of many membrane-bound desaturases… …x28;10). The membrane-bound desaturases have been
the focus of many studies into the…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, D. (2016). Bioinformatics-based approaches to engineer the transmembrane Δ6 desaturase from Micromonas pusilla
. (Thesis). Australian National University. Retrieved from http://hdl.handle.net/1885/110548
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):
Li, Dongdi. “Bioinformatics-based approaches to engineer the transmembrane Δ6 desaturase from Micromonas pusilla
.” 2016. Thesis, Australian National University. Accessed February 27, 2021.
http://hdl.handle.net/1885/110548.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Li, Dongdi. “Bioinformatics-based approaches to engineer the transmembrane Δ6 desaturase from Micromonas pusilla
.” 2016. Web. 27 Feb 2021.
Vancouver:
Li D. Bioinformatics-based approaches to engineer the transmembrane Δ6 desaturase from Micromonas pusilla
. [Internet] [Thesis]. Australian National University; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1885/110548.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Li D. Bioinformatics-based approaches to engineer the transmembrane Δ6 desaturase from Micromonas pusilla
. [Thesis]. Australian National University; 2016. Available from: http://hdl.handle.net/1885/110548
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Linnaeus University
5.
Areda, Martha.
The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids.
Degree: Chemistry and Biomedical Sciences, 2016, Linnaeus University
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55601
► Ever since the emergence of the hypothesis that linked the aetiology of schizophrenia with abnormal membrane phospholipids composition, an increasing number of evidences have…
(more)
▼ Ever since the emergence of the hypothesis that linked the aetiology of schizophrenia with abnormal membrane phospholipids composition, an increasing number of evidences have suggested reduced membrane polyunsaturated fatty acids in patients with schizophrenia. This has led to a conduct of several studies to evaluate the efficacy of omega-3 fatty acid supplement in the modification of membrane phospholipids and treatment of schizophrenia. The two main omega-3 fatty acid classes, EPA and DHA, play a vital role in membranes. This project work reviews omega-3 fatty acid studies and summarizes their outcomes. Eight original articles (nine studies) were reviewed. Six out of nine studies measured RBC membrane fatty acids levels and all six studies reported a significant increase in EPA after EPA supplement. Two studies reported increased DHA post omega-3 fatty acid and DHA supplement, respectively. One study observed a dose-dependent increment in DHA after EPA supplement. Improved symptoms were observed in seven studies, while one study found a worsening of symptoms in patients with low baseline PUFA. Moreover, out of the six studies that evaluated the correlation between symptom change and membrane fatty acids change, three studies observed a correlation between increased EPA and symptom improvement. One study reported an increased AA associated with improved symptoms, in contrast to another study, which found a correlation between increased AA and worsened symptoms. The conclusion from this project work is that EPA supplement can increase the EPA levels in membranes; however, its therapeutic effect in schizophrenia requires further investigation using larger studies.
Ända sedan tillkomsten av hypotesen som länkade etiologin av schizofreni med onormala sammansättningar av membranfosfolipider, har bevis för nedsatt membranfettsyror hos patienter med schizofreni ökat. Detta har lett till genomförandet av flera studier för att utvärdera effekten av omega-3 supplement i modifieringen av membranfosfolipider och i behandling av schizofreni. De två viktigaste omega-3 klasserna, EPA och DHA, spelar en viktig roll i membran. Detta projektarbete granskar de omega-3 studierna och sammanfattar deras resultat. Åtta originalartiklar (nio studier) granskades. Sex av nio studier mätte nivåer av RBC membranfettsyror och alla sex studierna rapporterade en signifikant ökning av EPA efter EPA behandling. Två studier rapporterade ökad DHA efter omega-3 och DHA behandling, respektive. En studie observerade en dosberoende ökning i DHA efter EPA behandling. Förbättrade symtom observerades i sju studier, medan en studie fann en försämring av symtom hos patienter med låg baseline PUFA. Av de sex studier som utvärderade sambandet mellan symtomförändring och förändring i membranfettsyror, hittade två studier samband mellan ökad EPA och symtomförbättring. En studie rapporterade en ökad AA i samband med förbättrade symtom, i motsats till en annan studie, som fann ett samband mellan ökad AA och försämrade symtom. Slutsatsen från detta…
Subjects/Keywords: Schizophrenia; omega-3; membrane lipids; PUFA; polyunsaturated fatty acids; EPA; DHA; Eicosapentaenoic Acid; Docosahexaenoic Acid; typical antipsychotics; atypical antipsychotics; Other Health Sciences; Annan hälsovetenskap
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Areda, M. (2016). The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids. (Thesis). Linnaeus University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55601
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):
Areda, Martha. “The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids.” 2016. Thesis, Linnaeus University. Accessed February 27, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55601.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Areda, Martha. “The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids.” 2016. Web. 27 Feb 2021.
Vancouver:
Areda M. The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids. [Internet] [Thesis]. Linnaeus University; 2016. [cited 2021 Feb 27].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55601.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Areda M. The role of omega-3 fatty acids in the treatment of schizophrenia through modification of membrane phospholipids. [Thesis]. Linnaeus University; 2016. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55601
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
6.
Kazemi, Amir Sadegh.
Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications.
Degree: PhD, 2018, McMaster University
URL: http://hdl.handle.net/11375/23404
► Membrane filtration processes are widely utilized across different industrial sectors for biological and environmental separations. Examples of the former are sterile filtration and protein fractionation…
(more)
▼ Membrane filtration processes are widely utilized across different industrial sectors for biological and environmental separations. Examples of the former are sterile filtration and protein fractionation via microfiltration (MF) and ultrafiltration (UF) while drinking water treatment, tertiary treatment of wastewater, water reuse and desalination via MF, UF, nanofiltration (NF) and reverse-osmosis (RO) are examples of the latter. A common misconception is that the performance of membrane separation is solely dependent on the membrane pore size, whereas a multitude of parameters including solution conditions, solute concentration, presence of specific ions, hydrodynamic conditions, membrane structure and surface properties can significantly influence the separation performance and the membrane’s fouling propensity. The conventional approach for studying filtration performance is to use a single lab- or pilot-scale module and perform numerous experiments in a sequential manner which is both time-consuming and requires large amounts of material. Alternatively, high-throughput (HT) techniques, defined as the miniaturized version of conventional unit operations which allow for multiple experiments to be run in parallel and require a small amount of sample, can be employed. There is a growing interest in the use of HT techniques to speed up the testing and optimization of membrane-based separations. In this work, different HT screening approaches are developed and utilized for the evaluation and optimization of filtration performance using flat-sheet and hollow-fiber (HF) membranes used in biological and environmental separations. The effects of various process factors were evaluated on the separation of different biomolecules by combining a HT filtration method using flat-sheet UF membranes and design-of-experiments methods. Additionally, a novel HT platform was introduced for multi-modal (constant transmembrane pressure vs. constant flux) testing of flat-sheet membranes used in bio-separations. Furthermore, the first-ever HT modules for parallel testing of HF membranes were developed for rapid fouling tests as well as extended filtration evaluation experiments. The usefulness of the modules was demonstrated by evaluating the filtration performance of different foulants under various operating conditions as well as running surface modification experiments. The techniques described herein can be employed for rapid determination of the optimal combination of conditions that result in the best filtration performance for different membrane separation applications and thus eliminate the need to perform numerous conventional lab-scale tests. Overall, more than 250 filtration tests and 350 hydraulic permeability measurements were performed and analyzed using the HT platforms developed in this thesis.
Thesis
Doctor of Philosophy (PhD)
Membrane filtration is widely used as a key separation process in different industries. For example, microfiltration (MF) and ultrafiltration (UF) are used for sterilization and…
Advisors/Committee Members: Latulippe, David, Chemical Engineering.
Subjects/Keywords: Membrane filtration; Ultrafiltration; Downstream bio-processing; High-throughput (HT) testing; Wastewater treatment; Hollow-fiber membranes; Humic acids; High-throughput filtration; Design-of-experiments (DOE); Process optimization; Microscale filtration; Microfluidic flow control system; Stirred well filtration; SWF; High-throughput hollow-fiber module; HT-HF; Constant TMP; Constant flux; Multi-modal filtration; Bioseparation; MMFC; Microscale parallel-structured, cross-flow filtration; MS-PS-CFF; PEG; Dextran; FITC-Dextran; BSA; DNA; IgG; α-lactalbumin; Biomolecule separation; Module hydrodynamics; Concentration polarization; Membrane fouling; Micromixing; Omega™ membrane; Microscale processing; Fouling test; PVDF membrane; Surface modification; Polydopamine; Membrane cleaning; Membrane backwashing; Sodium alginate; Polyethersulfone; PES; Hydraulic permeability; Membrane permeability; ZeeWeed® membrane; Filtration ionic strength; Filtration pH; Solution conditions; Water treatment; Environmental separations; Biological separations
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kazemi, A. S. (2018). Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications. (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/23404
Chicago Manual of Style (16th Edition):
Kazemi, Amir Sadegh. “Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications.” 2018. Doctoral Dissertation, McMaster University. Accessed February 27, 2021.
http://hdl.handle.net/11375/23404.
MLA Handbook (7th Edition):
Kazemi, Amir Sadegh. “Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications.” 2018. Web. 27 Feb 2021.
Vancouver:
Kazemi AS. Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications. [Internet] [Doctoral dissertation]. McMaster University; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/11375/23404.
Council of Science Editors:
Kazemi AS. Development of High-throughput Membrane Filtration Techniques for Biological and Environmental Applications. [Doctoral Dissertation]. McMaster University; 2018. Available from: http://hdl.handle.net/11375/23404
7.
Kinnun, Jacob Jerald.
Solid-state NMR spectroscopy applied to model membranes: effects of polyunsaturated fatty acids.
Degree: 2018, IUPUI
URL: http://hdl.handle.net/1805/16931
► Indiana University-Purdue University Indianapolis (IUPUI)
Omega-3 polyunsaturated fatty acids (n-3 PUFAs) relieve the symptoms of a wide variety of chronic inflammatory disorders. Typically, they must…
(more)
▼ Indiana University-Purdue University Indianapolis (IUPUI)
Omega-3 polyunsaturated fatty acids (n-3 PUFAs) relieve the symptoms of a wide variety of chronic inflammatory disorders. Typically, they must be obtained in the diet from sources such as fish oils. Docosahexaenoic acid (DHA) is one of these n-3 PUFAs. As yet the structural mechanism responsible for the health benefits within the body is not completely understood. One model that has emerged from biochemical and imaging studies of cells suggests that n-3 PUFAs are taken up into phospholipids in the plasma membrane. Thus the focus here is on the plasma membrane as a site of potential structural modification by DHA. Within cellular membranes, the huge variety of molecules (called lipids) which constitute the membrane suggest inhomogeneous mixing, thus domain formation. One potential domain of interest is called the lipid raft, which is primarily composed of sphingomyelin (SM) and cholesterol (chol). Here the molecular organization of [2H31]-N-palmitoylsphingomyelin (PSM-d31) mixed with 1-palmitoyl-2-docosahexaenoylphosphatylcholine (PDPC) or 1-palmitoyl-2-oleoylphosphatidylcholine (POPC), as a monounsaturated control, and cholesterol (chol) (1:1:1 mol) in a model membrane was examined by solid state 2H NMR spectroscopy.
Solid state 2H NMR spectroscopy extracts details of molecular orientation and anisotropy of molecular reorientation by analysis of the lineshape. This essentially non-invasive technique allows for a direct measurement of dynamics in bulk materials which has been extensively applied to biological materials. It is a niche area of NMR for which standard software often lack necessary features. Two software programs, “EchoNMR processor” and “EchoNMR simulator”, collectively known as “EchoNMR tools”, that were developed to quickly process and analyze one-dimensional solid-state NMR data, will be described along with some theoretical background of the techniques used. EchoNMR tools has been designed with a focus on usability and the open-source mindset. This is achieved in the in the MATLAB® programming environment which allows for the development of the graphical user interfaces and runs as an interpreter which allows the code to be open-source. The research described here on model membranes demonstrates the utility of the software.
The NMR spectra for PSM-d31 in mixtures with PDPC or POPC with cholesterol were interpreted in terms of the presence of nano-sized SM-rich/chol-rich (raft-like) and PC-rich/chol-poor (non-raft) domains that become larger when POPC was replaced by PDPC. An increase in the differential in order and/or thickness between the two types of domains is responsible. The observation of separate signals from PSM-d31, and correspondingly from [3α-2H1]cholesterol (chol-d1) and 1-[2H31]palmitoyl-2-docosahexaenoylphosphatidylcholine (PDPC-d31), attributed to the raft-like and non-raft domains enabled the determination of the composition of the domains. Most of the SM (84%) and cholesterol (88%) was found in the raft-like domain.…
Advisors/Committee Members: Wassall, Stephen R..
Subjects/Keywords: Membrane Biophysics; Polyunsaturated Fatty Acids; Nuclear Magnetic Resonance; Omega-3 Fatty Acids; Membrane Rafts; Cellular Membranes; Deuterium NMR
…lipid in
the mixed membrane. As shown, the majority of each lipid species resides
within the… …Effects of
Polyunsaturated Fatty Acids
Committee Chair: Stephen R. Wassall
Omega-3… …phospholipids in the plasma membrane.
Thus the focus here is on the plasma membrane as a site of… …x28;called lipids) which
constitute the membrane suggest inhomogeneous mixing, thus… …1:1 mol) in a model
membrane was examined by solid state 2H NMR spectroscopy.
Solid…
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APA (6th Edition):
Kinnun, J. J. (2018). Solid-state NMR spectroscopy applied to model membranes: effects of polyunsaturated fatty acids. (Thesis). IUPUI. Retrieved from http://hdl.handle.net/1805/16931
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):
Kinnun, Jacob Jerald. “Solid-state NMR spectroscopy applied to model membranes: effects of polyunsaturated fatty acids.” 2018. Thesis, IUPUI. Accessed February 27, 2021.
http://hdl.handle.net/1805/16931.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kinnun, Jacob Jerald. “Solid-state NMR spectroscopy applied to model membranes: effects of polyunsaturated fatty acids.” 2018. Web. 27 Feb 2021.
Vancouver:
Kinnun JJ. Solid-state NMR spectroscopy applied to model membranes: effects of polyunsaturated fatty acids. [Internet] [Thesis]. IUPUI; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/1805/16931.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kinnun JJ. Solid-state NMR spectroscopy applied to model membranes: effects of polyunsaturated fatty acids. [Thesis]. IUPUI; 2018. Available from: http://hdl.handle.net/1805/16931
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
8.
Ravacci, Graziela Rosa.
Desestruturação de lipid rafts por ácido docosaexaenoico (DHA) induz apoptose em células epiteliais luminais da glândula mamária humana transformadas pela superexpressão de HER-2.
Degree: PhD, Oncologia, 2013, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/5/5155/tde-19042013-114655/
;
► A superexpressão de receptores HER-2 é anormalidade celular de grande relevância clínica no câncer de mama. Ela ocorre em aproximadamente 30% de carcinomas de mama…
(more)
▼ A superexpressão de receptores HER-2 é anormalidade celular de grande relevância clínica no câncer de mama. Ela ocorre em aproximadamente 30% de carcinomas de mama incluindo lesões pré-neoplásicas e malignas, e está associada a prognóstico desfavorável. A hiperativação dos receptores HER-2, consequência natural de sua superexpressão, promove proliferação celular aberrante e tumorigênese. Admite-se que a ativação e envio de sinais via HER-2 possa acontecer quando estes receptores se encontram em compartimentos específicos da membrana celular, os lipid rafts. Assim, um número maior de HER-2 poderia implicar em maior quantidade de lipis rafts. Para testar essa hipótese, usamos modelo de transformação oncogênica que nos permitiu avaliar, especificamente, os efeitos da superexpressão de HER-2 e identificar a quantidade de lipid rafts. Para isso utilizamos a linhagem celular HB4a, derivada de célula epitelial luminal do tecido mamário humano normal com baixa expressão de HER-2; e a linhagem HB4aC5.2, um clone derivado da HB4a, que superexpressa receptores HER-2. Nas células HB4aC5.2, a superexpressão de HER-2 foi acompanhada pelo aumento dos lipid rafts na membrana celular, bem como, hiperativação de sinais de sobrevivência, proliferação (aumento da ativação de proteínas Akt e Erk1/2, respectivamente), e taxa de proliferação celular duas vezes mais rápida que a linhagem normal HB4a. Adicionalmente, a superexpressão de HER-2 foi associada com aumento da lipogênese celular (fenótipo lipogênico), dependente do aumento de ativação da enzima FASN e da superexpressão de DEPTOR. A FASN é responsável pela síntese de palmitato, utilizado para formação de lipid rafts. A superexpressão de DEPTOR, por modular a atividade transcricional de PPAR?, pode evitar a lipotoxicidade do excesso de palmitato. Além disso, DEPTOR, por sua capacidade em reduzir atividade do complexo mTORC1, contribui para sobrevivência celular dependente da proteína Akt. Em continuidade, consideramos, como segunda hipótese, que a desestruturação de lipid rafts poderia influenciar negativamente a ativação dos receptores HER-2. Para isso tratamos, as mesmas linhagens celulares anteriormente descritas, com ácido docosaexaenoico (DHA), um tipo de ácido graxo ômega-3. Nossos resultados mostraram que, nas células HB4aC5.2, o tratamento com DHA desestruturou os lipid rafts, inibiu a sinalização iniciada pelos receptores HER-2 ( diminuição da ativação das proteínas Akt, Erk1/2, FASN, atividade transcricional de PPAR? e expressão de DEPTOR) e reverteu o fenótipo lipogênico. Adiciona-se que essas modificações celulares e moleculares foram acompanhadas por indução significativa de morte e apoptose. As mesmas alterações não foram observadas nas células normais HB4a. Em conclusão, o presente estudo reforça a associação entre a presença de HER-2 e lipid rafts. Adicionalmente aponta que a desestruturação de lipid rafts por DHA reduz a sinalização de HER-2. Por fim, sugere que distúrbios em lipid rafts, induzidos por DHA, possam representar ferramenta útil no controle da…
Advisors/Committee Members: Waitzberg, Dan Linetzky.
Subjects/Keywords: Ácidos graxos ômega 3; Apoptose; Apoptosis; Breast neoplasias; Epidermal growth factor receptor HER-2; Fatty acids omega-3; Membrane microdomains; Microdomínios da membrana; Neoplasias da mama; Receptor do fator de crescimento epidérmico HER-2; Signal transduction; Transdução de sinal
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ravacci, G. R. (2013). Desestruturação de lipid rafts por ácido docosaexaenoico (DHA) induz apoptose em células epiteliais luminais da glândula mamária humana transformadas pela superexpressão de HER-2. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/5/5155/tde-19042013-114655/ ;
Chicago Manual of Style (16th Edition):
Ravacci, Graziela Rosa. “Desestruturação de lipid rafts por ácido docosaexaenoico (DHA) induz apoptose em células epiteliais luminais da glândula mamária humana transformadas pela superexpressão de HER-2.” 2013. Doctoral Dissertation, University of São Paulo. Accessed February 27, 2021.
http://www.teses.usp.br/teses/disponiveis/5/5155/tde-19042013-114655/ ;.
MLA Handbook (7th Edition):
Ravacci, Graziela Rosa. “Desestruturação de lipid rafts por ácido docosaexaenoico (DHA) induz apoptose em células epiteliais luminais da glândula mamária humana transformadas pela superexpressão de HER-2.” 2013. Web. 27 Feb 2021.
Vancouver:
Ravacci GR. Desestruturação de lipid rafts por ácido docosaexaenoico (DHA) induz apoptose em células epiteliais luminais da glândula mamária humana transformadas pela superexpressão de HER-2. [Internet] [Doctoral dissertation]. University of São Paulo; 2013. [cited 2021 Feb 27].
Available from: http://www.teses.usp.br/teses/disponiveis/5/5155/tde-19042013-114655/ ;.
Council of Science Editors:
Ravacci GR. Desestruturação de lipid rafts por ácido docosaexaenoico (DHA) induz apoptose em células epiteliais luminais da glândula mamária humana transformadas pela superexpressão de HER-2. [Doctoral Dissertation]. University of São Paulo; 2013. Available from: http://www.teses.usp.br/teses/disponiveis/5/5155/tde-19042013-114655/ ;
9.
Gerling, Christopher.
The Effects of Omega-3 Supplementation on Human Skeletal Muscle Sarcolemmal and Mitochondrial Membrane Fatty Acid Composition and Whole Body Substrate Oxidation.
Degree: MS, Department of Human Health and Nutritional Sciences, 2013, University of Guelph
URL: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/7478
► This thesis investigated the effects of omega-3 supplementation (2.0 g/day EPA + 1.0 g/day DHA) for 12 weeks on human skeletal muscle sarcolemmal and mitochondrial…
(more)
▼ This thesis investigated the effects of
omega-3 supplementation (2.0 g/day EPA + 1.0 g/day DHA) for 12 weeks on human skeletal muscle sarcolemmal and mitochondrial
membrane fatty acid (FA) composition and whole body energy expenditure in young healthy males. Supplementation resulted in significant incorporation of EPA and DHA into sarcolemmal and mitochondrial membranes, with an increase in total unsaturation of mitochondrial membranes. The incorporation profile of the sarcolemma and mitochondria differed, with the mitochondria mimicking changes in whole muscle. There were no changes in the protein content of mitochondrial and selected proteins involved in energy metabolism, except for a significant increase in the long form of UCP3. Despite changes in
membrane FA compositions, there were no changes in whole body substrate oxidation at rest or during exercise. These data demonstrate that
omega-3 supplementation for 12 weeks altered the FA composition of sarcolemmal and mitochondrial membranes in human skeletal muscle.
Advisors/Committee Members: Spriet, Lawrence (advisor).
Subjects/Keywords: Omega-3; Metabolism; Skeletal Muscle; Substrate Oxidation; Eicosapentaenoic acid; Docosahexaenoic acid; Membrane Fatty Acid Composition
…omega-3 supplementation
21
differently. It is therefore important to isolate each membrane… …of omega-3s for 7 weeks increased the DHA content in the outer
mitochondrial membrane, and… …effects of omega-3 supplementation on an
individual membrane in skeletal muscle, and how this… …LIST OF TABLES
Table 1. Subject characteristics before and after 12 weeks of omega-3 or… …41
Table 2. Serum fatty acid composition before and after 12 weeks of omega-3…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gerling, C. (2013). The Effects of Omega-3 Supplementation on Human Skeletal Muscle Sarcolemmal and Mitochondrial Membrane Fatty Acid Composition and Whole Body Substrate Oxidation. (Masters Thesis). University of Guelph. Retrieved from https://atrium.lib.uoguelph.ca/xmlui/handle/10214/7478
Chicago Manual of Style (16th Edition):
Gerling, Christopher. “The Effects of Omega-3 Supplementation on Human Skeletal Muscle Sarcolemmal and Mitochondrial Membrane Fatty Acid Composition and Whole Body Substrate Oxidation.” 2013. Masters Thesis, University of Guelph. Accessed February 27, 2021.
https://atrium.lib.uoguelph.ca/xmlui/handle/10214/7478.
MLA Handbook (7th Edition):
Gerling, Christopher. “The Effects of Omega-3 Supplementation on Human Skeletal Muscle Sarcolemmal and Mitochondrial Membrane Fatty Acid Composition and Whole Body Substrate Oxidation.” 2013. Web. 27 Feb 2021.
Vancouver:
Gerling C. The Effects of Omega-3 Supplementation on Human Skeletal Muscle Sarcolemmal and Mitochondrial Membrane Fatty Acid Composition and Whole Body Substrate Oxidation. [Internet] [Masters thesis]. University of Guelph; 2013. [cited 2021 Feb 27].
Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/7478.
Council of Science Editors:
Gerling C. The Effects of Omega-3 Supplementation on Human Skeletal Muscle Sarcolemmal and Mitochondrial Membrane Fatty Acid Composition and Whole Body Substrate Oxidation. [Masters Thesis]. University of Guelph; 2013. Available from: https://atrium.lib.uoguelph.ca/xmlui/handle/10214/7478

East Carolina University
10.
Rockett, Benjamin Drew.
Fish oil disrupts B cell plasma membrane lateral organization and immunological synapse formation.
Degree: PhD, Biochemistry and Molecular Biology, 2012, East Carolina University
URL: http://hdl.handle.net/10342/4108
► Fish oil has immunosuppressive properties that could provide treatment for numerous inflammatory and autoimmune disorders. The primary bioactive components of fish oil, which are the…
(more)
▼ Fish oil has immunosuppressive properties that could provide treatment for numerous inflammatory and autoimmune disorders. The primary bioactive components of fish oil, which are the n-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), can exert differential effects on many cell types in the body. A major limitation in the development of fish oil as a therapeutic is the lack of mechanistic understanding of how fish oil exerts its functional effects. One emerging mechanism is that EPA and DHA have unique biophysical properties that could disrupt the lateral organization of plasma
membrane lipids and proteins critical for signaling and cell-cell communication, such as lipid rafts and the immunological synapse. In this study, we investigate a potential mechanism for this disruption in B cells, a cell type poorly represented in the field of n-3 PUFA research. The central hypothesis for this study was that fish oil disrupts lateral organization of lipid rafts and suppresses downstream B cell function. Using high and low fat fish oil diets in mice, we demonstrated that fish oil dispersed clustering of B cell lipid rafts on a micron scale, and enhanced
membrane molecular order upon cross-linking raft domains. We found that the effects on lipid rafts are primarily driven by DHA and not EPA, and that n-3 PUFAs have a limited influence on non-raft lateral organization. Finally, we show that fish oil suppresses B cell antigen presentation and subsequent CD4+ T cell IL-2 secretion, by disrupting the B cell side of the immunological synapse. Taken together, this work highlights the utility of fish oil, more specifically DHA, as a tool for disrupting plasma
membrane lateral organization. We add to the biochemical understanding of how these fatty acids may disrupt various downstream signaling events and cell-cell interactions. It also emphasizes the importance of the plasma
membrane as a target for suppressing other cellular functions mediated through lipid raft domains. Finally, these studies add B cells as key targets for suppression of antigen presentation in diseases such as autoimmune disorders. Â
Advisors/Committee Members: Shaikh, Saame Raza (advisor).
Subjects/Keywords: Chemistry, Biochemistry; B cells; Lipid rafts; Biochemistry; Biochemical Phenomena; Fish Oils; Fatty Acids, Omega-3; Animals; Th1 Cells; Mice; Interleukin-2; Cell Fractionation; Membrane Microdomains; Fatty Acids, Unsaturated; Eicosapentaenoic Acid; Docosahexaenoic Acids; Immunological Synapses; Models, Animal
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rockett, B. D. (2012). Fish oil disrupts B cell plasma membrane lateral organization and immunological synapse formation. (Doctoral Dissertation). East Carolina University. Retrieved from http://hdl.handle.net/10342/4108
Chicago Manual of Style (16th Edition):
Rockett, Benjamin Drew. “Fish oil disrupts B cell plasma membrane lateral organization and immunological synapse formation.” 2012. Doctoral Dissertation, East Carolina University. Accessed February 27, 2021.
http://hdl.handle.net/10342/4108.
MLA Handbook (7th Edition):
Rockett, Benjamin Drew. “Fish oil disrupts B cell plasma membrane lateral organization and immunological synapse formation.” 2012. Web. 27 Feb 2021.
Vancouver:
Rockett BD. Fish oil disrupts B cell plasma membrane lateral organization and immunological synapse formation. [Internet] [Doctoral dissertation]. East Carolina University; 2012. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10342/4108.
Council of Science Editors:
Rockett BD. Fish oil disrupts B cell plasma membrane lateral organization and immunological synapse formation. [Doctoral Dissertation]. East Carolina University; 2012. Available from: http://hdl.handle.net/10342/4108
11.
Moreira, Ana Vládia Bandeira.
Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6.
Degree: PhD, Bromatologia, 2003, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15072014-150247/
;
► Dentro da perspectiva da utilização de compostos fenólicos como antioxidantes naturais para minimizar os efeitos in vitro e in vivo do processo oxidativo dos lípides…
(more)
▼ Dentro da perspectiva da utilização de compostos fenólicos como antioxidantes naturais para minimizar os efeitos in vitro e in vivo do processo oxidativo dos lípides insaturados, foi realizada a monitoração dietética de duas dietas ricas em lípides das séries ω3 e ω6 e a suplementação de um chá de uma mistura de especiarias, em ratos Wistar, com o objetivo de verificar a influência dos compostos fenólicos, presentes nas especiarias, sobre o metabolismo de ácidos graxos das séries ω3 e ω6. Extratos e frações das especiarias mostarda, canela e erva doce foram obtidos e tiveram suas atividades antioxidantes testadas em sistemas aquoso (cooxidação de substratos com o uso de ácido linoléico/β-caroteno) e lipídico (RANCIMAT) e o perfil de compostos fenólicos identificados e quantificados por CGMS. A partir de uma mistura de especiarias, foi elaborado um chá que foi fornecido aos animais de cada grupo dietético (ω3 e ω6). Após 45 dias de tratamento, os animais foram sacrificados e tiveram seus tecidos coletados para análise de TBARs e do perfil lipídico por CGMS. Todos os extratos das especiarias apresentaram atividade antioxidante equivalente ou superior ao BHT. Foram identificados por CGMS os ácidos fenólicos: catecol, salicílico e caféico. Foi obtido nos tecidos dos animais que o somatório do perfil de ácidos graxos saturados e dos insaturados apresentaram diferença entre os grupos testes e controles. Logo, no tecido cerebral, o EPA foi incorporado apenas no grupo ω3 que recebeu o extrato das especiarias. Já para o DHA, do mesmo grupo dietético, os tecidos hepático e renal também apresentaram incorporação aumentada em relação ao controle. No grupo dietético ω6, destaca-se um aumento no percentual de incorporação do ácido linoléico nos tecidos cardíaco e renal no grupo experimental. Enquanto, para o ácido araquidônico, houve diferença em todos os tecidos. Já, para os resultados da lipoperoxidação, observou-se que todos os tecidos dos animais que receberam o extrato das especiarias apresentaram baixos valores em comparação aos seus respectivos controles. Este estudo também avaliou a ação de compostos fenólicos do chá da mistura das especiarias mostarda, canela e erva doce sobre as enzimas lipoxigenase e cicloxigenase. O extrato da mistura das especiarias a 100 e 200 ppm foi adicionado no meio de reação contendo o substrato e a enzima lipoxigenase 1B da Sigma com 112.000 und/mg. A cicloxigenase foi obtida de vesículas seminais de carneiro e seguiu-se o mesmo protocolo de atividade para a lipoxigenase. Indometacina foi o inibidor utilizado como controle positivo da reação. Observou-se que a 200 ppm, como na concentração do chá (0,02%), a lipoxigenase foi inibida em aproximadamente em 90%. Já para a cicloxigenase, o extrato a 200 ppm resultou numa média de 75% de inibição da atividade da enzima, enquanto que a indomentacina apresentou uma média de 77% de inibição. A absorção aparente do chá das especiarias indicou que os fenólicos presentes na mistura foram absorvidos em média de…
Advisors/Committee Members: Mancini Filho, Jorge.
Subjects/Keywords: Ácidos graxos ômega 3; Ácidos graxos ômega 6; Aditivos alimentares; Antioxidantes; Antioxidants; Composição de membrana; Compostos fenólicos naturais; Eicosanóides; Eicosanoids; Food additives; Membrane Composition; Natural phenolic compounds; Omega 3 fatty acids; Omega 6 fatty acids
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Moreira, A. V. B. (2003). Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15072014-150247/ ;
Chicago Manual of Style (16th Edition):
Moreira, Ana Vládia Bandeira. “Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6.” 2003. Doctoral Dissertation, University of São Paulo. Accessed February 27, 2021.
http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15072014-150247/ ;.
MLA Handbook (7th Edition):
Moreira, Ana Vládia Bandeira. “Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6.” 2003. Web. 27 Feb 2021.
Vancouver:
Moreira AVB. Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6. [Internet] [Doctoral dissertation]. University of São Paulo; 2003. [cited 2021 Feb 27].
Available from: http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15072014-150247/ ;.
Council of Science Editors:
Moreira AVB. Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6. [Doctoral Dissertation]. University of São Paulo; 2003. Available from: http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15072014-150247/ ;
.