Download the full-sized PDF of Antimicrobial activity of flavan-3-ols and oligomeric proanthocyanidins from pea seed coats and grape seeds against food and gut bacteriaDownload the full-sized PDF



Permanent link (DOI):


Export to: EndNote  |  Zotero  |  Mendeley


This file is in the following communities:

Graduate Studies and Research, Faculty of


This file is in the following collections:

Theses and Dissertations

Antimicrobial activity of flavan-3-ols and oligomeric proanthocyanidins from pea seed coats and grape seeds against food and gut bacteria Open Access


Other title
gut microbiota
oligomeric proanthocyanidins
High speed counter current chromatography
Type of item
Degree grantor
University of Alberta
Author or creator
Solis Ares, Maria
Supervisor and department
Ganzle, Michael (ALES)
Examining committee member and department
Willing, Ben (ALES)
Ozga, Jocelyn (ALES)
Curtis, Jonathan (Chemistry)
Jeon, Byeong Hwa (Public health)
Department of Agricultural, Food, and Nutritional Science
Food Science and Technology
Date accepted
Graduation date
2017-11:Fall 2017
Master of Science
Degree level
Proanthocyanidins and their monomeric subunits flavan-3-ols belong to the polyphenol group of flavonoids. They have been proposed to exert health promoting effects against cancer, Type 2 diabetes and coronary disease among other conditions. These health promoting effects are believed to be related to the modulation of gastric transit, the inhibition of digestive enzymes, the modulation of the gut microbiota and the direct health promoting effects upon absorption, but the mechanisms remain unknown. This thesis focuses on the properties of modulation of gut microbiota as well as the inhibition of digestive enzymes. The proanthocyanidin extracts from pea seed coats were analyzed using UPCL-ESI-MS prior to their separation using High Speed Counter Current Chromatography (HSCCC), a technique with several advantages over other chromatographic methods. No flavan-3-ols or proanthocyanidins were identified in these extracts, hypothesizing that these molecules underwent oxidation and are now highly polymerized. Commercial grape seed extract was selected as the raw material for the separation of proanthocyanidins by their degree of polymerization. It was possible to isolate 3 fractions: Fraction I with trimeric proanthocyanidins, Fraction II with trimeric and dimeric proanthocyanidins and Fraction III with dimeric proanthocyanidins as well as a polymeric proanthocyanidin fraction; flavan-3-ols were commercially available. The antimicrobial effect of flavan-3-ols increased with the number of hydroxyl groups in the molecule, specifically by OH groups and gallate moieties located on the B ring of the monomer. The antimicrobial effect of oligomeric proanthocyanidins from grape seed extract does not increase with the length of the oligomer. The enzyme inhibition properties of flavan-3-ols is increased with the number of hydroxyl groups present in the monomer, but there was no evidence that this trait increased with the length of the oligomer in the case of grape seed proanthocyanidins. Gut microbiota modulation and enzyme inhibition properties of flavan-3-ols and proanthocyanidins cannot entirely explain the health promoting effects exerted by these compounds. Therefore, further research needs to be done in the modulation of the gastric transit by flavan-3-ols and oligomeric proanthocyanidins as well as their direct effects upon absorption; the determination of the antimicrobial effect of flavan-3-ol metabolites will be useful for a more thoroughly understanding of the modulation of gut microbiota by flavan-3-ols and proanthocyanidins.
This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for the purpose of private, scholarly or scientific research. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
Citation for previous publication

File Details

Date Uploaded
Date Modified
Audit Status
Audits have not yet been run on this file.
File format: pdf (PDF/A)
Mime type: application/pdf
File size: 1930246
Last modified: 2017:11:08 17:14:41-07:00
Filename: SolisAres_Maria_201709_MSc.pdf
Original checksum: c7a1b9f03c666557319a2c33615ee8a9
Activity of users you follow
User Activity Date