Removal of Cyanogenic Glycosides in Whole Flaxseed via Lactobacillaceae Fermentation

Flaxseed is considered as a functional food because it enriches with omega-3, dietary fiber, lignan and protein. Whole flaxseed can be added to bakery products including breads, buns, and cookies to increase the health benefits of these foods. However, flaxseed contains cyanogenic glycosides (CGs), including linamarin, linustatin, lotaustralin and neolinustatin. Cyanogenic glycosides are metabolized to cyanohydrins by the action of the enzymes beta-glucosidase and hydroxynitrile lyase which first cleave glucose from CG then release hydrogen cyanide (HCN) from the cyanohydrin, respectively. Hydrogen cyanide can affect mammalian respiratory systems and can also influence nutrient absorption from food. Thus, CGs should be removed from flaxseed. In this study, whole flaxseed (35 g, 340 g and 1 kg) was fermented with a consortium culture of Lactobacillaceae at 30 °C over 72 h. Concentrations of CGs (total HCN, linustatin and neolinustatin), percent oil, percent secoisolariciresinol diglucoside (SDG) and fatty acid profiles in whole flaxseed were measured using 1H-NMR. The results showed that CGs decreased to below detection limits over 72 h for both bench-scale and scale-up bacterial fermentation experiments. The consortium culture was largely from members of the family Lactobacillaceae. Furthermore, fatty acid composition remained unchanged during fermentation, while concentration of flaxseed oil and SDG significantly improved from 41.20% to 54.40% and 2.26% to 4.13%, respectively, after fermentation. Altogether, whole flaxseed treated via Lactobacillaceae fermentation was depleted in CGs, while nutritional compounds were maintained.

Name thesis:degree_name

Master of Science (M.Sc.)

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Biological Engineering

Grantor

University of Saskatchewan

Year dc:date.issued

2023

Author dc:creator

• Huang, Chao

Advisors dc:contributor.advisor

• Meda, Venkatesh
• Reaney, Martin

Committee members dc:contributor.committeemember

• Tabil, Lope
• Acharya, Bishnu
• Newkirk, Rex

• Cyanogenic glycosides, Removal, Whole flaxseed, Fermentation, Lactobacillaceae

Language dc:language.iso

en

Handle dc:identifier.uri

https://hdl.handle.net/10388/14722

OAI identifier oai:identifier

oai:harvest.usask.ca:10388/14722