Polyunsaturated fatty acid production from novel Thraustochitryd strain using hemp seeds and its antioxidative potential

Author: Trinh Thanh Thanh Nguyen

  • Thesis download: available for open access on 27 May 2023.

Nguyen, Trinh Thanh Thanh, 2022 Polyunsaturated fatty acid production from novel Thraustochitryd strain using hemp seeds and its antioxidative potential, Flinders University, College of Medicine and Public Health

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Abstract

The utilization of microorganisms to produce sustainable bioactive compounds or biofuels has received recent attention due to its potential benefits for human health. It is expected that the modification of microbial growth conditions could induce a higher production of desired bioactive compounds. In this study, a newly isolated marine Thraustochytrid strain S2 was used for polyunsaturated fatty acid (PUFA) production by growing on hemp seed (Cannabis sativa) powder. Considered as functional foods, PUFAs have been demonstrated to assist in maintaining biological functions, improving conditions of health, and effectively reducing risks from severe diseases. The Thraustochytrid strain was able to grow on the study (HS) and market hemp seed (MHS) powder and accumulated polyunsaturated fatty acids. As a result, biomass and total lipid production were remarkably increased after fermentation, particularly when glucose was combined in the fermentation medium. Fatty acid profile analysis of HS, MHS, and commercial hemp seed oil (CHSO) after fermentation resulted in higher production of some essential fatty acids. In addition, the lipid profile of HS and MHS presented significant alpha-linolenic acid (ALA) production, which was not observed in a control study. Several biostimulants applied to the hemp seed crop showed minimal effect on lipid production, but some remarkable changes in some specific FAs were noticed, especially in hemp seeds collected from crops added with complex biostimulants. In addition, HS performed low antioxidant activity when compared to Trolox as a positive control. However, the free radical scavenging effect was doubled after fermentation due to the inherent presence of antioxidant biomolecules in Thraustochytrid. The highest antioxidant activity was observed with the combination of HS and glucose at a high concentration. This study demonstrated that HS is a potential carbon source for enhancing fermentation products of Thraustochytrid in terms of biomass, essential PUFAs, and antioxidative activity.

Keywords: PUFA, Thraustochitryd, hempseeds, microbes, fermentation, biostimulants

Subject: Biotechnology thesis

Thesis type: Masters
Completed: 2022
School: College of Medicine and Public Health
Supervisor: Munish Puri