Evaluation of liquid residues from beer and potato processing for the production of docosahexaenoic acid (C22:6n-3, DHA) by native thraustochytrid strains

Abstract

Liquid residues from beer (RB) and potato (RP) processing were evaluated as carbon sources for the production of docosahexaenoic acid (C22:6n-3, DHA) by two native Thraustochytriidae sp., M12-X1 and C41, in shaking flask experiments. Results were compared with those obtained in the fermentations of glucose, maltose, soluble starch and ethanol. Both strains produced the highest biomass concentration (2.3 g/L) in the fermentation of RB supplemented with nitrogen sources [yeast extract (YE) and monosodium glutamate (MSG)]. DHA content in the fatty acids produced by the native thraustochytrids was dependent on the fermented carbon source; the fatty acids from biomass grown on carbon sources that permitted a lower growth rate contained more DHA. The highest DHA productivity [55.1 mg/(day L)] was obtained in the fermentation of RB-YE-MSG by M12-X1 strain. In this medium, M12-X1 strain grew at a specific growth rate of 0.014 h -1 and total fatty acid content in the biomass was 41.3%. Production of DHA by M12-X1 strain followed a non-growth rate associated pattern and DHA content in the biomass decreased significantly after growth ceased.

Propyl gallate and butylated hydroxytoluene influence the accumulation of saturated fatty acids, omega-3 fatty acid and carotenoids in thraustochytrids

“…Thraustochytrids are able to efficiently utilize a broad spectrum of carbon sources, and so can potentially be fermented using low cost carbon sources Johnson & Wen, 2009;Pyle, Garcia, & Wen, 2008;Quilodrán, Hinzpeter, Quiroz, & Shene, 2009). Propyl gallate, a well-known antioxidant used in the food industry as a preservative, is also reported to block pyruvate transport into mitochondria and is also a non-competitive inhibitor of Δ5 and Δ6 desaturase enzymes, potentially changing the fatty acid profile in microorganisms including thrautochytrids (Eler, Peralta, & Bracht, 2009;Kawashima, Akimoto, Shirasaka, & Shimizu, 1996).Therefore, we chose to study of effects of propyl gallate, and the antioxidant butylated hydroxytoluene (BHT), on thraustochytrids fermentation to determine the impact on DHA productivity, using the strain designated Schizochytrium sp.…”

Bioremediation of piggery slaughterhouse wastewater using the marine protist, Thraustochytrium kinney VAL-B1

“…For example, in the study carried out by Yamasaki et al [17] when using shochu residue to produce PUFAs and xanthophylls using a Schizochytrium sp strain, COD of the residue was reduced by 35% (initial COD: 79,000 mg L −1 ) after a 5-day fermentation. On the other hand, in the study carried out by Quilodrán et al [18] , COD of the beer residue decreased by 27.6% after a 7-day fermentation by T. kinney M12-X1.…”

“…The highest biomass production (3.55 g L −1 ) was reached when glucose was added to the medium with FeCl 3 ×6H 2 0 (at 50 mg L −1 ), whereas cultures without glucose supplementation resulted in less biomass production (1.92 g L −1 ) at the same FeCl 3 ×6H 2 O concentration, which was similar to the obtained in fermentations with YE-MSG-Gluc without the supplementation of FeCl 3 ×6H 2 O (1.75 g L −1 ). In addition, in the study conducted by Quilodrán et al [18] , the nitrogen source (MSG) had a greater influence on biomass production by M12-X1 strain in medium with beer residue sources (MSG), since the highest biomass production was reached in fermentations with the beer residue supplemented with YE-GMS (2.3 g L −1 ), whereas the biomass obtained in fermentations for the same residue without the addition of MSG was 1.7 g L −1 . This behavior agrees with Iida et al [40] , suggesting that GMS is one of most important components in culture medium for the growth of these microorganisms.…”

“…In addition, it has been demonstrated that THs are able to use different residues as a substrate for their growth and biomass production, for example, okara, a residue of soy milk [13] , crude glycerol [14] , coconut water [15] and bread crumbs [16] . However, since most of the investigations are focused on the biotechnological application of the microorganism (PUFAs production), the bioremediation potential of THs has been scarcely evaluated, and there are few studies in which researchers observed that THs can act favorably on the pollutant load of residues and decrease the concentration of physicochemical parameters, such as COD [17] , [18] , total nitrogen, nitrate, ammonia and phosphate content on different residues of food industry [19] , [20] . Thus, the aim of this work was to evaluate the bioremediation ability of a native strain of TH in piggery SWW.…”

Microbial Oils and Fatty Acids: Effect of Carbon Source on Docosahexaenoic Acid (C22:6 N-3, Dha) Production by Thraustochytrid Strains

“…M12-X1 (similar to Thraustochytrium kinnei, 99% identity) and Thraustochytriidae sp. C41 (similar to Schyzochytrium minutum, 97% identity) in shaking flasks (Quilodrán et al, 2009). For both strains, RB supplemented with yeast extract and monosodium glutamate, at 2 g L -1…”