Utilization of food processing waste by Thraustochytrids

Abstract

Schizochytrium mangrovei KF6, a mangrove thraustochytrid isolate, was evaluated for its docosahexaenoic acid (DHA) production potential in both a glucose yeast extract medium and various food waste. Highest DHA yield was obtained after 4 days of incubation in a glucose medium at 3094 mg/L or 203 mg/g. Waste fermented with 5, mangrovei also yielded DHA in varying quantities: 12.6 mg/g DHA from bread crusts, 7.3 mg/g and 6.2 mg/g respectively from okara powder and brewing grain waste. Analysis of the waste before and after fermentation showed that the simple sugars, fatty acids with 18 carbons, namely stearic (18:0), oleic (18:1) and linoleic (18:2) acids were utilized by S. mangrovei. Yields of DHA from thraustochytrids grown on waste (6.2-12.3 mg/g) were much lower than those grown in glucose yeast extract medium (203 mg/g). This study has shown that thraustochytrids can increase the nutritive value of food waste and such a product may find a use in aquaculture.