Schizochytrium sp. S31 was shown to have potential for production of the functional food ingredients docosahexaenoic acid (DHA) and astaxanthin, with coproduction of biodiesel. Biomass and lipid levels were greater with glycerol than with glucose as carbon source. Addition of propyl gallate or butylated hydroxytoluene to the media resulted in increased biomass and lipid levels, with propyl gallate being the more effective of the two antioxidants. Medium supplementation with propyl gallate at 0.03% and glycerol as the carbon source resulted in enhanced biomass productivity (28.50 g L-1), lipid accumulation (24.87 g L-1) and astaxanthin levels (452.26 μg L-1).