Effect of malate on docosahexaenoic acid production from Schizochytrium sp. B4D1

AbstractBackgroundMalate involves in the citrate/malate and transhydrogenase cycles to provide precursors for docosahexaenoic acid (DHA) synthesis. The optimal strategy was investigated for increasing DHA production in Schizochytrium species during fermentation.ResultsDHA production increased by 47% and reached 5.51g/L when 4g malate/L was added during the rapid lipid accumulation stage in shake-flasks culture. Inducing effects of malate was further investigated through the analysis of three kinetic parameters, including specific cell growth rate (μ), specific glucose consumption rate (qGlu) and DHA formation rate (qDHA). DHA concentration was enhanced through a novel fed-batch strategy to a maximum value of 30.7g/L, giving a yield of 0.103g DHA/g glucose and a productivity of 284mgL-1h-1.ConclusionA novel malate feeding strategy was developed that enhanced DHA yield and productivity of Schizochytrium species which may offer a desirable method for industrial applications