Background:
Malate 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.
Results:
DHA production increased by 47% and reached 5.51 g/L when 4 g malate/Lwas added during the rapid lipid
accumulation stage in shake-flasks culture. Inducing effects ofmalate was further investigated through the analysis
of three kinetic parameters, including specific cell growthrate (μ), specific glucose consumption rate (q
Glu) andDHA
formation rate (q
DHA). DHA concentration was enhanced through a novel fed-batch strategy to amaximumvalue of
30.7 g/L, giving a yield of 0.103 g DHA/g glucose and a productivity of 284 mg L
-1 h
-1.
Conclusion:
A novel malate feeding strategy was developed that enhanced DHA yield and productivity of
Schizochytrium species which may offer a desirable method for industrial applications.
