BioChem - DOS

Adaptive evolution of Schizochytrium sp. by continuous high oxygen stimulations to enhance docosahexaenoic acid synthesis

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Sun, X.M.; Ren, L.J.; Ji, X.J.; Chen, S.L.; Guo, D.S.; Huang, H.

Adaptive laboratory evolution (ALE) is an effective method in changing the strain characteristics. Here, ALE with high oxygen as a selection pressure was applied to improve the production capacity of Schizochytrium sp. Results showed that cell dry weight (CDW) of endpoint strain was 32.4% higher than that of starting strain. But slight lipid accumulation impairment was observed. These major performance changes were accompanied with enhanced isocitrate dehydrogenase enzyme activity and reduced ATP:citrate lyase enzyme activity. And a serious decrease of 62.6% in S<SUB>DHA 140rpm&rarr;170rpm</SUB> was observed in the endpoint strain. To further study the docosahexaenoic acid (DHA) production ability of evolved strain, fed-batch strategy was applied and 84.34g/L of cell dry weight and 26.40g/L of DHA yield were observed. In addition, endpoint strain produced greatly less squalene than starting strain. This work demonstrated that ALE may be a promising tool in modifying microalga strains.

2016

Elsevier Applied Science

publisher-specific-oa

0960-8524

211

pp.374-381

10.1016/j.biortech.2016.03.093

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART75353324

http://manuscript.elsevier.com/S0960852416303960/pdf/S0960852416303960.pdf

Schizochytrium sp; Docosahexaenoic acid; Adaptive evolution; Enzyme activity