Cultivation of Candida utilis WSH02-08 for Production of Glutathione by Amino Acids Addition Strategy
WU Xiao-yu DU Guo-cheng CHEN Jian
Key Laboratory of Industrial Biotechnology, Ministry of Education Lab of Environmental Biotechnology, School of biotechnology Southern Yangtze University Key Lab. Industrial Biotechnol., Ministry of Education, Jiangnan University
Abstract： The effects of amino acids addition on glutathione production of C. utilis WSH 02-08 were investigated. The results showed that two-step amino acids addition could greatly increase GSH production level. The optimal conditions for two-step amino acids addition strategy were obtained as follows: 4 mmol/L L-cysteine was added after 10 h cultivation, and a mixture of three amino acids (L-glutamic acid, L-cysteine and glycine) was added at 16 h. The optimum concentrations of those three amino acids (8 mmol/L L-glutamic acid, 8 mmol/L L-cysteine and 12 mmol/L glycine) were obtained by orthogonal experiments, GSH concentration and intracellular GSH content reached to 290.1 mg/L and 3.22%. Combining the amino acids addition strategy and high-cell-density cultivation by glucose feeding, 20 mmol/L L-cysteine was added at 36 h, and then the three amino acids (40 mmol/L L-glutamic acid, 40 mmol/L L-cysteine and 60 mmol/L glycine) were added at 45 h, GSH concentration and intracellular GSH content reached to 1725.3 mg/L and 3.29%, which were higher (111.4% and 100.6%) than those of high-cell-density cultivation (816 mg/L and 1.64%).