Optimal cultivation conditions for food-grade recombinant yeast that simultaneously degrades two mycotoxins
XIA Yu1*, WU Zifeng1, HU Xiuyu2, BAO Hongduo3, HE Rui1, QIU Yangyu1, CHENG Qianqian1, WANG Zhouping1
1(School of Food Science and Technology, Jiangnan University, Wuxi 214122, China) 2(China Biotech Fermentation Industry Association, Beijing 100833, China) 3(Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China)
Abstract: To improve the biomass of recombinant Kluyveromyces lactis GG799(pKLAC1-ZPF1), the optimal high-density cultivation conditions was conducted. The optimal conditions were verified in a 5 L fermentor. The results showed that the optimized culture composition was as follows: 20.41 g/L of glucose, 30.46 g/L of peptone, 24.73 g/L of yeast extract, 4.48 g/L of KH2PO4 and 0.65 g/L of MgSO4, and the biomass was 5.5 times of control. While the optimized cultivation parameters were as follows: 26℃, 220 r/min and the initial pH 4.5, and the biomass were 7.5 times of control. The biomass was (34.05±3.34) g/L in 5 L fermentor, which was 29.6 times of control. The results provided important theoretical basis and reference data for the future industrial production of K. lactis.
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