为提高能同时降解黄曲霉毒素B1和玉米赤霉烯酮的食品级重组乳酸克鲁维酵母GG799(pKLAC1-ZPF1)的培养生物量,对该菌进行了高密度培养条件优化。选择并试验了几种基础培养基的摇瓶培养效果,在此基础上采用单因素试验和响应面试验对该菌的培养基成分进行优化,采用单因素试验和正交试验对该菌的培养工艺参数进行优化,最后以5 L发酵罐扩大培养来验证优化结果。结果表明摇瓶优化的培养基成分为:葡萄糖20.41 g/L、蛋白胨30.46 g/L、酵母提取物24.73 g/L、KH2PO4 4.48 g/L、MgSO4 0.65 g/L,在此条件下获得生物量是对照的5.5倍;优化的培养参数为:培养温度26 ℃、转速220 r/min、初始pH 4.5,在此条件下获得生物量是对照的7.5倍。按照优化的培养基和培养参数进行发酵罐扩大培养,获得的生物量为(34.05±3.34) g/L,是摇瓶培养对照的29.6倍。研究结果为食品级重组乳酸克鲁维酵母工业化应用提供了重要理论依据和参考数据。
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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