乳酸乳球菌乳酸亚种T0625菌株产Nisin最佳培养条件的研究

STUDYING ON THE OPTIMAL NISIN PRODUCTION CONDITION OF LACTOCOCCUS LACTIS SUBSP. LACTIS T0625

对从大白菜叶片上分离得到的一株乳酸乳球菌乳酸亚种T0625产乳酸链球菌素(Nisin)的适宜培养条件进行了研究。采用单因素分析法首先确定了T0625菌株在改良的M17G培养基中产Nisin的最适碳源、氮源、金属离子的种类,即:碳源为葡萄糖;氮源为蛋白胨、酵母膏和牛肉膏组成的混合氮源;金属离子为Mg2+。并确定了各成分的最适浓度。之后确定了装液量、接种量、起始pH和培养温度的最适指标。最终通过正交试验的方法,确定T0625产Nisin的最佳营养条件:葡萄糖2%、蛋白胨4%、酵母膏2%、牛肉膏1%、MgSO4.7H2O0.003 mol/L、VC0.05%。T0625产Nisin的最佳发酵条件:装液量250 mL(250 mL三角瓶)、接种量7%、起始pH 6.5、35℃下发酵培养12 h。

In this paper, a Nisin-Produced Lactococcua lactis subsp. Lactis T0625 isolated from the leaf of Chinese cabbage was studied. First, by single factor experiments, optimal carbon source ,nitrogen source and metalion in improved M17G culture medium used for Nisin-producing were determined. Namely, carbon source was glucose; nitrogen source was mixed nitrogen source; metal ion was Mg^2＋, and optimal concentration of each component was ascertained. Then, optimal poured solution volume, inoculated number, initial pH and culturing temperature were determined. Finally, by orthogonal experiments, the optimum culture medium and optimal fermentation conditions of producing Nisin were obtained as follow： 2 % glucose, 4 % peptone, 2 % yeast extract, 1% beef extract, 0.003 mol/L MgSO4·7H2O, 0.05 % Vitamin C; poured solution volume 250 mL （in 250mL triangle bottle）, inoculated number 7 %, initial pH 6.5, culturing temperature 35 ℃ for 12 h.