埃博霉素B高产菌株的选育及发酵工艺优化

Breeding of High Epothilone B Producing Strain and Optimization of the Fermentation Conditions

摘要:

以纤维堆囊菌(Sorangium cellulosum)SoF5-76为诱变出发菌株, 经紫外(UV)和亚硝基胍(NTG)复合诱变和筛选, 获得一株高产突变菌株SoF5-H23, 其发酵产埃博霉素B的量可达79.83 mg/L, 比出发菌株提高了1.27倍。通过Plackett-Burman实验和响应面分析法对纤维堆囊菌产埃博霉素B的发酵工艺进行优化。得到最佳发酵工艺为：马铃薯淀粉4.8 g/L, 葡萄糖0.5 g/L, 脱脂奶粉2.3 g/L, 豆饼粉2 g/L, 七水硫酸镁2 g/L, 无水氯化钙2 g/L, EDTA-Fe3+ 2 mL/L, 微量元素(TE)0.5 mL/L, 吸附树脂2%, 培养基初始pH 7.4, 装液量50 mL, 接种体积分数8%, 温度30 ℃。在此最优条件下埃博霉素B产量为 108.67 mg/L, 比优化前提高了36.13%, 此产量是国内外报道的埃博霉素最高产量。

Abstract:

A high epothilone B producing mutant SoF5-H23 was screened from Sorangium cellulosum SoF5-76 by combination treatment with UV and NTG. This mutant has good stability of producing epothilone B and production was 79.83 mg/L, which was 1.27 times higher than that of original strain. Plackett-Burman design and the response surface methodology(RSM) were applied to optimize medium for fermentation and conditions. The obtained optimal fermentation conditions were potato starch 4.8 g/L, skim milk powder 2.3 g/L, glucose 0.5 g/L, soybean powder 2 g/L, magnesium sulfate 2 g/L, chlorine calcium 2 g/L, EDTA-Fe3+ 2 mL/L, trace elements 0.5 mL/L, absorbent resin 2%, pH 7.4, liquid volume 50 mL/250 mL, inoculum size 8%, temperature 30 ℃. Under this optimal conditions, epothilone B production reached up to 108.67 mg/L which is the highest yield of epothilone B on home and overseas and was 36.13% higher than preliminary conditions.