产抗氧化胞外多糖海洋细菌Bacillus subtilis OST23a的诱变育种

摘要

利用产生抗氧化活性胞外多糖的海洋细菌Bacillus subtilis OST23a为出发菌株进行高产菌株的诱变选育。采用紫外、硫酸二乙酯复合诱变处理后筛选得到一株高产胞外多糖的优良突变菌株UD292，发酵产胞外多糖水平达到43．92mg／L，较出发菌株提高了6．26倍，且多糖的抗氧化活性没有显著变化。对突变菌株进行连续传代实验结果表明突变菌株遗传性状稳定。%Bacillus subtilis OST23a, a marine bacterium, was mutagenized with both UV light and DES treatment to obtain a high-yield antioxidant exopolysaccharide （EPS）-producing strain named as UD292. The EPS yield of the mutant strain was 43.92 mg/L, which increased 6.26-fold as compared with the original strain. The EPS obtained from both strains showed no obvious difference in their antioxidant activity. The mutant strain remained stable in successive passages.