产D-乳酸菊糖芽孢乳杆菌的诱变及发酵条件研究

Mutation Breeding and Optimization of Fermentation for Producing D-lactic Acid with Sporolactobacillus inulinus

以菊糖芽孢乳杆菌(Sporolactobacillus inulinus)为出发菌株,经紫外线、硫酸二乙酯的诱变处理,采用碳酸钙平板初筛及摇瓶复筛得到1株高产D-乳酸的正向突变株D11。通过单因素试验研究D11菌株发酵产D-乳酸的条件。结果表明,当发酵温度37℃,初始p H 6.5,转速160 r/min,接种量5%,装液量50m L/250 m L,发酵68 h,该菌株D-乳酸产量达到56.18 g/L,比出发菌种提高49.53%。

After the original strain Sporolactiobacillus inulinus was mutated by UV and DES and selected by CaCO3 plates,a D-lactic acid yield positive mutant D1l by fermenting in shake flask was obtained.Through the single factor experiment,the fermentation conditions of producing D-lactic acid was studied.The results showed that the D-lactic acid production reached 56.18g/L when the fermentation temperature was 37 ℃,initial pH was 6.5,the rotation speed was 160 rpm/min,inoculums was 5％（V/V）,liquid volume was 50 mL/250 mL,fermentation time 68 h.The D-lactic acid production reached 56.18 g/L and was enhanced by 49.53％ compared with original strain.