纤维二糖发酵生产丙酮丁醇

分别考察C.acetobutylicum 810705、810706以不同浓度的麸皮和玉米粉添加物作为营养元素,纤维二糖直接进行丙酮丁醇(ABE)发酵的结果,发现2株菌对于玉米粉和麸皮的浓度变化趋势一致,C.acetobutylicum 810706转化率较高。纤维二糖ABE发酵工艺条件表明:玉米粉添加量为总糖含量的30%、底物糖质量浓度60 g/L,pH 6.5、温度35℃时,C.acetobutylicum 810706转化率达到37.38%,总溶剂质量浓度22.43 g/L,比葡萄糖、木糖ABE发酵转化率高。模拟纤维素酶水解产物配制混合糖培养基,其溶剂转化率较单独的葡萄糖、木糖发酵的转化率高,为34.95%。对比纤维素酶水解条件,C.acetobutylicum 810706具有优良的纤维素酶水解同步糖化ABE发酵能力。

Acetone-butanol fermatative production using cellobiose

Fermantative production of acetone-butanol by C. acetobutylicum 810705 and C. acetobutylicum 810706 was studied from cellobiose with different additive amounts of bran and corn starch. The same var- iation tendency of solvent concentration and substrate conversion was testified, and substrate conversion of C. acetobutylicum 810706 was a little higher. Corn starch was proved to be better nutritional supplements than bran, and the optimum additive ratio was 30% of total sugar. Based on the optimization of culture conditions, C. acetobutylicum 810706 achieved a 37.38% substrate conversion and 22.43 g/L solvent concerntration, and it was better than fermantative production of acetone-butanol from glucose and xylose while cultured at 35 ℃ with 60 g/L sugar concentration of substrate and initial pH 6.5. Mixed sugar sub- strate prepared by imitating the concentration of cellulose enzymatic hydrolysis was fermented. 34.95% of substrate conversion was obtained, and it was higher than any single sugar. Results showed that C. acetobutylicum 810706 had excellent potential of cellulose saccharified by enzymatic hydrolysis and ac- etone-butanol fermentation simultaneously.