The performance of D⁃lactic acid fermentation using hydrolysate of wheat bran by Sporolactobacillus inulinus YBS1⁃5 was investigated. Considering the differences of hydrolysis efficiency by different protease of wheat bran, we setected acid protease and optimized the hydrolysis condition.The nitrogen concentration of hydrolysate was 4�6 g/L and the hydrolysis efficiency was 85�8%. Using cellulase to hydrolyze wheat bran that was pretreated by diluted acid. By the optimal fed⁃batch, the reducing sugar concentration in the hydrolysate was 141�2 g/L,glucose concentration was 138�1 g/L and xylose concentration was 1�4 g/L. We used the hydrolysate as carbon source and nitrogen source to produce D⁃lactic acid.After 96 h fermentation,the concentration of D⁃lactic acid was 99�5 g/L,the rate of production was 1�04 g/( L·h) and the conversion ratio was 89�1%.%考察菊糖芽孢乳杆菌YBS15利用麸皮的水解液发酵生产D 乳酸的性能。首先研究了不同蛋白酶对麸皮中蛋白组分的水解效率，优选酸性蛋白酶并对其进行水解工艺的优化，最终其水解液中的含氮量为4�6 g／L，水解效率为85�8％。对酸性蛋白酶的水解液残渣进行稀酸预处理后，利用纤维素酶对其进行酶解。通过批次补料酶解，水解液中的还原糖质量浓度达141�2 g／L，其中葡萄糖质量浓度为138�1 g／L、木糖质量浓度为1�4 g／L。利用麸皮的蛋白酶水解液和纤维素酶水解液替代葡萄糖和酵母粉发酵制备D 乳酸。在96 h内， D 乳酸产量达99�5 g／L，生产速率达1�04 g／（ L·h），转化率89�1％。
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