响应曲面优化秸秆稀酸水解工艺用于发酵产壳聚糖

摘要

To optimize the usage of hemicellulose hydrolysate( HH) for chitosan production,the effect of different pretreatment condition of hemicellulose on chitosan production by Rhizopus oryzae was studied. The results showed that high temperature and/or long reaction time had significant effect on the concentration of xylose and inhibitors(formic acid,acetic acid,furfural),resulting influence in chitosan production. Through the quadratic model analyzed by response surface methodology(RSM),the optimal pretreatment condition of hemicellulose for chitosan production was 99�5 ℃,H2 SO4 13�6 g/L,1�91 h. Under this condition,chitosan production could reach 0�82 g/L,which was a little higher than the predict value of model ( 0�79 g/L) ,and account for 15%⁃18%of the biomass. The present study would provide a potential route for lignocellulose utilization and chitosan production.%为实现利用秸秆水解产生的五碳糖发酵产壳聚糖，以米根霉为研究对象，研究水解温度、水解时间、酸浓度等不同预处理方式获得的半纤维素水解液对米根霉发酵产壳聚糖的影响。结果表明：水解温度、水解时间对水解液中木糖含量以及甲酸、乙酸、糠醛等抑制剂浓度具有显著影响，并进一步影响后续发酵产壳聚糖的生成量。利用响应曲面对稀酸水解预处理条件进行优化，获得最佳工艺条件：H2 SO413�6 g／L，99�5℃，水解时间1�91 h，在此条件下预测壳聚糖发酵产量为0�79 g／L，实验验证产量为0�82 g／L，占菌体生物量的15％～18％。研究结果为秸秆资源的高效利用及发酵生产壳聚糖提供新思路。