研究通过NREL法分析麦糟成分,确定了纤维素酶与半纤维素酶的添加量.单因素实验明确了碱过氧化氢法(AHP)预处理NaOH 的适宜添加量,比较了未预处理和AHP 预处理的麦糟酶解效果.结果显示:最适NaOH 添加量为0.08 g/g底物,AHP预处理能有效提高麦糟酶解糖得率;在20%底物浓度下,AHP预处理组葡萄糖与木糖转化率分别提高了 29.8%,13.3%.在 AHP 预处理基础上对25%底物浓度麦糟进行水洗,结果表明:水洗能有效提高麦糟酶解糖的转化率,较未水洗组,葡萄糖与木糖转化率分别提升8.23%和7.98%.在水洗基础上利用Design Expert进行Mixture实验设计,设计纤维素酶、半纤维素酶与果胶酶联合酶解麦糟的加酶比例.模型显示,最佳加酶比例为纤维素酶∶半纤维素酶为0.63∶0.37.在该加酶比例下,葡萄糖转化率达到89.73%,较优化前提升7.1%,木糖转化率也相对提升7.5%.%The major components of brewers'spent grain (BSG)are analyzed.Single factor experiment is conducted to optimize the amount of NaOH added during AHP pretreatment,the enzymatic hydrolysis of BSG with/without AHP pretreatment is also investigated.The results show that the proper addition of NaOH is 0.08 g/g,and AHP pretreatment could improve the sugar conversion rate of BSG efficiently compared with the untreated group.Under the biomass-loading of 20%,the glucose and xylose conversion rates of AHP pretreated group are improved 29.8% and 13.3% respectively.The optimal time of enzymaitic hydrolysis is 24 h.The water wash of 25%biomass loading BSG based on the AHP pretreatment is performed,the results show that water wash could improve the sugar conversion rate, the glucose and xylose conversion rates are improved 8.23% and 7.98% respectively comparing with the control group.The cocktail of ctec 2 ,htec 2 and pectinase is studied by using mixture design with the software Design Expert.The model shows that the optimum addition is ctec2∶htec is 0.63∶0.37 on the protein amount basis.The glucose conversion rate is 89.73% during enzymatic hydrolysis of water-washed BSG under such condition,which is increased by 7.1%,the xylose conversion rate has also been improved 7.5%.
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