蒸汽爆破维压时间对胡枝子成分、结晶度及酶解糖化的影响  

Influence of steaming time during steam-explosion on the chemical composition,crystallinity and enzymatic hydrolysis of Lespedeza bicolor stalks

作　　者：王堃[1] 王芳[1] 蒋建新[1] 孙润仓[1] 刘圣英[1] 马雅琦[1] 宋先亮[1] 

机构地区：[1]北京林业大学材料科学与技术学院

出　　处：《北京林业大学学报》2009年第5期121-125,共5页Journal of Beijing Forestry University

基　　金：教育部新世纪优秀人才支持计划(NCET-07-0082);"948"国家林业局引进项目(2004-4-40)

摘　　要：为研究爆破维压时间对胡枝子原料化学成分、结晶度的影响,采用蒸汽爆破预处理方法,以胡枝子为原料,在爆破压力为2.25MPa,爆破维压时间为2、3、4、5、6、10min的条件下进行试验。结果表明:蒸汽爆破处理后纤维素、木素含量变化不大,而半纤维素含量显著降低;蒸汽爆破处理后的物料结晶度比未处理的木质纤维素原料提高了60.67%。以胡枝子为酶解糖化原料,考察了温度、时间、用酶量、底物浓度4个影响因素,得到了最佳的条件为:温度46℃、时间60h、用酶量80U、底物浓度5%。在此条件下,对比了原料与不同蒸汽爆破维压时间处理后胡枝子物料的酶解糖化率。结果表明:蒸汽爆破预处理可使糖化率提高约2.8倍,达到84%,极大地提高了纤维素酶的可及度,是一种有效的预处理方法。The objective of this study is to evaluate the effects of steaming time on the shrub （ Lespedeza bicolor ） biomass treated by steam explosion. The chemical composition, crystallinity and enzymatic hydrolysis of the lignocellulosic residues were studied. The stalks were firstly steamed at 2.25 MPa for 2,3,4,5,6,10 min, respectively, and then exploded. The results showed that no significant differences in the content of cellulose and lignin were observed during the various steam explosion pretreatments, while the content of hemicelluloses was found to be decreased obviously. It was found that the crystallinity of cellulose in the residues was increased by 60.67 %, probably due to the removal of amorphous district. The optimum enzymatic hydrolysis condition was found to be 46 ℃, 60 hrs, 80 U cellulase dosage and 5 % substrate concentration, taking the raw material as substrate. It was also found that the steam explosion pretreatment effectively enhanced the enzymatic hydrolysis to 84 %, which was about 2.8 times higher than the un-pretreated raw material by greatly improving the accessibility of cellulose. Therefore, it can be concluded that the steam explosion is an effective pretreatment process.

关 键 词：胡枝子 蒸汽爆破 爆破时间 化学成分 结晶度 酶解糖化 

分 类 号：TQ92[轻工技术与工程—发酵工程]