Inhibitory effect of vanillin on cellulase activity in hydrolysis of cellulosic biomass
作者单位:State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of Sciences University of Chinese Academy of Sciences
会议名称:《中国生物工程学会2014年学术年会暨全国生物技术大会》
会议日期:2014年
学科分类:080702[工学-热能工程] 08[工学] 0807[工学-动力工程及工程热物理] 09[农学] 0903[农学-农业资源与环境]
关 键 词:vanillin cellulase inhibition kinetics HCH-1 model inhibitory group
摘 要:Researches on bioconversion of lignocellulosic materials for biofuel production have attracted great attention all over the world due to both the abundance of cheap and renewable cellulosic biomass and the consumption of nonrenewable fossil fuels. However, the current bioconversion process is still not commercially viable and cost-competitive in great part due to the recalcitrance of cellulosic biomass. It has been believed that the presence of lignin in lignocelluloses contributes greatly to the recalcitrance. On one hand, with tight association with cellulose and hemicellulose, lignin acts as a barrier to prevent the access of cellulolytic enzymes to the substrate;on the other hand, lignin unproductively absorbs cellulase, decreasing the amount of available cellulase for hydrolyzing. In order to reduce the recalcitrance of lignocellulosic biomass, biomass-disrupting pretreatment is required prior to enzymatic hydrolysis. Most of the prevalent pretreatments, however, are performed under severe conditions, resulting in formation of phenolic compounds from degradation of lignin. These phenolic compounds identified in lignocellulosic hydrolyzates include simple phenolics(vanillin, ferulic acid, syringaldehyde and conifer alcohol, etc.) and oligomeric phenolics(ellagia acid, epicatechin and tannic acid, etc.). The amount and type of phenolic compounds depend on the biomass source, pretreatment methods and conditions. The inhibition of lignin-derived phenols on fermentative strains has been widely investigated, whereas few reports are available on their inhibition on cellulose hydrolysis. Kim et al.(2013) investigated the effect of soluble inhibitors on cellulase and found that phenolic compounds and xylo-oligosaccharides were the most important causes leading to the decrease in cellulase activity. Ximenes et al.(2011;2010) confirmed that vanillin, syringaldehyde, trans-cinnamic acid and hydroxybenzoic acid inhibited cellulose hydrolysis in wet cake. What’s more, their