Characterization Of Miscanthus Lignocellulose Substrats That Affect Trichoderma Reesei Producing Cellulase

Miscanthus,a dedicated energy crop with high biomass production,is attracting an attention for bioenergy purpose.Cellulase enzyme is the 3^rd largest industrial enzymes and accounts for approximately 20%of the total enzyme markets over the world,because it can be applied in many indurtries including paper,textile,biofuel,food and animal feed.In particular,the cellulase demans will be enhanced by biofuel production in near future.To improve activity of fungal cellulases and minimize the cost of cellulase production,many efforts have been made by strain modification and medium optimization,but much remains unknown about lignocellulose substrate effects.Hence,it remains to find out how the cell composition and structure affect Trichoderma reesei to produce cellulase enzymes.In this study,thirty Miscanthus accessions with distinct cell wall composition were used as substrates for incubation with Trichoderma reesei.We initiately investigated effects of cell wall composition and wall polymer features on celluase production by Trichoderma reesei.The wall polymer features included lignocellulose crystallinity（Cr I）,degree of polymerization（DP）of crystalline cellulose,momosaccharide composition of hemicelluloses and three momolignol（S,G,H）proportions of lignin in Miscanthus accessions.As a result,the cell wall compositions of Miscanthus accessions could lead to varied cellulase activities ranging from 6.31 to22.8(10^-2FPU/ml).Further correlation analyses indicated that cellulose Cr I and DP,starch content and S/G ratio negatively affect cellulase activities at p<0.05 and p<0.01 levels（n=30）.By comparison,the hemicelluloses contents（Arabinose and Xlyose）exhibited a positive correlation with cellulase axctivity at p<0.05 and p<0.01 levels（n=30）.In addition,the cellulase activities were consistently confirmed by digesting commercial cellulose samples.