Studies The Hydrolysis Conditions For Corn Stalks By Multi-enzymes

The low rate of enzyme hydrolysis in the process of cellulose degradation and high cost of the cellulose enzyme seriously restrict the biological transformation and use of lignocellulose. Research shows it is hard to reach the expected result in the process of enzyme solution only use one kind of hydrolysis enzyme. Therefore we need the common function by cellulose enzyme and other hydrolysis enzyme to achieve the better results.In this paper, firstly, we determined the optimal condition of enzyme hydrolysis corn stalks by single factor experiment, as followed:the usage of Cellulose enzyme is about60FPU/g (straw), pH4.8; Xylanase is90IU/g (straw), pH5.0; Pectinase is40IU/g (straw), pH3.8; Alpha amylase is60IU/g (straw), pH5.0, four kinds of enzyme respectively hydrolysis corn stalks48h under the condition of substrate concentration of20g/L,50℃,150r/min.And hydrolysis rate reached32.21%,30.07%,21.53%and16.10%in turn.Based on the result of the single factor experiment, we studied the proportion of Composite enzyme and the affixion order of multiple enzymese. The result showed that: under the synchronous hydrolysis condition of the liquid-solid ratio50:l,50℃,150r/min and48h, we added the optimal ratio of composite enzyme which were60FPU/g (straw) of cellulose enzyme,50IU/g (straw) of xylanase, pectinase20IU/g (straw), alpha amylase20IU/g (straw), whose hydrolysis rate was39.86%. The order of hydrolysis is cellulose enzyme, and Xylanase, then Pectinase finally Alpha amylase step by step, which can make hydrolysis rate reach43.75%.The research of solid fermentation using aspergillus to produce composite enzyme showed solid fermentation with aspergillus strain FIP-09-24can accumulate cellulose enzyme, xylanase and pectic enzymes.These were enzymes for the hydrolysis of corn straw.Aspergillus FIP-09-24producted composite enzyme for72h in28℃,then250ml buffer was used to extract enzyme for10h in4℃, which hydrolyzed corn straw.Under the hydrolysis condition of the liquid-solid ratio50:1,50℃,150r/min,48h, the hydrolysis rate can reach42.56%.