Effect of the Kinetics of Cellulose Saccharification under Different Conditions

Abstract:

The cellulose is the main component of the strain to produce bio-fuel. The saccharification of cellulose to fermentable sugars is critical step to fermentation of stalk to synthesize biofuel. The effects of various reaction conditions on parameters of the kinetics of cellulose saccharifications reaction were studied using the sugar yield（Ytrs） as an index. The Impeded Michaelis model containing two parameters including the accessibility between enzyme and the substrate（K_obs，0） and the gradual loss of enzyme activity（K_i） could be fitted all experimental data well. The predicted maximum Ytrs（46%），K_obs，0（0.265 4 h-1），Ki（0.058 3 h-1）was obtained under the following conditions：pH of 4.41，temperature of 47 ℃，3% cellulase and 5% corn stover based on the model. The predicted results was in line with the experimental results. Temperature and pH mainly increase Ytrs by decreasing Ki，and the enzyme solubility and substrate concentration increases Ytrs mainly by increasing K_obs，0. Ytrs is significantly positively correlated with K_obs，0 and negatively correlated with K_i. This study lays the foundation for the saccharification of lignocellulose.