A High-yield Cellulase Strains Screening And Optimization Of Its Fermentation Conditions

Cellulose is the most abundant in nature, the most extensive natural renewable resources. Along with the petroleum, natural gas and other resources are scarce, alcohol production by cellulose and carbohydrate is increasingly becoming a hot research. Cellulose by cellulase enzymes into the role of glucose, and then biological fermentation to produce alcohol foreground is very wide, not only can reduce CO2emission is used for fuel, also can reduce the gasoline and other non-renewable energy dependence.Congo red medium transparent circle method, from the bamboo forest borers, cow dung and other materials were screened for nearly70cellulolytic ability of the strains. Through the anaerobic culture, selected from10strains of facultative anaerobic bacteria. Finally through the filter paper strip collapse method for determining56enzyme capacity of the strongest. Through physiological and biochemical analysis and molecular identification, decision No.56strain of Bacillus for methanol (Bacillus methylotrophicus), named LJ-56.To be selected out of the LJ-56strains optimization of enzyme production condition and orthogonal test. Research results show that, the optimal fermentation conditions were:the most suitable carbon source for CMC-Na; the optimum carbon source added:0.4%-0.5%; the optimum nitrogen source:(NH4)2SO4; the optimum nitrogen source added:0.4%; the optimum pH:9.0; optimum fermentation time:4d; optimal inoculation quantity:in2ring, the most suitable temperature:35℃. The optimum CMCase activity reached37.5U/mL, FPA enzyme activity to0.44U/mL, respectively, higher than the original strain74.42%and22.22%.