Screening on the Cellulose-decomposing Microorganisms and Optimization of Fermentation Conditions

The study is aimed to screen cellulose decomposing microorganisms with good decomposition effect.With straw that contained microorganisms,rotten leaves and soil in maize field as materials,after the enrichment culture and primary screening,the microorganism was isolated according to the diameter of hydrolyzed circle/cultured days.The crude enzyme liquid was prepared for the determination of CMC Case activity and FPA.The optimized object was decided through changing conditions for the enzyme reaction.Then the single factor optimization was done.The results showed that 4 strains were isolated from the sample with one being better than others.The CMC Case activity and FPA of H-3 was 0.5401.It is concluded that strains H-3 has the strongest ability to decompose cellulose;the optimum conditions include :the cultural temperature set at 30℃,pH at 4.5,absence of urea,the concentration of GLC and cellulose being 0.3% and 0.5% respectively.