Screening of the cellulase-producing fungi and its enzyme-producing conditions in compost.

Cattle manure and its compost samples were selected to obtain an effective cellulose-decomposing microorganism,a fungi strain of F12 producing high level of cellulase was screened out by primary culture on plates of cellulose-Congo red medium and secondary fermentation in liquid medium.The strain was identified as Penicillium based on the morphologic taxonomy.The effects of carbon source,nitrogen source,initial pH of medium,inoculation quantity,culture temperature and time on cellulase activity produced by the strain were studied.The results indicated that the optimum conditions of producing cellulase were as follows: carbon source was bran and microcrystalline cellulose complex,nitrogen source was ammonium sulfate,initial pH value was 5-6,inoculation quantity was about 5%,culture temperature was 30-35℃,culture time was 120 h.Under these conditions,the activities of CMCase and FPA were 47.5 IU/mL and 11.1 IU/mL respectively.