Screening of stalk cellulose-degrading microorganisms and construction of a microbial community with high capacity | 纤维素降解菌的筛选与高效混合菌群的构建

Chinese. 从土壤中筛选纤维素降解菌，对其进行组合培养获得可高效降解纤维素的混合菌群，为微生物混合培养降解纤维素提供理论基础。采用刚果红纤维素琼脂平板培养基从土样中初步筛选纤维素降解菌，再以内切酶（CMC）、纤维素全酶（FPA）、外切酶（C1）和β-葡萄糖苷酶（β-Gase）4种酶活性为指标进行复筛，对复筛获得的高效菌株进行组合培养，筛选高效组合菌群。对复筛后的菌株通过菌落和菌体形态进行初步鉴定。筛选获得了y3、yi-71、ye-9、er-72和se-93等5株活性较高的纤维素降解菌，对其进行组合培养，得到1个较好组合ye-9/er-72/se-93，其CMC、FPA、C1和β-Gase 4种酶活性分别为3.18，1.67，1.08和1.12 U/mL，均比单菌株有一定程度提高。初步鉴定ye-9、er-72、se-93均为放线菌。组合菌群对纤维素的降解效果优于单一菌株。

English. The cellulose-degrading bacteria were expected to be obtained from the soil, and get them mixed and cultured, then the microbial community degradating cellulose efficiently can be obtained to provide a theorotical basis on mixed fermentation between microorganisms. Cellulose congo-red culture medium was used to screen soil samples, and then CMC, FPA, C1 and β-Gase were used to re-screen, by which the strains with high capacity were obtained. The stains were miyed cultured, and a microbial community with high capacity was screened. The strains were judged by the characteristics of the colony form and individual form. Five strains that could decompose cellulose better were obtained from soil samples. Then they were cultured by mixed fermentation. The combination of ye-9/er-72/se-93 enhanced cellulase activities containing CMC, FPA, C1 and β-Gase to some degree, and the activity of CMC, FPA, C1 and β-Gase was 3.18, 1.67, 1.08 and 1.12 U/mL. The strains of ye-9, er-72 and se-93 were judged as actinomycetes preliminarily. The study found that the enzyme activity of the microbial community was higher than that from the fermentation of single bacteria.