本试验旨在从竹鼠肠道中分离厌氧纤维素降解菌并鉴定。取中华竹鼠盲肠内容物稀释，采用含2种不同纤维素[微晶纤维素( MCC )和羧甲基纤维素钠( CMC-Na )]的培养基在厌氧条件下对纤维素降解菌进行初筛，后又经以纤维二糖为唯一碳源的培养基的多次复筛，选出的菌株进行经形态学和分子生物学的鉴定。结果表明：经过初筛和复筛，筛选出了2株厌氧纤维素降解菌。初筛培养基采用MCC和CMC-Na最终筛选出的2株纤维素降解菌的纤维素酶活力分别为6.599和5.268 U/mL。菌株经PCR鉴定、测序，用所得序列构建系统发育树，得出这2株菌与酪酸梭状芽孢杆菌( Clostridium butyricum)具有很高的同源性，达99%，二者均属于梭菌属( Clostridium)。本试验从竹鼠盲肠中成功筛选出2株纤维素降解菌，经鉴定确定属于梭菌属。%In order to isolate and identify anaerobic cellulolytic bacteria in intestine of rhizomyidae, cecum con-tent of Rnizomyssinehsis was collected and diluted. Culture mediums with different kinds of cellulose [ micro-crystalline cellulose ( MCC ) and sodium carboxymethyl cellulose ( CMC-Na ) , respectively ] were used for preliminary screening of cellulolytic bacteria under anaerobic condition, and then multiple screening using cul-ture medium with cellobiose as the only carbon source was carried out. The screened strains were identified by the methods of morphology and molecular biology. The results showed as follows: after preliminary screening and screening, two strains of anaerobic cellulolytic bacteria were isolated. After preliminary screening on cul-ture medium with MCC and CMC-Na, the cellulolytic enzyme activity of final screened strains was 6.599 and 5.268 U/mL, respectively. After PCR identification and sequencing, the sequence was used to construct phylo-genetic tree, and high homology was found between the two strains and Clostridium butyricum, which reached 99%. The two strains belonged to Clostridium. In conclusion, two strains of anaerobic cellulolytic bacteria are successfully screened from cecum in of rhizomyidae, and are belonged to Clostridium.
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