蚕沙纤维素降解菌HB-2菌株的分离、鉴定及酶活性分析  

Isolation and identification of cellulose-degrading bacterium HB-2 and characteristics of its enzyme activity

作　　者：岑贞陆[1] 胡钧铭[2] 韦仕岩[1] 何铁光[2] 李婷婷[2] 曾泉[1] 

机构地区：[1]广西农业科学院微生物研究所,南宁530007 [2]广西农业科学院农业资源与环境研究所,南宁530007

出　　处：《南方农业学报》2016年第12期2065-2071,共7页Journal of Southern Agriculture

基　　金：广西科学研究与技术开发计划项目(桂科重14121002-4-6);生态广西建设引导资金项目(桂财政函[2015]87);广西农业科学院基本科研业务费专项项目(桂农科2016ym32);来宾市科技攻关项目(来科攻143608)

摘　　要：【目的】筛选蚕沙纤维素降解菌株,为蚕沙无害化快速腐熟处理提供优质菌种。【方法】以蚕沙为材料,利用CMC-Na培养基分离蚕沙纤维素降解菌,通过形态学、生化特征和16S rDNA序列测定方法等对分离获得的纤维素降解菌进行分类学鉴定,并研究碳源、氮源、pH、培养时间和培养温度对分离菌株产酶活力的影响。【结果】从蚕沙中筛选出1株高温型细菌,命名为HB-2菌株。根据菌体大小、鞭毛着生位置及数量、16S rDNA核酸序列分析,并结合生理生化特性,HB-2菌株鉴定为短小芽孢杆菌(Bacilluspumilus)。HB-2菌株最佳产酶条件为复合碳源(蚕沙+微晶纤维素+米糠+麸皮)、复合氮源(蛋白胨+酵母膏),产纤维素酶最适反应pH 6.5,最适温度35℃。【结论】HB-2菌株CMCase活性较敏感且产酶量大,具有制成菌剂应用于蚕沙无害化快速腐熟的潜力。【Objective】 Cellulose-degrading bacteria were isolated from silkworm,in order to provide high-quality strain for harmless quick composting of silkworm excrement.【Method】 Using CMC-Na culture medium,cellulose-degrading bacteria were isolated from silkworm excrement.Then obtained cellulose-degrading bacteria were identified based on its morphology,biochemical characters,16 S rDNA sequence etc.And effects of carbon source,nitrogen source,pH,culture time and culture temperature on cellulase activity of isolated strain were studied.【Result】Results showed that,a strain of high-temperature resistant bacterium was screened out,which was named HB-2 strain.According to its size,flagella position and number,16 S rDNA sequence and physio-biochemical characteristics,HB-2 strain was identified as Bacillus pumilus.Enzyme-producing conditions of HB-2 strain were as follows：composite carbon sources including silkworm excrement＋microcrystalline cellulose＋rice bran＋wheat bran,composite nitrogen sources including peptone＋yeast extract,optimum pH for cellulose producing being 6.5,optimum temperature for cellulose producing being 35℃.【Conclusion】HB-2strain has sensitive CMCase activity and produces a large amount of cellulase,so which can be made into bactericide,then applied to harmless quick composting of silkworm excrement.

关 键 词：蚕沙 纤维素降解菌 短小芽孢杆菌 鉴定 酶活性 

分 类 号：Q939.124[生物学—微生物学]