高温纤维素降解微生物的筛选、鉴定及其酶活力测定  

Screening,identification and enzyme activity determination of high temperature cellulose degrading microorganism

作　　者：李建树 孙丽坤 韩向敏[1] 张明盩 LI Jian-shu;SUN Li-kun;HAN Xiang-min;ZHANG Ming-zhou(College of Animal Science and Technology,Gansu Agricultural University,Lanzhou 730070,China;Lanzhou Livestock and Poultry Breeding and Promotion Center,Lanzhou 730000,China)

机构地区：[1]甘肃农业大学动物科学技术学院,甘肃兰州730070 [2]兰州市畜禽育种推广中心,甘肃兰州730000

出　　处：《甘肃农业大学学报》2020年第3期29-37,共9页Journal of Gansu Agricultural University

基　　金：甘肃省科技厅青年基金项目(18JR3RA181);兰州市科技计划项目(2019-1-85)。

摘　　要：【目的】筛选高温高效纤维素降解微生物,为畜禽粪便和农作物秸秆堆肥菌剂的研制奠定基础.【方法】在50℃培养条件下,对牛粪自然堆肥样品中的纤维素降解微生物进行富集、分离、纯化培养.又经刚果红纤维素培养基法、滤纸条崩解试验、纤维素酶活测定法进行纤维素降解活性的筛选.再提取菌株DNA,分别扩增16S rDNA或ITS片段进行鉴定.【结果】最终筛选得到具有良好纤维素降解性能的细菌(X-1)和真菌(Z-3)各1株.Z-3菌株在5 d内能将滤纸条完全崩解,X-1菌株则为7 d.X-1菌株在7 d内羧甲基纤维素酶(CMCase)、滤纸酶(FPA)和微晶纤维素酶(C1)最高活力分别为0.47、0.08、0.12 IU/mL;Z-3菌株则为0.32、0.14、0.07 IU/mL.分子生物学鉴定结果表明,X-1为伯氏短杆菌(Brevibacillus borstelensis),Z-3为枝孢菌属(Cladosporium).【结论】得到了2株高温降解微生物,50℃降解纤维素能力较强(培养基),可进一步用于堆肥菌剂的开发.【Objective】Aiming at screening high temperature resistant microbes with high efficiency for cellulose degradation in order to provide the composting agents for livestock manure and crop straw.【Method】The cellulose-degrading microorganisms were isolated,enriched and purified under 50℃condition from collected natural compost samples of cattle manure.The cellulose degrading activity was screened by Congo red cellulose medium method,filter paper strip disintegration test,and cellulose activity assay.Then the DNA of candidate strains were extracted and identified with 16S rDNA and ITS region.【Result】A bacterium strain(X-1)and a fungi strain(Z-3)with cellulose degradation ability were screened out.Strain Z-3 was able to disintegrate the filter paper completely within 5 days,while strain X-1 was 7 days.The maximum activity of carboxymethyl cellulose(CMCase),filter paper enzyme(FPA)and microcrystalline cellulose(C1)of strain X-1 within 7 days were 0.47,0.08 and 0.12 IU/mL,respectively.The maximum enzyme activity of strain Z-3 within 7 days were 0.32,0.14 and 0.07 IU/mL.The molecular biology identification results showed that X-1 was Brevibacillus borstelensis and Z-3 was from Cladosporium.【Conclusion】The obtained two strains have strong ability to degrade cellulose on the medium at 50℃,which can be used for the development of composting agents.

关 键 词：纤维素降解菌 筛选 酶活力 鉴定 

分 类 号：X172[环境科学与工程—环境科学]