一株纤维素降解菌的筛选、鉴定及产酶条件优化  

Screening and Identification of a Cellulose-degrading Bacterium in the Aerobic Composting of Biogas Residues and Optimization of Enzyme Production Conditions

作　　者：钟斌 陶文玲 倪思毅 安雪姣 夏祥 张庆华[1] ZHONG Bin;TAO Wenling;NI Siyi;AN Xuejiao;XIA Xiang;ZHANG Qinghua(College of Bioscience and Biotechnology,Jiangxi Agricultural University,Nanchang 330045,China)

机构地区：[1]江西农业大学生物科学与工程学院,江西南昌330045

出　　处：《江西农业大学学报》2021年第5期1167-1177,共11页Acta Agriculturae Universitatis Jiangxiensis

基　　金：江西省重点研发专项(20192BBF60055);江西省教育厅重点科技项目(GJJ180174);江西省杰出青年人才资助计划项目(20171BCB23044);江西省研究生创新专项资金(YC2019-S186);国家级大学生创新创业训练项目(202010410034)。

摘　　要：【目的】为筛选出高效降解厌氧消化残余物的纤维素降解菌,实现农业废弃物的高值化利用。【方法】本研究使用纤维素-刚果红透明圈法和酶活测定法从沼渣堆肥中分离出一株高效纤维素降解菌,结合形态学观察并通过16S rRNA测序,对该菌株进行鉴定。然后对该菌株的培养时间、培养温度、初始pH和接种量等培养条件进行单因素优化,并在此基础上以羧甲基纤维素酶(CMCase)和滤纸酶(FPase)活性为优化目标对该菌株的产酶条件进行响应面优化。【结果】分离出的一株纤维素降解菌F3为产碱杆菌(Alcaligenes faecalis strain),响应面优化结果表明,当培养温度、pH、培养时间和接种量分别取35℃、7.0、3 d和2%时,CMCase和FPase活性达到最高,分别为2.63 U/mL和2.23 U/mL,比未经优化前分别提高了29.56%和32.74%。【结论】该菌株在常温条件下具有较高的降解木质纤维素的能力,具有开发成沼渣高效好氧堆肥菌剂的潜质,为沼渣的高值化生物转化提供了优质菌种资源,为沼气工程的可持续发展奠定一定的基础。[Objective]To screen out cellulose-degrading bacteria that efficiently degrade anaerobic digestion residues,and realize high-value utilization of agricultural wastes[.Method]In this study,a high-efficiency cellulose-degrading bacterium was isolated from the biogas residue compost using the cellulose-Congo red transparent circle method and the enzyme activity determination method,combined with morphological observation and 16S rRNA sequencing to identify the strain.Then the culture conditions for the strain,such as culture time,culture temperature,initial pH,and inoculum amount were optimized by single factor,and on this basis,carboxymethyl cellulase(CMCase)and filter paper enzyme(FPase)activities were used as the optimization target and the enzyme production conditions for this strain were optimized by response surface.[Result]The results showed that the isolated cellulose-degrading bacterium F3 was an Alcaligenes faecalis strain.The response surface optimization results showed that when the culture temperature,pH,culture time,and inoculum size were 35℃,7.0,3 d and at 2%,the activities of CMCase and FPase reached the highest,2.63 U/mL and 2.23 U/mL,respectively,which were 29.56% and 32.74% higher than those before optimization.[Conclusion]This strain has a high ability to degrade lignocellulose under normal temperature conditions and has the potential to develop into an efficient aerobic composting of biogas residues.It provides high-quality strain resources for high-value biological conversion of biogas residues and contributes to biogas engineering,laying a certain foundation for sustainable development of biogas engineering.

关 键 词：纤维素降解菌 菌种鉴定 产酶优化 响应面优化 

分 类 号：Q93-331[生物学—微生物学]