低温纤维素降解细菌Duganella sp.的分离及降解能力解析  

Isolation of a Duganella sp.of degrading cellulose bacterium at low temperatures and analysis of its degradation capacity

作　　者：陈昭 王敬红 邓常宇 邹世杰 范寒雪 魏丹 孙宇峰[4] 王伟东[1,2] CHEN Zhao;WANG Jinghong;DENG Changyu;ZOU Shijie;FAN Hanxue;WEI Dan;SUN Yufeng;WANG Weidong(College of Life Science and Biotechnology,Heilongjiang Bayi Agricultural University,Daqing 163319,Heilongjiang,China;College of Life Science,Northeast Forestry University,Harbin 150400,Heilongjiang,China;Institute of Plant Nutrition,Resources and Environment,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China;Daqing Branch of Heilongjiang Academy of Sciences,Daqing 163319,Heilongjiang,China)

机构地区：[1]黑龙江八一农垦大学生命科学技术学院,黑龙江大庆163319 [2]东北林业大学生命科学学院,黑龙江哈尔滨150400 [3]北京市农林科学院植物营养与资源环境研究所,北京100097 [4]黑龙江省科学院大庆分院,黑龙江大庆163319

出　　处：《微生物学通报》2024年第6期2158-2169,共12页Microbiology China

基　　金：国家自然科学基金区域创新发展联合基金(U22A20444);国家重点研发计划(2023YFD1500501);中央高校基本科研业务费专项基金(2572023CT08)。

摘　　要：【背景】低温是寒区秸秆还田后微生物降解的主要限制因素之一。【目的】获得低温纤维素降解细菌以提高寒区秸秆资源化利用率低的问题。【方法】取冬季土壤样品进行富集,以羧甲基纤维素钠(sodium carboxymethyl cellulose, CMC-Na)为唯一碳源,采用稀释涂布等方法分离纯培养菌株,通过单因素试验及正交试验对菌株产酶条件进行优化。【结果】获得一株15℃条件下降解纤维素的细菌,初步归类为杜擀氏菌属(Duganella)。其最佳产酶条件为:培养温度15℃,初始pH值7.0,装液量50/100 mL,接种量12.5%,此时的CMC酶活最高为398.2 U/mL,比优化前提高了40.45%。菌株在最佳培养条件下对滤纸、水稻秸秆和玉米秸秆的降解率分别为19.24%、9.48%和7.30%。【结论】本研究为寒区秸秆降解微生物资源提供了新的菌种资源,同时为后续低温纤维素降解菌株的研究提供了数据参考。[Background]Low temperatures are one of the main factors limiting microbial degradation of straw returned to the field in cold regions.[Objective] To obtain the bacterial strains capable of degrading cellulose at low temperatures to improve the straw reutilization in cold regions.[Methods]The soil samples were collected in winter for strain enrichment with sodium carboxymethyl cellulose(CMC-Na)as the sole carbon source.The pure culture of the strain was obtained by the dilution-plate coating method,and the enzyme production conditions of the strain were optimized by single factor and orthogonal tests.[Results]A cellulose-degrading strain was obtained at 15℃ and identified as Duganella sp.The optimal enzyme production conditions of the strain were incubation with the liquid loading volume of 50/100 mL and inoculum volume of 12.5%at 15℃ and initial pH 7.0,under which the highest CMC enzyme activity was 398.2 U/mL,40.45%higher than that before optimization.The degradation rates of filter paper,rice straw,and maize straw by the strain were 19.24%,9.48%,and 7.30%,respectively,under optimal culture conditions.[Conclusion]This study provides new strain resources for straw degrading microbial resources in cold regions,as well as data reference for subsequent research on low temperature cellulose-degrading strains.

关 键 词：低温 纤维素降解 产酶条件优化 

分 类 号：X172[环境科学与工程—环境科学]