B.methylotrophicus SWU6菌株产纤维素酶发酵条件的优化  

The Optimization of Fermentation Conditions for SWU6-a Strain of the Cellulase-Producing BacteriumBacillus methylotrophicus

作　　者：吴晶晶[1] 徐伟芳[1] 王爱印[1] 周敏[1] 黄涛杨 谢洁[1] 

机构地区：[1]西南大学生物技术学院,重庆400716

出　　处：《蚕学通讯》2016年第2期1-6,共6页Newsletter of Sericultural Science

基　　金：西南大学本科生科技创新基金项目(No.1331002)

摘　　要：前期从自然界土壤中分离筛选到一株纤维素酶产生菌Bacillusmethylotrophicus SWU6菌株,为提高该菌株发酵产酶能力,本研究采用3,5-二硝基水杨酸显色法(DNS)对该菌株产酶所需碳源、氮源、温度、pH值、装瓶量、接种量等发酵条件进行优化,并比较优化前后等量发酵上清液中CMCase酶活大小。结果表明:SWU6菌株产纤维素酶的最适碳源为淀粉,最适氮源为牛肉膏,最适培养温度为50℃,培养基最适初始pH值为5.0,最适装瓶量为20%,最适接种量为2%;在最优发酵产酶条件下,SWU6菌株发酵上清液中的CMCase酶活达到454.69U/mL,明显高于优化前利用基础培养基发酵所产的CMCase酶活,且酶活提高约3倍。通过发酵条件优化后,SWU6菌株单位体积发酵液显示出了更强的纤维素酶活性。In a preliminary study,the strain Bacillus methylotrophicus SWU6 was screened and identified,which is a cellulase-producing bacterium.In order to improve its capacity of enzyme production,the present research optimized the amount of carbon and nitrogen,temperature,pH,bottling amount and inoculation amount by the 3,5-dinitrosalicylic acid colorimetric method（DNS）,and the CMCase activity in the supernatant before optimization and after optimization was compared.The result showed that optimum carbon source,nitrogen source,fermentation time,initial temperature and pH of the medium,media amount and inoculation amount for enzyme production of this strain were starch,beef extract,24 hours,50℃ and 5.0,20% and 2%,respectively.After optimization,the CMCase activity of the strain reached 454.69U/mL,which was three times higher than it was before optimization.And higher cellulase activity was exhibited in the same volume of fermentation broth of the strain SWU6 after fermentation optimization.

关 键 词：甲基营养型芽孢杆菌 纤维素酶 发酵条件 优化 

分 类 号：TQ925[轻工技术与工程—发酵工程]