一株碱性木聚糖酶产生菌的筛选及发酵条件的优化  

Screening of a Strain Producing Alkaline Xylanase and Optimization of Fermentation Conditions

作　　者：易旭东[1] 潘虎[2] 田云[1] 刘博伦 林元山[1] 

机构地区：[1]湖南农业大学生物科学技术学院,长沙410128 [2]西藏自治区农牧科学院农业质量标准与检测研究所,拉萨850000

出　　处：《中国农学通报》2017年第17期12-18,共7页Chinese Agricultural Science Bulletin

基　　金：湖南省科技厅农村领域重点研发项目资助"水稻秸秆谷壳资源化利用与功能性低聚木糖的制备研究"(2016NK2114);湖南省研究生科研创新项目资助"碱性木聚糖酶的发酵制备及其相关基因的克隆"(CX2016B294);西藏自治区财政专项资金项目"拉萨河谷地区农田土壤有益微生物的研究与应用"

摘　　要：碱性木聚糖酶广泛用于造纸、纺织等领域。为筛选出高产碱性木聚糖酶的菌株,采用刚果红显色法,从山西省晋城市植物园土壤中筛选出一株碱性木聚糖酶产生菌株YH158,通过形态鉴定及16S r DNA序列分析,鉴定为甲基营养型芽孢杆菌(Bacillus methylotrophicus)。经发酵条件单因素优化及4因素3水平正交试验分析,确定了最佳的产酶培养基配方:麸皮5.0%、黄豆粕0.7%、硫酸锰0.1%。最佳培养条件:培养基初始p H 8.0,转速180 r/min,37℃发酵36 h,通过发酵条件的优化最终得到发酵液酶活为28.18 IU/m L。该菌产生的木聚糖酶具有较高的碱性适应性,水解产物富含2~5个木糖分子的低聚木糖,具有较高的工业应用前景。Alkaline xylanase is widely used in paper making and textile field. In order to screen strains producing high-yield alkaline xylanase, a strain YH 158 producing alkaline xylanase was isolated from the soil of the botanical garden in Jincheng City, Shanxi Province by congo red color reaction. Morphological test and 165 rDNA sequence analysis confirmed it was Bacillus methylotrophicus. The single factor optimization of fermentation conditions and the orthogonal test including four factors and three levels were used in this study. The optimal producing-alkaline-xylanase medium formulation was determined： wheat bran 5.0%, soybean extraction 0.7%, MnSO4 0.1%. The optimal culture condition： initial cultural pH 8.0, rotation speed 180 r/min, 37℃ fermentation 36 h. The enzyme activity was 28.18 IU/mL by fermentation optimization. Xylanase produced by this bacterium showed high alkaline adaptability, and its hydrolysis products were xylo- oligosaccharides rich in 2-5 xylose molecules, displaying higher industrialization prospect.

关 键 词：碱性木聚糖酶 低聚木糖 筛选 发酵优化 

分 类 号：Q939.9[生物学—微生物学]