解淀粉芽孢杆菌DMBA-K4高产胞外多糖的发酵条件优化及其抗氧化活性研究  

Optimization of fermentation conditions and anti-oxidation of exopolysaccharide produced by Bacillus amyloliquefaciens DMBA-K4

作　　者：邝嘉华 黄燕燕[1] 胡金双 余佳佳 周钦育 赵珊 刘冬梅[1] KUANG Jiahua;HUANG Yanyan;HU Jinshuang;YU Jiajia;ZHOU Qinyu;ZHAO Shan;LIU Dongmei(School of Food Science and Engineering,South China University of Technology,Guangzhou 510640,China)

机构地区：[1]华南理工大学食品科学与工程学院,广东广州510640

出　　处：《食品与发酵工业》2020年第22期28-35,共8页Food and Fermentation Industries

基　　金：国家自然科学基金(31771908);广州市科技计划项目(201903010015)。

摘　　要：从云南普洱茶中分离出1株产胞外多糖(exopolysaccharide,EPS)的菌株,经16S r DNA鉴定,确定该菌株为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)DMBA-K4;利用单因素和响应面法优化其胞外多糖的产量,并对其体外抗氧化活性进行研究。经优化后,DMBA-K4产胞外多糖的最佳发酵条件是:4 g/L蔗糖、5 g/L胰蛋白胨、10 g/L酵母提取粉、5 g/L NaCl、培养时间18 h,pH 7.6,接种量3.10%;在此条件下,其胞外多糖产量为171.31 mg/L,较原始条件提高155.7%。抗氧化实验结果表明,DMBA-K4所产的胞外多糖具有较强的抗氧化活性。当EPS质量浓度为5 mg/mL时,其1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率达78.60%,对·OH的清除率为75.47%。该研究可为微生物胞外多糖的工业生产提供理论支持,丰富新型微生物多糖的应用前景。An exopolysaccharides(EPS)producing strain was isolated from Yunnan Puer tea.This strain was defined as Bacillus amyloliquefaciens DMBA-K4 by 16S rDNA.Single factor trials and response surface tests were performed to optimize its EPS yield,and its in vitro antioxidant activity was also investigated.The optimal fermentation conditions were as follow:the culture medium consisted of 4 g/L sucrose,5 g/L tryptone,10 g/L yeast,5 g/L NaCl,pH 7.6,inoculator amount of 3.10%and fermented for 18 h.Under these conditions,the maximal yields of EPS increased by 155.7%and reached 171.31mg/L.In vitro antioxidant results showed that EPS had strong antioxidant activity.When the concentration of EPS was 5 mg/mL,the scavenging rate of DPPH free radical and·OH was 78.60%and 75.47%,respectively.The research provide theoretical support to EPS industrialization and widen the utilization prospect of novel bio-polysaccharide.

关 键 词：解淀粉芽孢杆菌 胞外多糖 发酵条件 响应面优化 抗氧化 

分 类 号：TS201.3[轻工技术与工程—食品科学]