海洋细菌Sphingomonas sp.Q2产琼胶酶发酵条件优化、酶学性质及降解产物研究  

Optimization of Fermentation Conditions,Enzymatic Properties and Degradation Products of Agarase Produced by Marine Bacterium Sphingomonas sp.Q2

作　　者：钱洗谦 乔乐克 张洪锋 江晓路[4] 王鹏[1] 张京良 QIAN Xiqian;QIAO Leke;ZHANG Hongfeng;JIANG Xiaolu;WANG Peng;ZHANG Jingliang(Ocean University of China,College of Food Science and Engineering,Qingdao 266003,China;Qingdao Institute of Marine Biomedicine,Qingdao 266100,China;Qingdao Hailaimei Company,Qingdao 266400,China;Ocean University of China,College of Medicine,Qingdao 266003,China)

机构地区：[1]中国海洋大学食品科学与工程学院,山东青岛266003 [2]青岛海洋生物医药研究院,山东青岛266100 [3]青岛海莱美生物科技有限公司,山东青岛266400 [4]中国海洋大学医药学院,山东青岛266003

出　　处：《食品工业科技》2023年第18期139-146,共8页Science and Technology of Food Industry

基　　金：基于酶酵耦合的紫菜提取技术研究与开发(2020N3016);蔬菜病害高效绿色药肥产品的开发和产业化(22-3-7-xdny-2-nsh)。

摘　　要：本研究旨在对从江蓠中筛选获得的Sphingomonas sp.Q2菌株产琼胶酶能力条件进行优化并对其酶学性质及降解产物进行研究。通过响应面法对发酵条件进行优化,采用硫酸铵沉淀、离子交换层析和凝胶层析等方法对发酵所得酶液进行纯化并对纯化后的酶液进行酶学性质研究。发酵优化结果表明该菌株产琼胶酶的最佳培养基组成为:琼脂4.42 g/L、磷酸氢二钾1.30 g/L、氯化钠10.51 g/L。优化后的酶活力为1085.71 U/mL,较优化前提高了1.58倍。纯化后的琼胶酶比活为112048.82 U/mg,纯化倍数为7倍,回收率为48.04%。酶学性质结果表明该酶最适反应温度为40℃,最适pH为6.5,且在最适温度下保存8 h,酶活仍保持在90%以上。MS和^(13)C-NMR结果表明,该琼胶酶的降解产物主要为新琼四糖。该琼胶酶具有良好的热稳定性及较高的酶活力,为琼胶寡糖的开发制备提供了基础。This study was aimed at optimization of the fermentation conditions for agarase production by Sphingomonas sp.Q2 which was isolated from Gracilaria and characterization of its enzymatic properties and degradation products.The optimum fermentation conditions were determined by response surface analysis.The agarase was purified by(NH4)2SO4 precipitation and column separation and its enzymatic properties was investigated.The results indicated that the optimal culture medium components for agarase production were agar 4.42 g/L,K2HPO41.30 g/L,NaCl 10.51 g/L.The highest enzyme activity of 1085.71 U/mL was obtained,which was 1.58 times compared with the initial activity.The crude enzyme was purified 7 times with 112048.82 U/mg of enzyme activity.The recovery rate of agarase was 48.04%.The enzyme had optimal temperature and pH of 40℃and 6.5,respectively.The enzyme activity remained above 90%when stored at the optimum temperature for 8 h.The capital hydrolysates were identified as neoagarotetraose by MS and^(13)C-NMR.The agarase showed a good thermal stability and high stability,which laid the foundation for the development and application of functional oligosaccharides agar.

关 键 词：SPHINGOMONAS sp. Q2 琼胶酶 发酵优化 分离纯化 酶学性质 降解产物 

分 类 号：TS201.3[轻工技术与工程—食品科学]