复合诱变选育高产α-环糊精葡萄糖基转移酶的菌株及产酶条件优化  

Strain breeding for high-yieldingα-cyclodextrin glucosyltransferase and optimization of the enzyme formation conditions

作　　者：陶大炜 张小丹 宁喜斌[1,2,3,4] 孙梦洁 TAO Dawei;ZHANG Xiaodan;NING Xibin;SUN Mengjie(College of Food Science and Technology,Shanghai Ocean University,Shanghai 201306,China;Shanghai Engineering Research Center of Aquatic-Product Processing&Preservation,Shanghai 201306,China;Laboratory of Quality and Safety Risk Assessment for Aquatic Products on Storage and Preservation(Shanghai),Ministry of Agriculture,Shanghai 201306,China;National R&D Branch Center for Freshwater Aquatic Products Processing Technology(Shanghai),Shanghai 201306,China)

机构地区：[1]上海海洋大学食品学院,上海201306 [2]上海水产品加工及贮藏工程技术研究中心,上海201306 [3]农业部水产品贮藏保鲜质量安全风险评估试验室(上海),上海201306 [4]国家淡水水产品加工技术研发分中心(上海),上海201306

出　　处：《食品与发酵工业》2021年第19期63-70,共8页Food and Fermentation Industries

摘　　要：对出发菌株Paenibacillus macerans TLLY7进行紫外-微波复合诱变,以获得高产α-环糊精葡萄糖基转移酶的菌株,并用响应面法优化复合诱变菌株的发酵条件来提高酶活力。确定了紫外、微波诱变的最佳条件:20 W紫外灯照射70 s,微波低火档辐照60 s。筛选出复合诱变菌株UM2-6,经过8次连续传代培养,验证其遗传性能较稳定,菌株酶活力可达3.09 U/mL,是出发菌株酶活力(1.35 U/mL)的2.29倍。在单因素试验的基础上,通过Plackett-Burman试验筛选出影响发酵的3个显著性因素:培养温度、初始pH、接种量,设计Box-Behnken中心组合试验确定菌株最优发酵条件。结果表明,最佳发酵培养基成分为可溶性淀粉10 g/L、酵母浸粉10 g/L、NaCl_(2)g/L、CaCl_(2)0.2 g/L、K_(2)HPO 4·3H_(2)O 1 g/L,最佳发酵条件为培养温度37.1℃、初始pH 6.9、接种量4%,此时突变菌株UM2-6产α-环糊精葡萄糖基转移酶的酶活力为4.19 U/mL,为优化之前酶活力(3.09 U/mL)的1.36倍。该研究为进一步工业化开发利用性状稳定且高产α-环糊精葡萄糖基转移酶的菌株提供了借鉴。Paenibacillus macerans TLLY7 was mutated by irradiation with 20 W UV lamp for 70 s and microwave irradiation at low power for 60 s,and a high-productionα-cyclodextrin glucosyltransferase(α-CGTase)strain UM2-6 was obtained with stable genetic performance.The results showed that the optimal fermentation culture medium were 10 g/L of soluble starch,10 g/L of yeast powder,2 g/L of NaCl,0.2 g/L of CaCl_(2)and 1 g/L of K_(2)HPO4·3H_(2)O.The optimal fermentation conditions were 37.1℃,initial pH 6.9 and inoculum volume 4%.Strain UM2-6 produced 4.19 U/mLα-CGTase,which was 1.36 times than that of before optimization(3.09 U/mL).This study provides a reference for further industrial development using strains with stable and high production ofα-CGTase.

关 键 词：复合诱变 紫外诱变 微波诱变 Α-环糊精葡萄糖基转移酶 发酵条件优化 

分 类 号：TQ925[轻工技术与工程—发酵工程]