高效杀蚊苏云金芽孢杆菌BRC-LLP29的发酵优化  

Fermentation Optimization of Novel Mosquitocidal Bacillus Thuringiensis Strain BRC-LLP29

作　　者：陈宇熹[1] 叶舒婷[1] 蔡美凤[1] 张灵玲[1] 关雄[1] 

机构地区：[1]福建农林大学生物农药与化学生物学教育部重点实验室,福建福州350002

出　　处：《生物数学学报》2012年第1期175-185,共11页Journal of Biomathematics

基　　金：国家863项目(2011AA10A203);卫生部科学研究基金(WKJ2008-2-44);国家自然科学基金(31071745);教育部博士点基金(20093515110010);科技部农业科技成果转化资金(2010GB2C400212);福建省科技厅产学研重点项目(2011N5003);福建省高校服务海西建设重点项目(0b08b005)

摘　　要：苏云金芽孢杆菌BRC-LLP29为新型高效杀蚊菌株,应用快速有效的数学统计方法对其杀蚊毒力的发酵培养进行优化.通过单因素筛选确定最佳碳源为葡萄糖、麦芽糖、可溶性淀粉,氮源为typetone、大豆蛋白胨、干酪素;最佳金属离子为Mg^(2+)、Al^(3+).采用二水平Placlkett-Burman设计对影响毒力的8因素进行显著性筛选,获得培养基成分中3个重要影响因子:葡萄糖、干酪素和Al_2(SO_4)_3;运用爬坡路径法对这3种因子进行试验,获得3种重要因子的最适浓度范围;通过响应面分析法得到3个重要因子的交互作用和最佳条件,确定BRC-LLP29菌株最佳毒力水平的发酵培养基为:葡萄糖19.8g/L、干酪素28.4g/L、Al_2(SO_4)_31.2g/L、MgSO_4 2g/L、K_2HPO_4 3g/L、CaCO_3 0.5g/L,优化后毒力水平达到致死率61.11%,与响应面数学模型的预测值只有5.91%的误差.发酵条件优化结果表明:发酵温度为31°,发酵初始pH为7.0,摇瓶装量为40mL/250mL三角瓶,每瓶的接种量为3.5%,发酵72h,对致倦库蚊最终致死率达到最高为83.33%.BRC-LLP29 is a novel and mosquitocidal Bacillus thuringiensis strain. Statistical methods were used to optimize the fermentation conditions. According to single factorial experiments, glucose, maltose and soluble starch were the most suitable carbon sources, while typetone , casein and soy peptone were the best nitrogen sources. Meanwhile, Mg2＋ and A13＋ were both the best metal ions. It also showed in Plaekett-Burman design that glucose, soy peptone and A12 （SO4）awere the key three factors on toxicity in culture medium. Tile path of steepest ascent experiment was employed to approach the optimal region of the medium concentration. The optimal combined concentration and mutual effect of the three factors were optimized by response surface methodology（RSM）. It showed that the best media composition were glucose 19.8 g/L, casein 28.4g/L, A12（SO4）a1.2g/L, MgSO42g/L, K2HPO43g/L and CaCO3 0.5g/L, respectively. Based on this condition, the corrected mortality to Culez quinquefasciatus was 61.11%, which was only 5.91% error from the forecast by RSM. In additon, analysis for culture conditions indicated that 31℃ was the most suitable fermentation temperature. When BRC-LLP29 was cultured for 72h with 250mL shake flasks, 7.0 of the initial pH and 3.5% of the density, the mortality of C. quinq^tefasciatus could reach to 83.33%

关 键 词：苏云金芽孢杆菌 发酵优化 致倦库蚊 校正死亡率 

分 类 号：Q815[生物学—生物工程]