微生物转化污泥制备苏云金杆菌生物杀虫剂  

Bioconversion of Sewage Sludge to Biopesticide by Bacillus thuringiensis

作　　者：常明[1] 周顺桂[1] 卢娜[1] 倪晋仁[1] 

机构地区：[1]北京大学环境工程系教育部水沙科学重点实验室,北京100871

出　　处：《环境科学》2006年第7期1450-1454,共5页Environmental Science

基　　金：广东省自然科学基金项目(5006694);广东省科技攻关项目(2005B10401008)

摘　　要：以城市污水处理厂的污泥为原料,探索了微生物转化污泥制备苏云金杆菌生物杀虫剂的可行性,并与常规培养基的发酵进程进行了对比.主要考察了苏云金杆菌的代谢特征、菌体形态与杀虫晶体蛋白产量.研究表明:无需任何预处理工序,污泥所含营养成分即可基本满足苏云金杆菌生长需求,且增殖较快,24h即可达活菌数与活芽孢数的最大值:9.48×108CFU.mL-1和8.51×108CFU.mL-1,比常规培养基提前12h,数量分别提高17%和21%;36h SEM表征显示,污泥中晶体与芽孢大部分游离,且晶体较大,呈规则的菱形,而常规培养基中苏云金杆菌的代谢进程相对滞后,且晶体较小;至发酵终点污泥中杀虫晶体蛋白含量为2.80 mg.mL-1,亦略高于常规培养基.采用污泥发酵制备苏云金杆菌生物杀虫剂大大降低了生产成本,且发酵性能优良,为污泥处置开辟了崭新途径.Feasibility of bioconversion of sewage sludge to biopesticide by Bacillus thuringiensis was studied using sewage sludge as a raw material. The fermentation was also compared with conventional medium. Results showed that without any pretreatment, the nutrients contained in sewage sludge were almost sufficient for Bacillus thuringiensis growth, even with a rapid multiplicational rate. Higher viable cells and viable spores values were obtained earlier at 24 h, with 9.48 × 10^8 CFU· mL^-1 and 8.51 × 10^8 CFU· mL^-1 respectively, which was 12 hours earlier and nearly 20 percent higher than conventional medium. SEM of 36 h samples gave a clear phenomenon that the metabolizability in sludge was much faster with spores and crystals spreading around. The crystals in sludge seemed rather bigger and more regular. Also a better crystal protein yield of 2.80 mg· mL^- 1 was observed in sludge medium compared to conventional medium at the end of fermentation. Sludge fermentation for Bacillus thuringiensis reduces the producing cost, and gives better fermentation capabilities. It＇s expected to be a new method for sludge disposal.

关 键 词：污泥处置 苏云金芽孢杆菌 生物杀虫剂 

分 类 号：X703[环境科学与工程—环境工程]