In order to improve the treatment effect of wastewater from pesticide enterprise, it is necessary to study the salt-tolerant characteristics and fermentation conditions of the degrading bacterium. A chlorpyrifos-degrading bacterium Bacillus cereus HY-1 was isolated in laboratory from pesticide wastewater. The optimal fermentation medium and fermentation conditions of HY-1 were selected by rnsingle factor and orthogonal test， and the amount of enzyme produced by HY-1 was estimated based on rnthe specific activity of the enzyme. The experimental results were analyzed by the SPSS system. The rnoptimal composition of the culture medium included glucose 6.0 g/L, tryptone 2.2 g/L, KH2PO4 2.0 g/L,rnK2HPO4 0.2 g/L, MgSO4'7H2O 0.1 g/L, NaCl 0.1 g/L, trace elements solution 2 mL/L. The optimal rnfermentation conditions of HY-1 were that incubation time of the seed culture was 16 h, fermentation rntime was 18 h. inoculum amount was 1％ (V/V), initial pH 7.0. The specific activity of the degrading rnenzyme was not affected while the sodium chloride concentration of the fermentation medium inrncreased from 0 g/L to 30 g/L. To the best of our knowledge, this is the most extremely salt-tolerant rnbacterium reported that could degrade chlorpyrifos.%为了明确生化处理和微生物降解的关系,通过增加耐盐菌的比例可以提高农药废水生化处理效果.从农药厂废水中分离到1株耐盐性毒死蜱降解菌--蜡状芽孢杆菌(Bacillus cereus HY-1).以从该菌中提取到的降解酶比活力为指标,进行产酶培养基和发酵条件的优化研究.通过单一因素试验和正交试验,对细菌HY-1的产酸培养基和发酵条件进行了优化.运用SPSS软件进行结果分析,所获优化培养基配方为:葡萄糖6.0 g/L,胰蛋白胨2.2 g/L,K2HPO4 2.0 g/L,KH2PO4 0.2 g/L,MgSO4·7H2O 0.1 g/L,NaCl 0.1 g/L和微量元素溶液2 mL/L.得到菌株发酵培养的最佳优化条件为:种子液培养时间为16 h,发酵培养时间为18 h,接种量为1%(V/V),发酵培养基初始pH值为7.0.氯化钠浓度为0-30g/L时降解酶比活力不受影响,这是已报道的耐盐性最强的一株毒死蜱降解菌.
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