解淀粉芽孢杆菌对水中丁草胺的降解及影响

用解淀粉芽孢杆菌(Bacillus amyloliquefaciens)作为试验菌种,对除草剂丁草胺(N-丁氧甲基氯-2′-氯-2′,6′-二乙基乙酰替苯胺)在水介质中的微生物降解进行了研究.筛选了解淀粉芽孢杆菌降解丁草胺的最佳试验条件,研究了不同初始pH和添加外源腐殖酸对丁草胺微生物降解的影响.用高效液相色谱法(HPLC)检测了丁草胺残留量和降解产物,用红外光谱法(FTIR)分析测定了反应前后腐殖酸的变化情况.结果表明:解淀粉芽孢杆菌对丁草胺具有明显的降解效果,丁草胺初始质量浓度越高,其降解速率和降解效率也越高,碱性条件下丁草胺的降解率明显比酸性条件下高;腐殖酸的加入不仅能吸附丁草胺还能促进细菌对丁草胺的微生物降解,并能影响丁草胺的微生物降解产物. 

Biodegradation of Herbicide Butachlor in Water Media Using Bacillus amyloliquefaciens

Biodegradation of herbicide butachlor (N-butoxymethyl-2′-chloro-2′,6′-diethy lacetanilide) in aqueous media using Bacillus amyloliquefaciens was investigated. The conditions for butachlor biodegradation were optimized. Effects of different initial pH values and addition of humic acids (HAs) on biodegradation of butachlor were studied. The variation of butachlor residues and biodegradation products was analyzed by high performance liquid chromatography (HPLC). The change of HAs under different reaction conditions was determined by fourier transform infra red (FTIR) spectroscopy. It was demonstrated that Bacillus amyloliquefaciens can degrade butachlor efficiently. Degradation rate increased with the initial concentrations of the tested herbicide and media pH. The addition of exogenous HAs can enhance the adsorption of butachlor, accelerate the biodegradation process of butachlor, and affect the biodegradation products in the meantime.