1株类球红细菌及其降解敌敌畏的特性

Degradation of Dichlorvos by Rhodobacter sphaeroides

类球红细菌具有广泛的代谢方式,它能够发酵生产5-氨基乙酰丙酸、辅酶Q10、类胡萝卜素、氢气等,已经成为一种非常有工业化开发潜力的微生物.从土壤中分离、筛选了1株类球红细菌（编号为EBL0706）,分析了它的培养和遗传特性,测定了水溶液的pH、温度、敌敌畏浓度、类球红细菌浓度对其降解敌敌畏速率的影响,结果表明,该菌株在水溶液中能够快速矿化敌敌畏,在pH 6.9-7.5、温度20-50℃条件下,在5×10^8CFU/mL的类球红细菌稀释液中,400 mg/L的敌敌畏在12 h内降解率达到98%以上.该菌株发酵液的稀释液喷洒到幼苗期的白菜叶片上,能够显著加快残留敌敌畏降解速度,显示出其在无公害农产品生产中的应用潜力.

Rhodobacter sphaeroides possesses an extensive range of energy acquiring mechanisms including photosynthesis, lithotrophy, aerobic and anaerobic respiration. It can produce 5-aminolevulinic acid, CoQ10, carotenoids, hydrogen, etc. by fermentation. A Rhodobacter sphaeroides strain was isolated, designated as EBL0706, from soil. The degradation of dichlorvos （DDVP） by the Rhodobacter sphaeroides was investigated. 98% of DDVP could be degraded in water solution in 12 h when 5 × 10^8 CFU/mL Rhodobacter sphaeroides was added to 400 mg/L DDVP solution under pH 6.9-7.5 and 20-50℃. This strain could also degrade the DDVP residues on Chinese cabbage leaves effectively.