微生物降解除草剂氯磺隆、甲磺隆和丁草胺的毒性效应(Ames试验)

TOXIC EFFECTS OF HERBICIDES CHLOROSULFURON, METSULFURON AND BUTACHLOR AFTER DEGRADATED BY MICROORGANISMS (AMES TEST)

为了解氯磺隆、甲磺隆和丁草胺经微生物降解后,对环境有无潜在危害,我们采土样接种于以上述除草剂(初始浓度分别为125,200,400ppm)为唯一碳源、能源和氮源的培养基中,振荡培养。以灭菌土样作对照。定时取样,经微孔滤膜抽滤后,以Ames试验平板掺入法检测其致突变性。结果表明,氯磺隆和甲磺隆经微生物降解后,与降解前一样,无致突变作用;微生物降解丁草胺的过程中可生成诱变剂,而这类代谢产物可继续被微生物降解,其致突变性随之消失。

In order to investigate the potential harmful effects of herbicides chlorosulfuron, metsulfuron and Butachlor to environment after degrada-ted by microorganisms, soil samples were inoculated and cultivated oscil-latingly in nutrient broth containing chlorosulfuron, metsulfuron or butachlor (the initial concentrations were 125 ppm, 200ppm and 400ppm, respectively) as the only sources of carbo, energy and nitrogen, with controls in which sterilized soil samples were inoculated.The borth samples were collected at regular intervals. Plate incorporation assay of Ames Test was used to detect their mutagenicity after f ilteration.The results indicate that chlorosulfuron and metsulfuron are not mu-tagenic before and after they are degradated by microorganism.The muta-gens are formed during in the degradation of butachlor by microorganisms-, these metabolites can be continually degradated and become non-mutagenic.