Abstract

ORTIZ-HERNANDEZ, Ma. Laura  and  SANCHEZ-SALINAS, Enrique. Biodegradation of the organophosphate pesticide tetrachlorvinphos by bacteria isolated from agricultural soils in México. Rev. Int. Contam. Ambient [online]. 2010, vol.26, n.1, pp.27-38. ISSN 0188-4999.

A bacterial consortium which degrades tetrachlorvinphos (phosphoric acid, 2-chloro-1-(2,4,5-trichlorophenyl) ethenyl dimethyl ester) was isolated from agricultural soil. This consortium was composed of six pure strains which were characterized based on their morphological and biochemical characteristics. The strains were presumptively identified as Stenotrophomonas malthophilia, Proteus vulgaris, Vibrio metschinkouii, Serratia ficaria, Serratia spp. and Yersinia enterocolitica. The consortium and the six bacteria were assessed in order to discover their ability to degrade tetrachlorvinphos (TCV) in mineral medium and in rich medium. Growth curve experiments showed that the bacterial consortium was able to grow in mineral medium containing TCV as the only carbon source. However, only one pure strain was able to remove TCV in mineral medium, while all of them removed it in rich medium. Hydrolysis products were detected and identified by gas chromatography-mass spectrometry. These data indicate that the isolated strains can be used for waste biodegradation or bioremediation of TCV-contaminated soil or water.

Keywords : bacteria; biodegradation; pesticides; tetrachlorvinphos.