title: Simultaneous degradation of cypermethrin and its metabolite, 3-phenoxybenzoic acid, by the cooperation of Bacillus licheniformis B-1 and sphingomonas sp. SC-1.
abstract: Cypermethrin (CY) and its metabolite, 3-phenoxybenzoic acid (3-PBA), generally coexist in agricultural soil and cause a toxic effect on the human body. In this study, CY and its metabolite 3-PBA were simultaneously degraded by the cooperation of Bacillus licheniformis B-1 and Sphingomonas sp. SC-1. The effects of the inoculation proportion and inoculation method of these two strains, cultivation time, and initial CY content on the degradation of CY and 3-PBA were investigated. Furthermore, the degradation of CY and 3-PBA in soil environment by using the cooperation of these two strains was also determined. When the inoculation proportion of the biomass of strain B-1/strain SC-1 was 3.3:6.7, strain B-1 was inoculated first, and strain SC-1 was inoculated after 24 h of cultivation, 75.60% CY (100 mg L(-1)) was degraded at 72 h and the 3-PBA content was 10.31 mg L(-1). Compared with those by using only strain B-1, the half-life of CY by using these two strains was shortened from 71.90 to 35.71 h, and the yield coefficient of 3-PBA was decreased from 0.8938 to 0.2651. As in the soil environment, the CY content by using these two strains within a period of 25 days declined from 22.71 to 5.33 mg kg(-1) and the 3-PBA content was 1.84 mg kg(-1). Compared with those by using only strain B-1, the half-life of CY by using these two strains was shortened from 19.86 to 11.34 days and the yield coefficient of 3-PBA was decreased from 0.5302 to 0.2056. This work could develop a promising approach for the simultaneous degradation of CY and its metabolite 3-PBA in agricultural soil.
authors: College of Light Industry and Food Engineering, Sichuan University , 610065 Chengdu, Sichuan, People's Republic of China.
authors: Fangfang
authors: F
authors: Liu
authors: Yuanlong
authors: Y
authors: Chi
authors: Shuang
authors: S
authors: Wu
authors: Dongying
authors: D
authors: Jia
authors: Kai
authors: K
authors: Yao
mesh_terms: D001407:Bacillus / Q000378:metabolism*; D001565:Benzoates / Q000737:chemistry / Q000378:metabolism*; D001673:Biodegradation, Environmental; D010575:Pesticides / Q000737:chemistry / Q000378:metabolism*; D011722:Pyrethrins / Q000737:chemistry / Q000378:metabolism*; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism; D020578:Sphingomonas / Q000378:metabolism*
chemical_list: D001565:Benzoates; D010575:Pesticides; D011722:Pyrethrins; D012989:Soil Pollutants; C017160:cypermethrin; C017618:3-phenoxybenzoic acid
keywords: 3-phenoxybenzoic acid; Bacillus licheniformis B-1; Sphingomonas sp. SC-1; cooperation; cypermethrin; simultaneous degradation