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As flame retardants, organophosphate is recognized as a global environmental contaminant because of its wide application. This contaminant is hardly degradable by hydrolysis in the environment due to its special physicochemical properties. Therefore, it is of urgent needs to study the microbial degradation of organophosphate. Through continuous enrichment, we isolated one bacterial consortium, named YC-BJ1, from leachate of waste treatment plant in Beijing. The bacterial consortium YC-BJ1 could efficiently degrade 99.8% of triphenyl phosphate (TPhP) and 91.9% of tricresyl phosphate (TCrP) with the concentration of 100 mg/L within 4 days. Besides aryl phosphates, it could degrade chloro-phosphates, tris(1,3-dichloroisopropyl) phosphate (TDCPP) and tris(2-chloroethyl) phosphate (TCEP) by 16.5% and 22.0% respectively. The degradation of the consortium on TPhP was optimized through a broad range of temperature (15-40 ℃), pH (5.0-12.0) and salinity (0%-4%). 16S rRNA gene-based metagenomic analysis revealed that Hyphomicrobium (38.80%), Chryseobacterium (17.57%) and Sphingopyxis (17.46%) were the dominant genera of the consortium YC-BJ1. Compared with the reported organophosphorus flame retardants (OPFRs) degrading bacteria and microflora, the mixed microflora YC-BJ1 exhibited great advantages in degradation efficiency and environmental adaptability, demonstrating its wide application potential. The enrichment and isolation of highly efficient degrading flora can provide abundant microbial resources for the degradation of OPFRs and the bioremediation towards OPFRs-contaminated environments, and also lay a solid foundation for the exploration of its degradation mechanism.

Objective: An antagonistic bacterial strain YB-3 against Rhizoctonia solani was isolated from soils., Methods: Antagonistic strains were isolated by a reporter strain method. YB-3 was identified based on morphology observation, physiological and biochemical characterizations, Biolog, G + C content and 16S rDNA sequence analysis. The antagonistic spectrum and the properties of the inhibitor produced by Bacillus amyloliquefaciens YB-3 against plant pathogenic fungi and bacteria were investigated by means of plate two-way cultivation and disc diffusion method., Results: The strain YB-3 against Rhizoctonia solani was identified as Bacillus amyloliquefaciens. The antagonistic results showed that it had distinctively inhibitive effects on 14 pathogenic fungi and 7 bacteria. In addition, it also had inhibitive effects on strains from genus Bacillus to which YB-3 belongs. Antagonistic properties of B. amyloliquefaciens YB-3 was thermostable, acid resistant, and protease sensitive., Conclusion: Bacillus amyloliquefaciens YB-3 was isolated and characterized which had distinctively inhibitive effects on Rhizoctonia solani and had broad-spectrum, highly efficient to plant pathogens.

Objective: To isolate and characterize bacteria to degrade cypermethrin (CP)., Methods: We used enrichment culture to isolate and characterize bacterial strains based on the observation of morphological and biochemical characters and analysis of 16S rRNA gene sequences. We determined the concentration of CP, metabolite, densities of strain cells and cell surface hydrophobicity (CSH) in pure culture liquid., Results: We isolated a bacterium able to effectively degrade CP from polluted wastes of pesticide plant and assigned it as strain L12. Phylogenetic analysis based on 16S rRNA gene showed the similarity of 99% between strain L12 and Bacillus cereus. In pure culture with CP as the sole carbon and energy source, 85.6% of CP at initial concentration of 50 mg /L was degraded in 5 days. Thin layer chromatography (TLC) analysis of the culture extracts revealed presence of a metabolite (R(f)0.13), and HPLC analysis confirmed the retention time of the metabolite (2.26 min) corresponded with 3-phenoxybenzoic acid (3-PBA) standard. The method of microorganism adhering to hydrocarbon (MATH) was used to analyze strain L12 of the highest CSH of 68.91%., Conclusion: The results showed that strain L12 belonged to Bacillus cereus, which showed CSH and capacity to degrade CP to 3-PBA.