title: Metabolism and biochemical pathway of n-butyl benzyl phthalate by Pseudomonas fluorescens B-1 isolated from a mangrove sediment.
abstract: n-Butyl benzyl phthalate (BBP) is an endocrine-disrupting chemical. Biodegradation of BBP was investigated using the bacterium Pseudomonas fluorescens B-1 isolated from mangrove sediment of Mai Po Nature Reserve of Hong Kong. The microorganism was capable of utilizing BBP as the sole source of carbon and energy while BBP was degraded in 6 days under aerobic batch culture conditions. The optimum pH, temperature, and salinity for BBP degradation by P. fluorescens B-1 was found to be 7.0, 37 degrees C, and 15 per thousand, respectively. Biodegradation of BBP was fitted to the first-order kinetics model. The process of BBP biodegradation was monitored by reversed-phase high-performance liquid chromatography with ultra-violet detection after solid-phase extraction. The major metabolites of BBP degradation were identified as mono-butyl phthalate, mono-benzyl phthalate, phthalic acid, and benzoic acid by gas chromatography-mass spectrometry. BBP-degrading activity of P. fluorescens B-1 was found mostly in the soluble fraction associated with the smaller fragments of cellular membranes. Results suggest that mineralization of BBP can be achieved by microorganism of the mangrove environment.
authors.affiliation: Laboratory of Environmental Microbiology and Toxicology, Department of Ecology & Biodiversity, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, People's Republic of China.
authors.forename: Xiang-Rong
authors.initials: XR
authors.lastname: Xu
authors.forename: Hua-Bin
authors.initials: HB
authors.lastname: Li
authors.forename: Ji-Dong
authors.initials: JD
authors.lastname: Gu
mesh_terms: D001565:Benzoates / Q000378:metabolism; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D052244:Endocrine Disruptors / Q000378:metabolism*; D004734:Energy Metabolism; D008401:Gas Chromatography-Mass Spectrometry; D019015:Geologic Sediments / Q000382:microbiology*; D006723:Hong Kong; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008954:Models, Biological; D010795:Phthalic Acids / Q000378:metabolism*; D011551:Pseudomonas fluorescens / Q000201:enzymology / Q000302:isolation & purification / Q000378:metabolism*; D043982:Rhizophoraceae; D012965:Sodium Chloride / Q000378:metabolism; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D013696:Temperature; D053833:Wetlands
chemical_list: D001565:Benzoates; D052244:Endocrine Disruptors; D010795:Phthalic Acids; D012989:Soil Pollutants; D012965:Sodium Chloride; D002244:Carbon; C027561:butylbenzyl phthalate