title: Enantioselective separation and degradation of the herbicide dichlorprop methyl in sediment.
abstract: Chiral pesticides currently constitute about 50% of all pesticides dosage used in China, and this ratio is increasing as more complex structures are introduced. Dichlorprop methyl (DCPPM) is a chiral herbicide consisting of a pair of enantiomers. In this study, the enantiomeric separation of DCPPM was investigated by gas chromatography (GC) and high-performance liquid chromatography (HPLC) using chiral stationary phases (CSPs), and its enantiomeric degradation was characterized using a DCPPM-degrading bacterial strain isolated from an activated sludge from a textile-printing wastewater treatment plant. Baseline separation by both GC and HPLC was achieved. Incubation with DCPPM-degrading bacteria in different pH solutions showed that the R enantiomer was preferentially degraded over the S enantiomer of DCPPM. The degradation rate constant decreased with increasing pH in the order of k(pH5) approximately k(pH7) >k(pH9). In comparison, the enantioselectivity as indicated by EF followed the order of pH 7 > pH 9-pH 5.
authors.affiliation: Research Center of Green Chirality, College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou, People's Republic of China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Ma
authors.forename: Chao
authors.initials: C
authors.lastname: Xu
authors.forename: Yuezhong
authors.initials: Y
authors.lastname: Wen
authors.forename: Weiping
authors.initials: W
authors.lastname: Liu
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D001673:Biodegradation, Environmental; D002021:Buffers; D002849:Chromatography, Gas / Q000379:methods; D002851:Chromatography, High Pressure Liquid; D004785:Environmental Pollutants / Q000032:analysis; D006540:Herbicides / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D010575:Pesticides / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D013237:Stereoisomerism; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis; D018508:Water Purification
chemical_list: D002021:Buffers; D004785:Environmental Pollutants; D006540:Herbicides; D010575:Pesticides; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D015084:2,4-Dichlorophenoxyacetic Acid; C101283:dichlorprop methyl ester