Enantioselective biodegradation and enantiomerization of dichlorprop in soils

Copyright © 2020 Elsevier Ltd. All rights reserved..

The dissipation of racemic, R-, and S- dichlorprop (DCPP) in four soils were studied in the laboratory. The half-lives of racemic DCPP were from 10.5 to 19.8 days. Preferential degradation of R- or S-DCPP was detected in all soils, even in one soil that the apparent enantiomeric fraction remained constant during incubation. The enantiomerization of DCPP was found to proceed in both directions, except in forest soil that no enantiomerization of S- to R-DCPP was observed. The isomerization equilibrium constant (K = kRS/kSR) in two vegetable soils were 0.54 and 0.53, respectively, favoring herbicidally active R enantiomer, while in paddy soil K was 1.60, favoring an inversion of R into S enantiomer. Real-time PCR showed that the rdpA gene was not detected in all indigenous and DCPP amended microcosms probably because of relative short incubation time and low amendment concentrations. In contrast, the sdpA gene was present in indigenous soils and significantly elevated after DCPP addition with the highest relative abundance around day 10 in all microcosms. Illumina sequencing of the 16S rRNA gene showed that the relative abundance of Proteobacteria significantly increased in all DCPP treated soils. DCPP-degrading related families, Sphingomonadaceae and Comamonadaceae, enhanced in all soils, while Burkholderiaceae elevated only in paddy soil with preferential degradation of S-DCPP and Pseudomonadaceae only in forest soil with R-enantiomer preference. The sdpA gene sequencing revealed that about 92%-99% of bacteria harboring sdpA genes in studied soils belong to Alphaproteobacteria.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:258

Enthalten in:

Chemosphere - 258(2020) vom: 15. Nov., Seite 127322

Sprache:

Englisch

Beteiligte Personen:

Youfeng, Zhu [VerfasserIn]
Dongdong, Zhang [VerfasserIn]
Ling, He [VerfasserIn]

Links:

Volltext

Themen:

2,4-Dichlorophenoxyacetic Acid
2577AQ9262
Dichlorprop
Enantiomerization
Enantioselective degradation
Herbicides
Illumina sequencing
J7YV2RKO6Q
Journal Article
RNA, Ribosomal, 16S
RdpA and sdpA genes
Soil
Soil Pollutants

Anmerkungen:

Date Completed 28.09.2020

Date Revised 28.09.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.chemosphere.2020.127322

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM31142550X