Biodegradation kinetics of 2,4-D by bacterial strains isolated from soil

Abstract

The aim of the study was to characterize the 2,4-dichlorophenoxyacetic acid (2,4-D) degradative potential of three bacterial strains identified by MIDI-FAME profiling as Burkholderia cepacia (DS-1), Pseudomonas sp. (DS-2) and Sphingomonas paucimobilis (DS-3) isolated from soil with herbicide treatment history. All strains were capable of using herbicide as the only source of carbon and energy when grown in mineral salt medium (MSM) containing 2,4-D (50 mg/l). Over a 10 day incubation period, 69%, 73% and 54% of the initial dose of 2,4-D were degraded by strains DS-1, DS-2 and DS-3, respectively. Analysis of 2,4-dichlorophenol (2,4-DCP) concentration, the main metabolite of 2,4-D degradation, revealed that strains DS-1 and DS-2 may also have the potential to metabolize this compound. The percentage of 2,4-DCP removal was 67% and 77% in relation to maximum values of 9.5 and 9.2 mg/l determined after 4 and 2 days for MSM+DS-1 and MSM+DS-2, respectively. The degradation kinetics of 2,4-D (50 mg/kg) in sterile soil (SS) showed different potential of tested strains to degrade 2,4-D. The times within which the initial 2,4-D concentration was reduced by 50% (DT50) were 6.3, 5.0 and 9.4 days for SS+DS-1, SS+DS-2 and SS+DS-3, respectively.

Functional Diversity of Soil Microbial Communities in Response to the Application of Cefuroxime and/or Antibiotic-Resistant Pseudomonas putida Strain MC1

“…For example, a study by Cycoń et al [9] showed that the antibiotic-resistant strain of Citrobacter freundii did not affect the catabolic activity and functional diversity of the soil microorganisms whether it was introduced alone or in combination with vancomycin. This phenomenon may be related to the survivability of the inoculants in the soil environment, which is often a foreign environment for them [46]. Soil is a very complex ecosystem and many biotic and abiotic factors may determine the survival of the inoculants.…”

“…The concentrations of XM reflect the adverse scenarios associated with the entry of large quantities of antibiotics into the soil as a result of the uncontrolled disposal of unused drugs into municipal waste or depositing them in landfills. The experiment used MC1 (accession number in GenBank: MC327770), which was isolated from raw sewage in the presence of cefuroxime [43,45] and identified as Pseudomonas putida based on the analysis of the 16S RNA gene [45] and biochemical properties [46]. In addition, the strain MC1 was characterized by resistance to cefuroxime, clindamycin, erythromycin and vancomycin with MIC values above 256 µg/mL [43].…”

Biodegradation of 2,4-dichlorophenoxyacetic acid and 4-chlorophenol in contaminated soils by <i>Pseudomonas fluorescens</i> strain HH

“…2,4D exists predominantly as an anion which is adsorbed to positively charged sites on the edges of clay particles in soil preventing its cellular uptake and biodegradation (McGhee et al, 1999). The degradation of 2,4D in soil has been investigated in various laboratories (Jacobsen & Pedersen, 1991;Bryant, 1992;Balajee & Mahadevan, 1993;Entry et al, 1996;Chang et al, 1998;Cycoń et al, 2011;Musarrat et al, 2000;Chang et al, 2016;Xia et al, 2017). However, the degradation of 2,4D in various soil with different physico-chemical properties has not been conducted extensively.…”

Effect of propanil, linuron, and dicamba on the degradation kinetics of 2,4‐dichlorophenoxyacetic acid by Burkholderia sp. A study by differential analysis of 2,4‐dichlorophenoxyacetic acid degradation data

“…To describe the microbial degradation of organic compounds in soils and bioreactors, the batch experimental data are usually described by first order models [22][23][24]. Although this approach could be applied to compounds not supporting growth or to abiotic pesticide degradation kinetics, when an organic compound is microbiologically degraded, frequently the kinetic behavior diverges from first or pseudo-first kinetics, and in many biodegradation experiments, a sigmoidal decay in the compound concentration is observed [25][26][27][28][29][30][31]. In this case, the peak degradation rate is reached at a value corresponding to the inflection point of the curve.…”