Isolation of Dibutyl Phthalate-Degrading Bacteria and Its Coculture with Citrobacter freundii CD-9 to Degrade Fenvalerate

Abstract

Continued fenvalerate use has caused serious environmental pollution and requires large-scale remediation. Dibutyl phthalate (DBP) was discovered in fenvalerate metabolites degraded byCitrobacter freundii CD-9. Coculturing is an effective method for bioremediation, but few studies have analyzed the degradation pathways and potential mechanisms of cocultures. Here, a DBPdegrading strain (BDBP 071) was isolated from soil contaminated with pyrethroid pesticides (PPs) and identified as Stenotrophomonas acidaminiphila. The optimum conditions for DBP degradation were determined by response surface methodology (RSM) analysis to be 30.9 mg/l DBP concentration, pH 7.5, at a culture temperature of 37.2°C. Under the optimized conditions, approximately 88% of DBP was degraded within 48 h and five metabolites were detected. Coculturing C. freundii CD-9 and S. acidaminiphila BDBP 071 promoted fenvalerate degradation. When CD-9 was cultured for 16 h before adding BDBP 071, the strain inoculation ratio was 5:5 (v/v), fenvalerate concentration was 75.0 mg/l, fenvalerate was degraded to 84.37 ± 1.25%, and DBP level was reduced by 5.21 mg/l. In addition, 12 fenvalerate metabolites were identified and a pathway for fenvalerate degradation by the cocultured strains was proposed. These results provide theoretical data for further exploration of the mechanisms used by this coculture system to degrade fenvalerate and DBP, and also offer a promising method for effective bioremediation of PPs and their related metabolites in polluted environments.

State epizootic monitoring of contagious diseases of bees in the territory of the Volyn region

“…For example, in addition to bacterial diseases of bees, bee bacteriosis (infection with bacteria of the family Enterobacteriaceae of the genera Salmonella, Klebsiella, Enterobacter, Citrobacter, etc.) also causes a decrease in the productivity of bee colonies (Galatiuk et al, 2020a;Galatiuk et al, 2020c;Wu et al, 2022). Improving the state monitoring and analysis system regarding the occurrence of this or that bee disease is an essential step toward the European integration of Ukraine.…”

Degradation of Triazole Fungicides by Plant Growth-Promoting Bacteria from Contaminated Agricultural Soil

“…These functionalities contribute to promoting plant growth and soil health, making them valuable assets for improving agricultural productivity and sustainability. However, effective biodegradation with these microbes depends on specific environmental conditions, and completing the degradation of pollutants using a single strain is challenging [ 32 , 33 ]. Pesticides can be complex and persistent by accumulation in the long term, and relying on a single microbial strain may not provide sufficient metabolic diversity or enzymatic capacity to fully degrade them.…”

“…The co-culturing of microbial consortiums or combinations of different strains can increase the adaptability of the consortiums to varying environmental conditions and enhance their efficacy in degrading a wide range of pollutants, proving to be more effective than a single-strain approach [ 21 , 24 , 29 , 34 ]. For example, co-cultures of two bacterial isolates have been reported to significantly improve fungicide degradation in vitro [ 33 ] or in field soils [ 35 ].…”