Biodegradation potential of 2,4 dichlorophenoxyacetic acid by Cupriavidus campinensis isolated from rice farm cultivated soil

Abstract

This study was carried out for nine months to find bacterial strain capable of mineralizing 2,4-dichlorophenoxyacetic acid herbicide. A popular pre-/post emergent systemic herbicide known as 2, 4-dichlorophenoxyacetic Acid (2,4-D) is used to combat broad-leaved weeds and other plants on rangelands that are specifically intended to boost agricultural productivity and reduce losses the result of crop pests on agricultural products. This study's objective is to isolate, screen, and identify 2, 4-dichlorophenoxyacetic Acid degrading microorganisms from rice-growing soil in Kura local government area, Kano State. Experiments with incubation in mineral broth allowed for the isolation of 2, 4-dichlorophenoxyacetic Acid degrading bacteria. 2,4-dichlorophenoxyacetic Acid herbicide is added to salt medium. A native bacterial strain that can use 2, 4-dichlorophenoxyacetic Acid as its only source of carbon and energy was found in the soil of a rice field with a lengthy history of herbicide use. All the experiments were carried out in triplicates. Additionally, employed for data display were graphs and tables. An indigenous bacterial strain that is capable of 2,4-dichlorophenoxyacetic Acid supplementation in minimal salt medium were isolated from using 2,4-dichlorophenoxyacetic acid as the main alternative for energy and carbon from Rice cultivated lands. The strain named B3-BUK-BCH was recognized as Cupriavidus campinensis based on the analysis of sequence of 16S ribosomal RNA, morphological, and chemical features. The mineralization features of isolated B3-BUK-BCH was quantified using one factor at a time approach. The optimal conditions for 2,4-dichlorophenoxyacetic Acid degradation were as follows: pH 7, temperature 40 °C, 200 gL−1inoculum size, and 0.72 gL−1 of 2,4-D concentration. High-performance liquid chromatography (HPLC) was used to test the 2,4-D's propensity for degradation. Under ideal circumstances, up to 94.69% of the 2,4-D was degraded after 6 days of incubation, this isolate had never been reported as able to degrade 2,4-D based on the available literature in the study area. The isolated strain represents a great potential for bioremediation.

Keywords

• 2,4-dichlorophenoxyacetic acid
• Bioremediation
• Pesticides
• Cupriavidus campinancis
• Rice cultivated soil