SCREENING AND CHARACTERIZATION OF POTENTIAL CYPERMETHRIN-DEGRADING BACTERIA VIA PHENOTYPIC AND MOLECULAR TECHNIQUES

Abstract

The need for sustainable management of cypermethrin, a widely used synthetic pesticide with significant ecological impact, calls for urgent concerns among environmental stakeholders. Therefore, in this study, the potential cypermethrin-degrading (PCD) bacteria were screened and identified from the soil samples collected from the Cowpea farm of Teaching and Research farm of Kwara State University, Nigeria. The bacterial strains were screened and isolated through enrichment techniques and identified using the standard phenotypic and molecular techniques. The potential for cypermethrin utilisation was determined in the cypermethrin-treated mineral salt medium. The three PCD bacterial strains isolated were PCD1 (Lysinibacillus fusiformis), PCD2 (Bacillus sonorensis), and PCD3 (Achromobacter sp.). Molecular characterization confirmed the identities and revealed high sequence similarity with known species. The accession numbers for these strains are MF973057 (PCD1), MF973058 (PCD2), and MF973059 (PCD3). The growth-dependent utilization of cypermethrin using the optical density values (OD 600 nm) showed the highest OD value on day six (PCD2: 0.60 and PCD3: 0.65) and day nine (PCD1: 0.80) respectively. The observed increases in optical density (OD 600 nm) affirmed their potential for cypermethrin degradation. While the strains exhibit promise in metabolizing cypermethrin, further research is needed to assess their suitability for bioremediation.