Isolation of indigenous soil bacteria with potential application for diuron removal

Abstract

Diuron is a widely used herbicide in sugarcane, cotton, coffee, and citrus production and is classified as a priority pollutant. Physical and chemical remediation of pesticide-contaminated sites is often technically complex and costly. Microorganism-mediated bioremediation offers an environmentally compatible and cost-effective alternative, particularly when pollutant-specific indigenous microorganisms are used. In this study, microorganisms were isolated from diuron-amended soil microcosms, and their diuron removal capacities were evaluated under different pH and temperature conditions. Fourteen bacterial isolates were initially screened, of which six capable of growing in diuron-supplemented medium were selected. Isolates 2 and 6 achieved the highest removal efficiencies, reaching 53% and 51%, respectively, within 3 days. A mixed microbial culture achieved 60% removal, suggesting potential complementary interactions among the isolates. Based on 16S rRNA gene sequencing, isolate 2 showed 97–99% sequence identity to Bacillus sp., whereas isolate 6 showed 97–99% identity to Cellulomonas sp. The study aimed to identify bacterial strains with potential application in future pesticide bioremediation. Indigenous isolates with high pollutant-removal capacity may improve bioremediation performance in their native environments because they are adapted to prevailing local conditions.