Investigation of Antibacterial Potential of Bacillus and Actinomycetes Isolated from Soil Against Drug-resistant Clinical Isolates
DOI:
https://doi.org/10.4314/ajtmbr.v8i1.6Keywords:
Actinomycetes, antibacterial activity, clinical isolates, multidrug resistant, UV inductionAbstract
Background: Bacillus and Actinomycetes are well-known antibiotic-producing soil isolates. However, there is limited information on their activity against drug-resistant clinical isolates from Nigeria. This study aimed to investigate the antibacterial potential of Bacillus and Actinomycetes isolated from soil against drug-resistant clinical isolates.
Methods: Soil samples were collected from the rhizosphere of mango trees within Caleb University, Lagos, between January and March 2024. Targeted isolation of Bacillus and Actinomycetes was performed, and clinical isolates of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi were subjected to antibiotic susceptibility testing. The crowded plate method screened for antibiotic-producing isolates, and UV-induced mutation (2-hour and 4-hour exposures) was applied to assess changes in antibacterial activity.
Results: Bacillus species (71.4%) were the most prevalent soil isolates. All clinical isolates showed multidrug resistance. Before UV exposure, only Actinomycetes exhibited antibacterial activity against Pseudomonas aeruginosa and E. coli. After UV exposure, all soil isolates showed inhibitory activity against at least one clinical isolate.
Conclusion: The antibacterial activity of antibiotic-producing soil bacteria can be enhanced through UV induction, suggesting a promising strategy for developing new antimicrobial compounds.
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Data Availability Statement
Data supporting the findings of this study are available from the corresponding author upon reasonable request.
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