Abstract

Introduction: Solid waste generation and disposal remain major global environmental and public health concerns.
Aim: This study assessed the antibiotic susceptibility and molecular characteristics of bacteria isolated from solid waste disposal sites.
Methods: Soil samples were collected from two depths (0–30 cm and 30–60 cm) at waste dumpsites and analyzed using standard bacteriological methods. Antibiotic susceptibility testing was performed using the disc diffusion technique, while molecular characterization was carried out using a PCR-based approach.
Results: A total of 50 bacterial isolates were obtained and phenotypically identified as belonging to six genera: Bacillus, Staphylococcus, Shigella, Salmonella, Pseudomonas, and Klebsiella. Antibiotic susceptibility profiles revealed that 30.4% of Bacillus spp. were resistant to Zinnacef (cefuroxime), 11.8% of Staphylococcus spp. showed resistance to septrin, 25% of Salmonella and 33.3% of Shigella isolates were resistant to augmentin and gentamicin, respectively, while 50% of Pseudomonas spp. were sensitive to gentamicin. All Klebsiella isolates (100%) were susceptible to all tested antibiotics. Haemolytic assays indicated that 22%, 42%, and 36% of isolates exhibited α-, β-, and γ-haemolysis, respectively. Molecular characterization showed 91.52% pairwise identity between Bacillus spp. and Bacillus amyloliquefaciens (NCBI accession HQ021420.1), 92.45% similarity between Pseudomonas spp. and Pseudomonas aeruginosa (MF144446), and 96.7% similarity between Salmonella spp. and Salmonella enterica (CP028131).
Conclusion: The study revealed the genomic identity and antibiotic resistance patterns of bacterial species present in solid waste-impacted soils within a tertiary institution. The findings underscore the importance of proper waste management to reduce the risk of bacterial transmission and environmental contamination.

Key words: Antibiotics, genomics, solid waste, tertiary institution, susceptibility