Antibiotic Susceptibility Profile of Soil-Borne Microorganisms Isolated from Selected Dump-sites in Ogbomoso, Oyo State

Abstract

Due to the lack of a leachate collection mechanism at most dump-sites waste is known to be a source of soil pathogens. This study aimed to detect microorganisms in dump-site soils coupled with testing the susceptibility of the detected microorganisms to selected antibiotics Soil samples were collected from five separate dump-sites in Ogbomoso, Oyo State, Nigeria. From the soil samples that were collected, eight species of bacteria and eight species of fungi were isolated. The bacterial and fungal derived from the collected soil samples were tested for antibiotic susceptibility using the conventional disc diffusion method. Results obtained indicate that the microbial loads varied between 1.7 and 4.8 x 105 CFU/g for fungal isolates while it varied from 1.0 to 8.0 x 105 CFU/g for bacterial population. Fungal isolates;Alternaria alternata, Candida albicans, Rhodotorula minuta, Fusariun oxysporum, Aspergillus flavus, Aspergillus tamarii, Fusarium solani and Penicillium digitatum were detected while bacterial isolates; Bacillus subtilis, Bacillus cereus, Staphylococcus epidermis, Clostridium sp., Acetobacter sp., Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa were equally detected from the dump-sites’ soil samples. The bacterial species tested were completely resistant to cefuroxime, but completely susceptible to gentamicin and ofloxacin. At varying doses, the fungal isolates demonstrated resistance to and susceptibility to griseofulvin, itraconazole, and ketoconazole.Based on the results of this study, antibiotics such as gentamicin and oflaxacin should be considered first line of defense against infections caused by both soil-borne Gram-positive and Gramnegative bacteria