Antibiogram of bacterial flora of public health significance associated with postharvest Irvingia gabonensis seeds in Lagos State, Nigeria

Abstract

The spread of resistant bacteria within the community has continually posed obvious additional problems for infectious control. Efforts to identifying sources of resistant bacteria have not been channeled towards medicinal food condiments. This study investigated the antibiogram of bacterial flora of public health significance associated with postharvest Irvingia gabonensis seeds in Lagos State, Nigeria. The blended, homogenized and serially diluted samples of I. gabonensis seeds were plated using the spread plate technique on selective and differential agar media. API 20E and API 20NE were used for identification of members of Enterobacteriaceae and non-Enterobacteriaceae, respectively. The agar disc-diffusion method was employed to determine the antibiotic resistance profiles of the isolates. A total of 263 bacterial isolates (129 Gram-positive and 134 Gram-negative) were encountered. Eighty-five (66%) of Gram-positive isolates exhibited resistance to penicillin, gentamicin 65 (50.4%), erythromycin 69 (53.5%), cloxacillin 63 (43.8%), chloramphenicol 73 (56.6%), amoxicillin 75 (58.1%), tetracycline 58 (45%) while 69 (53.5%) showed resistance to streptomycin. However, 87 (65%) of Gram-negative bacterial strains exhibited resistance to cloxacillin, ceftazidime 82 (61.2%), ciprofloxacin 67 (50%), gentamicin 77 (57.5%), cefotaxime 74 (55.2%), augmentin 84 (62.7%), nitrofuratoin 61 (45.5%) and 24 (17.9%) to ofloxacin. This study showed that I. gabonensis seeds could be a source of antibiotic-resistant bacterial strains, despite its enormous medicinal properties, which is a threat to public health. The antibiotic resistance patterns of isolated bacterial strains are of medical importance as there are chances of transferring resistant traits.