Prevalence of Beta-Lactamase Producing Enterobacteriaceae Isolated from Ready-To-Eat Vegetables in Benin City, Nigeria.

Ready-to-eat (RTE) vegetables are increasingly consumed in Nigeria due to their nutritional benefits, but their raw nature make them vulnerable to microbial contamination. The rising occurrence of β-lactamase-producing Enterobacteriaceae, which limits effective antibiotic treatment, is a growing public health concern. This study investigated the prevalence of beta-lactamase-producing Enterobacteriaceae in commonly consumed RTE vegetables sold in Benin City, Nigeria. Fresh samples of cabbage, carrot, and cucumber were randomly collected from Oba and Ogba markets, processed by washing, and bacterial enumeration was performed using the spread plate method. Isolates were identified to genus and species level based on colonial morphology, Gram staining, and biochemical tests, and screened for beta-lactamase production using the combined disc synergy test. Data were analysed using SPSS version 27, and results were presented using descriptive statistics and Chi-square test. A total of 169 Enterobacteriaceae isolates were recovered, with Escherichia coli being the most predominant (52.1%), followed by Proteus mirabilis (13.6%), Klebsiella spp. (12.4%), Enterobacter aerogenes (7.1%), Serratia marcescens (6.5%), Salmonella typhi (4.7%) and Citrobacter freundii (3.6%). Beta-lactamase production was detected in 42.6% of the isolates, with the highest prevalence observed in Klebsiella spp. (76.2%) and Proteus spp. (60.9%), while Serratia marcescens (9.1%) and Citrobacter freundii (16.7%) showed the lowest prevalence. There was a significant association between bacterial species and beta-lactamase production (p = 0.001). The results indicate significant contamination of RTE vegetables with antibiotic-resistant Enterobacteriaceae, highlighting a potential risk for transmission of antimicrobial resistance and foodborne infections to consumers.