Biofilm-associated gene markers of bacterial contaminants in ready-to-eat fresh fruit and vegetable cocktail in Portharcourt Metropolis, Rivers State, Nigeria

Aim: The increasing consumption of ready-to-eat fruit and vegetable (RTEFV) cocktails in both Nigeria and other countries underscores their importance to human health. This cross-sectional study evaluates the biofilm-associated gene markers of bacterial contaminants recovered/isolated from RTEFV cocktails in Port Harcourt metropolis. Methods: A total of 40 samples were collected once-off and subjected to laboratory-based microbiological analysis for bacterial culturomics, antibiotic susceptibility testing, and molecular biology detection studies. Results: The total heterotrophic bacterial count of fresh fruits and vegetable salad for all locations ranged from 1.12 × 105 CFU/g to 9.58 × 105 CFU/g. Total coliform count on MacConkey, EMB (Eosin Methylene Blue Agar), SSAgar (Salmonella Shigella Agar), with all revealing a high density of potential enteric pathogens. The gene-based bacteriology revealed several biofilm-producing strains, including icaC (6/6; 100%) and AcrAB (4/6; 66.7%) pathogenic genes. Other related analysis showed identified bacterial genera including: Staphylococcus sp. (20.4%, n = 11), Escherichia coli (20.4%, n = 11), Bacillus sp. (7.4%, n = 4), Corynebacterium sp. (14.8%, n = 8), Klebsiella sp. (12.9%, n = 7), Pseudomonas sp. (11.1%, n = 6), Salmonella sp. (7.4%, n = 4), Micrococcus sp. (3.7%, n = 2), and Tatunella sp. (1.9%, n = 1) with high frequency of Staphylococcus sp. and Escherichia coli occurrence observed in assessed fresh-fruits. Staphylococcus sp. exhibited resistance to Ampiclox 10 (91%) while Bacillus sp. were highly susceptible to ciprofloxacin 0 (0) and levofloxacin 0 (0). E. coli demonstrated 100% resistance to Augmentin, Ceporex, and ampicillin, whereas Klebsiella sp. were sensitive to tarivid and ciprofloxacin. Molecular identification/phylogeny as well as associated accession numbers, confirmed strains 98–100% similarity with Escherichia coli (CP128912). Klebsiella variicola (CP124804), Proteus vulgaris (MF472597), Providencia stuartii (0N360674), and Morganella morganii (MF927500). The standard deviation and level of significance of reports were recorded at p < 0.05 for the applied ANOVA test. Conclusions: This study emphasizes basic epidemiological relevance and contamination risks associated with studied RTEFV cocktails, which may be associated with improper handling, highlighting the urgent need for enhanced hygienic practices among vendors/handlers and consumers with adroit compliance with stipulated fruit handling regulations.