Assessment of Microbiological Proliferation and in Vitro Demonstration of the Antimicrobial Activity of the Commonly Available Salad Vegetables within Dhaka Metropolis, Bangladesh

Abstract

Present study mapped a complete pathogenic profile of the salad vegetables in Dhaka Metropolis, Bangladesh. In addition to a huge bacterial load found previously in lettuce, tomato, cucumber and carrot, current study further detected microbial contamination in chili, onion, capsicum and coriander samples. While Vibrio spp., Salmonella spp. and Shigella spp. fecal coliform and Eshcherichia coli were found to be absent within these vegetable samples; a colossal burden of Aeromonas spp. (>106 cfu/g) was observed in chili, capsicum, coriander, whereas Staphylococcus aureus (1.2×108 cfu/g) and Klebsiella Pneumoniae (104 cfu/g) were detected in onion. Fungal growth was also observed in all samples. Most of the pathogens from all 8 samples were resistant against erythromycin (15 µg), amoxicillin (30 µg) and ampicillin (10 µg) while susceptible against ciprofloxacin (5 µg), kanamycin (30 µg) and gentamicin (10 µg). Interestingly, lettuce and cucumber samples were found to exhibit the anti-bacterial activity against Staphylococcus aureus and Aeromonas spp.