In vitro Antibacterial Activity of Mulberry Fruit Extracts from Different Accessions against Salmonella enterica and Bacillus cereus

The emergence of antibiotic-resistant foodborne pathogens, particularly Salmonella enterica and Bacillus cereus, highlights the necessity for efficient natural antibacterial alternatives. The present study evaluated the in vitro antibacterial efficacy of aqueous fruit extracts from five mulberry (Morus spp.) accessions (MI-0789, MI-0632, MI-0489, MI-0300 and MI-0783) against these pathogens. Extracts were evaluated at doses ranging from 20 to 100 µL utilizing the agar well diffusion method, with inhibition zones recorded following 24- hour incubation at 37 °C. The results demonstrated significant changes in antibacterial activity that were depending on genotype and concentration. MI-0300 demonstrated enhanced efficacy against both Salmonella enterica (25 mm at100 µL) and Bacillus cereus (38 mm at 100 µL), exhibiting significant activity even at reduced dosages. MI-0783 and MI-0789 exhibited moderate activity, but MI-0632 and MI-0489 shown weak or negligible inhibition. The observed differences are due to variances in phytochemical composition, specifically phenolics, flavonoids and anthocyanins. These findings underscore MI-0300 as a potential candidate for the development of natural antibacterial agents, functional foods and nutraceutical products.