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bioRxiv · 10.1101/2023.12.06.570382

A novel method of testing the antimicrobial potentials of Exiguobacterium aurantiacum, Lysinibacillus boronitolerans and Bacillus megaterium

Jain, R.·Shukla, V.·Lokur, A.·Belwalkar, M.·Rege, M.
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Abstract

Microorganisms can be an effective source for antimicrobial compounds including peptides that provide an evolutionary advantage to them in specific niches. Prior studies have noted the antimicrobial properties of Exiguobacterium aurantiacum, Lysinibacillus boronitolerans and Bacillus megaterium but they used time- and resource-intensive procedures to prepare the extracts (2, 10). We wanted to explore a more cost-effective, time-effective and simpler method of testing the antimicrobial potential of bacterial extracts. Our extraction protocol is a one-step incubation of the organism in the solvent overnight, followed by a standard well diffusion based assay to test its antimicrobial effect. We tested this method with three cultures isolated from the premises of Mumbai railway stations: E. aurantiacum, L. boronitolerans and Bacillus megaterium. These extracts were tested against human pathogens Staphylococcus aureus and Enterococcus faecalis. E. aurantiacum, L. boronitolerans and B. megaterium inhibited S. aureus by 9.17 {+/-} 0.42, 9.25 {+/-} 0.48 and 10.50 {+/-} 1.5 mm, respectively, and E. faecalis by 15.79 {+/-} 2.25, 14.21 {+/-} 0.88 and 17.5 {+/-} 2.89 mm, respectively. This approach is therefore suggested to be effective for screening the antimicrobial activity of these bacteria.

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Jain, R., Shukla, V., Lokur, A., Belwalkar, M., Rege, M.. 2023-12-07. A novel method of testing the antimicrobial potentials of Exiguobacterium aurantiacum, Lysinibacillus boronitolerans and Bacillus megaterium. https://doi.org/10.1101/2023.12.06.570382

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