Antimicrobial action of methanolic seed extracts of Syzygium cumini Linn. on Bacillus subtilis

Abstract

Phytochemicals of Syzygium cumini are used for the treatment of various diseases as a traditional medicine but the mechanism behind their action is not well reported. Antimicrobial activity of methanolic seed extract of S. cumini was done by agar well diffusion assay on Bacillus subtilis and its zone of inhibition was found to be 20.06 mm in comparison to control having no zone of inhibition. MIC of S. cumini was found to be 0.3 mg/ml. Genomic DNA degradation of B. subtilis reveals apoptosis and FE-scanning electron microscope indicates cell wall cracking on several intervals of time. Results of propidium iodide staining showed few bacterial cells were stained in control; however population of stained cells increased after exposing them for varying period of time. Flow cytometric kinetic data analysis on the membrane permeabilization in bacterial cell showed the significant contribution of antimicrobial potential of the seed extract on antimicrobial-induced permeabilization. In silico analysis revealed two components of S. cumini methanolic extract to be active against four enzymes (PDB ID—1W5D, 4OX3, 3MFD and 5E2F) which are crucial for plasma membrane synthesis in B. subtilis. Moreover lupeol showed highest binding energy for macromolecule 1W5D and 4OX3 forming one hydrogen bond each whereas stigmasterol showed the highest binding energy for macromolecule 3MFD and 5E2F forming four hydrogen bonds and alkyl bonds respectively. It demonstrates that methanolic seed extracts of S. cumini could be used for inhibition of food born infection caused by B. subtilis and also an alternative of prevalent antibiotics.

Susceptibility Assessment of Multidrug Resistant Bacteria to Natural Products

“…Using MIC and Triplex PCR showed the time-dependent effects of these agents on bacterial DNA, with the most pronounced effects observed at 72 hours of incubation, confirmed by the absence of bacterial DNA on an ethidium bromide stained gel (1%). A previous study that examined aqueous extract of S aromaticum induced DNA fragmentation in B subtilis at 24, 48, and 72 hours of incubation reported timedependent results 42 that coincide with our findings. This indicates that the aqueous extract of S aromaticum has a pronounced effect on the degradation of DNA of S aureus accompanied by inhibition of bacterial protein synthesis.…”

“…41 Other studies using field emission SEM reported that methanolic seed extracts of S cumini induced a significant variation in the size of Bacillus subtilis cells. 42 Scanning electron microscope analysis of the effects of treatment with quercetin showed that it exhibited antibacterial activity characterized by disruption of the integrity of the cell walls in both grampositive and gram-negative bacteria. 43 A bacterial apoptosis technique was used to assess the mode of action of the products tested.…”

Lactobacillus Paracasei Hii01 Mediated Fermentation of Syzygium Cumini L. Fruits: Assessment of Changes in Phenolic Content and Antioxidant Capacity

“…The methanolic seed extract of S. cumini has been reported for antimicrobial activity against Bacillus subtilis, and the activity was associated with damaging the cell wall, reduction in bacterial cell size, and leaking of cellular contents [19].…”

The ultrastructural damage caused by Eugenia zeyheri and Syzygium legatii acetone leaf extracts on pathogenic Escherichia coli

“…This was done as previously reported [30] with slight modifications. Briefly, the E. coli cells were grown in TSB for 18 h, washed twice with phosphate buffer saline (PBS) and then adjusted to 10 6 CFU/mL with PBS.…”