Bioactive compounds from fermented leaf: Potent antibiotics against multidrug-resistant and .

Unlabelled: Antibiotic resistance microorganisms (ARMs), particularly gram-negative bacteria, pose a global health threat. The effects of fermentation on phytochemicals are numerous, and exploring this potential is the focus of drug development. The study investigated the role of fermentation in modifying leaf secondary metabolites as an effective antibiotic against . This work showed that fermentation increased the content of lycopene, flavonoid and carotenoid compounds but decreased chlorophyll, soluble protein and phenol. Pearson's correlation showed a strong correlation between microbial activities and secondary metabolic changes. The methanolic extract of fermented leaf pulp (at day 9) showed significant antioxidant and anti-inflammatory activities. The GCMS and FTIR results showed unique compounds and structural modifications at different intervals of the fermentation period. analyses showed that fermentation did not alter the inhibition rate against however, were significantly inhibited by fermented V. amygdalina pulp extracts. analyses showed that 4,6-Cholestadien-3β-ol- a compound present only on the ninth day of fermentation-was responsible for the inhibition of the gram-negative bacteria via the substitution of multiple non-ionic interactions of some key catalytic site residues with non-ionic types, thereby denying ionisation and salt-bridge properties that porins explore to resist antibiotics; and higher binding affinity to OmpC and OmpF than ampicillin. Therefore, this steroid-derived compound may open a new pipeline for developing ion-independent multi-target antibiotics against broad-spectrum multidrug-resistant gram-positive and gram-negative bacteria in food and pharmaceutical purposes.

Supplementary Information: The online version contains supplementary material available at 10.1007/s40203-024-00277-2.