Synergistic antimicrobial potential of Ziziphus jujube and Ziziphus oenoplia extracts combined with ciprofloxacin against multidrug-resistant strains

Abstract

Background: The combined use of herbal medicines and first-line antimicrobial agents, to which many pathogens have developed resistance, is considered a practical strategy for managing polymicrobial infections and limiting the emergence of antimicrobial-resistant strains. Objective: The emergence of antimicrobial resistance has increased interest in plant-derived compounds as adjuncts to conventional antibiotics. This study evaluated the in-vitro antimicrobial activity of Ziziphus species extracts and their synergistic interaction with Ciprofloxacin against multidrug-resistant bacteria. Methods: Ethanolic extracts of Ziziphus jujuba and Ziziphus oenoplia were tested against Staphylococcus aureus (MTCC-7443), Bacillus subtilis (MTCC-121), Salmonella typhi (MTCC-733), and Pseudomonas aeruginosa (MTCC-1036). Antimicrobial activity was evaluated using inhibition zone and minimum inhibitory concentration (MIC) assays. Results: The extracts exhibited varying degrees of antimicrobial activity against all tested strains. EEZO showed the highest activity against S. typhi with an MIC value of 65.81 ± 0.02 µg/mL, while AEZO exhibited the lowest activity against S. aureus (MIC: 28.97 ± 0.021 µg/mL). The combination of EEZO with Ciprofloxacin produced enhanced inhibitory activity against S. typhi and S. aureus, demonstrating synergistic interactions. Conclusion: Ziziphus species extracts demonstrated notable antimicrobial activity and enhanced the efficacy of Ciprofloxacin against multidrug-resistant bacterial strains.