Synergistic Antibacterial Activity of Medicinal Plant Extracts Combined with Conventional Antibiotics Against Multidrug-Resistant Bacteria

Vijay kantilal Bhavanani; Pramod kumar Mahour

doi:10.69968/ijisem.2026v5i2322-333

Authors

Vijay kantilal Bhavanani PhD Research scholar, Department of Chemistry, Monark University, Ahmedabad, India (vijaybhavanani007@gmail.com)
Pramod kumar Mahour Research Supervisor, Department of Chemistry, Monark University, Ahmedabad, India

DOI:

https://doi.org/10.69968/ijisem.2026v5i2322-333

Keywords:

Antimicrobial resistance, Multidrug-resistant bacteria, Medicinal plant extracts, Antibiotic synergy, Methicillin-resistant Staphylococcus aureus, Escherichia coli

Abstract

The rise of antimicrobial resistance (AMR) in recent years and the failure of sensitivity of traditional antibiotics, has made the multi-drug resistant (MDR) bacterial pathogens a global threat. In the present study, the synergistic antibacterial effects of some medicinal plants extracts and conventional antibiotics against MDR bacteria such as MDR (methicillin-resistant) Staphylococcus aureus and MDR (multi-drug resistant) of Escherichia coli strains was studied. The choice of medicinal plants namely Azadirachta indica (Neem), Ocimum sanctum (Tulsi), Allium sativum (Garlic), Curcuma longa (Turmeric) and Camellia sinensis (Green tea) was based on their antimicrobial activity reported in the literature. The extracts of these plants were prepared in aqueous, ethanolic and methanolic extracts to perform phytochemical testing for classification of alkaloids, flavonoids, tannins, saponins and phenol.

The antibacterial activity of the plant extracts and antibiotics was checked by the agar well diffusion test and minimum inhibitory concentration (MIC) measurement. The synergistic interactions between Plant extracts and antibiotics were performed using checkerboard assay and Fractional Inhibitory Concentration Index (FICI) technique. Results indicated that the selected plant extracts have good preliminary antibacterial results against MDR strains of bacteria. Methanolic and ethanolic extracts appeared to exhibit the highest inhibitors activity as compared to that of aqueous extracts. The improvement of inhibition zones and significant reduction in the minimal inhibition concentrations (MIC) were observed with combination therapy of medicinal plants extracts and antibiotics. Combination of Neem and ciprofloxacin was found to be showing more synergism with FICI value while combination of green tea and gentamicin had shown significant synergism with FICI value.

The results revealed that the medicinal plants extracts could improve the antibiotic property and could serve as strong adjuvants with antibiotic drugs for the pathogens of MDS. Overall, this research highlights the potential of combination therapy using plants to counteract antimicrobial resistance and to reduce the use of antibiotics. There is a need for further research in-vivo and clinical in order to validate them for their safety and efficacy expected clinical trial use.

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