ANTIBACTERIAL ACTIVITY OF ALLIUM SATIVUM (GARLIC) AGAINST NEISSERIA GONORRHOEAE AND TREPONEMA PALLIDUM
DOI:
https://doi.org/10.33003/fjs-2026-1001-4542Keywords:
Allium sativum, Garlic, Neisseria gonorrhoeae, Treponema pallidum, Antibacterial activity, Minimum Inhibitory Concentration (MIC), GC-MS, PhytochemicalsAbstract
Background: The emergence of multidrug-resistant strains of Neisseria gonorrhoeae and Treponema pallidum, the causative agents of gonorrhea and syphilis, necessitates the search for novel therapeutic agents . Allium sativum (garlic) has a long history of use in traditional medicine for its broad-spectrum antimicrobial properties. This study aimed to investigate the in vitro antibacterial activity of garlic extracts against clinical isolates of N. gonorrhoeae and T. pallidum. Fresh garlic juice was extracted and its phytochemical constituents were analyzed using Gas Chromatography-Mass Spectrometry (GC-MS). The antibacterial activity was evaluated using the agar well diffusion method (6 mm well diameter) to determine the zones of inhibition, and the broth dilution method was used to determine the Minimum Inhibitory Concentration (MIC). Concentrations of 25, 50, 75, and 100 mg/mL were tested. GC-MS analysis revealed 27 bioactive compounds. The major constituents were n-Hexadecanoic acid (25.72%), Oleic Acid (21.56%), and Hexadecanoic acid, ethyl ester (10.87%). The garlic extract demonstrated significant dose-dependent antibacterial activity against both pathogens. The highest zone of inhibition (16 mm) was observed at 100 mg/mL for N. gonorrhoeae. The MIC results indicated that the extract completely inhibited the growth of N. gonorrhoeae at 75 mg/mL and T. pallidum at 100 mg/mL. The findings confirm that Allium sativum possesses potent antibacterial activity against Neisseria gonorrhoeae and Treponema pallidum. It represents a promising candidate for developing alternative or adjunctive therapies against these antibiotic-resistant sexually transmitted infections.
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