IN VITRO EVALUATION OF ANTIBACTERIAL, ANTIFUNGAL, AND ANTIBIOFILM ACTIVITIES OF POLYGALA MYRTIFOLIA LEAF EXTRACT

Abstract

Plants produce secondary metabolites that play key roles in adaptation and defense. Among these, saponins, xanthones, and alkaloids are notable for their antimicrobial and biomedical significance. Polygala myrtifolia is rich in these compounds and exhibits strong antimicrobial potential. Antimicrobial analyses demonstrated that the extract was effective against both Gram (+) and Gram (-) bacteria strains. MIC and MBC results indicated that K. aerogenes and E. durans were inhibited at 125 ppm, suggesting strong bactericidal activity. In antifungal assays, the extract inhibited the growth of Candida albicans and Candida utilis, with the highest activity observed at 1000 mg/mL. However, the lack of a linear concentration–response relationship indicates that the antifungal effect may be influenced by factors such as compound diffusion and interactions. Antibiofilm analysis revealed high levels of inhibition (85–90%) across all tested bacterial strains at higher concentrations (500–250 µg/mL), with E. coli and B. subtilis showing the greatest sensitivity. Overall, the results indicate that P. myrtifolia has considerable potential as a natural source for the development of antimicrobial and antifungal agents. These findings also provide a basis for future molecular studies aimed at identifying the active constituents responsible for its biological activity and further support the therapeutic value of plant-derived compounds.

Keywords

• Antifungal effect
• Antimicrobial activity
• Biofilm inhibtion
• Polygala myrtifolia

Project Number

1919B012408911

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