Abstract:
Oral candidiasis is a common opportunistic fungal infection, particularly among
immunocompromised individuals such as cancer patients. The emerging resistance
of Candida species to conventional antifungals highlights the urgent need for effective
and holistic alternatives. This study evaluated the in vitro anticandidal
activity of aqueous extracts of Aegle marmelos (leaf and fruit), Lawsonia inermis
(leaf), and Cinnamomum zeylanicum (leaf) and their effects on oral commensal
microorganisms. The minimum inhibitory concentrations (MICs) and minimum
fungicidal concentrations (MFCs) of the extracts were determined against eleven
clinically isolated Candida species, including fluconazole-resistant isolates, using
the broth microdilution method. The effect on oral commensals was assessed using
the agar well diffusion method with mixed cultures from oral rinse samples from
cancer patients and healthy individuals. All four plant extracts demonstrated
notable anticandidal activity, with C. zeylanicum showing the most potent and
consistent inhibition, followed by A. marmelos leaf extract, while L. inermis exhibited
moderate activity. MIC values of the plant extracts ranged between 0.016–
1.000 mg/mL, comparable in some cases to fluconazole, and all extracts effectively
inhibited Candida krusei and Candida glabrata, known for intrinsic fluconazole
resistance. Importantly, none of the aqueous extracts produced inhibitory zones
against oral commensal bacteria, indicating selective antifungal activity without
disturbing the beneficial oral microbiota. Phytochemical screening revealed the
presence of alkaloids, glycosides, tannins, terpenoids, saponins, and flavonoids,
which may contribute synergistically to the observed anticandidal activity. These
findings highlight the significance of A. marmelos, L. inermis, and C. zeylanicum
as promising plant-based alternatives, making them promising candidates for developing
a safe, natural herbal mouthwash to manage oral candidiasis without
disrupting the oral microbial balance.
