Synergistic Antifungal Analysis of Carica papaya Leaf and Solanum melongena Peel Ethanolic Extracts Against Candida albicans

Abstract

Infectious diseases are responsible for most mortalities and morbidities globally. They are estimated to cause 17 million deaths annually.   Candida albicans is a microflora found in mucous membranes of the gastrointestinal tract and vaginal orifice. Though a  commensal organism, it can cause either oropharyngeal or vaginal candidiasis in immunocompromised states. It thus, is a common opportunistic infection especially in patients living with HIV/AIDS. Management of candidiasis requires use of antifungal agents but some  are costly or drugresistant. Therefore, there is need for exploration of novel and affordable treatment modalities. Medicinal plants  offer alternative therapeutic modalities. Against this backdrop, we sought to evaluate synergistic antifungal activity of ethanolic extract of  Carica papaya leaves and Solanum melongena fruit peel against Candida albicans. Ethical approval was sought from School of  pharmacy, Kabarak University Research Ethics Committee (KUREC) and National commission for science, technology, and innovation  (NACOSTI). Experimental research design was employed. Green leaves of Carica papaya were obtained from the school’s herbarium while  the eggplant fruit was purchased from Nakuru town market. The sample plants were dried and powdered. Phytochemical analysis  was carried out and antifungal activity evaluated via disk diffusion method. Phytochemical studies showed presence of tannins, alkaloids  and flavonoids in both plants. Anthraquinone glycosides were absent in both samples. Carica papaya and Solanum melongena ethanolic  extracts respectively showed activity against Candida albicans at different concentrations with zones of inhibition of 8.34mm and 7.98mm,  respectively, at the highest concentrations. S. melongena extracts showed a lower zone of inhibition against Candida albicans compared to  C. papaya extracts. Combined ethanolic extracts of Solanum melongena and Carica papaya showed higher activity at all concentrations  than individual extracts, implying synergism between the two plant extracts. The difference in zones of inhibition was significant at  different concentrations(P<0.05). The study findings have demonstrated that Carica papaya and Solanum melongena extracts have  remarkable antifungal activity against Candida albicans. This makes them potential efficacious antifungal agents against Candida albicans.