ABSTRACT
Background: Nigeria is plagued with a variety of socioeconomic problems mainly poverty, poor access to quality healthcare and poor hygienic conditions resulting in the myriad of fungal infections that are frequently encountered in clinical practice. Method: The antifungal activity of aqueous, methanolic, propanolic and benzyl alcohol extracts of Capsicum annuum fruits and seeds, Capsicum chinense fruits and seeds, Aframomum melegueta pods and seeds, Allium sativum bulbs, Allium cepa bulbs and Zingiber officinale rhizomes on Candida albicans (yeast), Aspergillus niger (mould) and Trichophyton rubrum (dermatophyte) were evaluated by the agar well diffusion method. The aqueous and alcoholic filtered plant extracts were obtained by maceration, and also methanolic extracts were also obtained by Soxhlet extraction. The results were obtained by measuring the inhibition zone diameter in millimeters and were presented by subtracting the activity of the control. Results: Aqueous and methanolic extracts of Allium sativum gave the highest inhibition of the growth of Candida albicans (22 mm), followed closely by its propanolic extract with inhibition zone diameter of 15 mm, and also, propanolic extracts of Aframomum melegueta and Allium cepa gave inhibition zone diameters of 12 mm each. Soxhlet methanolic extract of Allium sativum had the highest inhibition of the growth of Aspergillus niger with an inhibition zone diameter of 25 mm, followed closely by Zingiber officinale Soxhlet methanolic extract with an inhibition zone diameter of 22 mm, also, the propanolic extract of Allium sativum gave an inhibition zone diameter of 21 mm, whereas Soxhlet methanolic extracts of Aframomum melegueta and Allium cepa gave an inhibition zone diameter of 19 mm each. The highest activity against Trichophyton rubrum was obtained with the Soxhlet methanolic extract of Allium sativum (39 mm), followed closely by its propanolic extract with an inhibition zone diameter of 27 mm. An inhibition zone diameter of 22 mm was recorded with the benzyl alcohol extract of Allium cepa, 22 mm with the Soxhlet methanolic extract of Aframomum melegueta and 19mm with the aqueous extract of Capsicum chinense seeds. Conclusion: The in-vitro inhibitory effects of these spice extracts indicated that the test spices could serve as potential candidates for developing new systemic and topical antifungal drugs against the wide range of pathogenic fungal strains, and they could also serve as natural prophylaxis against the fungal infections.