Phytochemical Screening and Antifungal Activity of Extracts from Eucalyptus camaldulensis Leaves in Kogi State

Fungal infections of crops and humans represent a significant burden in tropical environments such as Kogi State, North Central Nigeria, where high humidity and temperature create optimal conditions for fungal proliferation. Eucalyptus camaldulensis, widely planted across the state as a windbreak and timber species, has a documented history of medicinal use in local communities. This study conducted phytochemical screening and evaluated the antifungal activity of sequential solvent extracts of Eucalyptus camaldulensis leaves collected from Lokoja. Leaves were extracted with hexane, chloroform, ethyl acetate, methanol, and water. Standard qualitative phytochemical tests were performed. Antifungal activity was assessed against Candida albicans, Aspergillus niger, Aspergillus flavus, and Fusarium solani by the agar well diffusion method, with minimum inhibitory concentrations determined by the broth microdilution assay. Phytochemical screening revealed tannins, flavonoids, terpenoids, and saponins in ethyl acetate and methanol extracts, with alkaloids present only in the methanol extract. The ethyl acetate extract showed the broadest antifungal spectrum, with inhibition zones of 18 to 24 mm against all tested fungi. Minimum inhibitory concentrations against Candida albicans were 6.25 mg/mL for the ethyl acetate extract. Aspergillus flavus was the most resistant organism. Hexane and aqueous extracts exhibited minimal activity. These results support the development of eucalyptus-based antifungal preparations and encourage bioassay-guided isolation of active constituents from this locally abundant and sustainable plant resource in North Central Nigeria.

Keywords: Eucalyptus camaldulensis, antifungal activity, phytochemistry, Kogi State, minimum inhibitory concentration