In vitro antifungal and antioxidant activity of Cassia singueana stem bark ethanolic extracts and its fractions obtained from Gashua Town, Nigeria

The increasing resistance of fungal pathogens to conventional antifungal drugs and the growing interest in plant-based therapeutics have intensified the search for alternative bioactive agents. This study investigates the in vitro antifungal and antioxidant properties of ethanolic extracts obtained from the stem bark of Cassia singueana, collected in Gashua Town, Yobe State, Nigeria. The stem bark was air-dried, pulverized, and extracted using ethanol, followed by fractionation into different solvent fractions based on polarity. The antifungal activity of the extract was evaluated against Candida albicans and Aspergillus niger, using agar well diffusion and microdilution. At the same time, its antioxidant potential was assessed through established methods for free-radical scavenging. The evaluation of the extract’s antioxidant activity showed that the ethanol extract (CSET) had the strongest ability to neutralize DPPH free radicals, with an IC₅₀ value of 0.37 µg/ml. The plant also demonstrated strong antifungal effects: the minimum inhibitory concentration (MIC) of the sample ranged from 1.25 to 2.5 mg/ml, while the minimum fungicidal concentration (MFC) fell between 2.5 and 5.0 mg/ml. These findings suggest that Cassia singueana stem bark possesses valuable pharmacological properties and may serve as a potential source of natural antifungal and antioxidant agents. Further studies are recommended to isolate and characterize the specific phytochemicals responsible for these activities.