Correlation Between Phytochemicals Content, Antioxidant and Antimicrobial Activities of the Leaf, Seed, Bark, and Root Extracts of Parkia biglobosa

Abstract The correlation between phytochemical content, antioxidant activity, and antimicrobial properties of the leaf, seed, stem, and root extracts of Parkia biglobosa (African locust bean) was investigated. Qualitative and quantitative phytochemical analyses were conducted using standard methods, while antioxidant and antimicrobial activities were assessed using the DPPH radical scavenging assay and agar diffusion method, respectively. Phytochemical screening revealed the presence of alkaloids, flavonoids, tannins, saponins, glycosides, terpenoids, steroids, proteins, and phenolic compounds, with higher levels of phenolics, flavonoids, tannins, saponins, and alkaloids observed in the bark extract. All extracts exhibited dose-dependent antioxidant activity, with the bark showing the highest scavenging potential. The extracts also demonstrated notable antibacterial activity against Staphylococcus aureus and Salmonella typhi, and antifungal activity against Candida albicans and Aspergillus niger, particularly at higher concentrations. Zones of inhibition ranged from 1.0 to 13.0 mm. A strong positive correlation was observed between phytochemical content, antioxidant activity, and antimicrobial effects. These findings support the ethnomedicinal use of Parkia biglobosa and highlight its potential as a source of natural antioxidant and antimicrobial agents.