Phytochemicals, polyphenols content, in vitro antioxidant and antibacterial activities of Albizia coriaria Welw ex. Oliver flower

Abstract

Albizia coriaria Welw ex. Oliver (hereafter A. coriaria) is a revered medicinal tree whose organs are used by indigenous African societies for managing various ailments. Herein, we assessed the secondary metabolites, total polyphenolics, free radical scavenging and antimicrobial activities of A. coriaria flowers. The dry powdered sample was extracted serially with ethyl acetate, ethanol and distilled water. Results of classical phytochemical screening showed that saponins, phenols, alkaloids, flavonoids, tannins and terpenes were the dominant phytochemicals. The highest total polyphenolic content (10.37 ± 0.02 mg QE/g DW and 72.09 ± 0.09 mg GAE/g DW) and free radical scavenging potential (IC50 = 24.23 ± 0.04 mg/mL) were for the ethyl acetate extract. It also had a higher bacteriostatic activity than the ethanolic extract against Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli and Staphylococcus aureus with diameters of inhibition ranging from 7.00 ± 0.00 to 22.00 ± 1.73 mm. The aqueous extract showed no appreciable antibacterial effect on the tested microorganisms. This is the first report which support the use of floral extracts of this species in the management of ailments in African traditional