Title : Phytochemical, antioxidant and antibacterial activities of Vernonia amygdalina Del. leaf extract
Abstract:
Scientific standardization as well as possible therapeutic effects of some herbal preparations, alternatives against antibiotic resistant bacterial infections indicates a strong need for continuous effort to validate the use of plant materials as alternative therapy regimens with similar or higher antibiotic beneficial properties. The study was aimed to at evaluating the phytochemical, antioxidant, antibacterial activities of Vernonia amygdalina leaves.Phytochemical screening was achieved using standard qualitative phytochemical screening procedures. Antibacterial studies were carried out using agar well diffusing methods. The antioxidant activities of the methanol extract was determined by means of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Flavonoid, alkaloids, tannins, saponins, steroids, triterpenes, carbohydrate and phenols were detected in methanolic extract. The methanolic extract showed higher radical scavenging ability than ascorbic acid at the highest concentration of 1000 µg/mL. The IC50 values of the methanol extract of Vernonia amygdalina leaves against DPPH free radical were 20.625 µg/ml. The Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) of the Vernonia amygdalina leaf extract recorded respective values of 15.625 mg/ml and 31.25 mg/ml against Pseudomonas aeruginosa and Escherichia coli and 7.8125 mg/ml and 15.625 mg/ml against Staphylococcus aureus. The FTIR analysis showed the presence of alcohol, phenol,carboxylic acid, aldehyde and ketone functional group. This study has proven the effectiveness and efficacy of Vernonia amygdalina against the tested clinical isolates.
