Phytochemical, Antioxidant and Antibacterial Studies of Ethanolic and Methanolic Extracts of Aloe elegans Leaves gel

The study was aimed at investigating the phytochemicals, antioxidant and antibacterial activities of the ethanolic and methanolic extracts of Aloe elegans leaves gel. The phytochemical screening revealed the presence of phenols, flavonoids, anthraquinones, tannins, sapponins and terpenoids in both extracts. The antioxidant activities of both extracts were assayed using ferric reducing antioxidant power (FRAP), conjugated diene (CD) and peroxide value (PV) methods using sunflower oil (SFO) as the oxidizable substrate. The value for methanol and ethanol extracts of Aloe elegans leaves gel and the standard ascorbic acid in the ferric reducing power assay at 20 μg/mL were found to be 65.32 %, 62.89 %, 59.4 % respectively. The peroxide value after 12 days at room temperature for the Sunflower oil (SFO) was found to be 45 mmol/L while the value for the substrate containing methanol, ethanol extract and vitamin E were found to be 36, 38, 43 mmol/L respectively. The value of the absorption coefficients of conjugated dienes resulted from oxidations of the methanol and ethanol extracts and vitamin E were found to be 3.006, 3.387, 4.306 g-1cm-1mL respectively. In all the antioxidant assays used, the methanolic extract was found to inhibit oxidation of sunflower oil to a better extent than its ethanolic counterpart. Relative to vitamin E, both extracts exhibited better antioxidant efficacy. In the antibacterial assay, both the extracts showed potent bactericidal effects against Escherichia coli and Staphyloccus aureus, though to a lesser extent than the standard antibiotic Gentamicin.