Abstract:
The present study aimed at investigating the phytochemical, antioxidant and antibacterial activities
of the ethanolic and methanoli 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 antioxidant activities of the extracts were
compared with those of the familiar compound vitamin E. The antibacterial activities of the extracts
were likewise evaluated using agar well diffusion method using the known antibiotic Gentamicin as
a reference. 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 at the end of the storage period of 12 days at room
temperature for the control 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 formed as a result of
oxidations of the methanol and ethanol extracts and vitamin E were found to be 3.006, 3.387, 4.306
g -1 cm -1 mL respectively.
In all the antioxidant assays used in this work, the methanolic extract was found to inhibit oxidation
of sunflower oil to a better extent than its ethanolic counterpart. Relative to vitamin E, both the
methanolic and ethanolic 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.