In Vitro Antioxidant Activity and Cytotoxic Effect of Ethanol Extract of Vernonia elaeagnifolia Leaves against Breast Cancer Cell Lines

Vernonia elaeagnifolia is an evergreen creeping plant belonging to the sunflower family. It has been investigated for various medicinal properties, but there is limited information on its antioxidant and anticancer properties. This study therefore aims to examine the antioxidant and anticancer potentials of the ethanol extract of Vernonia elaeagnifolia leaves (VEE). VEE was obtained by maceration in 96% ethanol. Preliminary phytochemical screening was done according to standard method. Antioxidant activity of VEE was assessed using the 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS.+) radical scavenging assay. Cytotoxic effect against 4T1 and MCF7 breast cancer cells, as well as Vero non-cancerous cells was examined by the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Phytochemical screening of VEE reveals the presence of alkaloids, flavonoids, saponins, phenolics, and tannins. VEE exhibited modest antioxidant activity with IC50 of 147.28 μg/mL, compared to ascorbic acid which had an IC50 of 5.43 μg/mL. VEE possessed moderate cytotoxic effect against 4T1, and MCF7, and a mild cytotoxic effect against Vero cells with IC50 of 165.50, 185.68, and 299.66 μg/mL, respectively. VEE was less potent than Doxorubicin which exhibited IC50 values of 0.44, 2.09, and 4.51 μg/mL, against 4T1, MCF7, and Vero cells, respectively. The selectivity index of VEE was 1.6 - 1.8, indicating limited selectivity for cancer cells. The findings from this study have shown the potentials of Vernonia elaeagnifolia leaves as an antioxidant and a mild cytotoxic agent against breast cancer cells.