Cytotoxic Activity of Hexane Extracts of Psidium guajava L (Myrtaceae) and Cassia alata L (Caesalpineaceae) in Kasumi-1 and OV2008 Cancer Cell Lines

Purpose: The cytotoxic effects of hexane extracts of Cassia alata and Psidium guajava leaves were evaluated in OV2008 ovarian and Kasumi-1 leukemia cancer cell lines, respectively. Methods: The cancer cells were exposed to various concentrations of either C. alata (100 – 180 μg/ml) or P. guajava (100 – 500 μg/ml) leaf extract for 24 h. Following treatment, the cells were evaluated using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to determine the cytotoxic effect of the extracts. C. alata extract was also analyzed using high performance liquid chromatography (HPLC). Results: C. alata and P. guajava extracts produced significant (p < 0.05) cytotoxicity in OV2008 and Kasumi-1 cell lines, respectively. The IC50 values were 160 μg/ml for C. alata and 200 μg/ml for P guajava. Further, the cytotoxicity exhibited by C. alata might be attributable to the flavonoid, kaempferol, which was identified as a constituent of the extract. Conclusion: The results suggest that further chemical analysis and mechanistic investigations should be conducted on P. guajava and C. alata extracts to validate their potential uses for anticancer therapy.