Phytochemical and Cytotoxicity Investigations of Salvadora Persica Bark Extracts

Background/Aim: Salvadora persica is an evergreen shrub or small tree to 6-7m. Fruits have a sweet, agreeable, aromatic, slightly pungent and peppery taste. It has many biological activities such as antipyretic, anti-inflammatory and antifungal activities. This study aims to evaluate cytotoxic effect of Salvadora persica, meswak, (Salvadoraceae) extracts and isolate main compounds from the most effective extract on different human cell lines. Materials and Methods: Extracts from meswak sticks and bark, aqueous alcoholic (crude), petroleum ether, chloroform and ethyl acetate extracts were tested for their cytotoxic activities on human hepatocellular carcinoma, breast, lung and colon carcinoma cell lines. Cell viability was assessed by the mitochondrial dependent reduction of yellow MTT (3-(4, 5dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) to purple formazan. In addition, two triterpenes were isolated from the petroleum ether extract, most active extract, partitioned from aqueous alcoholic crude extract using thin layer and column chromatographic technique. Elucidation of the chemical structure of two triterpenes was established based on their spectroscopic data (MS, HNMR, CNMR& IR). Results: The petroleum ether extract is the most potent evaluated extract. It presented IC50=43.6 μg/ml against human hepatocellular carcinoma cell line-HepG2, IC50= 44.3 μg/ml against human breast carcinoma cell line-MCF7, 19.87 μg/ml against lung carcinoma cell line-A549 and 10.2 μg/ml against colon carcinoma cell line-HCT116, however the other extracts showed weak activities. Ursolic was more effective than oleanolic acid against HepG2, MCF7 and HCT116 (IC50= 26.32, 18.73 & 20.4μg/mL, respectively) while oleanolic was potent against A549 (IC50= 19.5μg/mL). Conclusion: petroleum ether extract and ursolic acid showed cytotoxic activity against all tested human cell lines. Petroleum ether extract was superior against HCT116 and A549 while ursolic acid was efficient against HepG2 and MCF7.