Cytotoxic components of Pereskia bleo (Kunth) DC. (Cactaceae) leaves

Abstract

Dihydroactinidiolide (1) and a mixture of sterols [campesterol (2), stigmasterol (3) and β-sitosterol (4)], together with the previously isolated individual compounds βsitosterol (4), 2,4-di-tert-butylphenol (5), a-tocopherol (6), phytol (7) were isolated from the active ethyl acetate fraction of Pereskia bleo (Kunth) DC. (Cactaceae) leaves. Cytotoxic activities of the above mentioned compounds against five human carcinoma cell lines, namely the human nasopharyngeal epidermoid carcinoma cell line (KB), human cervical carcinoma cell line (CasKi), human colon carcinoma cell line (HCT 116), human hormone-dependent breast carcinoma cell line (MCF7) and human lung carcinoma cell line (A549); and non-cancer human fibroblast cell line (MRC-5) were investigated. Compound 5 possessed very remarkable cytotoxic activity against KB cells, with an IC50 value of 0.81μg/mL. This is the first report on the cytotoxic activities of the compounds isolated from Pereskia bleo.