Phytochemical investigation of the ethyl acetate extract of the roots of Aloe megalacantha led to the isolation of four new natural products-1,8-dimethoxynepodinol (1), aloesaponarin III (2), 10-O-methylchrysalodin (3) and methyl-26-O-feruloyl-oxyhexacosanate (4)-along with ten known compounds. All purified metabolites were characterized by NMR, mass spectrometric analyses and comparison with literature data. The isolates were evaluated for their cytotoxic activity against a human cervix carcinoma cell line KB-3-1 and some of them exhibited good activity, with aloesaponarin II (IC50 = 0.98 µM) being the most active compound.
Keywords: Aloe megalacantha; Asphodelaceae; anthraquinone; cytotoxicity; quinone; roots.