Coconut Waste As a Potential Source for Cytotoxic and Antioxidant Compounds

Despite the reported cytotoxic activity of the endocarp of Cocos nucifera (Arecaceae), the active principles were never characterized. The total extract (T), methylene chloride (M) and ethyl acetate (E) fractions were investigated for selective cytotoxic activity towards prostate cancer cell line (PC3) compared to normal cells (WI38), T showed remarkable activity (IC50=10.89 ± 2.1 μg/ml), M and E showed comparable moderate activity. All showed significantly higher IC50 values towards WI38 with selectivity index (SI) values of >18.3, >11.8 and 6.6, respectively. The phytochemical investigation of M has led to isolation of coniferaldehyde (1), sinapaldehyde (2), p-hydroxy benzoic acid (3), protocatechuic acid (4), vanillic acid (5), protocatechuic aldehyde (6), balanophonin (7), guaiacylglycerol-β-coniferyl aldehyde ether (8), E-piceatannol (9), kompasinol A (10) and apigenin (11). The cytotoxic and antioxidant potential of the isolates was investigated. Compounds 1, 4, 7–9 and 11 showed selective cytotoxic activity against PC3. Compounds 6, 9 and 10 showed remarkable antioxidant activity. . These results added a medicinal value for the coconut endocarp, instead of being as a wasted resource; it could be renewable inexpensive source of potential leads for selective cytotoxic drugs.