Hydroalcoholic Myrciaria dubia (camu-camu) seed extracts prevent chromosome damage and act as antioxidant and cytotoxic agents

The camu-camu seeds, which comprehend about 20% of the fruit weight, is discarded without taking benefit of their chemical components and potential application by the industry. In the current study, we characterized the phenolic composition, the in vitro chemical antioxidant effects, cytotoxic activity, and the inhibition of induced-cisplatin chromosomal aberrations of five camu-camu seed extracts obtained with different proportions of water (H₂O) and ethyl alcohol (EtOH). The 50% H₂O + 50% EtOH was the most promising extract because it presented higher total phenolic content (4802 mg GAE/100 g), antioxidant capacity (DPPH = 3694 mg AAE/100 g; FRAP = 6604 mg AAE/100 g; FCRC = 4918 mg GAE/100 g) and inhibited the cell growth of four cancer cell lines (GI₅₀ = 7.49 μg GAE/mL A549; 13.3 μg GAE/mL Caco-2; 15.57 μg GAE/mL HepG2 and 14.89 μg GAE/mL HCT8) without cytotoxic effects against normal cells (GI₅₀ IMR90 > 43.2 μg GAE/mL). The cytotoxic effects presented high correlation with the (−)-epicatechin and methylvescalagin contents, while gallic and 2,5-dihydroxybenzoic acids were associated with cytoprotective effects of HCT8 cancer cell line. The 50% H₂O + 50% EtOH extract also presented protective effect by decreasing 37% of the induced-cisplatin chromosomal breaks index, suggesting its antimutagenic potential, which may be associated to its antioxidant and cytotoxic activities.