Nutritional Bioactives in Tropical Fruit

Abstract

The nutritional benefits of tropical fruits are poorly understood. We assessed mango flavonoid and xanthone constituents (quercetin, mangiferin and its putative metabolite norathyriol) as well as whole extracts of mango peel and flesh on the proliferation of MCF‐7 breast cancer cells using an MTS assay. A significant decrease in cell proliferation was observed for the aqueous phase extracts from both peel and flesh. The compounds quercetin and norathyriol, also significantly inhibited MCF‐7 cell proliferation. We also assessed the effects of quercetin, mangiferin and norathyriol on human peroxisome proliferator‐activated receptors (PPARs), PPARα, PPARβ and PPARγ in Cos 7 cells. Norathyriol and quercetin dose‐dependently inhibited PPARs activated by their specific ligands. The IC50 value for quercetin was 59.6 μM for PPARα, 76.9 μM for PPARβ and 56.3 μM for PPARγ. For norathyriol, the IC50 value was 92.8 μM for PPARα, 102.4 μM for PPARβ and 153.5 μM for PPARγ. Mangiferin did not significantly inhibit PPAR transactivation (IC50 > 1 mM). Our results show that mangoes represent a potential source of bioactive compounds that have biological activity against the proliferation of cancer cells. Future studies will assess mangoes for other potential bioactive compounds and will assess other transcriptional pathways, such as the estrogen receptor pathway.