Assessment of antioxidant and antiproliferative activities and the identification of phenolic compounds of exotic Brazilian fruits

Phenolics including flavonoids are suggested to be the major bioactive compounds contributing to the health benefits of fruits and vegetables. The objective of the study was to determine the total phenolic and flavonoid contents, oxygen radical absorbance capacity (ORAC), peroxyl radical scavenging capacity (PSC), cellular antioxidant activity (CAA) and antiproliferative properties of selected cerrado fruits named gabiroba (Campomanesia cambessedeana Berg), murici (Byrsonoma verbascifolia Rich) and guapeva (Pouteria guardneriana Radlk). Gabiroba fruit showed the highest amount of total phenolics (851.0 +/- 40.7 mg/100 g fruit) and the highest antioxidant activity for both the performed assays (ORAC 8027.5 +/- 378.6 gmol TE/100 g fruit and PSC 2342.5 +/- 48.1 mu mol AAE/100 g fruit). Gabiroba fruit and the pulp of guapeva had the highest antiproliferative capacity with the lowest EC50 40.7 +/- 4.8 mg/mL and 37.9 +/-2.2 mg/mL, respectively. The results for the analyzed fruits for CAA were not significantly different from each other (p < 0.05) (murici 41.3 +/- 17.8; gabiroba 33.9 +/- 18.8 and the pulp of guapeva 23.3 +/- 4.2 mu mol quercetin/100 g fruit). More than 30 phenolic compounds in the pulp of guapeva, gabiroba and murici extracts were identified in the present study using ESI-TOF-MS. These results characterized for the first time the functional activity of selected Brazilian fruits and demonstrated the importance of these fruits from cerrado biome. (C) 2013 Elsevier Ltd. All rights reserved.