Determination of Carotenoids, Total Phenolic Content, and Antioxidant Activity of Araza (Eugenia stipitata McVaugh), an Amazonian Fruit

The fruit of Araza (Eugenia stipitata McVaugh) native to the Colombian Amazon is considered a potentially economically valuable fruit for the Andean economy due to its novel and unique taste. The fruit has an intense yellow color, but its chemical composition and properties have not been well studied. Here we report the identification and quantitation of carotenoids in the ripe fruit using high performance liquid chromatography (HPLC) with photodiode array detector (PDA) and atmospheric pressure chemical ionization (APcI) mass spectrometry (MS/MS). The qualitative carotenoid profile of the fruit according to maturity stage was also observed. Furthermore, antioxidant activity of the peel and pulp were assessed using the ferric reducing ability of plasma (FRAP), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods, in addition to chemical indexes and total phenolic content. Multiple carotenoids were identified in the peel and pulp including four xanthophylls (free and esterified as their mono and diesters) and two carotenes. One of the xanthophylls was tentatively identified as zeinoxanthin, while the others were identified as lutein, zeaxanthin, and beta-cryptoxanthin. Carotenes included alpha-carotene and beta-carotene. The total carotenoid content was significantly higher in the peel (2484 +/- 421 mu g/100 g FW) than in the pulp (806 +/- 348 mu g/100 g FW) with lutein, beta-cryptoxanthin, and zeinoxanthin as the major carotenoid components. The unique carotenoid composition of this fruit can differentiate it from other carotenoid-rich fruits and perhaps be useful in authentication procedures. Overall, results from this study suggest that Colombian Arazi may be a good edible source of carotenoids important in retinal health as well as carotenoids with provitamin A activity. Therefore, Arazi fruit can be used as a nutraceutical ingredient and in production of functional foods in the Colombian diet.