MINERAL COMPOSITION OF ACAI SAMPLES FROM AMAZONIAN REGION, BRAZIL

Acai fruit is responsible for a large proportion of the farm economy in the Amazon region. Pulps of two species, Euterpe precatoria and Euterpe oleraceae, have antioxidant and anti-inflammatory properties with bioactive metabolites such as anthocyanins and flavonoids, but little has been described about the mineral composition of these species. The aim of this study was to analyze the mineral content of two different species of acai fruit (Euterpe precatoria and Euterpe oleraceae) from the Amazônia biome, Brazil. Three samples of E. precatoria, two from Coari-AM and one from Anori-AM (PCo1, PCo2, PAn3, respectively) were compared to three samples of E. oleraceae being two from Coari-AM and one from Acará-PA (OCo1, OCo2, OAc3, respectively). Wave dispersion x-rays fluorescence (WDXRF) method was used to measure the content of Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Cu, Zn, and I of the samples, in triplicate. Kruskal-Wallis followed by Dunn’s multiple comparison test was performed using GraphPad Prism software, version 9.4.1 (San Diego, California, USA). Results have been expressed as the quantity (g) of each mineral in 100 g of sample, dry weight (m/m). Among the majoritarian minerals found in the E. precatoria samples are K (3.63-4.30%) and Al (3.63-4.30%), while in the E. oleraceae were K (3.62-5.61%) and Ca (1.13-2.81%). There were no differences between samples regarding the amount of Al, Si, P, S, Cl, K, Ca, Mn, and I. Differences in the content of Mg (p = 0.01), Fe (p = 0.02) and Cu (p = 0.04) were found between the E. precatoria and E. oleraceae samples (PCo1 x OCo1, PCo1 x OCo1, PCo2 x OCo2, respectively). We also noted differences between the same acai specie (E. oleraceae) in the content of Cl (OCo1 x OCo2, p = 0.01) and Zn (OAc3 x OCo2, p = 0.02). The mineral composition of fruits is linked to the mineral composition of the soil, consequently, the soil composition could be responsible for the differences observed in the samples. Regarding mineral composition, E. precatorea and E. oleraceae samples seem to differ in terms of Mg, Fe, and Cu content.