Nutritional composition and bioactive compounds of the tucumã fruit (Astrocaryum huaimi Mart.)

The Brazilian Cerrado has a large variation of fruits with different nutritional and physicochemical properties that have not been studied. The purpose of this study was to analyze the antioxidant properties, quantify the fatty acids and minerals (calcium, iron, potassium and sodium) of the tucumã fruit (Astrocaryum huaimi Mart.) found in the Brazilian state of Minas Gerais. For all analyzes were used peel and pulp of the fruit. Total phenols, tannin, and antioxidant activity were analyzed using the Folin-Ciocalteu, Folin-Denis and the DPPH (1,1-diphenyl-2-picryl hydrazyl) stable free radical assay methods, respectively, in the extracts: aqueous, acetone, and ethanolic. The aqueous extraction was carried out using distilled water at a fruit:water ratio of 1:3 (m v-1). The ethanolic extraction was performed using 95% alcohol at a fruit:alcohol ratio of 1:3 (m v-1). The acetone extraction was performed using acetone at a fruit:acetone ratio of 1:3 (m v-1). For determining fatty acids from tucumã oil Gas-liquid chromatography Varian (model CP-3800) was used. The minerals were quantified using inductively coupled plasma optical emission spectrometry (Thermo Fisher Scientific, Cambridge, England) model iCAP 6300 Duo. The data was analyzed using the Statistical Package for the Social Sciences (SPSS) software, version 22.0 and reported as average ± standard deviation. The comparisons were done using analysis of variance (ANOVA), followed by Tukey post hoc analysis. The values were statistically significant when p<0.05. The present study indicated a significant difference (p<0.0001) in the concentration of bioactive compounds in the different extracts. The tannins in the acetone extract resulted in 90.77 ± 1.13 mg EAT.100g-1, greater than in the ethanolic (63.57 ± 1.52) and aqueous (31.10 ± 0.34) extracts. The phenolic compounds were best extracted with ethanol (101.78 ± 1.88 mg EAG.100g-1) when compared to acetone (87.80 ± 2.48) or aqueous (62.17 ± 0.96). Among the analyzed extracts, the aqueous presented the least antioxidant potential with a confidence interval (CI50) equal to 259.95 ± 0.75, followed by the ethanolic (138.49 ± 0.89) and acetone (115.76 ± 5.67). The nutritional composition of the tucumã oil presented 29.4% of saturated fatty acids, 12.56% of polyunsaturated fatty acids and 46.2% of unsaturated fatty acids, with emphasis on oleic acid. In relation to the mineral analysis were obtained: calcium (162.84±3.88 mg.100g-1), iron (5.15±0.59 mg.100g-1), potassium (1766.05±38.93 mg.100g-1) and sodium (14.87±0.21 mg.100g-1). In the analysis of bioactive compounds, the acetone extract followed by the ethanolic had the best antioxidant potential and more phenolic compounds and tannins. The quantification of the fatty acids in the fruit presented more unsaturated fatty acids. The iron and potassium content stood out among the analyzed minerals, allowing the tucumã to be classified as a source of these minerals. Based on the results, the inclusion of tucumã pulp in the diet can prevent chronic diseases, as well as nutritional deficiencies, thus promoting health benefits.