Phytochemical Characterization and Optimization of the Antioxidant Activity of Jabuticaba Seed Extract (Myrciaria cauliflora) by Rotational Central Composite Design

The jabuticaba (Myrciaria cauliflora Berg) is a Brazilian fruit, native to the Atlantic Forest. Its composition has high nutritional value, phenolic compounds and antioxidant capacity. With interest in using sources rich in bioactive compounds, the seed has become a viable alternative for industries.Optimizing hydroalcoholic extraction could offer industries economic and sustainability potential, given the low toxicity of ethanol. The aim of this work was to optimize the extraction of jaboticaba seeds and study their antioxidant potential and phenolic composition.Optimization was carried out using a central composite rotational design (CCRD) with 11 trials, the variables being ethanol concentration (x1) and extraction time (x2), in relation to spectrophotometric analyses of total phenolic compounds (mg AGE.100 g-1), total flavonoids (mg CE.100 g-1), condensed tannins (mg CE.100 g-1), monomeric anthocyanins (mg C3G. g-1) and antioxidant capacity using the FRAP (µM SF. g-1), ABTS (µmol TE.100 g-1) and ORAC (µmol TE.100 g-1) methods. The centesimal composition of the fresh jaboticaba seeds was analyzed (g.100 g-1), as well as the bioactive compounds profile by Ultra-High Performance Liquid Chromatography-Q Exactive Plus Orbitrap Mass Spectrometer (UPLCQE-MS/MS). The centesimal composition showed high levels of protein (11.1 ± 3.19 g.100 g-1) and fiber (7.2 ± 0.50 g.100 g-1). 42 compounds were identified by UPLCQE-MS/MS analysis, 4 of which were anthocyanins, 2 tannins and 3 flavonoids. Optimization showed an influence of ethanol concentration on the results, with higher levels of phenolic compounds, flavonoids, monomeric anthocyanins and antioxidant capacity at concentrations of up to 50%, while for condensed tannins the concentration of 78.37% ethanol showed the best results. The time variable influence was less significant, except for the 52.73 minute extraction showing the highest levels of condensed tannins. The results indicate that the optimized extract of jaboticaba seeds using ethanol could be an alternative for application by the food and pharmaceutical industries.