Phenolic compounds profile of açaí (Euterpe oleracea) seeds characterized by UPLC-MS

Abstract: Açaí (Euterpe oleracea) processing generates large amounts of solid waste, mainly seeds, which account for approximately 85% of the fruit mass and whose improper disposal causes environmental and sanitary impacts. Identifying bioactive compounds in this byproduct may add value to the agro-industrial chain. Phenolic compounds are associated with antioxidant activity and with the reduction of oxidative stress, obesity, and hyperglycemia, contributing to the prevention of chronic diseases. This study aimed to identify and quantify the phenolic compounds of dried and ground açaí seeds. The seeds were dried in a forced-air oven at 60 ºC and ground in a knife mill, and the ground material was fractionated in a sieve shaker, with the 0.5–0.7 mm fraction used in the experiments. Proximate composition of the raw material revealed 5.80 ± 0.04% moisture, 5.25 ± 0.05% proteins, 3.66 ± 0.89% lipids, 1.23 ± 0.0004% ash, and 84.06% carbohydrates (by difference). Phenolic compounds were extracted with methanol and water and quantified by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS) using 16 external standards. Results revealed a total quantified phenolic content of 1,943.74 µg/g of raw material. The chromatographic profile was dominated by flavan-3-ols and dimeric procyanidins, with catechin as the major compound (603.95 µg/g), followed by procyanidin B2 (578.07 µg/g), procyanidin B1 (572.28 µg/g), and epicatechin (167.23 µg/g), which together accounted for over 98% of the quantified phenolics. Phenolic acids were detected in lower concentrations, notably p-hydroxybenzoic acid (10.92 µg/g), protocatechuic acid (6.80 µg/g), and syringic acid (4.49 µg/g). Overall, the phenolic fraction of açaí seed is dominated by (epi)catechin units, present both as free monomers and as dimeric procyanidins B1 and B2. As flavan-3-ols and procyanidins are widely recognized for their antioxidant properties, açaí seed emerges as a promising raw material for functional ingredients and antioxidant applications. This study contributes to SDG 3 (Good Health and Well-Being) by identifying compounds with healthpromoting potential, and to SDG 12 (Responsible Consumption and Production) through the valorization of an agro-industrial waste.

CNPq (130023/2026-4)