BIOACTIVE COMPOUNDS AND ANTIOXIDANT ACTIVITY OF AN ETHANOLIC EXTRACT FROM JABUTICABA SEED FLOUR

Jabuticaba (Myrciaria/Plinia spp.) is a fruit native to the Brazilian Atlantic Forest and is widely produced in southeastern Brazil. Its seeds, which account for approximately 15% of the fruit, are relevant sources of phenolic compounds and natural antioxidants, as well as minerals and bioactive compounds, including anthocyanins, phenolic acids, and tannins. This study aimed to evaluate the contents of total phenolic compounds, total flavonoids, monomeric anthocyanins, and total antioxidant capacity of a jabuticaba seed flour extract (JSFE). Jabuticaba fruits were donated by VNFAGAN/Seu Pé de Jabuticaba, located in Casa Branca, São Paulo, Brazil. The fruits were sanitized with sodium hypochlorite (300 ppm) for 15 min and subsequently mechanically pulped. The seeds were dried in a forced-air circulation oven at 50 °C for 48 h, ground using a knife mill (30 mesh), and stored under freezing conditions – 20 °C. For extract preparation, 1 g of jabuticaba seed flour (JSF) was extracted with 10 mL of 60% ethanol (v/v) in three 30-min cycles using an ultrasonic bath. The extracts were then filtered through filter paper and stored in amber bottles until analysis. Total phenolic compounds (TPC) were quantified using the Folin–Ciocalteu method and expressed as milligrams of gallic acid equivalents per gram of dry flour extract (mg GAE/g DFE). Total flavonoid content (TFC) was determined and expressed as milligrams of quercetin equivalents per gram of dry flour extract (mg QE/g DFE). Monomeric anthocyanins were determined using the pH differential method and expressed as milligrams of cyanidin-3-glucoside equivalents per 100 g of dry flour extract (mg C3G/100 g DFE). Antioxidant capacity was evaluated using the ABTS^•+, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC) assays, with results expressed as micromoles of Trolox equivalents per gram of dry flour extract (μmol TE/g DFE). The JSFE showed a TPC of 51.92 ± 7.90 mg GAE/g DFE, a TFC of 2.38 ± 0.24 mg QE/g DFE, and a monomeric anthocyanin content of 7.10 ± 0.56 mg C3G/100 g DFE. Regarding antioxidant capacity, the JSFE exhibited values of 171,148.83 ± 30,720.90 μmol TE/g DFE for ABTS^•+, 7.94 ± 0.75 μmol TE/g DFE for FRAP, and 461.45 ± 45.15 μmol TE/g DFE for ORAC. Overall, the JSFE showed relevant levels of phenolic compounds and flavonoids, as well as antioxidant activity detected by the ABTS^•+, FRAP, and ORAC assays. These findings highlight the potential of jabuticaba seed flour extract as a source of bioactive compounds and support further investigation of its biological properties.

Acknowledgments:

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) - Finance Code 001; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (307314/2023-5; 404066/2025-9; 152541/2025-0) and FAPESP (2023/17076-1, 2022/09493-9).