Anthocyanins, Phenolic Acids and Antioxidant Properties of Juçara Fruits (Euterpe edulis M.) Along the On-tree Ripening Process

Abstract

Juçara (Euterpe edulis M.) fruits are an interesting source of phenolic compounds, mainly anthocyanins, making them valuable to the food and pharmaceutical industries. Juçara fruits were harvested along the on-tree ripening process between March and June as practiced in Paraná state, Brazil and examined for their total anthocyanin content (TAC), total phenolic content (TPC), total phenolic acid (TPA) and total antioxidant capacity (TAA). Overall, TAC increased (91.52-236.19mg cyanidin-3-glucoside equivalent/100gdm) whereas TPC (81.69-49.09mg GAE/gdm) and TPA (44.27-30.95mg/100gdm) decreased during ripening of juçara fruits. Use of tandem mass spectrometry allowed the identification of cyanidin-3,5-diglucoside, peonidin-3-glucoside and peonidin-3-rutinoside for the first time in juçara fruits. The analysis of the phenolic acids by HPLC-MS/MS indicated the presence of gallic, protocatechuic, p-hydroxybenzoic, vanillic, chlorogenic, caffeic, syringic, p-coumaric, sinapinic and ferulic acids. The high antioxidant capacity using DPPH radical scavenging capacity (655.89-745.32μmol TE/gdm) and ORAC assays (1088.10-2071.55μmol TE/gdm) showed that juçara fruits have potential as a source of novel natural antioxidants for disease prevention and health promotion, and also as natural food additives for developing new functional food products.