Determination of Anthocyanins, Total Phenolic Content, and Antioxidant Activity in Andes Berry (Rubus glaucus Benth)

ABSTRACT: Anthocyanins, total phenolic content, ascorbic acid content, and the antioxidant activity were determined in extracts of Andes berry fruit ( Rubus glaucus Benth). Anthocyanis (ACNs) were isolated and characterized by means of high‐performance liquid chromatography (HPLC) with photodiode array detection and electro spray ionization/mass spectrometry (PDA‐ESI/MS/MS) analysis. The anthocyanin (ACN) content was 45 mg/100 g FW. The isolated anthocyanins were characterized as cyanidin 3‐sambubioside, cyanidin 3‐glucoside, cyanidin 3‐xylorutinoside, cyanidin 3‐rutinoside, pelargonidin 3‐glucoside, and pelargonidin 3‐rutinoside. The ascorbic acid content was 10.1 mg/100 g FW. The total phenolic content as determined by the Folin–Ciocalteau method was 294 mg GAE/100 g FW while the antioxidant activity as measured by ABTS · + radical scavenging capacity and ferric reducing antioxidant power (FRAP) was 2.01 and 4.50 mmol TE/100 g FW or 8.22 mmoles ferric iron reduced/100 g FW, respectively. The high phenolic content and antioxidant capacity of Andes berry suggest that this fruit could be a rich source of natural pigments, nutraceuticals, and natural antioxidants.