Purple corn (Z ea mays L.) pericarp hydroalcoholic extracts obtained by conventional processes at atmospheric pressure and by processes at high pressure

Extracts of Peruvian purple corn pericarp ( Zea mays L.) were obtained: (1) via supercritical fluid extraction with CO 2 as solvent and EtOH-H2O (70:30, v/v) as co-solvent, (2) via pressurized liquid extraction (PLE) with EtOH-H 2 O (70:30, v/v) and, (3) via two conventional extraction processes, stirred vessel and Soxhlet. The extraction yields and extract compositions were compared to each other. The parameters measured were the point-to-point extraction yield, the global extraction yield and composition of extracts regarding contents of total phenolics, total flavonoids, total anthocyanins and specific anthocyanins such as cyanidin-3-glucoside, peonidin-3-glucoside and pelargonidin-3-glucoside. Antioxidant activity by DPPH and in vitro antiproliferative activity were also evaluated considering seven cancer cell lines. High yields and higher contents of phenolic compounds, accompanied by a high antioxidant activity at 50 °C, were obtained for supercritical extraction at 60 °C. Antioxidant activity showed good correlation with the content of phenolic compounds, but there was no antiproliferative activity.