Effects of high pressure extraction on the extraction yield, total phenolic content and antioxidant activity of longan fruit pericarp

High pressure extraction (HIRE) was carried out to extract phenolic compounds from longan fruit pericarp. The influence of different solvents, solvent concentration (25-100%, v/v). solid to liquid ratio (1:25-1:100, w/v) were individually determined using these optimum extraction conditions. HPE was carried out at various pressures (200-500 MPa), durations (2.5-30 min) and temperatures (30-70 degrees C). The extraction yield, total phenolic contents and scavenging activities of superoxide anion radical and 1.1-dipheny 1-2-picrylhydrazyl (DPPH) radical of HPE extract were examined and then compared with those of the conventional extraction (CE). The application of HIRE obtained a higher extraction yield and required a less extraction time when compared to CE. Furthermore. the total phenolic contents and the antioxidant activities of HPE extract were higher than CE extract. This study indicated that this new technology can benefit the food and pharmaceutical industries. industrial relevance: This study focused on the evaluations of the extraction yield, total phenolic content and antioxidant activity of longan fruit pericarp by high pressure treatment. The high pressure extraction technology provided a better way of utilizing longan fruit pericarp as a readily accessible source of natural antioxidants in food and pharmaceutical industries. (C) 2008 Elsevier Ltd. All rights reserved.