The effects of different extraction parameters, including temperature,pressure and dynamic time on the antioxidant activity of P.nigrum L. essential oil,have not been studied before. These factors can be collectively studied to validate the
optimal extraction conditions using response surface methodology(RSM). Accordingly,the main objective of this study was to establish the optimum SC-CO2 extraction conditions for P.nigrum L. essential oil with a high antioxidant activity using RSM.