Since two decades, subcritical water extraction (SWE) is well known as green technology for separation and extraction of plant materials. SWE can be applied for extraction of bioactive compounds. In this study, the subcritical water extraction of anthocyanins and total phenolic contents of barberry fruit (berberis vulgaris) was optimized using response surface methodology (RSM). A quadratic model was applied to predict the behavior of samples. Central composite design was employed using 13 treatment and 5 repeat in central points. The independent variables factors were temperature (110-170ºC) and time (10-50 minutes) for evaluation of anthocyanins and total phenolic contents as well as antioxidant activities of extracted barberry. Effects of extraction temperature and time were found to be significant on all responses. Optimal SWE conditions were identified as 157.50 °C temperature and 29.64 minutes for maximum total anthocyanins (9.84mg/mL), total phenolic contents (568.75 mg GAE/100 mL), and antioxidant activities (91.15%). Experimental values for response variables at these optimal conditions match well with the predicted values. Barberry extracts obtained by SWE showed more than 91% DPPH radical scavenging activities. This methodology could be applied in the extraction of bioactive compounds in the natural product industry.

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