Iran is among the main exporters of pistachio -Pistacia vera L.-. Thus, evaluation of phytochemical properties of this product is of crucial importance. In this study, effects of three types of solvents namely, polar protic solvents -i.e. ultrapure water, methanol and ethanol-, polar aprotic solvents -i.e. acetone and ethyl acetate- and a non-polar solvent -i.e. hexane-, on total phenolic compounds, total flavonoids, and total proanthocyanidins extractability as well as antioxidant activity -as evaluated by 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assay- of P. vera var. Sarakhs hull and kernel, were investigated. High extraction yields were observed following utilization of less polar solvents -43.14 and 34.19% for hull and kernel, respectively-. There were significant differences among solvents in terms of the amount of antioxidant compounds extracted. Ethanolic hull and kernel extract showed the maximum amounts of total phenols -113.21 and 169.53 mg of gallic acid equivalent per g of dried plant, respectively-, total flavonoids -87.03 and 139.47 mg of quercetin equivalent per g of dried plant, respectively- and total proanthocyanidins -110.60 and 150.32 mg of catechin equivalents per g of dried plant, respectively- followed by methanol > ultrapure water > ethyl acetate > hexane. Assessment of antioxidant activity showed that the ethanol extract of hull and kernel had the least IC50 -3.04 and 6.8 µg/ml, respectively- and the greatest value when assessed by FRAP -8.80 and 5.59 mmol/g, respectively-. The results suggested that P. vera var. Sarakhs hull and kernel extract can be regarded as a promising alternative for synthetic antioxidants.

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