Investigation on antioxidant activity of pistachio (Pistacia vera L.) skin extraction

Plants contain phenolic compounds ranging from simple molecules such as phenolic acids to highly polymerized molecules such as tannins. Phenols and polyphenols in plant tissues have gained increasing scientific interest because of their potential beneficial effects on human health. Among which, the nut and skin of pistachio are known as a rich source of phenolic compounds with antioxidant, anti-inflammatory and antimicrobial properties. The aim of this study was to investigated feasibility for industrial production of phenolic compounds with antioxidant activity because of mass pistachio skin production in Iran .
The extraction experiments on two species of pistachio, namely Kalleghuchi (P. vera cv. Kallehghuchi) and Ohadi (P.vera cv . Ohadi) were carried out by using two methods, i.e. maceration and ultrasonic extraction and four solvents (acetone 70% ,ethanol 50% , methanol 50% and water). The antioxidant property of the extracts were then evaluated through DPPH and FRAP methods. experiment results showed that the highest and lowest amounts of the antioxidant property in DPPH assay method have the values respectively , IC50 0.057µg/ml and 0.099µg/ml related to extract taken from Ohadi and Kallehghuchi in water solvent with maceration method. Whereas, in FRAP assay method resulted in 5.59 mM and 2.57 mM as the highest and lowest antioxidant activity respectively related to the extract taken from Ohadi in ethanol solvent with maceration and ultrasonic methods.