Determination of Phenolic Compounds’ Extraction Conditions from Pistacia palaestina Leaves at Two Different Stages of Maturity

Background: Phenolic compounds are distributed throughout the plant kingdom. Numerous investigations have proved that Pistacia species have secondary metabolites, and these contain different classes of bioactive phenolic compounds. Objective: The objective of the present work was to optimize the extraction conditions of phenolic compounds from Pistacia palaestina leaves cultivated in Syria and find out the effects of the solvent type, extraction time, and temperature on total phenolic content (TPC) and in vitro antioxidant activity% (AA%). Two different growth stages were studied. Methods: Antioxidant activity and total phenolic content values were estimated using 2,2’-diphenyl- 1-picrylhydrazyl and Folin-Ciocalteu methods, respectively. Results: The highest TPC and AA% were found in fresh leaves (14.32g/100g and 92.69%, respectively). The optimum extraction solvent for phenolic recovery and antioxidant capacity was acetone 40%. Changes both in temperature (25, 40, 60 and 80°C) and time (15, 30, 45 and 60 min) had no significant influence on TPC and AA% of Pistacia extracts. Conclusion: Phenolic compounds could be extracted in a short time at a low temperature and could be used as natural antioxidant agents.