Separation and identification of phenolics and flavonoids from wild Pistacia palaestina extract and its antioxidant activity

An in-vitro evaluation of the antioxidant activities of wild Palestinian Pistacia palaestina extracts was done. In parallel, the total phenolic content (TPC) and the total flavonoids content (TFC) were measured. The antioxidant activities were determined spectrophotometrically by DPPH, FRAP, CUPRAC and the ABTS methods. The phenolic and flavonoid contents were separated and identified using LC-PDA-MS. The P. palaestina extract was found to contain many phenolic and flavonoids that enhance its reducing activity and free radical scavenging ability. Total phenolic content, and total flavonoids contents were found to be 66.5 ± 2.2 mg Gallic acid/g, and 20.3 ± 1.1 mg catechin/g, respectively. Antioxidant activity represented as FRAP, CUPRAC, DPPH and ABTS was found to be 23.5± 1.2 mmol Fe+2/g, 4562 ± 63 µmol Trolox/g, 344 ± 11 µmol/g, 53.1 ± 6.6 µmol/g, respectively. The aim of the study is therefore to employ different antioxidant tests to evaluate the antioxidant activities of crude ethanol leaf extracts of P. palaestina, and to determine its phenolic and flavonoids content. Key words: Pistacia palaestina, flavonoids, antioxidants, Liquid chromatography–mass spectrometry (LC-MS).