Antioxidant Activity of Polyphenolic Leaf Extract from Santolina chamaecyparissus L. (Asteraceae) and the Isolated Luteolin-7-O-Glucoside

Aim: The present study aimed to investigate the chemical constituents and antioxidant potential of Santolina chamaecyparissus polyphenolic extract (SCPE). Materials and Methods: The extract containing phenolic compounds, was extracted with ethyl acetate and luteolin-7-O-glucoside was separated and purified using flash chromatography on silica gel column. This isolated compound was identified according to its physicochemical properties and spectral data (UV, LC–TOF-MS, 1H NMR, 13C NMR and 2D NMR). In vitro antioxidant activity of the isolated compound and SCPE was investigated using DPPH•, ABTS+, reducing power, superoxide anion radical scavenging and β-carotene bleaching assays. Results: Results showed that SCPE and luteolin-7-O-glucoside exhibited significant antioxidant activity. The antioxidant activity of SCPE was comparable to that of luteolin-7-O-glucoside. Luteolin-7-O-glucoside was isolated for the first time from Santolina chamaecyparissus polyphenolic extract. Conclusion: Results of the present investigation clearly indicate that SCPE and isolated compound (luteolin-7-O-glucoside) have powerful antioxidant capacity against various antioxidant systems in vitro