Characterization of Antioxidant Compound from Syzygium polyanthum Leaves Fraction Using UHPLC-HRMS

The leaves of Syzygium polyanthum is widely used in Indonesia as a spice . It has been reported to have significant antioxidant activity . However, the reports on compound s responsible for the activity are  very scarce . The purpose of this research was to characterize the chemical profile of S. polyanthum fractions which showed the highest antioxidant activity . The dried leaves of S. polyanthum were fractionated using the different combination of non-polar to polar solvent, those are n -hexane, acetone, water.  Fourteen fractions were collected and analyzed for their DPPH antioxidant activity . T he chemical profile of selected fractions was characterized using UHPLC-HRMS to identify compounds that might associate with the antioxidant activity of S . polyanthum . The results showed that at the dose of 500 μg/ml, four fractions showed the highest antioxidant activity with the following order : F9 (acetone:water=80:20) , F10 (acetone:water=60:40), F1 (hexane 100%) and F3 (hexane:aceton=80:20). UHPLC-HRMS analysis successfully identified several  compounds in F9 and F10. Gallic acid, pyrogallol, and myricetin were  identified in F9. Aconitic acid was identified in F 10. All of the identified compounds were previously reported to have antioxidant activity