02398nas a2200229 4500008004100000245014300041210007300184260001800257300001000275490000700285520163000292653001601922653001401938653001401952653002001966100002001986700002902006700002602035700001802061700003102079856005802110 2018 eng d00aIsolation of 5,7‑Dihydroxy, 6,8‑Dimethyl Flavanone from Syzygium aqueum with Its Antioxidant and Xanthine Oxidase Inhibitor Activities0 aIsolation of 57‑Dihydroxy 68‑Dimethyl Flavanone from Syzygium aq cFebruary 2018 a60-630 v103 a

Background: Syzygium aqueum Burm.f. Alston (water apple) belonging to Myrtaceae family was originated from tropical areas. It was traditionally used as a medicinal plant. Objective: The objective of the study was to isolate the active compound from the methanolic extract of S. aqueum leaves. Methods: Extraction was done using continuous extraction with methanol as a solvent. The extract was then fractionated using liquid–liquid extraction, vacuum liquid chromatography, and radial chromatography. Recrystallization was done for purification. The structure of the compound was determined by Ultraviolet‑Visible and (1D and 2D) nuclear magnetic resonance (NMR) spectrometer. Results: The isolate showed maximum wavelengths at 347 (band I) and 296 (band II) nm. After addition of NaOH and CH3COONa, the maximum wavelengths of band II moved to 340 and 339 nm, respectively. There was no change in wavelengths after addition CH3COONa/H3BO3 and AlCl3. The 1H‑NMR spectrum showed 16 protons, whereas 13C‑NMR spectrum showed 15 carbons. Based on those data, the isolate was determined as 5,7‑dihydroxy‑6,8‑dimethyl flavanone (demethoxymatteucinol). At a concentration of 100 and 50 µg/mL, it could inhibit 25.13% of xanthine oxidase (XO) activity and scavenge 11.87% of diphenyl‑picrylhydrazyl, respectively. Conclusion: Demethoxymatteucinol was isolated for the first time from S. aqueum and it had mild antioxidant and XO inhibitory activities.

10aAntioxidant10aFlavonoid10aMyrtaceae10aSyzygium aqueum1 aInsanu, Muhamad1 aRamadhania, Zelika, Mega1 aHalim, Evelyne, Nadia1 aHartati, Rika1 aWirasutisna, Komar, Ruslan uhttps://phcogres.com/article/2018/10/1/104103prpr5917