A new antioxidant xanthone from the pericarp of Garcinia mangostana Linn.

The air-dried fruit hulls of Garcinia mangostana Linn. were extracted with 85% ethanol. Furthermore, a new xanthone, 1,3,6-trihydroxy-2,5-bis(3-methylbut-2-enyl)-6',6'-dimethyl-4',5'-dihydropyrano[2',3':7,8]xanthone, along with five known xanthones related to their antioxidant activity was purified by silica gel column chromatography and then identified using spectroscopic methods (1D and 2D NMR, MS). The antioxidant activities were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capability. An activity-guided isolation and purification process were used to identify the components, showing the strong DPPH radical-scavenging activity of G. mangostana.