During my frequent trips to south-east Asia, I always enjoy a very peculiar, tropical fruit – mangosteen. It is one of the most praised of tropical fruits, and certainly the most esteemed fruit in the family Guttifera. The fruit is round and about 1.5 -2″ in diameter with a very dark purple smooth skin. It is better to open it with a knife by cutting around the middle completely through the rind, and lifting off the top half, which leaves the snow-white, juicy, soft segments exposed in the colorful “cup”‚??the bottom half of the rind. The fruit is exquisitely luscious and delicious, and it is by far my most favorite taste of all.
The rind of partially ripe fruits yields a polyhydroxy-xanthone also called √?-mangostin; whereas, fully ripe fruits contains the xanthones and various derivatives. Xanthones are unique chemical compounds composed of a tricyclic aromatic system with a variety of phenolic, methoxy, and isoprene substituents, giving rise to numerous derivatives. They dissolve to varying degrees in solvents ranging from alcohol to hexane.
Scientist at Weber State University developed methods for extraction, identification and quantitation of xanthones and their derivatives: alpha-mangostin, 8-desoxygartanin, gartanin, beta-mangostin, 3-mangostin, and 9-hydroxycalabaxanthone. They found that the optimum solvent mixture of acetone/water (80:20) selectively and effectively extracts a wide variety of xanthones and subsequent [tag]HPLC[/tag] analysis using standard C 18 Reverse Phase column and a 30-min gradient of 65-90% methanol in 0.1% formic acid detects and separates numerous different xanthones with UV detection at 254 nm.