Synthesis of α−mangostin-D-glucoside in supercritical carbon dioxide media.

α-Mangostin, the major xanthone constituent of
mangoteen fruit pericarp, has several important pharmaceutical
application but its bioavailability is restricted due to its
insolubility in water. Herein, we synthesized water soluble
α-mangostin-D-glucoside by glycosylation of α-mangostin
at hydroxyl group; using amyloglucosidase (3.2.1.3) catalyzed
reaction in supercritical carbon dioxide (SC-CO2) media.
Response surface methodology (RSM) based on a fivevariable
central composite rotatable design involving 32 experiments
was used to determine the effect of pressure (80–
160 bar), temperature (35–75 °C), enzyme concentration (15–
45 mg), buffer pH (4.0–8.0) and buffer volume (1.0–5.0 mL).
Experimental data fitted the second-order polynomial equation
as indicated by R2 value of 0.94. The optimal enzymatic
conversion within the experimental range of the variables
reached 20.3 % at a pressure of 120 bar, temperature of
55 °C, enzyme concentration of 30 mg, buffer volume of
3 mL and pH 6.0 which is well matched with the predictive
yield.