Optimization of Supercritical Carbon Dioxide Extraction of Xanthones from Mangosteen Pericarp by Response Surface Methodology

Mangosteen fruit pericarp is one of the important
sources of bioactive compound xanthone. Supercritical
carbon dioxide (SC-CO2) extraction was employed to
extract xanthones from mangosteen fruit pericarp at three
different levels of pressure (200–300 bar), temperature (40–
60 °C) and solvent to material ratio (100–300 kg/kg). The
optimal conditions for the total xanthone yield and the
influence of parameters were determined by response
surface methodology (RSM) using Box–Behnken design.
In our study, the increase in total xanthone yield in SC-CO2
fluid extraction depends more on the solute’s vapor effect.
From response surface plots, pressure, temperature and
solvent to material ratio exhibited independent and interactive
effects on the extraction of xanthones. A regression
equation for predicting the total xanthone yield was derived
by statistical analysis, and a model with predictive ability of
0.99 was obtained. Maximum xanthone yield of 8.01% was
predicted by RSM at 60 °C, 300 bar and a solvent to
material ratio of 300 kg/kg while experimentally a yield of
7.56% was achieved. HPLC analysis was carried out for the
optimum conditions for the identification and quantification
of the xanthones. The antioxidant activities of the extracts
were investigated by ferric reducing antioxidant power
(FRAP) and the results showed that the extracts were
enriched with antioxidant compound.