| Abstract
| - This work studied extractions of gypenosides from Gynostemma pentaphyllum using batch and continuouspressurized fluids. Temperature was found to be a dominant factor in extracting gypenosides from this plantmaterial. Using low solid to solvent ratio (50 g/L) was evidenced to avoid a rate limitation on batch pressurizedwater extraction of gypenosides. Within 3 h of continuous pressurized water extraction at 1.48 MPa, 373 K,10 mL/min, a high solid to solvent ratio (200 g/L) resulted in 106.7 mg/g gypenosides. Our experimentalresults showed that 100% recovery of gypenosides, i.e., 164 mg/g, was obtained following pressurized 80%ethanol extraction at the same operation condition. Purification of the extract using Amberlite XAD7-HPcolumn chromatography indicated that the purity of gypenosides increased from 24% to 83% by weight. Inthe bioassay aspect, the effect of concentrations of gypenosides in the extracts on the growth inhibition oftwo cancer cells was examined.
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