Compound K producing from the enzymatic conversion of gypenoside by naringinase

Compound K is a type of protopanaxadiol-type ginsenosides (PPDs) that has strong bioactivities due to fewer glycosyls. However, compound K is not present in raw and unprocessed ginseng. Some PPDs have the same structure with gypenosides, and could be obtained from Gynostemma pentaphyllum. The enzymolysis of PPD-type gypenosides of G. pentaphyllum by naringinase has been reported for the first time in this research. In addition, isolation and identification of enzymolysis end product, and the optimization of enzymolysis parameters were investigated. The results showed that compound K was produced from the enzymolysis of PPD-type gypenosides by naringinase, and could be isolated and purificated by HP-20 macroporous resin and C-18 column chromatography. The optimum enzymolysis conditions determined by the response surface methodology (RSM) are pH 4.1, 50 °C, and 71 h, with a yield of 65.44 ± 4.52% for compound K. These results demonstrated that enzymolysis could be a promising method for producing compound K from the biotransformation of PPD-type gypenosides of G. pentaphyllum. •Protopanaxadiol-type gypenosides were isolated from total gypenosides.•Compound K was prepared from protopanaxadiol-type gypenosides by naringinase.•The optimum enzymolysis conditions were pH 4.1, 50 °C, and 71 h.•Enzymatic conversion was an easier and cheaper way to obtain compound K.