BITTERNESS REDUCTION AND ENZYMATIC TRANSFORMATION OF GINSENOSIDES FROM KOREAN RED GINSENG (PANAX GINSENG) EXTRACT

Abstract

ABSTRACT In the paper, we studied the bitterness reduction and the changes in ginsenoside contents of ginseng extract by using commercial amylases and viscozyme, PC-0 (non-enzymatic treatment), PC-1 (spezyme prime treatment) and PC-2 (spezyme prime, optidex and viscozyme treatment). The PC-2 treatment resulted in high levels of total sugar (236.21 mg/mL), uronic acid (9,039.40 µg/mL), polyphenols (608.57 µg/mL) and solid contents (15.66%). Total ginsenosides contents following PC-2, PC-1 and PC-0 treatments of red ginseng were 31,850.6, 21,075.7 and 15,958.1 µg/mL, respectively. The ginsenoside Rh2 was only found after PC-2 treatment of red ginseng. The Rb2 and Rc contents following PC-2-treatment of red ginseng were 999.91 and 2,543.76 µg/mL, respectively. The contents of the ginsenosides Rb1 and Road decreased from 5,699.38 and 1,889.72 µg/mL (in PC-0) to 3,176.43 and 1,597.12 µg/mL (in PC-2), respectively, and that of Rg3 increased from 511.0 µg/mL (in PC-0) to 2,346.5 µg/mL (in PC-2). The bitterness value of PC-2-treated red ginseng decreased from 5.80 (PC-0) to 3.40 (PC-2). Optidex and viscozyme treatment increased total sugar, uronic acid, polyphenol and solid contents and reduced the bitterness of red ginseng extract. In particular, Rb2 and Rc were transformed into Rg3 or Rh2 and Rb1 was transformed into Rg3 following the optidex and viscozyme treatment. PRACTICAL APPLICATION Korean ginseng is recognized worldwide as a natural healthy food along with the global trend of preference for natural products. Ginsenosides are abundant in ginseng, especially ginsenoside metabolites, such as ginsenoside Rg3, Rg5, Rk1, CK, Rh1 and Rg2; the metabolites are attracting more attentions for their biological properties and health benefits. However, ginseng has an unfamiliar, bitter/sweet/earthy flavor, quite unlike most foods consumed in the west. We have also used enzymes (spezyme, optidex and viscozyme) for ginseng extraction and to reduce the bitterness and to change ginsenosides glycosides to ginsenosides metabolites.