Bitterness reduction and enzymatic transformation of ginsenosides from korean red ginseng (panax ginseng) extract

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 (236.21mg/mL), uronic acid (9,039.40μg/mL), polyphenols (608.57μg/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 15,958.1μg/mL, respectively. The ginsenoside Rh ₂ was only found after PC-2 treatment of red ginseng. The Rb ₂ and Rc contents following PC-2-treatment of red ginseng were 999.91 and 2,543.76μg/mL, respectively. The contents of the ginsenosides Rb ₁ and Road decreased from 5,699.38 and 1,889.72μg/mL (in PC-0) to 3,176.43 and 1,597.12μg/mL (in PC-2), respectively, and that of Rg ₃ increased from 511.0μg/mL (in PC-0) to 2,346.5μg/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, Rb ₂ and Rc were transformed into Rg3 or Rh2 and Rb ₁ was transformed into Rg ₃ following the optidex and viscozyme treatment.