The mechanism of acid-catalyzed conversion of ginsenoside Rf and two new 25-hydroxylated ginsenosides

- Two new derivatives of ginsenosides Rg9 are identified from red ginseng.
- The special point of two compounds was hydroxylation from ginsenoside Rg9 isomers.
- The newly found compounds are unique type of conversion ginsenosides.
- This paper explains the value of ginsenoside Rf as a mark substance of red ginseng.