A COMPARATIVE STUDY OF THE POTENTIAL ANTIOXIDANT ACTIVITIES OF GINSENOSIDES

Abstract

ABSTRACT Ginseng roots are believed to contain over 20 different types of ginsenosides. However, no reports exist on the antioxidant activity of ginsenosides according to their various structures. The present study involves a comparison of the various forms of ginsenosides, a series of derivatives originating from the attachment of different sugar moieties to triterpene dammarane, with respect to their intracellular reactive oxygen species scavenging activity. Among the ginsenosides, Rb2 and Rc showed the strongest antioxidant activity, followed by (in decreasing order) Rg2, Rh2, Rh1, Rf, Rg3, Rg1, Rb1, Re and Rd. Furthermore, the antioxidant activity ranks of the various forms of ginsenosides were influenced by the types of dammarane, as well as the number of sugar moieties, and substitutive groups. To the best of our knowledge, this is the first report evaluating the antioxidant properties of ginsenosides with the goal of determining their structure–activity relationship. PRACTICAL APPLICATIONS Ginseng (Panax ginseng C.A. Meyer), a member of the Araliaceae family, is traditionally considered as one of the most important medicinal plants with high ginsenoside content. Ginsenoside is a triterpenoid glycoside, which is known to have diverse physiological and pharmacological activities. However, the correlation of structure and antioxidant activity has never been studied thus far in ginsenosides. A relationship exists between the type and position of the sugar moieties in ginsenoside. From these results, ginsenosides Rb2 and Rc might be very useful for the development of functional food and raw materials of medicine for antioxidants preventing oxidative stress-related diseases. And structure and antioxidant relationship may be potential for evaluating the structure and function relationship of other ginsenosides in order to elucidate which part of ginsenoside is essential with regards to increasing antioxidant activity and the development of novel antioxidants to treat diseases associated with free radicals.