Ginseng And Ginsenosides
By Heidi Li, NOW Quality Control Dept.
Ginsengs have been used in various traditional medicinal therapies for thousands of years in China and North America. At present, it is also used as an ingredient for formulation of herbal supplements and functional foods. Ginseng is reported to have a wide range of therapeutic and pharmacological activities, which focus on immunological, anti-cancer, central nervous system, acceleration of metabolism, and anti-oxidant properties.
Asian ginseng (Panax ginseng C.A. Meyer), and American Ginseng (Panax quinquefolius L) are the two major species of ginseng. The primary active ingredients of ginseng are a group of 31 triterpene saponins, also known as ginsenosides. Ginsenosides can be classified into three groups on the basis of the chemical structure of their sapogenins: the panaxatriol group including Re, Rf, Rg1, Rg2, Rh1, the panaxadiol group including Rb1, Rb2, Rb3, Rc, Rd, Rg3, Rh2, Rs1, and the oleanolic acid group including Ro. However, six of them, Rg1, Re, Rb1, Rc, Rb2, and Rd, are the major ginsenosides accounting for over 90% of the total saponin concentration. It is observed that the ratio of individual ginsenosides may be an important factor in the pharmacological and therapeutic effects of ginseng extracts. For example, panaxatriol group has an effect on memory enhancing, whereas the panaxadiol group does not.
The typical source of ginsenosides is from the ginseng root, but current research has found that the ginseng leaf and ginseng berry is alternative sources of ginsenosides. The different total amounts, as well as the specific ginsenoside profile, vary depending on many variables. These variables include the species (i.e. American ginseng or Panax ginseng), growth environment (wild or cultivated), soil and fertility conditions, parts of the plant used, age of the plant, and extraction methods used.
To ensure the quality of our products and to determine the pharmacological and therapeutic effects of our products, it is important to develop the correct analytical method to quantify the total ginsenosides as well as to identify the individual ginsenoside levels present. There are different analytical methods reported for analyses of ginsenosides. The UV method can be used for determine of total ginsenoside but not for individual ginsenoside levels. Gas chromatography has some technique difficulties for separation of individual ginsenosides. Thus, at NOW Foods, we use the HPLC method, which is the most successful and widely accepted analytical procedure. Based on the HPLC method used for American Botanical Council's Ginseng Evaluation Program, our HPLC method is for identification and quantitative analysis of seven major ginsenoside Rg1, Re, Rf, Rb1, Re, Rb2, and Rd content in both American and Asian Ginseng products.