Korean ginseng: Background

Historical Note

Gin refers to man and seng to essence in Chinese, whereas Panaxis derived from the Greek word pan (all) and akos (cure), referring to its use as a cure-all. Ginseng is a perennial herb native to Korea and China and has been used as a herbal remedy in eastern Asia for thousands of years. It is considered to be the most potent Qi or energy tonic in TCM. Modern indications include low vitality, poor immunity, cancer, cardiovascular disease and enhancement of physical performance and sexual function. However, a recent systematic review of RCT found that the efficacy of ginseng root extract could not be established beyond doubt for any of these indications.

Common Name

Korean ginseng

Other Names

Ren shen (Mandarin), red ginseng, white ginseng

Botanical Name / Family

Panax ginseng C.A. Meyer (family Araliaceae)

It should be differentiated from Panax aquifolium (American ginseng), Panax notoginseng (Tien chi, pseudoginseng), Eleutherococcus senticosis (Siberian ginseng) and other ginsengs.

Plant Part Used

Main and lateral roots. The smaller root hairs are considered an inferior source. There are two types of preparations produced from ginseng: white ginseng, which is prepared by drying the raw herb, and red ginseng, prepared by steaming before drying. Cultivated ginseng differs from wild ginseng and plants from different countries or regions may also differ greatly. Processing of the crude herb to produce red ginseng appears to increase its potency. Steaming has been shown to alter the composition of the ginsenosides; for example, steaming produces the active 20(S)-ginsenoside-Rg(3) (Matsuda et al 2003) and makes certain ginsenosides more cytoxotic.

The British Herbal Pharmacopoeia (1983) stipulates that ginseng should contain not less than 20% solids (70% ethanol). The German Pharmacopoeia requires not less than 1.5% total ginsenosides calculated as ginsenoside Rg 1.

Chewing gums containing ginseng saponins have also been developed and demonstrate therapeutic effects in some trials.

Chemical Components

The most characteristic compounds in the ginseng roots are the ginsenosides, and most biological effects have been ascribed to these compounds. The ginsenosides are dammarane saponins and can be divided into two classes: the protopanaxatriol class consisting primarily of Rg1, Rg2, Rf and Re, and the protopanaxadiol class consisting primarily of Re, Rd, Rb1 and Rb2. Ginseng also contains other saponins, polysaccharides, amino acids (in particular glutamine and arginine), essential oils and other compounds. Three new sesquiterpene hydrocarbons have also recently been isolated from the essential oil: panaxene, panaginsene and ginsinsene.

Ginsenosides Rh1, Rh2, and Rg3 are obtained from red ginseng as artifacts produced during steaming. It is likely that ginsenoside is actually a prodrug that is converted in the body by intestinal bacterial deglycosylation and fatty acid esterifi-cation into an active metabolite and therefore extrapolation from in vitro studies or studies in which ginseng or isolated constituents were given by injection must be made very cautiously.

Commercial ginseng preparations are variable in quality. An analysis of 50 products sold in 11 countries show that there is a large variation in the concentration of ginsenosides (from 1.9% to 9.0%). Some products were even found to be void of any specific ginsenosides. Some ginseng products have also been discovered to be contaminated with ephedrine. Therefore, it is essential that only quality ginseng products are used. Although the root hairs have a higher level of total ginsenosides than the main root, the main and lateral roots are the preferred medicinal parts. In all probability, it is the ratio of ginsenosides that is important and that other important compounds are also active.