Panax is a genus of perennial herbs in the family Araliaceae, the ivy family, comprising approximately 18 species. The genus is best known for ginseng — several of its species are among the most economically and medicinally significant plants in Asia and North America. All species are characterised by the presence of ginsenosides and gintonin, bioactive compounds that are the basis of ginseng's longstanding role in traditional medicine.
Panax belongs to a distinguished biogeographic group: it is one of around 60 plant genera that display a classical disjunct distribution between eastern Asia and eastern North America. This distribution is asymmetric — the vast majority of species are native to eastern and southeastern Asia, ranging from the Himalayas and China through Korea, Japan and Vietnam, while only two species (Panax quinquefolius, American ginseng, and Panax trifolius, dwarf ginseng) are native to eastern North America.
The genus is divided into two subgenera: subgenus Panax (the true ginsengs, including P. ginseng, P. quinquefolius, P. notoginseng and P. vietnamensis) and subgenus Trifolius (represented by the small, woodland P. trifolius). Well-known species include Panax ginseng (Asian ginseng, Korean ginseng), cultivated extensively in East Asia for its roots; Panax quinquefolius (American ginseng), highly valued in Chinese medicine and now subject to international trade controls due to wild-population pressure; and Panax notoginseng (san qi), used in traditional Chinese medicine for hemostatic applications. Panax vietnamensis (Vietnamese ginseng, ngoc linh) is notable as the species with the highest known ginsenoside content.
Etymology
The name Panax derives from Greek, meaning "all-healing", and shares the same etymological root as the word "panacea". Carl Linnaeus applied this name to the genus because he was aware of its wide use in Chinese traditional medicine.
Distribution
Panax has a disjunct east Asian–east North American distribution, a pattern shared by roughly 60 other plant genera. The majority of species (~16 of ~18) are native to eastern and southeastern Asia, from the Himalayas through China, Korea, Japan, and Vietnam. Only two species — Panax quinquefolius (eastern North America) and Panax trifolius (eastern North America) — occur in the New World.
Cultural Uses
Ginseng roots have been used in East Asian traditional medicine for thousands of years, primarily those of Panax ginseng (Asian ginseng) and Panax notoginseng (san qi). The genus name itself reflects this heritage, coined by Linnaeus in acknowledgment of their established role in Chinese medicine. Panax quinquefolius (American ginseng) became a major export commodity after its discovery in North America in the 18th century, as it was considered interchangeable with Asian ginseng in traditional Chinese medicine. The bioactive compounds responsible — ginsenosides and gintonin — are present across all Panax species.
Taxonomy Notes
The genus Panax L. belongs to the family Araliaceae (order Apiales). It is divided into two subgenera: subgenus Panax (which contains the commercially important true ginsengs, further organised into sections Panax and Pseudoginseng) and subgenus Trifolius (containing only P. trifolius). The genus displays a classic Tertiary relict disjunct distribution between eastern Asia and eastern North America. Several interspecific hybrids are recorded, including P. ginseng × P. quinquefolius.
