New achievements in ginseng research and its future prospects. 
In recent decades, scientists in Asian and Western countries have been paying great attention to ginseng research.  Today, more than 200 ginsenosides and non-saponin constituents have been isolated and identified.  Ginsenosides show biological activities only after being deglycosylated by intestinal bacteria.  Aglycone protopanaxadiol and protopanaxatriol show the highest bioactivities.  According to literature, the noticeable action of ginseng is that of delaying aging and especially increasing the nootropic effect, and it was found for the first time that Rg1 could increase hippocampal neurogenesis in vitro and in vivo under physiological and pathological circumstances.  This is one of primary mechanisms underlying many of its pharmacological actions on the central nervous system.  Rg1 was further shown to improve learning and memory in normal rats and mice.  The nootropic signaling pathway has also been carried out in normal rats, and the Rg1-induced signaling pathway is similar to the memory formation that occurs in mammals, suggesting that Rg1 may have a potential effect in increasing intellectual capacity in normal people.  Comparisons of chemical structures and pharmacologic functions between Panax ginseng and Panax quiquefolium were carried out by many scientists.  The conclusion is that each has its own characteristics.  There is no superiority or inferiority to the other.