Ginsenoside

Ginsenosides or panaxosides are a class of natural product steroid glycosides and triterpene saponins.

As a class, ginsenosides exhibit a large variety of subtle and difficult-to-characterize biological effects when studied in isolation.

[1] Ginsenosides can be isolated from various parts of the plant, though typically from the roots, and can be purified by column chromatography.

[5] As of 2021, the full conversion pathway to protopanaxadiol, protopanaxatriol, and oleanolic acid are known with each step having been assigned at least one gene.

[6] In the proposed pathway, squalene is synthesized from the assembly of two farnesyl diphosphate (FPP) molecules.

[9] Many UGT enzymes found in the genome of various Panax species are known to be responsible for attaching sugars onto the sterol skeleton, producing ginsenosides.

[9] Exposing in vitro cultures of ginseng cells to the plant defense signal methyl jasmonate causes increased production of ginsenosides.

[11] Steaming ginseng causes ginsenosides to lose their sugar and malonyl side chains, converting more polar molecules into the rarer (in nature), less-polar ones.

[13] Ginseng is generally consumed orally as a dietary supplement, and thus its component ginsenosides may be metabolized by gut flora to less-polar molecules.

Ginsenosides have been observed to increase internal antioxidant enzymes and act as a free-radical scavenger.

[7] Two broad mechanisms of action have been suggested for ginsenoside activity, based on their similarity to steroid hormones.

[12] Cell and tissue culture has also produced significant amounts of ginsenoside, especially when key biosynthetic genes are overexpressed.