Production of ginseng saponin and polysaccharide by cell cultures ofPanax notoginseng andPanax ginseng

The effects of various combinations of the two kinds of phytohormones, auxin and cytokinin, on cell growth and production of ginseng saponin and polysaccharide were investigated in suspension cultures ofPanax notoginseng. It was found that a high concentration of kinetin (KT) (7 mg/L) seriously inhibited cell growth, but that of benzyl adenine (BA) did not. Under 0.7 mg/L of cytokinin (i.e., KT and BA), 2,4-dichlorophenoxy acetic acid (2,4-D) at 0.2 mg/L was better for the cell cultures than that at 2 or 20 mg/L; and for both naphthalene acetic acid (NAA) and indole acetic acid (IAA), 20 mg/L was their best level for the cell cultures. The highest cell concentration of 11.9 g/L (by dry wt) was obtained with the combination of 0.2 mg/L of 2,4-D and 0.7 mg/L of BA. The highest saponin content of 13.9% was achieved under 2.0 mg/L IAA and 0.07 mg/L KT; its highest production, i.e., 1.13 g/L, was obtained at 0.2 mg/L of 2,4-D and 0.7 mg/L of KT. Under 20 mg/L NAA and 0.7 mg/L KT, the highest polysaccharide content and production were reached, i.e., 16.4% and 1.86 g/L, respectively. In this work, the effects of phytohormones onP. ginseng cell cultures were also studied. A high saponin production of 1.78 g/L was observed at 10 mg/L of indole butyric acid and 0.1 mg/L of BA, and the highest production of polysaccharide (1.95 g/L) was reached with the combination of 10 mg/L NAA and 0.1 mg/L KT.     

A new ocotillol-type triterpenoid saponin from red American ginseng

A new ocotillol-type triterpenoid saponin, named 20(R)-pseudoginsenoside F(11) (1), was isolated along with pseudoginsenoside F(11) (2) from red American ginseng. The structure of the new saponin was elucidated as 6-O-[α-L-rhamnopyranosyl-(1?→?2)-β-D-glucopyranosyl]-dammar-20R, 24R-epoxy-3β, 6α, 12β, 25-tetraol by a combination analysis of NMR and mass spectrometry. The complete signal assignments of the two compounds were carried out by means of 2-D NMR spectral analysis.     

Micellar properties of quillaja saponin. 2. Effect of solubilized cholesterol on solution properties

The interaction between cholesterol and the surfactant quillaja saponin has been investigated by measuring the effect of cholesterol on surface and micellar properties of quillaja saponin solutions. The aggregation properties of cholesterol in water were studied using fluorescent probe methods, with results indicating that cholesterol alone does not form micelles in aqueous solution. However, surface tension, dye solubilization, and light scattering measurements show that cholesterol and saponin mixtures do form micelles at well-defined critical micelle concentrations (cmc). The cmc for saponin solutions saturated with cholesterol was generally higher than that for saponin alone, with the extent of the increase dependent on the source — and most likely the composition — of the saponin. The addition of salt decreases the cmc values, while temperature dependence of these values is more complex. Surface adsorption studies show that cholesterol preferentially adsorbs at the air/water interface, forming a closely-packed monolayer, but that saponin can partially displace the cholesterol at high saponin concentrations. Finally, the size, intrinsic viscosity and the aggregation number of the cholesterol/saponin micelles are larger than those of saponin micelles alone, with the radius of the micelles between 20 and 40% larger at 298 K. These results indicate that cholesterol most likely solubilizes within quillaja saponin micelles, and in the process has a substantial impact on the micelle structure and the energetics of micelle formation.     

Effect of methyl jasmonate on the ginsenoside content of Panax ginseng adventitious root cultures and on the genes involved in triterpene biosynthesis

Methyl jasmonate (MJ)-induced changes of triterpene saponins in Panax ginseng C.A. Meyer adventitious roots, and expression of the genes involved in triterpene biosynthesis, were analyzed. Compared with controls, expression of the squalene epoxidase and dammarenediol synthase genes was clearly upregulated and total saponin content increased in response to MJ. The highest total saponin content was obtained by use of 10 mg L^?1 MJ for 24 h, and was 4.76-fold greater than in the control group. Expression of the two genes associated with the cytochrome P450 family was no different from that in controls. The level of ginsenoside in the Rg group thus increased much less than that in the Rb group. This investigation showed that the total saponin content of ginseng adventitious root is related to gene expression in ginsenoside biosynthesis.     

Separation of the total glycosides of ginseng (panax ginseng C. A. Mey) on Sephadex

Summary The total glycosides of ginseng can be separated on Sephadex into two groups of materials, the first group containing the most polar glycosides and the second mainly two glycosides of less polarity-panaxosides A and C.     

Major metabolites of ginseng sapogenins formed by rat liver microsomes

Incubation of ginseng sapogenins with microsomes from rat liver resulted in formation of their 20,24-epoxides as major metabolites. Identification of the metabolites was performed by HPLC, FAB-MS and EI-MS.