Effects Of Elicitor And Culture Parameters On Spectrum Of Secondary Metabolites Of Ginseng Cells

Instability of growth and weak ability to accumulate desired ingredients are two keylimiting factors for its commercial application of scale suspension culture of plant cells.Herein, combined with the optimization of culture conditions, we introduced two kinds ofelicitors, including abiotic and biotic, to the panax cell culture base for improving theaccumulation of ginsenosides and polysaccharides, striking to depict the regulation ofsecondary metabolites of plant cells by artificial means. The major results are as follows:1.Sucrose was more efficient facilitating the accumulation of both ginsengpolysaccharide and total ginsenosides compared with other carbon resources. Phosphor actsas an important factor affecting the intracellular metabolism, moderate elevation of PO43-concentration led to increases in the contents of the above components, and their yieldsarrived at30.69±0.56mg/g and28.14±0.71mg/g, respectively. Calcium ion is a kind ofnecessary macronutrient and important secondary messenger for the normal growth of plantcells, and the total ginsenosides content/g dry weight increased by7.92mg after lifting theCa2+concentration to some extent.2.Combinations of plant growth regulators exert great effects on the cell growth andsecondary metabolite accumulation. It could gain the highest yield of cell mass when culturedon the media of MS supplemented with6-BA0.5mg/L+2,4-D1mg/L+NAA1mg/L; However,the combination of MS with6-BA1mg/L+2,4-D0.5mg/L+NAA1mg/L promoted thepolysaccharide accumulation with a peak yield of20.82±0.56mg/g, and the combination ofMS with6-BA1.5mg/L+2,4-D0.5mg/L+NAA2mg/L got the highest yield of ginsenoside of17.92±0.71mg/g.3.Under lumination and various temperatures, the cells cultured in the mediasupplemented with modest oxalate produced higher amounts of polysaccharide and totalginsenosides than those in the control, and the total ginsenosides content increased by5mg/gdry weight. These results demonstrated that oxalate was an efficient biotic elicitor instimulating the accumulation of ginseng callus secondary metabolites.4.Chitin of low molecular weight (～50,000Dlt), a biotic elicitor, facilitated the biosynthesis of polysaccharide and ginsenosides, and the contents of polysaccharide andginsenosides were increased by2.92mg/gand2.32mg/g, respectively. In addition, the ROScontent in the chitin-treated cells increased measurably, which might relate with theaccumulation of ginsenosides.5.The TLC analysis indicated that it could synthesize many kinds of ginsenosides in thecultured ginseng callus including some rare species of ginsenosides, e.g. Rh2and C-K.Moreover, the results here showed that it was contributive to the accumulation of C-K in thecells in the presence of low concentration of Hg2+, whereas, it was beneficial to Rh2accumulation with the addition of EGTA.6.Furthermore, the mechanism of ginsenoside and polysaccharide synthesis stimulatedby elicitor treatment was also investigated partly. The results suggested the relationship ofROS production with the stimulation of the above ingredients by oxalate.Generally, the data obtained in this study will be helpful for the scale production of rarespecies of Chinese herbs with the technology of cell engineering.