[Transcriptome-wide identification and expression pattern analysis for Dof gene family in Panax ginseng from Jilin].

Dof(DNA binding with one finger), a unique class of transcription factors in plants, play an important role in seed development, tissue differentiation, and metabolic regulation. To identify the number and function of Dof gene family members in Panax ginseng, this study identified the members of Dof gene family in P. ginseng and systematically analyzed their structures, evolution, functional differentiation, expression patterns, and interactions using bioinformatics methods at the transcriptome level. At the same time, the association analysis of Dof genes from P. ginseng with key enzyme genes for ginsenoside synthesis was carried out to screen the candidate PgDof genes involved in the regulation of ginsenoside biosynthesis. The results showed that there were 54 genes belonging to the Dof gene family in P. ginseng from Jilin. All PgDof genes had Zf-Dof conserved motifs, implying that they were evolutionarily conserved and could be divided into five groups. Expression pattern analysis confirmed that the expression of PgDof gene family members in different tissues, different year-old P. ginseng, and different farm varieties varied significantly. Simultaneously, as revealed by "gene-saponin content" and "gene-gene" linkage analysis, an important candidate PgDof14-1 gene involved in the regulation of ginsenoside biosynthesis was obtained. From the established genetic transformation system of this gene in the hairy roots of P. ginseng, a positive hairy root clone was determined. This study has laid a theoretical foundation for the study of Dof gene family in P. ginseng.

[Expression of saponin biosynthesis related genes in different tissues of Panax quinquefolius].

The relationship between saponin content of Panax quinquefolius in different parts of the organization and expression of ginsenoside biosynthesis related gene was obtained by the correlation analysis between saponin content and gene expression. The 14 tissue parts of P. quinquefolius were studied, six saponins in P. quinquefolius. Samples (ginsenoside Rg1, Re, Rb1, Rc, Rb2 and Rd), group saponins and total saponins were determined by high performance liquid chromatography and vanillin-sulfuric acid colorimetric method. Simultaneously, the expression levels of 7 ginsenoside biosynthesis related genes (SQS, OSC, DS, ß-AS, SQE, P450 and FPS) in different tissues of P. quinquefolius were determined by Real-time fluorescence quantitative PCR. Although 7 kinds of ginsenoside biosynthesis related enzyme gene in the P. quinquefolius involved in ginsenoside synthesis, the expression of ß-AS and P450 genes had no significant effect on the content of monosodium saponins, grouping saponins and total saponins, FPS, SQS, OSC, DS and SQE had significant or extremely significant on the contents of single saponins Re, Rg1, Rb1, Rd, group saponin PPD and PPT, total saponin TMS and total saponin TS (P<0.05 or P<0.01). The biosynthesis of partial saponins, grouping saponins and total saponins in P. quinquefolius was affected by the interaction of multiple enzyme genes in the saponin synthesis pathway, the content of saponins in different tissues of P. quinquefolius was determined by the differences in the expression of key enzymes in the biosynthetic pathway. Therefore, this study further clarified that FPS, SQS, OSC, DS and SQE was the key enzyme to control the synthesis of saponins in P. quinquefolius by correlation analysis, the biosynthesis of ginsenosides in P. quinquefolius was regulated by these five kind of enzymes in cluster co-expression of interaction mode.

[Research of genes expression related to ginsenosides biosynthesis by methyl jasmonic acid in ginseng hair roots].

In order to obtain the expression of ginsenoside biosynthetic pathway related enzyme gene in ginseng hairy root under the control of elicitors, methyl jasmonate (MeJA) was added exogenously as elicitors. Ginseng hairy root clones induced by 4-year-old ginseng root was used as material, total saponin content in ginseng hairy root before and after MeJA treatment was determined by vanillin-sulfuric acid colorimetry, Meanwhile, relative expression of squalene synthase genes, squalene epoxidase genes, oxidized squalene cyclase genes, dammarenediol synthase genes, ß-amyrin synthase genes, cycloartenol synthase genes before and after MeJA treatment were determined by Real-time PCR. The optimum conditions of MeJA which added to ginseng hairy root were obtained, the optimum additional concentration was 6×10⁻4 µmol•L⁻¹, the optimum additional time was 22 d, and the optimum action time was 5 d. The addition of MeJA could improve the enzymatic activity of peroxidase (PPD), catalase (CAT) and peroxidase (PPD) in ginseng hairy root. The expression of SQS，SQE，OSC，DS and ß-AS genes of ginsenoside biosynthetic pathway increased significantly after MeJA treatment, while the change of CAS gene expression were not significant. The expression of key enzyme SQS，SQE，OSC，DS and ß-AS genes in ginsenoside biosynthetic pathway was consistent with the changes of PPD，CAT，PPO enzymatic activity.

[Research achievements on ginsenosides biosynthesis from Panax ginseng].

Panax ginseng is one of the famous rare medicinal herbs, and ginsenosides are the main active ingredient of ginseng is ginsenoside.They can be divided into three chemotypes: oleanane type, protopanaxadiol (PPD) type and the protopanaxatriol (PPT)type. Ginsenosides possess anti-thrombotic, anti-fatigue, anti-aging, cancer control, strengthening the immune system and many other effects. Rrogress has remarkably been made in pharmacology, efficacy and blosynthesis of ginsenosides.This review covers the recent research achievements of ginsenasides, which would be helpful for the relevant researchers to get useful information.

[Correlation of gene expression related to amount of ginseng saponin in 15 tissues and 6 kinds of ginseng saponin biosynthesis].

Fifteen tissues of 4-year-old fruit repining stage Jilin ginseng were chosen as materials, six kinds of monomer saponins (ginsenosides Rg1, Re, Rb1, Rc, Rb2 and Rd) content in 15 tissues was measured by HPLC and vanillin-sulfuric acid method. The relative expression of FPS, SQS, SQE, OSC, ß-AS and P450 genes in 15 tissues was analyzed by real-time PCR. The correlations between ginseng saponin content in 15 tissues of Jilin ginseng and biosynthetic pathway -related genes were obtained. The results showed that was a synergistic increase and decrease trend of positive linear correlation among six kinds of monomer saponin content, and there was a significantly (P < 0.01) positive correlation between monomer saponin content and total saponins content. Monomer saponin content and 6 kinds of enzyme gene correlation were different. Biosynthesis of ginseng total saponins and monomer saponin were regulated by six kinds of participation ginsenoside biosynthesis enzyme genes, the expression of these six kinds of genes in different tissues of ginseng showed collaborative increase and decrease trend, and regulated biosynthesis of ginseng ginsenoside by group coordinative manner.

[Fermentation transformed ginsenoside by Lactobacillus plantarum].

OBJECTIVE: To explore ginseng fermentation process by Lactobacillus plantarum, and to make part of total saponins transformed into more reactive ginsenoside Rd. METHOD: Microbial fermentation was carried out by still dark culture. Total saponins were extracted by Soxhlet extraction, and determined by UV visible spectrophotometry with colours reaction by vanillin-sulfuric acid. Ginsenoside Rd was determined by HPLC method. RESULT: The fermentation process was: MRS medium, 35 degrees C, pH 5.0, cultured for 2 days. The content of total saponins was inhance 32%, and the content of ginsenoside Rd was increased 4.864 mg x g(-1). CONCLUSION: The fermentation system's process was reasonable, and it's suitable for mass production, important significance for ginsenoside microbial transformation.