Preliminary study on response and its mechanism of ginsenoside biosynthesis in Panax ginseng to water regulation / 中国中药杂志

The study is aimed to explore the effect of soil moisture content on ginsenoside biosynthesis and explain its mechanism from the perspectives of antioxidant enzyme system and gene expression of key enzymes in the pathway of ginsenoside synthesis. In the study,two years old Panax ginseng was used as the experimental material and three moisture gradient,40% of saturated water content( W1),60%( W2),80%( W3) were set up. The content of 11 monomeric saponins were determined by HPLC. With GAPDH as a reference gene,six key enzymes( HMGR,SS,β-AS,CYP716 A47,CYP716 A52 v2,CYP716 A53 v2) in ginseng saponin synthesis pathway expression were analyzed by fluorescent quantitative PCR and the activities of superoxide dismutase( SOD),peroxidase( POD),catalase( CAT) activity and MDA content were also determined. With the increase of soil water,the content of ginseng saponin and biomass showed an increasing trend. PPD( Rb1,Rc,Rb2,Rd,Rh2,Rb3,Rg3),PPT( Rg1,Re,Rf) ginsenoside,Ro and total ginsenoside reached the maximum value on August 30,were 9.92,5.48,0.63 mg·g-1,respectively. During the whole regulation period,the antioxidant activity of W3 was greater than that of W1,and the MDA content was less than that of W1. At W3,expression levels of β-AS,CYP716 A47 and CYP716 A53 v2 showed an increasing trend,while HMGR and SS genes showed relatively stable expression levels under various water conditions. According to the correlation analysis,HMGR and SS genes in the W3 treatment group were significantly positively correlated with PPD,PPT ginsenoside and Ro,CYP716 A52 v2 gene was significantly positively correlated with Ro,and CYP716 A47 gene was significantly positively correlated with PPD ginsenoside. There was a significant positive correlation between β-AS gene and PPD ginsenoside in W1 and W2 treatment. Therefore,W3 is the optimum moisture content,ginseng total saponins and monomer saponin content is the highest,the gene closely correlation with content of saponins and more conducive to the accumulation of ginsenosides.

Effects of growing time on Panax ginseng rhizosphere soil microbial activity and biomass / 中国中药杂志

Using the field sampling and indoor soil cultivation methods, the dynamic of ginseng rhizosphere soil microbial activity and biomass with three cultivated ages was studied to provide a theory basis for illustrating mechanism of continuous cropping obstacles of ginseng. The results showed that ginseng rhizosphere soil microbial activity and biomass accumulation were inhibited observably by growing time. The soil respiration, soil cellulose decomposition and soil nitrification of ginseng rhizosphere soil microorganism were inhibited significantly (P <0.05), in contrast to the control soil uncultivated ginseng (R0). And the inhibition was gradual augmentation with the number of growing years. The soil microbial activity of 3a ginseng soil (R3) was the lowest, and its activity of soil respiration, soil cellulose decomposition, soil ammonification and soil nitrification was lower than that in R0 with 56.31%, 86.71% and 90. 53% , respectively. The soil ammonification of ginseng rhizosphere soil microbial was significantly promoted compared with R0. The promotion was improved during the early growing time, while the promotion was decreased with the number of growing years. The soil ammonification of R1, R2 and R3 were lower than that in R0 with 32.43%, 80.54% and 66.64% separately. The SMB-C and SMB-N in ginseng rhizosphere soil had a decreased tendency with the number of growing years. The SMB-C difference among 3 cultivated ages was significant, while the SMB-N was not. The SMB of R3 was the lowest. Compared with R0, the SMB-C and the SMB-N were significantly reduced 77.30% and 69.36%. It was considered by integrated analysis that the leading factor of continuous cropping obstacle in ginseng was the changes of the rhizosphere soil microbial species, number and activity as well as the micro-ecological imbalance of rhizosphere soil caused by the accumulation of ginseng rhizosphere secretions.

Effect of environmental factors on photosynthetic physiology and flavonoid constituent of Scutellaria baicalensis / 中国中药杂志

To discuss the effect of environmental factors and photosynthesis on the growing of plant and the content of active components in Scutellaria baicalensis, the photosynthetic physiology index and diurnal changes of flavonoid constituent of S. Baicalensis were observed and tested in flowering and fruiting stages, and in the meantime environmental parameters were recorded. The obtained data were analyzed data by using path analysis and gray correlation analysis. The results showed that PAR and SWC were important environmental factors impacting on photosynthesis of S. baicalensis. SWC, RH and Ca were important environmental factors impacting on baicalin content. PAR, Po and Ta were important environmental factors impacting on baicalein content.

Physiological ecology responses of Scutellaria baicalensis to drought and rewatering / 中国中药杂志

To study the physiological ecology responses of Scutellaria baicalensis to drought and rewatering of short period, we tested and analyzed photosynthesis and chlorophyll fluorescence parameters of S. baicalensis leaves processed by different ways of water treatment in drought and rewatering period, characteristic indexes of physiology and biochemistry of root SOD, POD, PAL, C4H, etc. and accumulation dynamic change of root baicalin and baicalein. The result showed that along with the worsening drought, P(n), T(r), G(s) and F(v)/F(m) of S. baicalensis declined in different water supply, and F(o) increased. The response of SOD and POD's activity in S. baicalensis root to drought in I and II was earlier than it in III. The response time and increase range of baicalin accumulation existed differences in different water supply, and the indexes regained after rewatering. Therefore, photosynthesis of S. baicalensis changed and it destroyed the antioxidant metabolism balance when soil water content decreased resulting from drought. The synergistic effect of defence mechanism launched by S. baicalensis, SOD, POD, PAL, C4H, baicalin and baicalein reduced active oxygen's damage to the cell.

Construction of prokaryotic expression vector, expression and purification of ginseng Cu/Zn superoxide dismutase / 中国中药杂志

The total RNA was extracted from ginseng leaves of Panax ginseng. The Cu/Zn-SOD gene was amplified via RT-PCR and the pET-28(a)-Cu/Zn-SOD expression vector was constructed. The pET-28 (a)-Cu/Zn-SOD recombinant plasmid was transformed into Escherichia coli BL21 (DE3) competent cells and was induced by IPTG in order to select optimal induction of expression conditions. The target protein was purified by the nickel ions (Ni ) affinity chromatography and the target protein enzyme activity was determinated by the xanthine oxidase method. The similarity of the Cu/Zn-SOD gene sequences and the Cu/Zn-SOD gene sequences of Korean ginseng in NCBI was 99. 00%. The target protein expression level was about 44.42%, and the molecular weight was 16.30 kDa after the pET-28(a)-Cu/Zn-SOD recombinants were induced by IPTG. The purified Cu/Zn-SOD protease activity reached 10,596.69 U x mg(-1). The P. ginseng pET-28(a)-Cu/Zn-SOD prokaryotic expression vector was built by the method of molecular biology, which provided the foundation for studying the Cu/Zn-SOD biology function.

Study on fitting growth density and best harvest time of Tribulus terrestris / 中国中药杂志

<p><b>OBJECTIVE</b>To study the suitable growth density and the optimal harvest time of Tribulus terrestris.</p><p><b>METHOD</b>Four growth densities were set with 60 cm breadth ridge and individual distance of 10, 20, 30 and 50 cm. The yield per individual and per unit area under the different growth densities were determined. Using yam saponin as a standard substance, the total saponin of T. terrestris was determined by UV spectrophotometry.</p><p><b>RESULT</b>The individual yield decreased with the density increase, but the difference between 30 cm and 50 cm individual distance was not substantial. The yield per unit area increased with density increase, and the difference between all densities was significant. The yield peak was in the last ten-day of August. The best leaves area index was 1.4 at the growth peak time. The total saponins content reached peaks respectively in the last ten-day of June and August, but the peak in last ten-day of August was consistent with the one of yield per unit area, and the total ashes content was the lowest at the same time.</p><p><b>CONCLUSION</b>The suitable growth density is 10 cm individual distance on the 60 cm breadth ridge. The optimal harvest time is in the last ten-day of August. The yield per unit area is 1 400 - 2 000 kg x hm(-2).</p>

Inhibition of magnesium lithospermate B on the c-Jun N-terminal kinase 3 mRNA expression in cardiomyocytes encountered ischemia/reperfusion injury / 药学学报

<p><b>AIM</b>To study the function of c-Jun N-terminal kinase 3 (JNK3) in the process of ischemic/reperfused heart injury and the mechanism underlying the protective action of magnesium lithospermate B (MTB), a bioactive compound isolated from Danshen.</p><p><b>METHODS</b>By in situ hybridization, JNK3 mRNA was detected in the ventricular preparations of the Langendorff ischemic/reperfused rat heart. The inhibitory effect of MTB on the expression of JNK3 mRNA was also investigated.</p><p><b>RESULTS</b>The purple and blue hybridization signals were located in the cytoplasm of the cardiomyocytes, which were weaker in the non-perfused hearts and stronger in the hearts encountered 30 min of ischemia and 30 min of reperfusion. Image analysis showed that the expression of JNK3 mRNA in the cardiomyocytes increased after 30 min of ischemia and 30 min of reperfusion, which showed significant difference compared with that in the cardiomyocytes of the non-perfused heart and the control heart (P < 0.05). Treatment with of 0.1, 1 and 10 mumol.L-1 MTB abolished the elevation of JNK3 mRNA expression in the ischemic/reperfused heart (P < 0.05).</p><p><b>CONCLUSION</b>JNK3 may be another component in the signal transduction pathway of ischemia/reperfusion induced cardiomyocyte apoptosis. MTB may protect the heart from ischemia/reperfusion injury by reducing apoptosis through inhibition of the JNK3 activity.</p>