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Abstract: Our previous study has revealed that malonyl-ginsenosides from Panax ginseng (PG-MGR) play a crucial role in the treatment of T2DM. However, its potential mechanism was still unclear. In this study, we investigated the anti-diabetic mechanisms of action of PG-MGR in high fat diet-fed (HFD) and streptozotocin-induced diabetic mice and determined the main constituents of PG-MGR responsible for its anti-diabetic effects. Our results showed that 16 malonyl ginsenosides were identified in PG-MGR by HPLC-ESI-MS/MS. PG-MGR treatment significantly reduced fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) levels and improved insulin resistance and glucose tolerance. Simultaneously, PG-MGR treatment improved liver injury by decreasing aspartate aminotransferase (AST) and alanine aminotransferase (ALT) expression. Furthermore, Western blot analysis demonstrated that the protein expression levels of p-PI3K/PI3K, p-AKT/AKT, p-AMPK/AMPK, p-ACC/ACC and GLUT4 in liver and skeletal muscle were significantly up-regulated after PG-MGR treatment, and the protein expression levels of p-IRS-1/IRS-1, Fas and SREBP-1c were significantly reduced. These findings revealed that PG-MGR has the potential to improve glucose and lipid metabolism and insulin resistance by activating the IRS-1/PI3K/AKT and AMPK signal pathways.

The ginseng endophytic bacteria F1 is a potential biocontrol agent for ginseng bacterial soft rot. In this paper,the chemotactic response of ginseng endophytic bacteria F1 on 8 kinds of sugar and amino acids was detected by capillary method to explore its biocontrol mechanism. The chemotactic response of F1 strain to 4 kinds of better chemotaxis substances such as glucose,glycine,L-rhamnoseand L-glutamic acid under parameters( concentration,time,temperature and pH) was studied. The results showed that under the same experimental conditions( incubation temperature 25 ℃,incubation time 60 min,chemotaxis concentration 1 mg·L~(-1)),ginseng endophytic bacteria F1 showed different degrees of response to the eight substances tested. The phenomenon of positive chemotaxis of the measured sugars and amino acids was obvious,and the chemotactic response to total ginsenosides was low. The degree of chemotaxis response is positively correlated with the chemotaxis index within a certain range of parameters,but as the temperature,p H,time,concentration and other factors continue to increase,the chemotaxis effect decreases,and F1 optimizes the chemotaxis of the four substances. The parameters are as follows: glucose: 25 ℃,10 mg·L~(-1),45 min,pH 7; glycine: 30 ℃,10 mg·L~(-1),75 min,pH7; L-rhamnose: 30 ℃,1 mg·L~(-1),30 min,pH 6; L-glutamic acid: 25 ℃,0. 1 mg·L~(-1),45 min,pH 8. The chemotactic response is more sensitive to low concentrations of chemotactic substances.

Our purpose was to evaluate chemotactic response of Ginseng bacterial soft-rot to ginseng root exudates. The exudates of plant roots has a significant influence on the population changes of rhizosphere microorganisms and chemotaxis is an important way in which many pathogens sense the signals of host plants and invade the host plants. In this study, with the capillary method, we tested the chemotactic responses of Ginseng bacterial soft-rot for three ginseng roots exudates under four chemotactic parameters (concentration, temperature, pH and time). The results showed that the chemotatic response of the Ginseng bacterial soft-rot for the ginseng roots exudates at the water layer where pH = 7 and the concentration was 0.0125 mg/L reached its peak value under the circumstance that the exudates was cultivated for 60 min at 25 °C. The chemotatic ratios were respectively 124.89% and 89.44%. For the butanol extract layer and the petroleum ether faction at the concentration of 0.125 mg/L and the pH value at 7, the ginseng roots exudatess reached peak values at 25 °C and 30 °C and 60 min and 75 min respectively, and the chemotatic ratios were respectively 139.64% and101.87%, and 115.29% and 81.36%. The three ginseng roots exudates had positive effects for the chemotaxis of the Ginseng soft-rot bacteria, but the effect declined as the concentration increased.

Ginsenosides are the main active ingredient and allelochemicals of Panax ginseng, and they play an important role in ginseng growth and in ecological adaptation. To study the influence of ginsenosides on soil microbial communities, the method of given exogenous total ginsenosides of different concentrations were used to study the influence of ginsenosides on new forest soil microbial community, evaluate the change of metabolic activity of microbial community and investigate the ecological effect of ginsenosides on soil microbial community. Results showed that, exogenous total ginsenosides promoted metabolic activity of microbial community in new forest soil at different concentrations compared with the control after 10 d and 40 d treatment. After 10 d,except for the Evenness index, all of the other indices indicated that the functional diversity of the soil microbial community in the new forest firstly increased then decreased with increase of the total ginsenosides concentration. The Substrate richness for 0.01 g•L⁻¹ soil treatment was significantly different from that of the control. After 20 d, 30 d and 40 d, except for the Evenness index, all of the other indices indicated that the functional diversity of the soil microbial community in the new forest increased with total ginsenosides. These results suggested that ginsenosids can change soil microbial community and microbial metabolic activity, which alter soil microbial ecology and accordingly affect the growth of ginseng with accumulation of ginsenosides in the soil.

Plate assay and spore germination method were used to study the chemotaxis response of Alternaria panax to arginine, glutamic acid, aspartic acid and threonine. The result showed that the optimum temperature of A. panax chemotaxis response to four amino acids were all 25 ℃. And chemotaxis responses of A. panax were different under conditions of different concentration and pH value. The chemotaxin reached to the highest under the condition of 2 mg•L⁻¹ and pH value was 7 for arginine, glutamic acid and threonine while 20 mg•L⁻¹ and pH value was 6 for aspartic acid . The data of chemotactic migration index (CMI) were 1.24, 1.38, 1.27, 1.31 and chemotactic growth rates(CGR) were 0.451 0, 0.353 0, 0.381 3, 0.228 8 and spores germination rates(SGR) were 57.33%，63%，56.67%，58% and the dry weight of mycelial (DWM) were 372.9, 348.5, 314.4, 390.2 mg•L⁻¹ respectively. It indicated that the low and middle concentration of amino acid had significant promoting effect on chemotaxis response of A. panax. As important substances generated in ginseng root, amino acids exhibited an efficient chemotactic effect on A. panax, and some even show inhibition effect under high concentration.

The chemotaxis response of Erwinia carotovora to different sugars and amino acids in four kinds of chemotactic parameters (concentration, time, temperature and pH ) was determined by capillary method. The results showed that when pH was 8, concentration was 0.025 mg•L ⁻¹, culture temperature was 25 ℃ and the duration was 60 minutes, the optimal chemotaxis rate of lysine was 2.509,when pH was 6, concentration was 0.25 mg•L ⁻¹, culture temperature was 25 ℃ and the duration was 60 minutes, the optimal chemotaxis rate of arginine was 2.218 8,when pH was 7, concentration was 0.25 mg•L ⁻¹, culture temperature was 30 ℃ and the duration was 60 minutes, the optimal chemotaxis rate of L-rhamnose was 3.091 2, when pH was 6, concentration was 0.25 mg•L ⁻¹, culture temperature was 30 ℃ and the duration was 45 minutes, the optimal chemotaxis rate of D-arabinose was 3.026 3. Sugars and amino acids had obvious chemotaxis with E. carotovora,the high concentration of carbohydrate and amino acid exited an inhibitory effect on chemotaxis response of E. carotovora, and the chemotaxis response decreased with the increase of concentration of carbohydrates and amino acids.

In this paper, three kinds of chemotactic parameters (concentration, temperature and pH) were determined by plate assay and spore germination method to research the chemotactic response of Botrytis cinerea and Alternaria panax, and their spores on total ginsenosides. The results showed that Botrytis cinerea had strong chemotactic response at the mid-concentration of total ginsenosides (cultivation temperature was 20 degrees C and pH value was 6), and the data of chemotactic migration index (CMI) was 1.293 0, chemotactic growth rate (CGR) was 0.476 0, spore germination rate (SGR) was 53%, and dry weight of mycelial (DWM) was 0.452 6 g x L(-1); however, Alternaria panax had strong chemotactic response at the low-concentration of total ginsenosides (cultivation temperature was 25 degrees C and pH value was 6), and the data of chemotactic migration index (CMI) was 1.235 4, chemotactic growth rate (CGR) was 0.537 0, spore germination rate (SGR) was 67%, and dry weight of mycelial (DWM) was 0.494 8 g x L(-1). The results indicated that the low and middle concentration (2, 20 mg x L(-1)) of total ginsenosides had significant promoting effect on chemotactic response of these two pathogens, and the spore germination, mycelial growth rate, dry weight of mycelial of them were also significantly improved by this chemotactic response, whereas it decreased as the increase of total ginsenosides concentration.

In this work, pressurized liquid extraction (PLE) of three acetophenones (4-hydroxyacetophenone, baishouwubenzophenone, and 2,4-dihydroxyacetophenone) from Cynanchum bungei (ACB) were investigated. The optimal conditions for extraction of ACB were obtained using a Box-Behnken design, consisting of 17 experimental points, as follows: Ethanol (100%) as the extraction solvent at a temperature of 120 °C and an extraction pressure of 1500 psi, using one extraction cycle with a static extraction time of 17 min. The extracted samples were analyzed by high-performance liquid chromatography using an UV detector. Under this optimal condition, the experimental values agreed with the predicted values by analysis of variance. The ACB extraction yield with optimal PLE was higher than that obtained by soxhlet extraction and heat-reflux extraction methods. The results suggest that the PLE method provides a good alternative for acetophenone extraction.

This paper is in order to study the anti-feeding and growth inhibition activity of toatal ginsenoside of ginseng stems and leaves against 4th-instar Mythimna separata larvae. Simulating natural growing condition indoors, on the base, To study the anti-feeding and growth inhibition activity of toatal ginsenoside against 4th-instar M. separata larvae by leaf disc test. The toatal ginsenoside appeared to be of significant antifeeding activity against 4th-instar M. separata larvae. The 4th-instar M. separata larvae fed on the leaves of Sorghum bicolor treated with 20, 10, 5 g · L(-1) toatal ginsenoside. At 8 h, non-selective anti-feeding rate were 88.67%, 64.40% and 47.36%, and selective anti-feeding rate were 62.49% , 44.29% and 34.19%; Compared with the photographic, The toatal ginsenoside conld make the development period had prolonged 13h in treated group. The toatal ginsenoside had significant inhibition effect on feeding and growth and development against 4th-instar M. separata larvae, and inhibition effect increases as the increase of concentration ginsenoside.

With the combination of deep Hubble Space Telescope Imaging and magnification due to gravitational lensing, the CLASH program offers an unprecedented opportunity to search for supernovae at high redshifts and detect some of the most distant galaxies as well. Unfortunately, the cluster field suffers from a high abundance of bright foreground sources and high background due to int ra-cluster light. To overcome these difficulties, we have developed a method of modeling and subtracting bright foreground light in the clusters using Fourier analysis. In this paper, I will present preliminary results based our method, which significantly increases the effective depth of the images, and efficiently characterizes distant background signals in the clusters.

Ginsenosides, the main effective components ofPanax ginsengC.A. Meyer andPanax quinquefoliusL., are important allelochemicals ofginseng. Although many studies have targeted the pharmacological, chemical, and clinical properties of ginsenosides, little is known about their ecological role inginsengpopulation adaptation and evolution. Pests rarely feed onginseng, and it is not known why. This study investigated the effects of total ginsenosides on feeding behavior and activities of acetylcholinesterase (AChE) and glutathione s-transferase (GST) inMythimna separata(Walker) larvae. The results showed that the total ginsenosides had significant antifeeding activity againstM. separatalarvae, determined by nonselective and selective antifeeding bioassays. In addition, the total ginsenosides had inhibitory effects on the activities of GST and AChE. The antifeeding ratio was the highest at 8 h, then decreased, and was the lowest at 16 h. Both GST and AChE activities decreased from 0 h to 48 h in all total ginsenosides treatments but increased at 72 h. Total ginsenosides had antifeeding activity againstM. separatalarvae and inhibitory effects on the activities of GST and AChE.

To study the anti-feeding effect of total ginsenoside of ginseng stems and leaves on Heliothis dipsacea larvae.The natural growing condition for lavae was simulated indoors. The anti-feeding effect of total ginsenoside on Heliothis dipsacea larvae was studied by leaf disc test.The total ginsenoside appeared showed a significant antifeeding effect. The Heliothis dipsacea larvae fed with the leaves of soybean treated with 2.0%, 1.0% and 0.5% total ginsenoside, respectively. At 8 h, non-selective anti-feeding rate were 93.40%, 83.42% and 75.19%, and selective anti-feeding rate were 77.53% , 73.58% and 58.86%.The toatal ginsenoside had significant inhibition effect on Heliothis dipsacea larvae, and inhibition effect increases as the increase of concentration ginsenoside.

Both ginseng and American ginseng can not be replanted on the same soil consecutively. The article reviews the development and progress of studies on the replant failure of ginseng and American ginseng with a special focus on allelopathy in recent years. The allelopathy effect in ginseng and American ginseng is reviewed from following aspects: collecting and extracting allelochemicals, effects of such allelochemicals on seeds germination, seedlings growth, antioxidant enzyme activities in ginseng roots, growth of ginseng pathogens and ginseng callus, and more. It is presumed that inhibitory allelopathy is one of the many possible factors contributing to the replant failure of ginseng and American ginseng. Based on that, the paper points out problems in current researches on the allelopathic effect of ginseng and American ginseng: the allelochemicals are consist of a mixture, which one plays the specific role is not clear; concentrating on a single allelochemical while ignoring the interaction among allelochemicals. It is suggested that further study for this area should be focused on the interactions among allelochemicals and interactions between allelochemicals and environmental impact factors. Another area of needed research is that of the migration and transformation of allelochemicals in soil and microbial involvement in allelopathy on the growth of ginseng and American ginseng.