1H NMR-based metabonomics of the hypoglycemic effect of polysaccharides from Cordyceps militaris on streptozotocin-induced diabetes in mice.

The crude polysaccharide was extracted from Cordyceps militaris. Material ratio of powder and water was 1:10. The polysaccharide was successively purified by Sevag and chromatography on Sephadex G-100 column to produce a polysaccharide fraction termed CBPS-II. The average molecular weight of CBPS-II was 1.273 × 103 kDa. The study was conducted to investigate the hypoglycemic effect of Cordyceps militaris polysaccharide on diabetic mice. Analysis of the clinical chemistry of the serum samples included serum creatinine (CRE), urea nitrogen (BUN), triglyceride (TG) and total cholesterol (TC). Results revealed that a certain dose of polysaccharide can alleviate the symptoms of metabolic disorders of diabetes, contributing to the body to restore the normal levels. The metabolic profiling method was adopted to find the related biomarkers and the metabolic pathway of diabetes. Moreover, results showed that 100 mg·kg-1 of Cordyceps polysaccharides can effectively reduce the blood glucose level of diabetic mice, thus regulating the metabolism of their energy, amino acids and intestinal microbes. The biomarkers noted in their metabolism were glucose, lactic acid, 3-hydroxy butyric acid, creatine, glutamate, valine, leucine, isoleucine and very low density lipoprotein (VLDL).

Structural analysis and antioxidant activity of the glycoside from Imperial Chrysanthemum.

A new glycoside, named as CG-1, was separated from Imperial Chrysanthemum with silica gel column chromatography. The purity was detected by TLC and HPLC. The crystal shape of CG-1 was consisting of a quadrangular and two rectangular pyramids. The analysis of DSC and TGA showed that the melting point of CG-1 crystal was 150.22 °C and had good thermal stability. The monosaccharide conformation analysis showed that it was d-glucose. The structure characteristics were compared by FT-IR, NMR spectroscopy and LC-MS and a molecular structure has been deduced which consistent with spectroscopic results. In vitro antioxidant results suggested that the glycoside extracted from Imperial Chrysanthemum could be effectively employed as natural antioxidant in health or functional food. This work is of significance to keep the antioxidant activity in the processing and application of Imperial Chrysanthemum.

Synthesis and In Vitro Anti-Influenza Virus Evaluation of Novel Sialic Acid (C-5 and C-9)-Pentacyclic Triterpene Derivatives.

The emergence of drug resistant variants of the influenza virus has led to a great need to identify novel and effective antiviral agents. In our previous study, a series of sialic acid (C-2 and C-4)-pentacyclic triterpene conjugates have been synthesized, and a five-fold more potent antiviral activity was observed when sialic acid was conjugated with pentacyclic triterpene via C-4 than C-2. It was here that we further reported the synthesis and anti-influenza activity of novel sialic acid (C-5 and C-9)-pentacyclic triterpene conjugates. Their structures were confirmed by ESI-HRMS, ¹H-NMR, and 13C-NMR spectroscopic analyses. Two conjugates (26 and 42) showed strong cytotoxicity to MDCK cells in the CellTiter-Glo assay at a concentration of 100 µM. However, they showed no significant cytotoxicity to HL-60, Hela, and A549 cell lines in MTT assay under the concentration of 10 µM (except compound 42 showed weak cytotoxicity to HL-60 cell line (10 µM, ~53%)). Compounds 20, 28, 36, and 44 displayed weak potency to influenza A/WSN/33 (H1N1) virus (100 µM, ~20-30%), and no significant anti-influenza activity was found for the other conjugates. The data suggested that both the C-5 acetylamide and C-9 hydroxy of sialic acid were important for its binding with hemagglutinin during viral entry into host cells, while C-4 and C-2 hydroxy were not critical for the binding process and could be replaced with hydrophobic moieties. The research presented herein had significant implications for the design of novel antiviral inhibitors based on a sialic acid scaffold.

The preparation of three selenium-containing Cordyceps militaris polysaccharides: Characterization and anti-tumor activities.

In the present work, three fractions of selenized Cordyceps militaris polysaccharides (SeCPS) named SeCPS- I, SeCPS- II and SeCPS- III were isolated and purified by ultra-filtration. Their selenium content were measured as 541.3, 863.7 and 623.3µg/g respectively by a graphite furnace atomic absorption spectroscopy. The monosaccharide comformation analysis showed that they were mainly consisted of D-Mannose, D-Glucose, and D-Galactose in mole ratios of 1:7.63:0.83, 1:1.34:0.31 and 1:3.77:0.41 respectively. Their structure characteristics were compared by IFR and NMR spectroscopy. Scanning electron microscopy (SEM) and Congo red (CR) spectrophotometric method were used to investigate their morphological characteristics and conformational transition. SeCPS-II showed the strongest anti-tumor effects judging from the result of in vitro anti-tumor assays against two tumor cell lines (hepatocellular carcinoma HepG-2 cells and lung adenocarcinom A549 cells).

Naphthoquinones from Onosma paniculatum with Potential Anti-inflammatory Activity.

Four new naphthoquinones (1-4), including a dimeric one, shikometabolin G (1), together with six known ones (6-10), were isolated from the methanol extract of Onosma paniculatum. Their structures were established based on the analysis of NMR and MS spectroscopic data. All of the compounds were evaluated for inhibitory effects on NO production in murine macrophage RAW 264.7 cells. Compounds 2, 3, 5, 6, 7, 8, and 10 displayed good activity on the inhibition of NO production (IC50 = 0.4-16.5 µM), suggesting the potential property of anti-inflammation.

Synthesis, characterization and antioxidant activity of selenium polysaccharide from Cordyceps militaris.

A purified selenium-containing derivatives of Cordyceps militaris polysaccharide synthesized using H2SeO3/HNO3 and BaCl2 as a catalyst was investigated in this paper. The reaction condition was optimized by selecting different reaction temperature and period. Afterward, the one with the highest Se content was purified by ultra-filtration device with a molecular cut off size of 10KDa. Followed by its structural characterizations. Results of IFR and 13C NMR spectroscopy indicated that C-6 substitution was predominant in selenized polysaccharide. The modified polysaccharide with molecular weight of 1998 KDa was mainly consisted of mannose, glucose and galactose in the mole ratios of with the mole ratios of 1:28.63:1.41. Thermogravimetric and morphological analyses of the samples were carried out by AFS, SEM and AFM. In addition, the in vitro antioxidant results suggested that selenium-containing polysaccharide should be applied as a novel selenium source in dietary supplements, with potent antioxidant properties.

Structural characterization and inhibition on α-d-glucosidase activity of non-starch polysaccharides from Fagopyrum tartaricum.

In the present study, the crude polysaccharide was extracted from Fagopyrum tartaricum and purified by Sephadex G-25 and G-75 column to produce a polysaccharide fraction termed TBP-II. Its average molecular weight was 26kDa. The structural characterization of TBP-II was investigated by gas chromatography, periodate oxidation-Smith degradation, Methylation and NMR. Congo red was applied to explore its advanced structures. The results revealed that chemical composition and structural characteristic of TBP-II was mainly consisted of galactose, arabinose, xylose and glucose with a molar ratio of 0.7:1:6.3:74.2. The backbone of TBP-II was composed of (1→4)-linked α-d-glucopyranosyl (Glcp), while the branches comprised of (1→3)-linked α-d-glucopyranosyl (Glcp), (1→6)-linked α-d-galactopyranosyl (Galp) and (1→2,4)-linked α-d-rhamnopyranosyl (Rhap). The structure of TBP-II was 1,3 and 1,6-branched-galactorhamnoglucan that had a linear backbone of (1→4)-linked α-d-glucopyranose (Glcp). Using Congo red assay showed that it was absent of triple helix structure. The α-d-glucosidase inhibitory activity of TBP-II was determined using acarbose as positive control. The result showed that the inhibition rate depended on the concentration of polysaccharides.

Preparation and inhibition on α-d-glucosidase of low molecular weight polysaccharide from Cordyceps militaris.

The structural properties and the inhibition on α-d-glucosidase activity of the low molecular weight (LCMPs-II) obtained from the optimized acid hydrolysis of the Cordyceps militaris polysaccharides (CMPs) were investigated in this paper. The LCMPs-II with a molecular weight of 28 KDa mainly composed of rhamnose, xylose and glucose with the molar ratio of 1: 2.19: 6.73 was separated from LCMPs-I which was the acid hydrolysis product of CMPs by chromatography on Sephadex G-100 column. The solubility of LCMPs-II was tested to be 32.12±1.05g in 100mL distilled water under 25°C. Its solubility was almost as twice as that of CMPs. Afterward, the structural features of LCMPs-II was investigated by a combination of chemical and instrumental analysis such as the specific rotation determination, FT-IR, periodate oxidation-Smith degradation, Congo-red, GC, scanning electron microscope and NMR. The results showed that the optical rotation of LCMPs-II was +25° and it was 1,3-branched-rhamnoxyloglucan which had a linear backbone of (1→4)-linked α-d-glucopyranose (α-d-Glcp units).

Preparation and activity evaluation of chrysin-ß-D-galactopyranoside.

Chrysin-ß-D-galactopyranoside was efficiently synthesized, evaluated for its inhibitory activities against H22 cell lines compared with chrysin, the scavenging of hydroxyl radical, DPPH radical and superoxide anion, inhibitory effect against bacteria and fungi. The structures of all compounds were fully characterized by spectroscopic data (NMR, MS). The anti-tumor, antioxidant and antimicrobial activities of chrysin-ß-D-galactopyranoside were proved to be enhanced significantly compared with chrysin.

Effects of cultural medium on the formation and antitumor activity of polysaccharides by Cordyceps gunnii.

The effects of culture medium composition (i.e., carbon and nitrogen sources) on the growth of mycelia, molecular weight distribution and antitumor activity of intracellular polysaccharides (IPS) from Cordyceps gunnii were investigated. Sucrose and peptone were proved to be the best carbon and nitrogen sources for mycelia growth and remarkably improved IPS production. When the sucrose concentration was 2.0%, the mycelium yield reached up to 15.94±1.26 g/L, but with lower IPS yield; whereas the sucrose concentration was 4.5%, IPS yield reached to a maximum of 138.78±3.89 mg/100 mL. The effects of different carbon/nitrogen (C/N) ratios with equal amounts of carbon source matter on the mycelia and IPS formation were optimized. It found that the yield of mycelia and IPS were both reached to the highest at a C/N ratio of 10:3. In addition, the IPS had the highest macro molecular polysaccharide content and antitumor activity when sucrose concentration was 3.5% and the C/N ratio was 10:1.5. Thus, there was a positive correlation between molecular weight distribution and antitumor activity of IPS by C. gunnii.

Efficient synthesis and activity of beneficial intestinal flora of two lactulose-derived oligosaccharides.

Lactulose is considered as a prebiotic because it promotes the intestinal proliferation of Lactobacillus acidophilus which is added to various milk products. Moreover, lactulose is used in pharmaceuticals as a gentle laxative and to treat hyperammonemia. This study was aimed at the total synthesis of two Lactulose-derived oligosaccharides: one is 3-O-ß-d-galactopyranosyl-d-fructose, d-fructose and ß-d-galactose bounded together with ß-1,3-glycosidic bound, the other is 1-O-ß-d-galactopyranosyl-d-fructose, d-fructose and ß-d-galactose bounded together with ß-1,1-glycosidic bound, which were accomplished in seven steps from d-fructose and ß-d-galactose and every step of yield above 75%. This synthetic route provided a practical and effective synthetic strategy for galactooligosaccharides, starting from commercially available monosaccharides. Then we evaluated on their prebiotic properties in the search for potential agents of regulating and improving the intestinal flora of human. The result showed that the prebiotic properties of Lactulose-derived oligosaccharides was much better than Lactulose. Among them, 3-O-ß-d-galactopyranosyl-d-fructose displayed the most potent activity of proliferation of L. acidophilus.

Structural analysis and immunostimulatory activity of glycopeptides from Paecilomyces sinensis.

The parasitic fungus, Paecilomyces sinensis, is used to produce Cordyceps materials as a succedaneum of natural Cordyceps sinensis (C. sinensis) in China. In this work, a glycopeptide (CPS-II) was isolated and purified from Paecilomyces sinensis. The result of HPLC indicated that CPS-II was a glycopeptide. The estimated average molecular weight of CPS-II was 2 × 10(6) Da. FTIR, methylation, periodate oxidation, Smith degradation, (1)H NMR, (13)C NMR and CD were used for its structural analysis. The glycopeptide CPS-II was mainly composed of (1 → 3), (1 → 4) connected glucose and galactose as the backbone, there are (1 → 2,3,6) connected glucose, (1 → 3,6) connected mannose, and (1 → 6) connected galactose. Cell proliferation assay and morphological observations indicated that in a certain range of concentrations and time, CPS-II can significantly improve the proliferation activity of RAW264.7 cells.

Synthesis and anti-cancer activity evaluation of 5-(2-carboxyethenyl)-isatin derivatives.

A series of novel di- or trisubstituted isatin derivatives were designed and synthesized in 5-6 steps in 25-45% overall yields. Their structures were confirmed by 1H NMR and 13C NMR as well as LC-MS. The anticancer activity of the fourty-three new isatin derivatives against human T lymphocyte cells Jurkat was evaluated by MTT assay in vitro. SAR study suggested that the combination of 1-benzyl and 5-[trans-2-(methoxycarbonyl)ethen-1-yl] substitution greatly enhanced their cytotoxic activity. Among them, compound 2h was shown to have a significant cytotoxic activity with an IC50 value of 0.03 µM, more than 330-fold higher than that of it's mother molecule isatin. Investigation of the cell morphology changes and annexin-V/PI staining study demonstrated that compound 2h inhibited the proliferation of Jurkat cells by inducing apoptosis. Since compound 2h induced the dissipation of mitochondrial membrane potential and the activation of caspase-3, it was obvious that compound 2h inhibited the proliferation of Jurkat cells through the mitochondrial apoptotic pathway. Other than this, compound 2h exerted inhibition effect to many other tumor cells and only showed weak cytotoxic to human normal cells suggesting that compound 2h possessed a broad range of anticancer spectrum and high safety to normal cells.

Structural properties of polysaccharides from cultivated fruit bodies and mycelium of Cordyceps militaris.

The structural properties of polysaccharides, respectively, obtained from the fermented mycelium and cultivated fruiting bodies of the Cordyceps militaris were investigated and compared in this paper. First, the crude polysaccharides were extracted from the mycelium and the fruiting bodies, respectively. The polysaccharides were successively purified by Sevag and chromatography on Sephadex G-100 column to produce two polysaccharides fractions termed CMPS-II and CBPS-II, respectively. The average molecular weights of CMPS-II and CBPS-II were 1.402×10(3) kDa and 1.273×10(3) kDa, respectively, and they were mainly composed of mannose, glucose and galactose in the mole ratios of 1:28.63:1.41 and 1:12.41:0.74, respectively, for CMPS-II and CBPS-II. Afterward, the structural features of CMPS-II and CBPS-II were investigated by a combination of chemical and instrumental analysis, such as FT-IR, periodate oxidation-Smith degradation, GC-MS, NMR and methylation analysis. The results indicated that structurally, both CMPS-II and CBPS-II were 1,3-branched-galactomannoglucan that had a linear backbone of (1→4)-linked α-D-glucopyranose (Glcp). Congo-red test revealed that CMPS-II and CBPS-II existed as triple-helical chains in 0.05-0.15 M NaOH solution.

Low toxic and high soluble camptothecin derivative 2-47 effectively induces apoptosis of tumor cells in vitro.

The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2-47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2-47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC50) of 2- to 3-fold lower than HCPT as a control. In particular, 2-47 inhibited the proliferation of Jurkat cells with an IC50 of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2-47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2-47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2-47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2-47 solutes in CHCl3 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2-47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro.

Influence of fermentation conditions on polysaccharide production and the activities of enzymes involved in the polysaccharide synthesis of Cordyceps militaris.

The influence of different fermentation conditions on intracellular polysaccharide (IPS) production and activities of the phosphoglucomutase (PGM), UDPG-pyrophosphorylase (UGP), phosphoglucose isomerase (PGI), UDPG-dehydrogenase (UGD), and glucokinase (GK) implicated in metabolite synthesis in Cordyceps militaris was evaluated. The highest IPS production (327.57 ± 6.27 mg/100 mL) was obtained when the strain was grown in the optimal medium containing glucose (40 g · L(-1)), beef extract (10 g · L(-1)), and CaCO3 (0.5 g · L(-1)), and the initial pH and temperature were 7 and 25 °C, respectively. The activities of PGM, UGP, and PGI were proved to be influenced by the fermentation conditions. A strong correlation between the activities of these enzymes and the production of IPS was found. The transcription level of the pgm gene (encoding PGM) was 1.049 times and 1.467 times compared to the ugp gene and pgi gene (encoding UGP and PGI), respectively, in the optimal culture medium. This result indicated that PGM might be the highly key enzyme to regulate the biosynthesis of IPS of C. militaris in a liquid-submerged culture. Our study might be helpful for further research on the pathway of polysaccharide biosynthesis aimed to improve the IPS production of C. militaris.

Structural characterization and anti-tumor activity of polysaccharide produced by Hirsutella sinensis.

HSP-III, a novel homogeneous polysaccharide with 513.89 kDa molecular weight, was fractionated from submerged cultures of Hirsutella sinensis by Sevag and chromatography on Sephadex G-100 column. The total sugar content of HSP-III was amounted to 89.87%. Based on the results of high performance gel permeation chromatogram (HPGPC), FT-IR, NMR spectroscopy, GC, periodate oxidation-smith degradation and methylation analysis, it showed that HSP-III was mainly composed of mannose and galactose, and a small amount of rhamnose, arabinose, xylose, and glucose. The molar ratio of Rha:Ara:Xyl:Man:Glu:Gal was 1.00:2.44:13.11:74.13:13.80:54.39. The main chain of HSP-III was majorly composed of (1→3) glucose. The tumor inhibition ratio on H22 cell was 79.04% at 100 µg/mL of HSP-III.

Synthesis and anti-cancer activity evaluation of novel prenylated and geranylated chalcone natural products and their analogs.

Four natural chalcones bearing prenyl or geranyl groups, i.e., bavachalcone (1a), xanthoangelol (1b), isobavachalcone (1c), and isoxanthoangelol (1d) were synthesized by using a regio-selective iodination and the Suzuki coupling reaction as key steps. The first total synthesis of isoxanthoangelol (1d) was achieved in 36% overall yield. A series of diprenylated and digeranylated chalcone analogs were also synthesized by alkylation, regio-selective iodination, aldol condensation, Suzuki coupling and [1,3]-sigmatropic rearrangement. The structures of the 11 new derivatives were confirmed by (1)H NMR, (13)C NMR and HRMS. The anticancer activity of these new chalcone derivatives against human tumor cell line K562 were evaluated by MTT assay in vitro. SAR studies suggested that the 5'-prenylation/geranylation of the chalcones significantly enhance their cytotoxic activity. Among them, Bavachalcone (1a) displayed the most potent cytotoxic activity against K562 with IC50 value of 2.7 µM. The morphology changes and annexin-V/PI staining studies suggested that those chalcone derivatives inhibited the proliferation of K562 cells by inducing apoptosis.

[System of ns time-resolved spectroscopy diagnosis and radioprotection].

Cathode plasma of high current electron beam diode is an important research on high power microwave and strong pulsed radio accelerator. It is a reliable method to study cathode plasma by diagnosing the cathode plasma parameters with non-contact spectroscopy measurement system. The present paper introduced the work principle, system composition and performance of the nanosecond (ns) time-resolved spectroscopy diagnosis system. Furthermore, it introduced the implementing method and the temporal relation of lower jitter synchronous trigger system. Simultaneously, the authors designed electromagnetic and radio shield room to protect the diagnosis system due to the high electromagnetic and high X-ray and γ-ray radiation, which seriously interferes with the system. Time-resolved spectroscopy experiment on brass (H62) cathode shows that, the element and matter composition of cathode plasma is clearly increase with the increase in the diode pulsed voltage and current magnitude. The spectroscopy diagnosis system could be of up to 10 ns time resolve capability. It's least is 2 ns. Synchronous trigger system's jitter is less than 4 ns. The spectroscopy diagnosis system will open a new way to study the cathode emission mechanism in depth.