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The present study reports the presence of a β-D-fructopyranosyl-(2→1)-linked fructan in nature for the first time, with a β-D-fructofuranosyl-(2→1)-linked fructan in a mixture from Codonopsis pilosula. High-performance gel permeation chromatography (HPGPC) shows that the molecule weights of these two fructans are 2.33 and 1.31 kDa. Their structures were analyzed by 1D and 2D NMR.

Fructans are generally divided into two different types: β-D-fructofuranosyl-(2→1)-linked inulin and β-D-fructofuranosyl-(2→6)-linked levan. Previously, Radix Codonopsis was found to be rich in inu...

The electrochemical corrosion behavior of Ni-P coating in 3.5 wt% NaCl solution-containing CO2 and H2S was investigated using electrochemical methods and surface characterization techniques. The results show that the presence of H2S can enhance the CO2 corrosion of Ni-P coated carbon steel by affecting both anodic and cathodic processes. The adsorbed layer only exists in the very early stage of corrosion and barely improves the anticorrosion performance of the coating. The formation of corrosion products (NiO and Ni3S2) renders temporary protection during immersion, but the addition of H2S accelerates the diffusion process at the electrolyte/coating interface and promotes the electrolyte penetration through the coating, causing severe localized corrosion and coating disbondment. A corrosion model is proposed to illustrate the corrosion and degradation process of Ni-P coated steel in the CO2/H2S/Cl− environment.

A new cycloartanyl ester, named codonopilate D (1), was isolated from the roots of Codonopsis pilosula (Franch.) Nannf. The structure of compound 1 was elucidated by extensive spectroscopic analysis including UV, IR, MS, and NMR data. Compound 1 exhibited the potential of inhibiting LPS-induced NO production in RAW 264.7 cells.

Antifouling coatings have attracted much attention in applications of industrial equipment and systems. The accumulation of foulants on downhole equipment used in the steam-assisted gravity drainag...

To reduce the amount of greenhouse gas emissions and remedy related environmental damage, the research on carbon capture and storage (CCS) is gaining momentum and so is the search for a more effective way to control corrosion of pipeline steel used to transport impure supercritical (SC) CO2. Herein, we prepared an electroless high-phosphorus Ni-P coating and, for the first time, systematically explored the underlying mechanism of the interfacial process in applying Ni-P coating to protect pipeline steel that transports impure SC CO2. It is found that, benefiting from the formation of a protective surface film, Ni-P coating significantly mitigates the corrosion effects from SC CO2 and impurities (e.g., O2 and NO2), especially the synergistic effect of impurities. Concurrently, it effectively avoids the localized corrosion resulting from nonuniform adsorption of the aqueous phase. Although O2 and NO2 can degrade the coating through boosting water precipitation, deteriorating the water chemistry, and reducing the surface film protectiveness, the corrosion inhibition efficiency of Ni-P coating is invariably higher than 80%, independent of the varying causticity of SC CO2 streams, demonstrating that the coating has a superior stability toward corrosion attack. The as-prepared Ni-P coating undoubtedly holds great potential as an alternative for corrosion control of CO2 transport pipeline in the CCS industry. This work provides a new, feasible method to ensure the safe and efficient operation of CCS.

This study investigated the effect of flowing velocity and impact angle on the fluid-accelerated corrosion (FAC) of X65 pipeline steel in a wet CO2-containing environment by corrosion morphology analysis, electrochemical measurement, and hydromechanical numerical analysis. It has been found that the corrosion behavior was controlled by the ion diffusion rate and shear stress due to the flowing gas. With an increase in the flowing velocity, the pitting corrosion initially decreased and then increased when the flowing velocity exceeded 14 m/s; this increase is caused by the augmentation of shear stress. When the impact angle decreased, the position of serious corrosion gradually moved outwards.

Objective. To evaluate the prebiotic effects of Codonopsis pilosula polysaccharide (CPP) on human gut bacteria in vitro. Methods. Codonopsis Radix was extracted with water at 100°C, and the extract was precipitated by 80% ethanol to obtain CPP. Human fresh fecal samples were collected from three healthy adults and used to ferment CPP. The fermented samples were collected to be analyzed by 16S rRNA sequencing. Results. The results showed that CPP exhibited significantly the stimulation on the growth of genus Bifidobacterium of human gut bacteria (Padj 0.05), which was likely associated with the limited samples (n = 3). Conclusion. CPP has the potential to stimulate the growth of Bifidobacterium of the human gut bacteria and to be benefit to human health.

Objective To evaluate the prebiotic effects of Codonopsis pilosula polysaccharide (CPP) on human gut bacteria in vitro. Methods Codonopsis Radix was extracted with water at 100°C, and the extract was precipitated by 80% ethanol to obtain CPP. Human fresh fecal samples were collected from three healthy adults and used to ferment CPP. The fermented samples were collected to be analyzed by 16S rRNA sequencing. Results The results showed that CPP exhibited significantly the stimulation on the growth of genus Bifidobacterium of human gut bacteria (Padj 0.05), which was likely associated with the limited samples (n = 3). Conclusion CPP has the potential to stimulate the growth of Bifidobacterium of the human gut bacteria and to be benefit to human health.

This study presents an investigation of the on-site corrosion of carbon steel pipes with stainless steel mesh screens in a steam flood well in the Athabasca oil sand reservoirs to determine the failure patterns and mechanisms. To mitigate the corrosion of carbon steel, several candidate materials were selected, and their corrosion resistance was investigated. In this work, the corrosion behavior and film characteristics of carbon steel pipes were studied by surface analysis techniques such as scanning electron microscopy, energy dispersive spetrocsopy and X-ray diffraction. Corrosion resistant alloys (proRSf and proRSc), anti-corrosion coating (proRA05a) and pre-treated steel (proRAQa) were considered as alternative materials to carbon steel (proRAa and proRAb) and their corrosion protection performance in brine solution was evaluated by electrochemical methods such as potentiodynamic sweep and electrochemical impedance spectroscopy. Results show that severe erosion-corrosion occurred on inner wall of the pipes and caused significant wall-thinning of pipes along with localized corrosion damages, which is the dominant reason for base pipe failure. In spite of the slight corrosion on outer wall of the base pipe, severe localized corrosion appeared at the interface between the carbon steel pipe and stainless steel mesh screens due to the galvanic corrosion effect of dissimilar metals. The corrosion rates of the corrosion-resistant materials were two or three orders of magnitude lower than that of carbon steel. The corrosion resistance ranking order is proRSc > proRSf > proRA05a > proRAQa > proRAa > proRAb. This study improves the material selection procedure in thermal operations by investigating several alternatives to carbon steel. It also provides a testing procedure to assess the corrosion resistance of the material in thermal applications.

This work investigated the flow-accelerated corrosion (FAC) behavior of 13Cr in a wet CO2-containing environment at different flowing gas velocities and impinging angles, with the natural-gas pipeline environment simulated by a self-assembled impingement jet system. Surface morphology determination, electrochemical measurements, and hydromechanics numerical analysis were carried out to study the FAC behavior. The results demonstrate that pitting corrosion was the primary mode of corrosion in 13Cr stainless steel. High-flow-rate gas destroyed the passive film and decreased the pitting potential, resulting in more serious corrosion. The corrosion degree with various impact angles showed the following order: 90° > 60° > 45°. The shear force and the electrolyte from the flowing gas were concluded to be the determinant factors of FAC, whereas the shear force was the main factor responsible for destroying the passive film.

The effects of defect on the localized corrosion and disbonding behavior of electroless Ni-P coating in CO2 environment were investigated using electrochemical methods and surface characterization techniques. The results show that the Ni-P coating has a good resistance to corrosion disbonding at open circuit potential, even with an artificial defect in the coating. The localized corrosion and the disbonding of the coating occur after the acceleration by cathodic polarization because the coating defects provide effective pathways for the electrolyte to transport through the coating and along the coating/substrate interface laterally. A corrosion model is proposed to well interpret this phenomenon.

A smart electroless Ni-P composite coating incorporated with pH-responsive benzotriazole (BTA)-loaded nanocapsules was successfully fabricated and applied on N80 carbon steel for the first time, and the improved corrosion resistance was evaluated by electrochemical measurements and surface characterization techniques. The coating incorporated with the functionalized nanocapsules exhibits excellent anti-corrosion performance in the CO2-saturated brine. This is originated from the filling of the nanocapsules into intrinsic micropores of the coating, which impairs the electrolyte penetration at the beginning stage of immersion, and the release of BTA when triggered by the local acidification of the micropores due to penetration of aggressive medium as immersion further proceeds. Furthermore, the incorporated nanocapsules endow the smart coating with a good anti-corrosion stability, showing a maximum inhibition efficiency of over 80%. The well-protected coating surface shows much less corrosion pits and no evidence of lateral coating disbondment at the coating/substrate interface according to the surface characterization results.

A glucan named as CPC was obtained from the roots of Codonopsis pilosula and its structure was determined by HPGPC, IR, GC–MS, and NMR. HPGPC showed that CPC was a homogeneous polysaccharide and exhibited a molecular weight (Mp) of 1698 Da according to the equation of standard molecular weight (lg Mp = −0.1869 tR + 9.7386). The results from NMR and GC–MS demonstrated that the main linkages in CPC were 1-linked β-D-glucose, 1,4-linked α-D-glucose, and 1,4,6-linked α-D-glucose in the molar ratio of 1.0:3.8:1.0, which indicated that the structure of CPC exhibited the backbone of 1,4-linked α-D-glucose and the branched chains of 1,6-linked β-D-glucose. The immunomodulatory activity indicated that CPC showed the significant induction on the productions of NO, ROS, iNOS, TNF-α, IL-6, IL-1β and IL-10 and the mRNA expressions of iNOS, TNF-α, IL-6, IL-1β and IL-10 in RAW 246.7 cells. These data suggested that CPC was potential to human health by regulating immunity.

The effects of Ca2+ on the CO2 corrosion behavior and film characteristics of N80 carbon steel and electroless Ni–P coating at high temperature and high pressure were investigated by immersion tests, in-situ electrochemical measurements, surface characterization techniques and water chemistry analysis. The results demonstrate that the corrosion of N80 steel is significantly influenced by Ca2+ concentration, however Ni–P coating exhibits exceptional corrosion resistance regardless of Ca2+ concentration. The microstructure and compactness of FeCO3 corrosion film is altered with the increased incorporation of Ca2+, thereby affecting the electrolyte penetration and the corrosion rate consequently. The added Ca2+ also impacts the water chemistry of the aqueous phase, postponing the FeCO3 precipitation. Meanwhile, the superb corrosion resistance of Ni–P coating is owing to the protection of the formed NiO/Ni(OH)2 film and the absence of scale formation.

An impingement jet system was used to study the corrosion of API X65 steel in a wet CO2-containing environment via electrochemical tests, surface analysis technique and computational fluid dynamics simulation. The corrosion rate decreased in the wet environment compared to that in the bulk solution. When under flow condition, corrosion rate increased with the flowing velocity, especially when above the critical flowing velocity. Continuous electrolyte film was formed and electrochemical reaction started to occur in about 70% RH, and the critical RH appeared at 70–80%, above which pit size and amount remarkably increased with flow velocity.

To reduce the amount of greenhouse gas emissions and remedy related environmental damage, the research on carbon capture and storage (CCS) is gaining momentum and so is the search for a more effective way to control corrosion of pipeline steel used to transport impure supercritical (SC) CO

Bioactive metabolites in Codonopsis pilosula are of particular interest as an immunostimulant. Methyl jasmonate (MeJA) plays an important role in the elicitation of metabolite biosynthesis. Here, we explored the response of metabolites to MeJA elicitation in C. pilosula adventitious roots and multiple shoots. The results showed that the biomass, polysaccharide, and lobetyolin content of adventitious roots exhibited the highest increases with 100 &micro, mol&middot, L&minus, 1 MeJA at the 16th day of subculture, whereas the atractylenolide III (a terpenoid) content increased extremely with 50 &micro, 1 MeJA treatment at the 7th day of subculture. In addition, the biomass and lobetyolin content significantly increased at the 4th day after treatment. Similarly, the polysaccharide and lobetyolin content increased in multiple shoots. Further identification of different metabolites responding to MeJA by 1H-NMR showed an extremely significant increase of the lobetyolinin level, which coincided with lobetyolin. Accordingly, the precursor, fatty acids, showed a highly significant decrease in their levels. Furthermore, a significant increase in &beta, d-fructose-butanol glycoside was detected, which was accompanied by a decrease in the sucrose level. Accordingly, the enzyme genes responsible for terpenoid and carbohydrate biosynthesis, CpUGPase, and CpPMK, were up regulated. In conclusion, MeJA promoted culture growth and accelerated bioactive metabolite accumulation by regulating the expression of the metabolite biosynthesis related genes, CpUGPase and CpPMK in C. pilosula.

Objective. To isolate the hypoglycemic bioactive components from leaves of Psidium guajava and evaluate their AMP-activated protein kinase (AMPK) activities. Methods. A variety of column chromatography was used for the isolation of compounds, and nuclear magnetic resonance (NMR) and mass spectrum (MS) were used for the structure identification of compounds. AMP-activated protein kinase (AMPK) activity of compounds obtained from leaves of Psidium guajava was evaluated in L6 rat myoblast cells and L02 human hepatic cells by western blot. Results. Six principal flavonoids largely present in the leaves of Psidium guajava, quercetin (1), quercetin-3-O-α-L-arabinofuranoside (2), quercetin-3-O-α-L-arabinopyranoside (3), quercetin-3-O-β-D-galactopyranoside (4), quercetin-3-O-β-D-glucopyranoside (5), and quercetin-3-O-β-D-xylopyranoside (6), were obtained and compound 1–6 exhibited significant activity on AMPK activation both in L6 cells and L02 cells (p<0.01) compared with Control. In particular, the effects of quercetin on AMPK activation were extremely significant compared with Control (p<0.001). Conclusions. These findings demonstrated that these flavonoids had potential for the activation of AMPK and hypoglycemic activity.

The electroless Ni-Mo-P/Ni-P composite coating was applied on N80 carbon steel, and the effects of Mo addition and heat treatment on the corrosion resistance enhancement in CO2/H2S/Cl− brine were studied by electrochemical measurements and surface analysis techniques. The Mo addition in the as-deposited Ni-P coating causes the microstructural transformation from amorphous to crystalline due to the reduced P content, thereby suffering severe corrosion. The impaired corrosion performance of as-deposited Mo-incorporated coating is also originated from the absence of the oxide film on the coating surface. Nonetheless, the heat-treated Ni-Mo-P/Ni-P coating exhibits desirable corrosion resistance, which is reflected by the outstanding corrosion inhibition efficiency (η = 96.1%). Heat treatment facilitates the formation of Ni4Mo phase and more importantly, the growth of an oxide film consisting of nickel and molybdenum oxides (H2S-immuned MoO3) with better passivation properties, which accounts for the remarkable corrosion resistance improvement.

The erosion-enhanced corrosion behavior of electroless Ni–P coating was investigated by single particle impingement coupled with in-situ electrochemical measurements. The transient anodic dissolution of Ni–P coating induced by the single particle impingement is enhanced with the rising impact velocity, followed by a rapid repassivation that obeys a bi-exponential decaying law. The coating demonstrates a good erosion-corrosion resistance due to its strong capability of repassivation that is scarcely affected by the changing hydrodynamics under the test conditions. The erosion-enhanced corrosion rate of Ni–P coating in flowing slurry is well predicted based on the repassivation kinetic parameters determined from single particle impingement.

The corrosion behavior of J55 carbon steel pipe was investigated in a water production well environment in the Athabasca oil sands reservoir. The corrosion morphologies and the chemical compositions of corrosion products were examined by surface analysis techniques. The protection performance of the formed corrosion scales was evaluated using electrochemical measurements. The results show that severe erosion corrosion occurs on the inner wall of the pipe and causes a significant thinning, which is the dominant reason for the pipe failure. Likewise, the failure of the thread zone is originated from the severe corrosion of inner wall as well. Localized corrosion of carbon steel occurs in the welding zone because of the galvanic effect between stainless steel and carbon steel. Furthermore, the distributions of corrosion products on the inner wall are notably affected by the flow. Dense and thick Ca-containing corrosion scales act as a physical barrier layer and prevent the steel from further corrosion, whereas localized corrosion occurs in the regions with loose and thin corrosion scales.

Vascular endothelial cells produce reactive oxygen species (ROS) during the process of energy metabolism in aerobic respiration. A growing body of evidence indicates that excessive ROS is implicated in the pathogenesis of cardiovascular diseases including atherosclerosis. The newly synthesized halophenol, 2,4′,5′-trihydroxyl-5,2′-dibromo diphenylmethanone (TDD), exhibits antioxidative and cytoprotective activities in vitro. In this study, the protective effect of TDD against hydrogen peroxide (H2O2)-induced oxidative injury of EA.hy926 cells was investigated. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-dephenyltetrazolium bromide (MTT) assay, while the effect of TDD on the transcription profile of EA.hy926 cells subjected to H2O2-induced oxidative injury was evaluated by microarray analysis. Several signaling pathways, including apoptosis, were significantly associated with TDD. Flow cytometric analysis was used to evaluate anti-apoptotic effect of TDD. Subsequently, RT-PCR and Western blot were used to detect the expressions of the apoptosis-associated protein, Bcl-2 and Bax. Meanwhile the expression of cleaved caspase-3, an executioner of apoptosis, was also detected by Western blot. The results showed that pretreatment of EA.hy926 cells with TDD prevented the decrease of cell viability induced by H2O2, and attenuated H2O2-induced elevation of Bax and cleaved caspase-3 while increased Bcl-2 expressions. In summary, TDD inhibited H2O2-induced oxidative injury of EA.hy926 cells through negative regulation of apoptosis. These findings suggest that TDD is a potential candidate for therapeutic intervention in oxidative stress-associated cardiovascular diseases.

The role ofpHvalue and H2S concentration on the sulfide stress corrosion cracking of API 2205 duplex stainless steel was studied by means of slow strain-rate tests, polarization curve measurements and surface analysis. It was found that 2205 duplex stainless steel was highly susceptible to sulfide stress corrosion cracking aspHdecreased and H2S concentration increased. When thepHvalue was 2.8, the susceptibility stayed at a low level in 500 ppm H2S concentration but there existed a critical H2S concentration between 500 ppm and 1 000 ppm, above which the susceptibility rapidly increased. The sulfide stress corrosion cracking resulted from hydrogen-induced cracking and exhibited the characteristics of hydrogen embrittlement. The boundary of a phase and γ phase promoted the initiation of stress corrosion cracking, while γ phase inhibited its propagation.

Endothelial tight junction is a crucial intracellular junctional structure that controls paracellular permeability across vascular endothelium. Oxidative stress-mediated elevation in endothelial permeability is associated with pathogenesis of several cardiovascular diseases. In the present research, the regulation of farrerol on occludin, a transmembrane proteins associated with endothelial tight junction, was investigated in hydrogen peroxide-induced human endothelium-derived EA.hy926 cells. Western blot analysis demonstrated that H2O2 exposure caused a significant decrease in occludin expression, but had little effect on ZO-1 expression, and the decrease of occludin expression was significantly attenuated by farrerol in a dose-dependent manner. Meanwhile, immunofluorescent staining assay also demonstrated that the loss of occludin expression induced by H2O2 exposure was restored by farrerol pretreatment. Further investigations showed that farrerol prevented H2O2-induced activation of extracellular signal-regulated kinase (ERK) 1/2 in a dose-dependent manner. The use of U0126, a specific inhibitor of MEK1/2, proved that H2O2-induced decrease of occludin in EA.hy926 cells was likely associated with activation of ERK1/2, which indicated that the regulation of farrerol on occludin expression in H2O2-induced EA.hy926 cells was likely related to the modulation of ERK1/2 activation. In conclusion, the present study demonstrates for the first time that farrerol has potential effects on oxidative stress-induced endothelial tight junction disruption and suggests that farrerol is a potential candidate for the intervention of endothelial permeability-associated cardiovascular diseases.

A pH-controlled-release intelligent corrosion inhibitor is designed, which performs long-term inhibition capability in the solution. The pH-sensitive hydrogel was prepared via grafting the mixtures of acrylic acid (AA) and 2-hydroxy ethyl methacrylate (HEMA) onto potato starch backbones. Increasing pH generally produced an increased swelling of the hydrogel which peaked at pH 8.0. The hydrogel also showed a fast and reversible swelling behavior when alternately immersed in pH 1.0 and 8.0 solutions. A corrosion inhibitor, 1 H-Benzotriazole (BTA), was loaded into the hydrogels and the cumulative release capabilities were studied at different pH. From the electrochemical measurement and scanning electron microscopy (SEM) analysis, the intelligent corrosion inhibitor exhibited an improved long-term inhibition ability on aluminum alloy due to the controlled-release behaviors.

Stress corrosion cracking (SCC) behavior of X80 pipeline steel under the interference of various AC current densities was investigated in concentrated carbonate/bicarbonate solution by electrochemical measurements, immersion tests and slow strain rate tensile tests. A superimposed AC shifts the corrosion potential negatively and degrades the passivity of the steel. With the increase of AC current density, the corrosion rate of steel increases. At the short term effect of AC interference, the SCC cracks are intergranular and the SCC mechanism is anodic dissolution for steels with or without the application of AC. AC superimposition increases the SCC susceptibility of steel in carbonate/bicarbonate solution. The AC current density of 30A/m2is a critical value, above which the SCC susceptibility increases.

Four new limonoids (1-4), together with five known limonoids (5-9), were isolated from the fruits of Melia toosendan. Their structures were elucidated based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, IR, [α](D)). The isolated compounds were evaluated for their neurite outgrowth-promoting activities. Compounds 2 and 6 significantly enhanced NGF-mediated neurite outgrowth in PC12 cells at concentrations ranging from 0.1 to 50.0 μM.

Vascular endothelium plays an important role in the physiological homeostasis of blood vessels. Endothelial injury is considered to be implicated in the pathogenesis of many cardiovascular diseases, including atherosclerosis. Farrerol, a flavonoid considered to be the major bioactive component in a traditional Chinese herb, “Man-shan-hong”, which is the dried leaves of Rhododendron dauricum L., displays many bioactive properties, including antibechic, antibacterial, anti-inflammatory, and the inhibition of vascular smooth muscle cell (VSMC) proliferation. In this study, the protective effects of farrerol on hydrogen peroxide (H2O2)-induced apoptosis in human endothelium-derived EA.hy926 cells were investigated. The results showed that farrerol significantly inhibited the loss of cell viability and enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in H2O2-induced EA.hy926 cells. Meanwhile, farrerol inhibited H2O2-induced elevation in the levels of intracellular malondialdehyde and reactive oxygen species, as well as cell apoptosis. Furthermore, real time RT–PCR and Western blot analysis showed that farrerol significantly decreased the expression of Bax mRNA, Bax, cleaved caspase-3, and phosph-p38 MAPK, while increasing the exporession of Bcl-2 mRNA and Bcl-2 in H2O2-induced EA.hy926 cells. These results are the first demonstration that farrerol has protective effects against H2O2-induced apoptosis in EA.hy926 cells, and suggests that farrerol is a potential candidate for the intervention of endothelial-injury-associated cardiovascular diseases.

The bioassay-oriented fractionation of mistletoe crude extracts (MCEE) using 75% ethanol and culture products of mistletoe transformed by Rhodobacter sphaeroides, a photosynthetic bacterium (PSBT), revealed that the high cytotoxic activities were due to the petroleum ether extracts (PEs) and the acid-precipitated proteins from the aqueous extracts (AQs) of MCEE and PSBT. The isolated triterpenes may account for the activities of the PEs of MCEE and PSBT, respectively. Extraction of MCEE using petroleum ether led to the isolation of 3-epi-betulinic acid (1), betulonic acid (2), oleanolic acid (3), and beta-amyrin acetate (4), while petroleum ether extraction of PSBT led to the isolation of 1,3,4,betulinic acid (5), erythrodiol (6), and (3beta)-olean-12-ene-3,23-diol (7). The PE of PSBT exerted higher cytotoxicity than the PE of MCEE, which was due to the different triterpene contents of these two extracts. The cytotoxic activities of all compounds were tested, and the results revealed that compounds 1, 2, 3, 5, 6, and 7 contributed significantly to the cytotoxicities of both PEs. The AQ of the PSBT exerted almost the same cytotoxic activity and lower toxicity compared to the AQ of the MCEE. These findings indicate that mistletoe products biotransformed by R. sphaeroides could be used to treat cancers, since they have lower toxicities and higher antitumor activities compared to standard treatments.

Endothelial injury has been implicated in the pathogenesis of many cardiovascular diseases, including thrombotic disorders. Hyperin (quercetin-3-O-galactoside), a flavonoid compound and major bioactive component of the medicinal herb Apocynum venetum L., is commonly used to prevent endothelium dysfunction. However, its mode of action remains unclear. To the best of our knowledge, we have for the first time investigated the protective effect hyperin exerts against H2O2-induced injury in human endothelium-derived EA.hy926 cells using isobaric tags for relative and absolute quantitation (iTRAQ)‑based quantitative proteomic analysis. The results showed that H2O2 exposure induced alterations in the expression of 250 proteins in the cells. We noted that the expression of 52 proteins associated with processes such as cell apoptosis, cell cycle and cytoskeleton organization, was restored by hyperin treatment. Of the proteins differentially regulated following H2O2 stress, the anti-apoptotic protein, myeloid cell leukemia-1 (Mcl-1), and the pro-apoptotic protein, BH3-interacting domain death agonist (Bid), exhibited marked changes in expression. Hyperin increased Mcl-1 expression and decreased that of Bid in a dose-dependent manner. In addition, flow cytometric analysis and western blot analysis of the apoptosis-related proteins, truncated BID (tBid), cleaved caspase-3, cleaved caspase-9, Fas, FasL and caspase-8, demonstrated that the rate of apoptosis and the pro-apoptotic protein levels were decreased by hyperin pre‑treatment. In the present study we demonstrate that hyperin effectively prevents H2O2‑induced cell injury by regulating the Mcl‑1‑ and Bid-mediated anti‑apoptotic mechanism, suggesting that hyperin is a potential candidate for use in the treatment of thrombotic diseases.

A new activator was proposed to evaluate the susceptibility of type 304L stainless steel to intergranular corrosion using the electrochemical potentiodynamic reactivation (EPR) technique. ...

Oxidative stress plays a critical role in endothelial injury and the pathogenesis of diverse cardiovascular diseases, including atherosclerosis. Isoquercitrin (quercetin-3-glucoside), a flavonoid distributed widely in plants, exhibits many biological activities, including anti-allergic, anti-viral, anti-inflammatory, and anti-oxidative effects. In the present study, the inhibitory effect of isoquercitrin on H2O2-induced apoptosis of EA.hy926 cells was evaluated. MTT assays showed that isoquercitrin significantly inhibited H2O2-induced loss of viability in EA.hy926 cells. Hoechst33342/PI and Annexin V-FITC/PI fluorescent double staining indicated that isoquercitrin inhibited H2O2-induced apoptosis of EA.hy926 cells. Western blotting demonstrated that isoquercitrin prevented H2O2-induced increases in cleaved caspase-9 and cleaved caspase-3 expression, while increasing expression of anti-apoptotic protein Mcl-1. Additionally, isoquercitrin significantly increased the expression of p-Akt and p-GSK3β in a dose-dependent manner in EA.hy926 cells. LY294002, a PI3K/Akt inhibitor, inhibited isoquercitrin-induced GSK3β phosphorylation and increase of Mcl-1 expression, which indicated that regulation of isoquercitrin on Mcl-1 expression was likely related to the modulation of Akt activation. These results demonstrated that the anti-apoptotic effect of isoquercitrin on H2O2-induced EA.hy926 cells was likely associated with the regulation of isoquercitrin on Akt/GSK3β signaling pathway and that isoquercitrin could be used clinically to interfere with the progression of endothelial injury-associated cardiovascular disease.

Andrographolide is widely used in clinic as an anti-inflammatory and antibiotic drug. In this paper, the metabolites of andrographolide in rats after single oral doses of 120 mg/kg were investigated. The structures of the metabolites were elucidated by high-resolution mass spectra, NMR spectroscopy including 1H NMR, 13C NMR, and two-dimensional NMR, through comparison to a synthetic standard. The main metabolite of andrographolide in rats was 14-deoxy-12(R)-sulfo andrographolide. In the proposed mechanism, the β-carbon of α, β-unsaturated carbonyl was attacked by sulfonic acid, to form the sulfonate compound. This was a rare metabolic reaction. It may be the main metabolic pathway of andrographolide in rats. The polarity of the sulfonate metabolite increased greatly and could be easily eliminated from body.

The microbial transformation of beta-amyrin acetate (compound 1) occurred in the culture of Rhodobacter sphaeroides producing three metabolites. The metabolites were purified and identified as beta-amyrin (compound 2), (3beta)-olean-12-ene-3, 23-diol (compound 3), and erythrodiol (compound 4). Initially, it was found that beta-amyrin acetate could be deacetylated and hydroxylated by microbial methods.

Six new andrographolide metabolites M-5-M-10 were isolated from rat urine, feces, and the contents of the small intestine. Three (M-5-M-7) as sulfate ester compounds were identified as new compounds. The structures of these six metabolites were determined to be 14-deoxy-12(R)-sulfo andrographolide 3-sulfate (M-5), 14-deoxy-12(S)-sulfo andrographolide 3-sulfate (M-6), 14-sulfo isoandrographolide 3-sulfate (M-7), 14-deoxy-11,12-didehydroandrographolide (M-8), isoandrographolide (M-9), and 14-deoxy andrographolide (M-10), respectively, based on chemical evidence and spectroscopic analysis.

X80 pipeline steel is a low carbon, micro–alloyed high–grade steel and a fairly new steel used as pipeline material in worldwide. The material has the huge potential to be used widely for building the oil/gas transmission pipelines in the 21st century because of its high intensity and high toughness. X80 steel has been adopted on the second west–east gas transmission pipeline project in China. Whereas, there is a issue, stress corrosion cracking (SCC) is more likely to occur on X80 pipeline steel, because of its high strength and fine microstructure, it will be a vital threat to safe operation of buried oil/gas pipelines. However, the related research about SCC behavior of X80 pipeline steel in high pH carbonate/bicarbonate solution is rarely reported at present. Comparing with X65 pipeline steel, X80 steel has higher strength and finer microstructure, because of these differences, it may have some certain influence on the SCC behavior of X80 steel, and even change the mechanism of high pH SCC. Consequently, it is necessary to study the SCC behavior and mechanism of X80 steel in high pH solution. In this work, the SCC behavior and mechanism of X65 and X80 pipeline steels in high pH concentrated carbonate/bicarbonate solution are investigated by slow strain rate testing (SSRT), electrochemical test and surface analysis technique. The results show that the cracking mode of X65 pipeline steel in carbonate/bicarbonate solution is intergranular SCC (IGSCC). While the mixed cracking mode of X80 pipeline steel in high pH solution is that the crack is intergranular in the early stage of the crack propagation, and transgranular SCC (TGSCC) in the later stage, which is mainly * 6r=$/=\ *v 51131001 B6r!n^B oQ*v 2012AA040105 :5 X^=#* : 2013–06–08, X^6 #* : 2013–09–07 B z : 0 m, y, 1985 ~?, !Q? DOI: 10.3724/SP.J.1037.2013.00315 j 12 / le : X65 A X80 /$ pH +U%bdI F(U2 f^C 1591 transgranular. The cracking mode of X80 steel is associated with the microstructure and high strength of the steel. The key reason for TGSCC occurring of X80 steel is that the decrease of pH value of the crack tip during the crack propagation process. The SCC mechanism of X65 steel in high pH carbonate/bicarbonate solution is anodic dissolution (AD) mechanism. While the SCC mechanism of X80 steel in high pH solution is mixed controlled by both AD and hydrogen embrittlement (HE) mechanisms, and the HE mechanism may play a significant role in the deep crack propagation at the later stage. The high strength X80 steel consisted of fine acicular ferrite and granular bainite has a higher susceptibility to SCC in high pH solution, comparing with low strength X65 steel composed of ferrite and pearlite.