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Eight new caffeoyl derivatives, elephantomentosides A–H (1 − 8), together with ten known ones (9 − 18), were isolated from the whole plant of Elephantopos tomentosus L. Their structures were elucidated using detailed spectroscopic analysis. Structurally, compounds 1 − 8 are composed of β-D-glucopyranose, and almost all of the substituent positions are at the C-1′ and C-4′ of glucopyranose. The anti-inflammatory and antioxidant activities of all isolated compounds were evaluated in vitro. Compounds 9–10, 13–15, and 17–18 exhibited significant DPPH scavenging capacity with IC50 values in the range of 10.01–25.07 μM, in comparison with Vc (IC50, 17.98 μM). [ABSTRACT FROM AUTHOR]

Nucleotides and their derivatives are vital biomarkers that play essential roles in biochemical reactions and influence processes of metabolism and anabolism. However, discriminating between various structurally similar nucleotides and their phosphate derivatives using convenient means still poses a challenge. Here, we designed a supramolecular fluorescence sensor array constructed with four different calixarenes loaded with dyes to discriminate between nucleotides and their phosphate derivatives. Based on the differences in the ability of calixarenes to recognise various nucleotides and nucleotide phosphates, a unique fluorescence response pattern is generated for each analyte. With the assistance of linear discriminant analysis, the discrimination of target analytes is effectively achieved. Subsequent assays involving various concentrations of nucleoside triphosphates and mixtures of nucleotide phosphates have also verified the potential of this sensor array based on calixarenes in the investigation of nucleotides. [ABSTRACT FROM AUTHOR]

Scutellaria baicalensis Georgi (Labiatae) (“huang qin”), Ligusticum chuanxiong Hort. (Umbelliferae) (“chuang xiong”), Panax notoginseng (Burk.) F.H. Chen (Araliaceae) (“san qi”), Uncaria rhynchophylla (Miq.) Jackson. (Rubiaceae) (“gou teng”), Rhokiola rosea L. (Crassulaceae) (“hong jing tian”) and Stephania tetrandra S. Moore (Menispermaceae) (“fang ji”) are commonly used traditional Chinese medicine (TCM) for hypertensive patients. The pharmacologically active compounds found in these TCMs are baicalin, ligustrazine, notoginsenoside R1, rhynchophylline, salidroside and tetrandrine, respectively, which possess antihypertensive properties with diverse cellular mechanisms. In this study, we attempted to evaluate a possible correlation of the antioxidative activities (using the DPPH assay) and the vaso-relaxation effects (using rat isolated thoracic aorta) of these compounds. In the antioxidative study, a relative order of free radical scavenging capacity (SR%) of baicalin ≥ tetradrine >> salidroside ≥ ligustrazine ≥ rhynchophylline ≈ notoginsenoside R1 was demonstrated. In the vaso-relaxing study, a relative order of the maximum relaxation response (at 3 mM) of tetradrine > baicalin >> ligustrazine > notoginsenoside R1 ≈ rhynchophylline > salidroside was recorded. A positive correlation (R2 = 0.7741) between the antioxidative activity and the vascular relaxation effect of the compounds evaluated was illustrated. In contrast, ascorbic acid only elicited a free radical scavenging activity with no apparent relaxation effect, whereas nifedipine (a Ca2+ channel blocker) caused a marked vascular relaxation with no obvious free radical scavenging activity. Hence, our results suggest, for the first time, that the therapeutic effect (e.g., antihypertensive) of these TCM-oriented drugs, unlike western medicine, are probably correlated with the unique antioxidative potential of these compounds. [ABSTRACT FROM AUTHOR]

A facile method, based on high performance liquid chromatography (HPLC) with diode array detection (DAD), was developed for the simultaneous quantitative determination of nine xanthones in the root of Polygala caudata Rehd. et Wils., a Chinese folk medicinal herb. The HPLC fingerprint of xanthones was developed for the first time and applied to assess the quality of related Polygala medicinal plants. Ultrasonic extraction with chloroform‐methanol (98∶2) gave good yields of nine xanthone standards, the average recovery rates ranged from 94.1 to 113.4% (n=5). The relative standard deviation (RSD) values for reproducibility were between 2.21 and 9.21% (n=5). The fingerprint chromatograms of P. tenuifolia Wild. from six different planting regions were analyzed to set up a simulative mean chromatogram with 11 common peaks. The software of Similarity Evaluation System for Chromatographic Fingerprint of TCM (2004A version), developed by Chinese Pharmacopoeia Commission, was applied for data processing. The correlation coefficients of each chromatogram to the simulative mean chromatogram of P. tenuifolia were within the range of 0.807∼⃒0.927, and the correlation coefficients between each chromatogram were 0.689∼⃒0.907. The method can be used for the quality evaluation and control of Radix Polygalae, and provide a possibility for identifying the Polygala species rapidly. [ABSTRACT FROM AUTHOR]

Thalictrum (Ranunculaceae) is an extremely abundant medicinal plant source. Due to their marked ethnopharmacological usages in folk medicine of China and the large number of potentially active chemical constituents, they may be a rich source for new chemicals for drug R&D. Here, an investigation on traditional functions and folk therapeutic uses of Thalictrum plants from China, as well as their main chemical constituents, was undertaken. It showed that 43 Thalictrum plants have long been used as folk medicine to treat many diseases in different races of China. In addition, the correlation between folk therapeutic effects and chemical constituents, and the modern pharmacological activities, are discussed as well as the prospect of isolation and development of new drugs from this genus of plants. [ABSTRACT FROM AUTHOR]

With the development of sequencing technology, more and more rare thalassemia types have been found. In this article, we found a novel Hb H disease combined with glucose-6-phosphate dehydrogenase (G6PD) deficiency through whole genome sequencing (WGS), which was verified by Sanger sequencing and polymerase chain reaction (PCR)-reverse dot-blot hybridization, respectively. [ABSTRACT FROM AUTHOR]

This article presents standards commonly used for microgrid technology and practical tests of these standards before developing an industry microgrid standard. Standards of communication networks, Internet security, data and communications security, installation and protection of distributed generators and energy storage devices, electronic power interfaces of distributed energy resources, and interconnection of microgrids to electric power system are analyzed. The practical tests for the above standards are planned to perform at a low-voltage (380-V) AC microgrid test bed built by the Institute of Nuclear Energy Research, Taiwan. Microgrid configurations, installation of distributed generators and energy storage systems, operation conditions of the microgrid, microgrid energy management and control systems, and microgrid protection are mentioned in the proposed standard tests. The main contributions of this article are (i) to review and analyze common standards used for microgrids, (ii) to present research works from Taiwan to develop a microgrid standard for industry applications, and (iii) to propose practical tests of critical standards used for microgrids and how to perform these tests at a real-time low-voltage AC microgrid in Taiwan. [ABSTRACT FROM AUTHOR]

A high performance liquid chromatographic method was developed and applied to the simultaneous determination of puerarin and danshensu in a traditional Chinese medicinal preparation containing Pueraria lobata and Salvia miltiorrhiza as its major herbal constituents. Elution was performed on a C18 column at 27°C with acetonitrile-water (0.5% acetic acid) at different proportions according to a time scheduled programme, and pumped at a flow rate of 1.0 mL/min. Indomethacin was used as an internal standard. High resolution was obtained between the analytes and the internal standard. The intra-day and inter-day precisions were better than 1.9% and 2.2%, respectively. The coefficient of determination for each analyte was above 0.997. It is a simple and sensitive analytical method with good accuracy and reproducibility. [ABSTRACT FROM AUTHOR]

A simple and reliable method of ultra-performance liquid chromatography coupled with a photodiode array detector (UPLC-PAD) was developed for the quantitative analysis of 10 active nucleosides and nucleobases. The separation was performed on a reversed-phase C18 column with linear gradient elution. This method provided good reproducibility and sensitivity with excellent intra- and inter-day precision and the validated method was successfully used for the determination of the 10 components of interest of F. unibracteata samples. The quantitative data of the fingerprints were analyzed by similarity analysis (SA) and hierarchical clustering analysis (HCA). Results showed that samples from different regions could be successfully divided into two groups in accordance with their locations of origin. A rapid and convenient discriminatory function using UPLC fingerprint combined with HCA was then established to differentiate the F. unibracteata from different growing regions, which could be helpful for quality evaluation and control of F. unibracteata and related medicinal plants in the future. [ABSTRACT FROM AUTHOR]

Two new xanthone O-glycosides, polyhongkongenosides A (1) and B (2), together with four known xanthone glycosides, were isolated from the herbs of Polygala hongkongensis Hemsl. Their structures were elucidated on the basis of UV, IR, NMR, and MS spectral data. The antioxidant in vitro activities of 1-6 were determined by the scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and hydroxyl radicals and their reductive activities to Fe3 + . Mangiferin, one of the four known xanthone glycosides, showed potential scavenging effect on DPPH and hydroxy radicals and reductive activity to Fe3 + with IC50 values of 4.7, 13.9, 23.7 μM, respectively. [ABSTRACT FROM AUTHOR]

Puerarin (1) is a major effective ingredient extracted from the traditional Chinese medicine Ge-gen (Radix Puerariae, RP). Recently, puerarin has been used to treat patients with coronary artery diseases (CAD). However, the mechanisms of puerarin on CAD are still not very clear. In this study, we investigated the role of puerarin on serum nitric oxide (NO) concentration, myocardial endothelial nitric oxide synthase (eNOS) gene expression, the protein expression of eNOS and inducible nitric oxide synthase (iNOS), as well as the level of protein kinase B (Akt/PKB) phosphorylation in rats with myocardial infarction. We found that puerarin (120 mg/kg/day, i.p.) could increase serum nitrite concentration in rat with myocardial ischemia (MI). It also induced the gene expression or activation of eNOS, protein expression of eNOS, and the Akt/PKB phosphorylation. From these results, we suggested that puerarin could increase serum nitric oxide level of rat with myocardial infarction, which should be one of the mechanisms of the therapeutic effect of puerarin on CAD. The increased expression of eNOS and the Akt/PKB pathway may be the underlying mechanism by which puerarin stimulates NO production. [ABSTRACT FROM AUTHOR]