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Traditional Tibetan medicine (TTM) has been valuable for the identification of new therapeutic leads. Nevertheless, reports about the chemical constituents of TTM are meager owing to the lack of suitable purification techniques. In this study, an off-line two-dimensional reversed-phase/hydrophilic interaction liquid chromatography (2D RP/HILIC) technique guided by on-line HPLC-DPPH has been established for the isolation of pure antioxidants from the extract of Dracocephalum heterophyllum . According to the chromatographic recognition outcome of the HPLC-DPPH system, the first-dimensional (1D) separation on the Megress C18 preparative column yielded 6 antioxidative fractions (61.4% recovery) from the ethyl acetate fraction (6.1 g). In the second-dimensional (2D) separation, a HILIC XAmide preparative column was employed. In total, 8 antioxidants were isolated from D. heterophyllum with a purity of >95%, which indicated the efficiency of the developed method to prepare antioxidative compounds with high purity from plant extracts. In addition, this method was highly efficient for the preparation of structural analogues of the antioxidative polyphenols and could be applied for the purification of structural analogues from other resources. [ABSTRACT FROM AUTHOR]

An offline preparative two-dimensional reversed-phase liquid chromatography/hydrophilic interaction liquid chromatography coupled with hydrophilic interaction solid-phase extraction method was developed for the preparative isolation of flavonoid glycosides from a crude sample of Sphaerophysa salsula. First, the non-flavonoids were removed using an XAmide solid-phase extraction cartridge. Based on the separation results of three different chromatographic stationary phases, the first-dimensional preparation was performed on an XAqua C18 prep column, and 15 fractions were obtained from the 5.2 g target sample. Then, three representative fractions were selected for additional purification on an XAmide preparative column to further isolate the flavonoid glycosides. In all, eight flavonoid glycosides were isolated in purities over 97%. The results demonstrated that the two-dimensional liquid chromatography method used in this study was effective for the preparative separation of flavonoid glycosides from Sphaerophysa salsula. Additionally, this method showed great potential for the separation of flavonoid glycosides from other plant materials.

Herbal plants are significant for the reason that they have a great potential in discovering drug precursors. However, how to purify compounds with higher purity from them is a question which needs to be discussed. In present study, an offline 2D reversed-phase (RP) preparative liquid chromatography coupled with solid-phase extraction (SPE) method was successfully developed for the separation of flavonolignan diastereoisomers from Arenaria kansuensis. Based on the analysis of results, the major conclusion that we have drawn from it is a RP-SPE was selected for enriching target flavonolignan sample from A. kansuensis. After that, an ODS preparative column was used for 1D preparation, and the target sample (4.6 g) was divided into five fractions with a recovery of 83.9%. Then, a C18HCE preparative column, a polar-modified RP (polar-copolymerized) type, was used for isolating flavonolignan diastereoisomers in the 2D preparation. By establishing optimal 2D chromatography, hydrophilic interaction chromatography (HILIC) columns and normal-phase (NP) columns were tested simultaneously, and the result showed that diastereoisomers are not suitable for HILIC and NP chromatography mode. Our study resulted in a tricin and five analogous derivative flavonolignans with purity >98% were successfully purified from A. kansuensis. This is the initial report of Salcolin C, Salcolin B, Tricin 4'-O-(C-veratroylglycol) ether and 5'-methoxyhydnocarpin D from A. kansuensis. In addition, it tended to be the first time that Tricin 4'-O-(C-veratroylglycol) ether is isolated from natural resource. This method has great potential for efficiently isolating flavonolignan diastereoisomers from A. kansuensis, and it shows a great prospect for the separation of flavonolignans from complex samples.

Herbal plants are significant for the reason that they have a great potential in discovering drug precursors. However, how to purify compounds with higher purity from them is a question which needs to be discussed. In present study, an offline 2D reversed-phase (RP) preparative liquid chromatography coupled with solid-phase extraction (SPE) method was successfully developed for the separation of flavonolignan diastereoisomers from Arenaria kansuensis. Based on the analysis of results, the major conclusion that we have drawn from it is a RP-SPE was selected for enriching target flavonolignan sample from A. kansuensis. After that, an ODS preparative column was used for 1D preparation, and the target sample (4.6 g) was divided into five fractions with a recovery of 83.9%. Then, a C18HCE preparative column, a polar-modified RP (polar-copolymerized) type, was used for isolating flavonolignan diastereoisomers in the 2D preparation. By establishing optimal 2D chromatography, hydrophilic interaction chromatography (HILIC) columns and normal-phase (NP) columns were tested simultaneously, and the result showed that diastereoisomers are not suitable for HILIC and NP chromatography mode. Our study resulted in a tricin and five analogous derivative flavonolignans with purity >98% were successfully purified from A. kansuensis. This is the initial report of Salcolin C, Salcolin B, Tricin 4'-O-(C-veratroylglycol) ether and 5'-methoxyhydnocarpin D from A. kansuensis. In addition, it tended to be the first time that Tricin 4'-O-(C-veratroylglycol) ether is isolated from natural resource. This method has great potential for efficiently isolating flavonolignan diastereoisomers from A. kansuensis, and it shows a great prospect for the separation of flavonolignans from complex samples.

The pathogenesis of itchy skin diseases including allergic contact dermatitis (ACD) is complicated and the treatment of chronic itch is a worldwide problem. One traditional Tibetan medicine, Qingpeng ointment (QP), has been used in treatment of ACD in China for years. In this study we used HPLC and LC/MS analysis, combined with a BATMAN-TCM platform, for detailed HPLC fingerprint analysis and network pharmacology of QP, and investigated the anti-inflammatory and antipruritic activities of QP on ACD induced by squaric acid dibutylester (SADBE) in mice. The BATMAN-TCM analysis provided information of effector molecules of the main ingredients of QP, and possible chronic dermatitis-associated molecules and cell signaling pathways by QP. In ACD mice, QP treatment suppressed the scratching behavior induced by SADBE in a dose-dependent manner and inhibited the production of Th1/2 cytokines in serum and spleen. Also, QP treatment reversed the upregulation of mRNAs levels of itch-related genes in the skin (TRPV4, TSLP, GRP, and MrgprA3) and DRGs (TRPV1, TRPA1, GRP, and MrgprA3). Furthermore, QP suppressed the phosphorylation of Erk and p38 in the skin. In all, our work indicated that QP can significantly attenuate the pathological alterations of Th1/2 cytokines and itch-related mediators, and inhibit the phosphorylation of MAPKs to treat the chronic itch.

The pathogenesis of itchy skin diseases including allergic contact dermatitis (ACD) is complicated and the treatment of chronic itch is a worldwide problem. One traditional Tibetan medicine, Qingpeng ointment (QP), has been used in treatment of ACD in China for years. In this study we used HPLC and LC/MS analysis, combined with a BATMAN-TCM platform, for detailed HPLC fingerprint analysis and network pharmacology of QP, and investigated the anti-inflammatory and antipruritic activities of QP on ACD induced by squaric acid dibutylester (SADBE) in mice. The BATMAN-TCM analysis provided information of effector molecules of the main ingredients of QP, and possible chronic dermatitis-associated molecules and cell signaling pathways by QP. In ACD mice, QP treatment suppressed the scratching behavior induced by SADBE in a dose-dependent manner and inhibited the production of Th1/2 cytokines in serum and spleen. Also, QP treatment reversed the upregulation of mRNAs levels of itch-related genes in the skin (TRPV4, TSLP, GRP, and MrgprA3) and DRGs (TRPV1, TRPA1, GRP, and MrgprA3). Furthermore, QP suppressed the phosphorylation of Erk and p38 in the skin. In all, our work indicated that QP can significantly attenuate the pathological alterations of Th1/2 cytokines and itch-related mediators, and inhibit the phosphorylation of MAPKs to treat the chronic itch.

In the present study, nine compounds (1-9) were isolated from Colletotrichum gloeosporioides (an endophytic fungus from Uncaria rhynchophylla) which was cultured in wheat bran medium. Their structures were elucidated as 4-Epi-14-hydroxy-10, 23-dihydro-24, 25-dehydroaflavinine (1), 10, 23-Dihydro-24,25 -dehydro-21-oxoaflavinine (2), Ergosterol (3), Ergosterol peroxide (4), Mellein (5), 4, 5-dihydroblumenol A (6), Colletotrichine A (7), Cyclo(L-leucyl-L-leucyl) (8), and Brevianamide F (9) based on NMR spectral data, as well as comparing with previous literature data. This is the first report about the isolation of compounds 1-2, 6, and 8-9 from Colletotrichum genus. All compounds were tested for their phosphoinositide 3-kinase (PI3Kα) inhibitory activity. Compounds 8 and 9 showed potent PI3K α inhibitory activity with IC50 values of 38.1 and 4.8 µM, respectively, while the other compounds showed very weak activity at a concentration of 20 µg/mL.

Five phenylethanoid glycosides (PhGs), forsythoside B, verbascoside, alyssonoside, isoverbascoside, and leucosceptoside B, were isolated and purified from Lamiophlomis rotata (Benth.) Kudo by high-speed counter-current chromatography (HSCCC) combined with macroporous resin (MR) column separation. In the present study, the two-phase solvent system composed of ethyl acetate/n-butanol/water (13:3:10, v/v/v) was used for HSCCC separation. A total of 27 mg of forsythoside B, 41 mg of verbascoside, 29 mg of alyssonoside, 23 mg of isoverbascoside, and 13 mg of leucosceptoside B with purities of 97.7, 99.2, 99.5, 99.3, and 97.3%, respectively, were obtained in a one-step separation within 4 h from 150 mg of crude extract. The recoveries of the five PhGs after MR-HSCCC separation were 74.5, 76.5, 72.5, 76.4, and 77.0%, respectively. The chemical structures of all five compounds were identified by (1) H and (13) C NMR spectroscopy.

Five phenylethanoid glycosides (PhGs), forsythoside B, verbascoside, alyssonoside, isoverbascoside, and leucosceptoside B, were isolated and purified from Lamiophlomis rotata (Benth.) Kudo by high-speed counter-current chromatography (HSCCC) combined with macroporous resin (MR) column separation. In the present study, the two-phase solvent system composed of ethyl acetate/n-butanol/water (13:3:10, v/v/v) was used for HSCCC separation. A total of 27 mg of forsythoside B, 41 mg of verbascoside, 29 mg of alyssonoside, 23 mg of isoverbascoside, and 13 mg of leucosceptoside B with purities of 97.7, 99.2, 99.5, 99.3, and 97.3%, respectively, were obtained in a one-step separation within 4 h from 150 mg of crude extract. The recoveries of the five PhGs after MR-HSCCC separation were 74.5, 76.5, 72.5, 76.4, and 77.0%, respectively. The chemical structures of all five compounds were identified by (1) H and (13) C NMR spectroscopy.

A new flavonoid, along with 16 known ones, was separated from the aerial parts of Asterothamnus centrali-asiaticus. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR techniques and HRESIMS. To confirm the structure of the new compound, computational prediction of its 13C chemical shifts was performed. All of the 17 flavonoids were reported from A. centrali-asiaticus for the first time. In addition, all flavonoids were evaluated for their antioxidant and α-glucosidase inhibitory activities. The results showed that 10 of them exhibited antioxidant activity. Meanwhile, four flavonoids displayed α-glucosidase inhibitory effect with IC50 values ranging from 38.9 to 299.7 μM.

A new flavonoid, along with 16 known ones, was separated from the aerial parts of Asterothamnus centrali-asiaticus. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR techniques and HRESIMS. To confirm the structure of the new compound, computational prediction of its 13C chemical shifts was performed. All of the 17 flavonoids were reported from A. centrali-asiaticus for the first time. In addition, all flavonoids were evaluated for their antioxidant and α-glucosidase inhibitory activities. The results showed that 10 of them exhibited antioxidant activity. Meanwhile, four flavonoids displayed α-glucosidase inhibitory effect with IC50 values ranging from 38.9 to 299.7 μM.

This study presents an efficient strategy for separation of three phenolic compounds with high molecular weight from the crude extract of Terminalia chebula Retz. by ultrasound-assisted extraction and high-speed counter-current chromatography. The ultrasound-assisted extraction conditions were optimized by response surface methodology and the results showed the target compounds could be well enriched under the optimized extraction conditions. Then the crude extract was directly separated by high-speed counter-current chromatography without any pretreatment using n-hexane/ethyl acetate/methanol/water (1:7:0.5:3, v/v/v/v) as the solvent system. In 180 min, 13 mg of A, 18 mg of B, and 9 mg of C were obtained from 200 mg of crude sample. Their structures were identified as Chebulagic acid (A, 954 Da), Chebulinic acid (B, 956 Da), and Ellagic acid (C) by (1) H NMR spectroscopy.

The method of capillary zone electrophoresis (CZE) with direct UV detection was developed for the determination of oleanolic acid, ursolic acid, quercetin and apigenin. and then for the first time successfully applied to the analysis of four analytes in <i>Swertia mussotii</i> Franch and its preparations. Various factors affecting the CZE procedure were investigated and optimized, and the optimal conditions were: 50 × 10<sup>−3</sup> mol/L borate-phosphate buffer (pH 9.5) with 5.0 × 10<sup>−3</sup> mol/L <i>β</i>-cyclodextrin, 15 kV separation voltage, 20 °C column temperature, 250 nm detection wavelength and 5 s electrokinetic injection time (voltage 20 psi). Under the conditions, oleanolic acid, ursolic acid, quercetin and apigenin could be determined within the test ranges with a good correlation coefficient (<i>r</i>² > 0.9991). The limits of detection for conditions, oleanolic acid, ursolic acid, quercetin and apigenin were 0.3415, 0.2003, 0.0062 and 0.2538 µg/mL, respectively, and the intra- and inter-day relative standard deviations were no more than 4.72%. This procedure provided a convenient, sensitive and accurate method for simultaneous determination of oleanolic acid, ursolic acid, quercetin and apigenin in <i>S. mussotii</i> Franch. Copyright © 2014 John Wiley & Sons, Ltd.

This study is to develop an UPLC-PDA method for determination of 10 major components in Pterocephalus. The UPLC-PDA assay was performed on a Waters Acquity UPLCR BEH C₁₈(2.1 mm ×100 mm,1.7 μm), and the column temperature was at 30 ℃. The mobile phase consists of water containing 0.2% phosphoric acid (A) and acetonitrile (B) in gradient elution at a flow rate of 0.4 mL•min⁻¹. The detection wave length was set at 237 and 325 nm, and the injection volume was 1 μL in the UPLC system. The linear range of 10 detected compounds were good (r≥0.999 7), and the overall recoveries ranged from 96.30% to 103.0%, with the RSD ranging from 0.72% to 2.9%. The method was simple, accurate and reproducible, which can be used for the simultaneous determination of the content of ten major components in P. hookeri.

An imbalance in osteogenesis and osteoclastogenesis is a crucial pathological factor in the development of osteoporosis. Osteoclasts (OCs) play a pivotal role in osteoporosis, whose new therapy exploration has been focused on the suppression of OC formation. Sophoridine is found from the Chinese traditional food sophora flower to exhibit anti-osteoporosis capacity by screening. This study is focused on its anti-osteoporosis mechanism evaluation. The anti-osteoporosis effect of sophoridine, (15 mg kg-1 body), was evaluated in ovariectomized (OVX) mice by monitoring changes in bone histomorphometry index, formation of osteoclasts from blood-derived mononuclear cells, and changes in the synthesis of pro-osteoclastogenic cytokines. Signal pathways were investigated by QPCR, Western blot, and immunofluorescence. Sophoridine has a significant anti-osteoporosis effect in vivo, which can inhibit RANKL-induced OC formation, the appearance of OC-specific marker genes, and OC marker protein in vitro. Mechanistically, sophoridine dose- and time-dependently blocks the RANKL-induced OC formation and the activation of ERK and c-Fos as well as the induction and nucleus translocation of NFATc1. Sophora flower might be a useful alternative functional food in preventing or treating osteoporosis.

Context: Standardized myrtol, an essential oil containing primarily cineole, limonene and α-pinene, has been used for treating nasosinusitis, bronchitis and chronic obstructive pulmonary disease (COPD).Objective: To investigate the effects of standardized myrtol in a model of acute lung injury (ALI) induced by lipopolysaccharides (LPS).Materials and methods: Male BALB/c mice were treated with standardized myrtol for 1.5 h prior to exposure of atomized LPS. Six hours after LPS challenge, lung injury was determined by the neutrophil recruitment, cytokine levels and total protein concentration in the bronchoalveolar lavage fluid (BALF) and myeloperoxidase (MPO) activity in the lung tissue. Additionally, pathological changes and NF-κB activation in the lung were examined by haematoxylin and eosin staining and western blot, respectively.Results: In LPS-challenged mice, standardized myrtol at a dose of 1200 mg/kg significantly inhibited the neutrophile counts (from 820.97 ± 142.44 to 280.42 ± 65.45, 103/mL), protein concentration (from 0.331 ± 0.02 to 0.183 ± 0.01, mg/mL) and inflammatory cytokines level (TNF-α: from 6072.70 ± 748.40 to 2317.70 ± 500.14, ng/mL; IL-6: from 1184.85 ± 143.58 to 509.57 ± 133.03, ng/mL) in BALF. Standardized myrtol also attenuated LPS-induced MPO activity (from 0.82 ± 0.04 to 0.48 ± 0.06, U/g) and pathological changes (lung injury score: from 11.67 ± 0.33 to 7.83 ± 0.79) in the lung. Further study demonstrated that standardized myrtol prevented LPS-induced NF-κB activation in lung tissues.Discussion and conclusion: Together, these data suggest that standardized myrtol has the potential to protect against LPS-induced airway inflammation in a model of ALI.

BACKGROUND: Potentilla fruticosa, also called "Jinlaomei" and "Gesanghua", is widely used as folk herbs in traditional Tibetan medicine in China to treat inflammations, wounds, certain forms of cancer, diarrhoea, diabetes and other ailments. Previous research found P. fruticosa leaf extract (C-3) combined with Ginkgo biloba extracts (EGb) showed obvious synergistic effects in a variety of oxidation systems. The aim of the present study was to further confirm the synergy of P. fruticosa combined with EGb viewed from physiological bioavailability and explore the related bioactive mechanism behind the synergism.METHODS: The microbial test system (MTS) was adopted to evaluate the related bioactive mechanism. The synergistic effects were evaluated by isobolographic analysis. The H2O2 production rate and antioxidant enzyme (Catalase (CAT), Peroxidase (POD), Superoxide dismutase (SOD), Glutathione peroxidase (GSH-PX)) activities were determined by the colorimetric method. Enzyme gene (CAT, SOD) expression was measured by real time-PCR. RESULTS: The MTS antioxidant activity results showed the combination of C-3 + EGb exhibited synergistic effects especially at the ratio 5:1. Components of isorhamnetin and caffeic acid in C-3 and EGb displayed strong antioxidant activities on MTS and their combination also showed significant synergy in promoting H2O2 production. The combinations of C-3 + EGb and isorhamnetin + caffeic acid promoted CAT and SOD enzyme activities and the ratio 1:1 exhibited the strongest synergy while no obvious promotion on POD and GSH-PX enzyme activities was found. Both combinations above promoted gene expression of CAT and SOD enzymes and the ratio 1:1 exhibited the strongest synergy. CONCLUSIONS: Antioxidant activity results in MTS further confirmed the significant synergy of C-3 combined with EGb and isorhamnetin combined with caffeic acid. The synergy of C-3 combined with EGb may be attributed to the combination of isorhamnetin + caffeic acid, which promoted CAT and SOD enzyme gene expression and further promoted the enzyme activities in E. coli. This study could further provide rational basis for optimizing the physiological bioavailability of P. fruticosa by using natural and safe antioxidants in low doses to produce new medicines and functional products.

The specific aim of this course is development of a university dance curriculum that will link post-modern dance with Tai Chi as it is understood and practiced by the masters of the discipline in China – both as a practice (i.e., as a set of physical movements known as “Tai Chi Chuan”) and as a spiritual discipline (i.e., “Tai Chi”) worthy of scholarly study. A central hypothesis of this course is that the teaching of Tai Chi Chuan in this country – both in academic and experiential contexts – has generally missed the essence of the actual Chinese discipline by concentrating more on the specific physical steps than on the deeper mental and spiritual principles from which it derives. A major goal of the course is to restore to the curriculum those important principles of employing certain meditation techniques that have not been taught here. The course will apply two central principles of Tai Chi in the context of dance: first, the goal of awareness, or softness, which is simply movement based on stillness; and second, the goal of relational physics, or the intention and orientation of the individual to the whole.

An orthogonally (80.3%) preparative two-dimensional hydrophilic interaction chromatography/reversed-phase liquid chromatography method has been established for the isolation and purification of flavonoids from Saxifraga tangutica. Initially, flavonoids were enriched by means of a middle-pressure chromatographic tower (containing middle chromatogram isolated gel). In the first dimension, a XION preparative column was used to separate the flavonoid fractions under the guidance of characteristic ultraviolet absorption spectra of flavonoids and nine flavonoid fractions were obtained. Then, the coeluted flavonoid fractions were selected for further purification via reversed-phase liquid chromatography with the parent ion peak of quercetin (303), kaempferol (287), or isorhamnetin (317). Several flavonoids could be separated from each hydrophilic interaction chromatography fraction; furthermore, flavonoids with poor resolution in one-dimensional liquid chromatography were isolated in two-dimensional liquid chromatography due to the orthogonality. In addition, this technique was valuable for trace flavonoids, which were concentrated in the first stage and separated in the second stage. In total, 18 flavonoids with either quercetin, kaempferol, or isorhamnetin parent nuclei were targetedly obtained, and 15 flavonoids were obtained for the first time from S. tangutica. These results established that the off-line two-dimensional hydrophilic interaction chromatography/reversed-phase liquid chromatography technique was efficient for the isolation of flavonoids from Saxifraga tangutica.

An orthogonally (80.3%) preparative two-dimensional hydrophilic interaction chromatography/reversed-phase liquid chromatography method has been established for the isolation and purification of flavonoids from Saxifraga tangutica. Initially, flavonoids were enriched by means of a middle-pressure chromatographic tower (containing middle chromatogram isolated gel). In the first dimension, a XION preparative column was used to separate the flavonoid fractions under the guidance of characteristic ultraviolet absorption spectra of flavonoids and nine flavonoid fractions were obtained. Then, the coeluted flavonoid fractions were selected for further purification via reversed-phase liquid chromatography with the parent ion peak of quercetin (303), kaempferol (287), or isorhamnetin (317). Several flavonoids could be separated from each hydrophilic interaction chromatography fraction; furthermore, flavonoids with poor resolution in one-dimensional liquid chromatography were isolated in two-dimensional liquid chromatography due to the orthogonality. In addition, this technique was valuable for trace flavonoids, which were concentrated in the first stage and separated in the second stage. In total, 18 flavonoids with either quercetin, kaempferol, or isorhamnetin parent nuclei were targetedly obtained, and 15 flavonoids were obtained for the first time from S. tangutica. These results established that the off-line two-dimensional hydrophilic interaction chromatography/reversed-phase liquid chromatography technique was efficient for the isolation of flavonoids from Saxifraga tangutica.

The article discusses the significance of teaching with mindfulness and tackles the author's experience of understanding the wisdom in Buddhism religion.

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