Phytochemical studies on the whole herb of Sphaerophysa salsula has resulted in the discovery of one new 8-isopentenyl isoflavone derivative, named sphaerosin s2 (3-(8-(2-hydroxypropan-2-yl)-3,4-dihydro-2H-furo[2,3-h]chromen-3-yl)-2,6-dimethoxyphenol) (1), along with four know 8-isopentenyl isoflavone derivatives (2-5). Compounds (2, 4 and 5) were isolated for the first time from this species. Their structures were elucidated on the basis of ESI-MS, UV, IR, 1D NMR and 2D NMR data.
OBJECTIVES: The hepatoprotective effect of Gentianae macrophyllae root extract (GME) on alcoholic liver disease (ALD) was evaluated through ethanol induced ALD animal model.METHODS: Mice were randomly divided into control normal group (10 mice), ethanol-induced ALD model group (10 mice) and GME plus ethanol group (30 mice). Mice in model group were given intragastric administration with 50% (v/v) ethanol aqueous solution (200 μl for each) once daily for 19 days. Mice in control normal group received equal volumes of water. Mice in GME plus ethanol group were given intragastric administration with 50% (v/v) ethanol aqueous solution (200 μl for each) once daily at 10:00 a.m., after 1 h, mice in GME group sequentially were treated with 20, 40 and 100 mg/kg of GME by gastric gavage for 19 days. the average food and water consumed by the mice in every group were recorded every 2 days and body weight of every mouse in every group was measured every 2 days.
KEY FINDINGS: Results showed that GME significantly improved alcohol induced liver injury in a dose-dependent manner. The impaired hepatic tissue structure was repaired and the collagen deposition declined after GME administration. Meanwhile, the level of malonaldehyde (MDA), Aspartate transaminase (AST) and alanine transaminase (ALT) (indicators of liver damage) in blood serum were significantly controlled by GME with a dose-dependent manner, moreover, body weight and liver index were also improved after administration of GME. Pro-inflammatory cytokines including MCP-1, TNF-α, IL-1 and IL-6 were detected through RT-PCR and ELISA in experiment and GME can significantly inhibit the expression of TNF-α, IL-1 and IL-6 but have no effect on MCP-1. In order to explore the mechanism of GME on ALD, MAPKs pathway was examined and results indicated that GME attenuated ALD through inhibiting the phosphorylation of JNK and P38 and further suppressing the initiation of inflammation.
CONCLUSIONS: GME attenuated ALD through inhibiting the phosphorylation of JNK and P38 and further suppressing the initiation of inflammation.
Background: Dracocephalum heterophyllum was a traditional Tibetan medicine possesses various pharmacological effects involved in anti-inflammatory, antibacterial activities. However, its anti-hepatitis, antioxidant activity and bioactive compounds have not been reported, the objective of this research work was to investigate the pharmacological activity and bioactive compounds of D. heterophyllum extracts. Results: In the present study, the anti-hepatics and antioxidant activities of four D. heterophyllum extracts (i.e. petroleum ether extracts, ethyl acetate extracts, n-BuOH extracts, and water extracts) were conducted. The main chemical constituent of petroleum ether and ethyl acetate extracts were also isolated using chromatographic techniques and identified by NMR spectroscopic methods. The anti-hepatitis assay showed that the petroleum ether and ethyl acetate extracts of D. heterophyllum significantly prolonged the mean survival times and reduced the mortality of mouse hepatitis model induced by concanavalin A (ConA). The levels of alanine transaminase, aspartate transaminase in blood serum could be decreased obviously by ethyl acetate extracts compared with ConA group (P < 0.01). The histological analysis demonstrated that the ethyl acetate extracts could inhibit apoptosis and necrosis caused by ConA. In addition, the antioxidant activities of the four extracts of D. heterophyllum were measured by DPPH assay, ABTS assay, anti-lipidperoxidation assay, ferric reducing antioxidant power assay, ferrous metal ions chelating assay and determination of total phenolic contents. The results showed that the ethyl acetate extract had the highest antioxidant activities, followed by petroleum ether extract. Finally, nine mainly compounds were isolated from the Petroleum ether and ethyl acetate extracts, including four triterpenes: oleanolic acid ( 1), ursolic acid ( 2), pomolic acid ( 3), 2α- hydroxyl ursolic acid ( 4), three flavonoids: apigenin-7- O-rutinoside ( 5), luteolin ( 8), diosmetin ( 9) and two phenolic acids: rosmarinic acid ( 6), methyl rosmarinate ( 7). Conclusion: The Ethyl acetate extract of D. heterophyllum had the highest anti-hepatitis and antioxidants activities, followed by petroleum ether extract. The bioactive substances may be triterpenes, flavonoids and phenolic acids, the ethyl acetate extracts of D. heterophyllum may be possible candidates in developing anti-hepatitis medicine.
BACKGROUND: In previous investigation, we have identified antioxidative effects of water-soluble ethanolic extracts (named as AKE) from Arenaria kansuensis and inferred that these extracts or their constituents may also have antihypoxic activity. A. kansuensis has been widely used in traditional Tibetan medicine for altitude sickness (AS) and has been known as the herb of anti-inflammatory and hypoxia resistance for a long time.PURPOSE: The purpose of this study is to evaluate protective effects of AKE and its major constituents against hypoxia-induced lethality in mice and RSC96 cells.
STUDY DESIGN AND METHODS: Hypoxia-induced lethality in mice was investigated by 3 experimental animal models of hypoxia. Meanwhile, we established a RSC96 cell model of hypoxia which applied to screen and assess the anti-hypoxic activity of compounds isolated from A. kansuensis.
RESULTS: Results indicated that AKE dose-dependently prolonged survival time of hypoxia induced lethality in mice compared to vehicle group and exhibited significantly anti-hypoxic effect. AKE also enhanced the number of red blood cells (RBC) and the concentration of hemoglobin (HB). 8 compounds were bio-guided separated and purified from AKE based on the animal model and cell model of hypoxia. Among which pyrocatechol (C16) and tricin 7-O-β-d-glucopyranoside (C13) were confirmed to express better protective effects on cell damage induced by hypoxia, suggesting that these two compounds are major active constituents of AKE for anti-hypoxia.
CONCLUSION: This study demonstrated that pyrocatechol and tricin 7-O-β-d-glucopyranoside could be therapeutic candidates for treatment of AS. It is the first time to find the major active constituents of AKE for anti-hypoxia. Meanwhile, a RSC96 cell model of hypoxia was established to screen anti-hypoxic activity of compounds for the first time.
Six compounds were isolated from an ethanol extract of Swertia mussotii and identified as 2-phenylethyl-β-D-glucoside (1), amaroswerin (2), 1,3,7,8-tetrahydroxyxanthone (3), swertiamarine (4), 1,3,8-trihydroxy-5-methoxyxanthone (5) and methylswertianin (6). Compounds 1, 2 and 6 were isolated from S. mussotii for the first time. The anti-inflammatory activities of the compounds were evaluated by determining their effect on the production of NO by LPS-stimulated RAW264.7 cells. Amaroswerin was the most potent inhibitor of NO release, with an IC50 value of 5.42 μg/mL. Treatment with amaroswerin inhibited expression of iNOS at both protein and mRNA levels. Amaroswerin also dose-dependently suppressed production of TNF-α, IL-6 and IL-1β and reduced expression of mRNA for these LPS-stimulated pro-inflammatory mediators. Amaroswerin thus inhibits the expression of iNOS, TNF-α, IL-6 and IL-1β by downregulating transcription in LPS-induced RAW264.7 macrophage cells, indicating that amaroswerin may be a valuable therapeutic agent for the treatment of inflammatory diseases.
ETHNOPHARMACOLOGICAL RELEVANCE: Erigeron multiradiatus (Lindl.) Benth., an herb that grows in the alpine and subalpine meadow of Qinghai-Tibet plateau, has been widely used as a folk remedy by the native people for treatment of various inflammatory ailments.AIM OF THE STUDY: In order to isolate and identify the active components of Erigeron multiradiatus for anti-inflammatory activity, a preliminary phytochemical study and a bioassay-guided fractionation and purification process was performed.
MATERIAL AND METHODS: The dry whole plant Erigeron multiradiatus was extracted with 50% ethanol and then separated into CHCl(3), n-BuOH, and aqueous fractions. The anti-inflammatory activities of each fraction were investigated using two in vivo inflammation models.
RESULTS: These results exhibited varying degrees of anti-inflammatory activities and the n-BuOH fraction showed the strongest anti-inflammatory activities. The n-BuOH fraction was then subjected to separation and purification using macroporous resins column chromatography and Sephadex LH-20 leading to two flavonoids glucuronides identified as scutellarein-7-O-beta-glucuronide and apigenin-7-O-beta-glucuronide. Furthermore, LC-MS/MS identification and quantification of isolated compounds were also performed.
CONCLUSION: Scutellarein-7-O-beta-glucuronide and apigenin-7-O-beta-glucuronide were considered as major components and principally responsible for the anti-inflammatory activity of Erigeron multiradiatus. Thus the results of our study provide a scientific basis for the utilization of Erigeron multiradiatus in traditional Tibetan medicine.
Background: Hypecoum leptocarpum Hook. f. et Thoms., which is used in traditional Tibetan medicine as an antipyretic, antitussive, analgesic, and anti-inflammatory agent, contains a variety of alkaloids that could be responsible for its analgesic and anti-inflammatory properties. Objective: The present study was designed to investigate the anti-inflammatory activity of the total alkaloids from H. leptocarpum (AHL) in vitro and to elucidate the chemical structure of the anti-inflammatory components in AHL. Materials and Methods: Chemical characterization was performed using liquid chromatography/quadrupole-time-of-flight mass and diode-array detector-high performance liquid chromatography. The anti-inflammatory effects of AHL were investigated by measuring the production of inflammatory cytokines using enzyme-linked immunosorbent assay and mRNA expression by real-time polymerase chain reaction in lipopolysaccharide-induced RAW 264.7 macrophages. Results: Chemical analysis of AHL revealed the presence of seven alkaloids, protopine (13.3%), cryptopine (1.5%), leptopidinine, leptocarpine, corydamine, dihydroleptopine, and oxohydrastinine. AHL significantly suppressed the production of nitric oxide (NO), interleukin-1 beta (IL-1 β), IL-6, and tumor necrosis factor-alpha (TNF-α) in LPS-induced RAW 264.7 cells. The maximum levels of suppression of NO, IL-1 β, IL-6, and TNF-α were 86.8% ± 2.2%, 70.1% ± 1.5%, 100.1% ± 2.5%, and 50.8% ± 3.6%, respectively. IC50values of suppression of cytokine production by AHL were 7.47 ± 2.81 μg/mL (NO), 0.12 ± 0.28 μg/mL (IL-1 β), 0.56 ± 0.37 μg/mL (IL-6), and 18.95 ± 5.23 μg/mL (TNF-α). AHL was also shown to downregulate mRNA expression of inducible NO synthase, IL-1 β, IL-6, and TNF-α in vitro. Conclusion: The study provides convincing evidence that AHL has strong anti-inflammatory activity. The potent activity is likely a result of synergy between the different alkaloids. Abbreviations used: The total alkaloids from H. leptocarpum: AHL; Nitric oxide: NO; Interleukin-1 beta IL-1β; Interleukin-6: IL-6; Tumor necrosis factor-alpha: TNF-α; Prostaglandin E2: PGE2; Inducible nitric oxide synthase: iNOS; Nonsteroidal anti-inflammatory drugs: NSAIDs; lipopolysaccharide: LPS; The total ion chromatograms: TIC; The liquid chromatography/quadrupole-time of flight: LC/Q-TOF; Nuclear factor-kappa B: NF-κB; Janus kinase-signal transducers and activators of transcription: JAK-STAT. [ABSTRACT FROM AUTHOR]
Bioactive equivalent combinatorial components play a critical role in herbal medicines. However, how to discover and enrich them efficiently is a question for herbal pharmaceuticals researchers. In our work, a novel two-dimensional reversed-phase/hydrophilic interaction high-performance liquid chromatography method was established to perform real-time components trapping and combining for preparation and isolation of coeluting components. Arenaria kansuensis was taken as an example, and solid-phase extraction coupled with liquid-liquid extraction as a simple and efficient method for enriching trace components, reversed phase column coupled with hydrophilic interaction liquid chromatography XAmide column as two-dimensional chromatography technology for isolation and preparation of coeluting constituents, enzyme-linked immune-sorbent assay as bio-guided assay, and anti-inflammatory bioactivity evaluation for bioactive constituents. A combination of 12 β-carboline alkaloids was identified as anti-inflammatory bioactive equivalent combinatorial components from A. kansuensis, which accounts for 1.9% w/w of original A. kansuensis. This work answers the key question of which are real anti-inflammatory components from A. kansuensis and provides a fast and efficient approach for discovering and enriching trace β-carboline alkaloids from herbal medicines for the first time. More importantly, the discovery of bioactive equivalent combinatorial components could improve the quality control of herbal products and inspire a herbal medicine based on combinatorial therapeutics.
Yak butter is one of the most important foods for the Tibetan people. Of note, its production yields waste yak milk as a by-product. In this work, waste yak milk protein hydrolysates made via Pepsin hydrolysis were shown to have antimicrobial activity. Furthermore, an innovative method of magnetic liposome adsorption combined with reversed-phase high performance liquid chromatography (RP-HPLC) was developed to screen for and purify the antimicrobial peptides. Two antimicrobial peptides were obtained and their amino acid sequences were determined by N-sequencing, namely Arg-Val-Met-Phe-Lys-Trp-Ala and Lys-Val-Ile-Ser-Met-Ile. The antimicrobial activity spectra of Arg-Val-Met-Phe-Lys-Trp-Ala included Bacillus subtilis, Staphylcoccus aureus, Listeria innocua, Escherichia coli, Enterobacter cloacae and Salmonella paratyphi, while the Lys-Val-Ile-Ser-Met-Ile peptide shows not only bacterial growth inhibition but also of fungi. Haemolytic testing suggested that these two antimicrobial peptides could be considered to have no haemolytic effect at their minimum inhibitory concentrations (MICs).
Jerusalem artichoke (JA, Helianthus tuberosus L.) has been researched extensively due to its wide range of uses, but there are limited studies on its flowers. In this study, we report the first detailed phytochemical study on JA flowers, which yielded 21 compounds. Compound 4 was identified as a major water-soluble yellow pigment of JA flowers. In addition, the methanol extract of JA flowers and the isolates were evaluated for their antioxidant and α-glucosidase inhibitory activities. Among the tested compounds, compound 13 showed the strongest ABTS+ free radical scavenging activity with SC50 value of 2.30 ± 0.13 μg/mL, and compound 6 showed most potent α-glucosidase inhibitory activity with inhibition rate of 60.0% ± 10.3% at a concentration of 250 μg/mL. Results showed that methanol extract of JA flowers exhibited antioxidant and α-glucosidase inhibitory activities which could be attributed to its phenolic ingredients including chlorogenic acid derivatives, flavonoids and phenols.
<br>Display Omitted<br> Two new phenolic acids (<b>1</b>⿿<b>2</b>) were isolated from the aerial parts of <b>Asterothamnus centrali-asiaticus</b>. Five knownphenolic acids (<b>3</b>⿿<b>7</b>) were also obtained from the title plant. <b>1</b>⿿<b>7</b> were evaluated for their anti-oxidant activity. <b>1</b>⿿<b>7</b> showed anti-oxidant activity with IC50 values ranging from 7.65 to 22.44 μg/mL.<br>Two new phenolic acids 2-hydroxy-5-[(6⿲-<b>O</b>-(<b>E</b>)-caffeoyl)-β-d-glucopyranosyl]-oxybenzoic acid (<b>1</b>) and 2-hydroxy-5-[(3⿲-<b>O</b>-(<b>E</b>)-caffeoyl)-β-d-glucopyranosyl]-oxybenzoic acid (<b>2</b>) were isolated from the aerial parts of <b>Asterothamnus centrali-asiaticus</b>, together with five known ones (<b>3</b>-<b>7</b>). Their structures were elucidated by extensive 1D and 2D NMR studies and HRESIMS investigations. The anti-oxidant activity of the isolates was evaluated through ABTS radical cation decolorization assay. The results showed that all of them exhibited anti-oxidant activity, and compound <b>7</b> was the most active compound with an IC50 value of 7.65 μg/mL.
The young leaves and shoots of Sibiraea laevigata, known as "Liucha", are used as tea by Tibetans to improve digestion after meals. Long-term consumption of "Liucha" will cause weight loss. In present work, we reported on the isolation and NMR and chemical analysis-based elucidation of seven new sorbitol O-caffeic acid ester derivatives named sorbitol esters A-G (1-7) and eighteen known phenolic compounds from S. laevigata. All of the isolates were evaluated for their antioxidant and α-glucosidase inhibitory activities. Among them sorbitol ester A (1), sorbitol ester D (4), sorbitol ester F (6), sorbitol ester G (7), isoferulic acid (15), methyl caffeate (18), trans-p-hydroxycinnamic acid (19), and kaempferol 3-O-β-d-(6″-E-p-coumaroyl)-glucopyranoside (25) showed more potent α-glucosidase inhibitory activity than the clinical drug acarbose.
• <b>Saxifraga tangutica</b> Engl. is a promising source of antioxidants against DPPH and FRAP. • The 50% ethanol extract of S. <b>tangutica</b> showed strong antioxidative activity against DPPH and FRAP. • Eight phenols were isolated from S. <b>tangutica</b>; all of the compounds are reported for the first time from this plant. • The antioxidative S. <b>tangutica</b> extracts and isolated phenols supports the antioxidant of this plant.<br><b>Saxifraga tangutica</b> Engl., is a medicinal herb that grows on the Qinghai-Tibet Plateau. Extracts and phenols from the Qinghai population have been subjected to antioxidative assays against DPPH radical-scavenging and reducing power (FRAP). The 50% ethanol extract showed strong antioxidative activity against DPPH and FRAP, with IC50 ± SEM [μg/mL] values of 9.38 ± 0.46 and 15.46 ± 0.52, respectively. The antioxidative activity-guided fractionations were performed according to the DPPH and FRAP screening results. Fourteen fractions from the 50% ethanol extract showed dissimilar antioxidative activity against DPPH and FRAP of 8.16 ± 0.76 ∼ 38.42 ± 0.58 μg/mL and 13.22 ± 0.68 ∼ 61.47 ± 0.49 μg/mL. The chemical assay-guided separation of the active fractions (fractions 3, 6, 7 and 8) led to eight phenols: protocatechuic aldehyde (<b>1</b>), ethyl gallate (<b>2</b>), rhododendrin (<b>3</b>), <b>p</b>-hydroxyacetophenone (<b>4</b>), rhododendrol (<b>5</b>), protocatechuic acid ethyl ester (<b>6</b>), frambinone (<b>7</b>) and ethylparaben (<b>8</b>). All phenols are reported here for the first time from <b>S. tangutica</b> Engl. Protocatechuic aldehyde (<b>1</b>), ethyl gallate (<b>2</b>), rhododendrin (<b>3</b>) and protocatechuic acid ethyl ester (<b>6</b>) showed strong antioxidative activities (IC50 ± SEM [mM] between 8.79 ± 0.15 and 4.25 ± 0.47 and between 6.15 ± 0.48 and 2.83 ± 0.49) against DPPH and FRAP.
A method that involved the combination of pH-zone-refining counter-current chromatography and semipreparative reversed-phase liquid chromatography has been established for the preparative separation of alkaloids from Hypecoum leptocarpum. From 1.2 g of crude sample, 31 mg N-feruloyltyramine, 27 mg oxohydrastinine, 47 mg hydroprotopine, 25 mg leptopidine, and 18 mg hypecocarpine have been obtained. The structure of the new compound, hypecocarpine, is confirmed based on the analysis of spectroscopic data, including NMR, UV, and IR spectroscopy and positive electrospray ionization mass spectrometry. The known chemical structures were characterized on the basis of (1) H and (13) C NMR spectroscopy. The purities of the five alkaloids are all over 92.7% as determined by high-performance liquid chromatography. The alkaloids' cytotoxicity in breast cancer cells is assessed by using a Cell Counting Kit assay and their inhibitory effect on fatty acid synthase expression is assessed by a Western blot assay. These results suggest that leptopidine could suppress growth and induce cytotoxicity in breast cancer cells and that the cytotoxicity of leptopidine may be related to its inhibitory effect on fatty acid synthase expression.
This study presents an efficient strategy based on liquid-liquid extraction, high-speed counter-current chromatography, and preparative HPLC for the rapid enrichment, separation, and purification of four anthraquinones from Rheum tanguticum. A new solvent system composed of petroleum ether/ethyl acetate/water (4:2:1, v/v/v) was developed for the liquid-liquid extraction of the crude extract from R. tanguticum. As a result, emodin, aloe-emodin, physcion, and chrysophanol were greatly enriched in the organic layer. In addition, an efficient method was successfully established to separate and purify the above anthraquinones by high-speed counter-current chromatography and preparative HPLC. This study supplies a new alternative method for the rapid enrichment, separation, and purification of emodin, aloe-emodin, physcione, and chrysophanol.
In this paper, an efficient method was successfully established by the combination of macroporous resin (MR) and high-speed counter-current chromatography (HSCCC) for rapid enrichment and separation of aloe-emodin 8-O-β-D-glucoside, emodin 1-O-β-D-glucoside, emodin 8-O-β-D-glucoside and piceatannol 4'-O-β-D-(6″-O-gallate)-glucoside. Six kinds of macroporous resins were investigated in the first step and X-5 macroporous resin was selected for the enrichment of the target compounds. The recoveries of the target compounds reached 89.0, 85.9, 82.3 and 84.9% respectively after 40% ethanol elution. In the second step, the target compounds were separated by HSCCC with a two-phase solvent system composed of chloroform/ethyl acetate/methanol/water (8:1:6:5, v/v). The established method will be helpful for further characterization and utilization of Rheum tanguticum. The results demonstrate that MR coupled with HSCCC is a powerful technique for separation of bioactive compounds from natural products.
A comparative analysis was undertaken to conduct an anatomical and micromorphological study of five species of Rhodiola—<i>R. kirilowii, R. yunnanensis, R. crenulata, R. fastigata</i>, and <i>R. quadrifida</i>—collected from the western Sichuan province plateau of China. Rhodiola plants are a popularly used ethnodrug from the Qinghai-Tibetan plateau of China. Modern studies have shown that the plants of Rhodiola possess different pharmacological activities, chemical constituents, and efficiencies in clinical application. To distinguish five main species of Rhodiola and ensure their safety and efficacy, microscopic characteristics of roots, rhizomes, and stems, including transverse sections, stem and foliar epidermis, as well as the crude drug powder, were observed. The fixed, sectioned, and stained plant materials, as well as the crude powder, were studied using a light microscope according to the usual microscopic techniques. The results of the microscopic features were systematically and comparatively described and illustrated. The five species have distinct microscopic characteristic differences, thus allowing us to distinguish between the species. Also, semi-quantitative and quantitative micrographic parameter tables were simultaneously presented. Further, a key to the five species and a comparative chart of the key authentication parameters based on these anatomic characteristics analyzed was drawn up and is presented for the Rhodiola species studied. The study indicated that light microscopy and related techniques provide a method that is convenient, feasible, and can be unambiguously applied to the authentication of species of Rhodiola. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc.
Rhodiola is an increasingly widely used traditional Tibetan medicine and traditional Chinese medicine in China. The composition profiles of bioactive compounds are somewhat jagged according to different species, which makes it crucial to identify authentic Rhodiola species accurately so as to ensure clinical application of Rhodiola . In this paper, a nondestructive, rapid, and efficient method in classification of Rhodiola was developed by Fourier transform near-infrared (FT-NIR) spectroscopy combined with chemometrics analysis. A total of 160 batches of raw spectra were obtained from four different species of Rhodiola by FT-NIR, such as Rhodiola crenulata , Rhodiola fastigiata , Rhodiola kirilowii , and Rhodiola brevipetiolata . After excluding the outliers, different performances of 3 sample dividing methods, 12 spectral preprocessing methods, 2 wavelength selection methods, and 2 modeling evaluation methods were compared. The results indicated that this combination was superior than others in the authenticity identification analysis, which was FT-NIR combined with sample set partitioning based on joint x-y distances (SPXY), standard normal variate transformation (SNV) + Norris-Williams (NW) + 2nd derivative, competitive adaptive reweighted sampling (CARS), and kernel extreme learning machine (KELM). The accuracy (ACCU), sensitivity (SENS), and specificity (SPEC) of the optimal model were all 1, which showed that this combination of FT-NIR and chemometrics methods had the optimal authenticity identification performance. The classification performance of the partial least squares discriminant analysis (PLS-DA) model was slightly lower than KELM model, and PLS-DA model results were ACCU = 0.97, SENS = 0.93, and SPEC = 0.98, respectively. It can be concluded that FT-NIR combined with chemometrics analysis has great potential in authenticity identification and classification of Rhodiola , which can provide a valuable reference for the safety and effectiveness of clinical application of Rhodiola . [ABSTRACT FROM AUTHOR]
<p>A Tibetan-Chinese dictionary of the Lhasa colloquial dialect. (Michael Walter and Manfred Taube 2006-05-15, revised by Bill McGrath 2008-01-03)</p>
An alarming number of students drop out of junior high school in developing countries. In this study, we examine the impacts of providing a social-emotional learning (SEL) program on the dropout behavior and learning anxiety of students in the first two years of junior high. We do so by analyzing data from a randomized controlled trial involving 70 junior high schools and 7,495 students in rural China. After eight months, the SEL program reduces dropout by 1.6 percentage points and decreases learning anxiety by 2.3 percentage points. Effects are no longer statistically different from zero after 15 months, perhaps due to decreasing student interest in the program. However, we do find that the program reduces dropout among students at high risk of dropping out (older students and students with friends who have already dropped out), both after eight and 15 months of exposure to the SEL program.
In order to reveal the chemical substance basis of pharmacodynamic effects of Zuotai, energy dispersive spectrometry of X-ray (EDX), X-ray fluorescence spectroscopy (XRF), synchrotron radiation X-ray absorption fine structure (SR-XAFS), X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM) were used to analyze the elements, the chemical valence and local structure of mercury, and the chemical phase composition and micro-morphology of Zuotai. EDX and XRF analysis shows that the main elements in Zuotai are Hg and S, with some other minor elements, such as 0, Fe, Al, Cu, K, Ag, Ca, Mg etc. SR-XAFS analysis shows that: the oxidation state of mercury in Zuotai is divalence, its neighbor atoms are S, and its coordination number is four. XRD assay found that β-HgS (cubic, F-43m 216) and S8 (orthorhombic, Fddd 70) are the main phase compositions in Zuotai. Besides, it also has a small amount of C (hexagonal, P63/mmc 194), Fel.05 S0.95 (hexagonal, P63/mmc 194), Cu6S6 (hexagonal, P63/mmc 194), Cu1.8 S (cubic, F-43m 216) and so on. And it was found that the crystallinity of Zuotai is about 59%, and the amorphous morphology substance in it is about 41%. SEM and AFM detection suggests that Zuotai is a kind of ancient micro-nano drug, and its particle size is mainly in the range of 100-600 nm, even less than 100 nm, which commonly further aggregate into several to 30 µm loose amorphous particles. In summary, the present study elucidated physicochemical characterization(elements composition, coordination information of mercury, phase composition and micro-morphology) of Zuotai, and it will play a positive role in promoting the interpretation of this mysterious drug.;
The first phytochemical investigation on the roots of <b>Ligularia purdomii</b> led to the isolation and identification of 18 compounds, including two eremophilane sesquiterpenoids (<b>1</b> and <b>2</b>), three benzofuran derivatives (<b>3</b>-<b>5</b>), a triterpenoid (<b>6</b>), two steroids (<b>7</b> and <b>8</b>), nine phenolic components (<b>9</b>-<b>17</b>), and a monofatty glyceride (<b>18</b>). The structural elucidation of the isolated compounds was performed by spectroscopic data and comparison with the literature. Compounds (−)-syringaresinol (<b>11</b>), scopoletin (<b>13</b>), 3,5-dimethoxy-4-hydroxy-benzaldehyde (<b>14</b>), and glycerol monolinoleate (<b>18</b>) have not been recorded in <b>Ligularia</b> genus previously. The chemotaxonomic significance of these isolated compounds has been summarized.<br>• First phytochemical investigation on <b>L. purdomii.</b> • 18 compounds were identified from the acetone extract of <b>L. purdomii.</b> • Four compounds were reported from the genus <b>Ligularia</b> for the first time. • The results had important significance for chemotaxonomy of <b>L. purdomii.</b>
A phytochemical investigation of <b>Saxifraga tangutica</b> led to the isolation of 11 compounds, including eight diarylheptanoids (<b>1</b>-<b>6</b>, <b>10</b> and <b>11</b>) and three phenylpropanoids (<b>7</b>-<b>9</b>). The chemical structures were established by extensive analysis of their MS and NMR spectroscopic data or comparison with literature data. In the present research, we report the isolated compounds <b>1</b>-<b>11</b>, for the first time, in the species <b>S. tangutica</b>. Moreover, compounds <b>1</b>, <b>2</b> and <b>4</b>-<b>11</b> have not been reported from any species in Saxifragaceae family. Furthermore, we discuss the chemotaxonomic significance of the isolated compounds.<br>• Eight diarylheptanoids and three phenylpropanoids have been isolated from <b>Saxifraga tangutica.</b> • Compounds <b>1</b>-<b>11</b> are firstly reported in the species <b>Saxifraga tangutica.</b> • Compounds <b>1</b>, <b>2</b> and <b>4</b>-<b>11</b> are firstly isolated from genus <b>Saxifraga</b> or family Saxifragaceae.
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