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Three new alkaloids, N-hexacosanoylanthranilic acid (1), N-octacosanoylanthranilic acid (2) and N-eicosanoyltyramine (3), along with 19 known compounds, were isolated from the seeds of Notopterygium incisum, whose rhizomes are used as a traditional Tibetan medicine. Their structures were elucidated by 1D, 2D NMR spectra and ESI-MS spectrometer evidence.

From the aerial parts of <i>Senecio dianthus</i>, four new eremophilenolides (<b>1</b>-<b>4</b>, resp.) and one new eremophilenolide alkaloid (<b>5</b>), of the relatively uncommon eremophilenoid-type sesquiterpenoid lactones, were isolated together with three known sesquiterpenoid lactones, 10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>6</b>), 8<i>β</i>,10<i>β</i>-dihydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>7</b>), and 10<i>α</i>-hydroxy-1-oxoeremophila-7(11),8(9)-dien-12,8-olide (<b>8</b>). On the basis of IR, MS, and NMR data, particularly 2D-NMR analyses, the structures of the new compounds were established as: 2<i>β</i>-(angeloyloxy)-10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>1</b>), 6<i>β</i>-(angeloyloxy)-10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>2</b>), 2<i>β</i>-(angeloyloxy)-8<i>β</i>,10<i>β</i>-dihydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>3</b>), 2<i>β</i>-(angeloyloxy)-8<i>α</i>-hydroxyeremophila-7(11),9(10)-dien-12,8<i>β</i>-olide (<b>4</b>), and 8<i>β</i>-amino-10<i>β</i>-hydroxyeremophil-7(11)-en-12,8<i>α</i>-olide (<b>5</b>). In addition, the relative configuration of <b>1</b> was corroborated by X-ray diffraction analysis.

A new proaporphine alkaloid, 8, 9-dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of Meconopsishorridula Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods.

A new proaporphine alkaloid, 8, 9<b>-</b>dihydroprooxocryptochine (1), together with three known alkaloids, was isolated from the aerial parts of <b>Meconopsis</b> <b>horridula</b> Hook. f. & Thomson (Papaveraceae), a traditional Tibetan medicine. The structure of 1 was determined by spectroscopic methods.<br>8, 9-Dihydroprooxocryptochine, a new proaporphine alkaloid from <b>Meconopsis</b> <b>horridula</b>, a tradional Tibetan medicine.<br>▪

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5 : 2.5 : 3 : 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by (1)H-NMR and (13)C-NMR data.

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5 : 2.5 : 3 : 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by (1)H-NMR and (13)C-NMR data.

Small-molecule fluorescence imaging in the second near-infrared (NIR-II, 1000-1700 nm) window has gained increasing interest in clinical application. Till now, very few studies have been exploited in the small-molecule fluorophores with both excitation and emission in the NIR-II window. Inspired by the indocyanine green structure, a series of polymethine dyes with both absorption and emission in the NIR-II window have been developed for NIR-II imaging, providing the feasibility to directly compare optical imaging in the NIR-IIa (1300-1400 nm) subwindow under 1064 nm excitation with that in the NIR-II window under 808 nm excitation. The signal-background ratio and the tumor-normal tissue ratio achieved great improvement under 1064 nm excitation in the imaging of mouse blood pool and U87 glioma tumors. Our study not only introduces a broadband emission fluorophore for both NIR-II and NIR-IIa imaging, but also reveals the advantages of NIR-II excitation over NIR-I in in vivo imaging.

A selective and affinitive molecularly imprinting polymer (MIP) was prepared to podophyllotoxin (PPT) using a non-covalent imprinting approach. The imprinted conditions including the kind and relative amounts of functional and cross-linking monomers were carefully optimized. The binding characteristics of the imprinted polymer were evaluated in different solvent systems using equilibrium binding experiments. UV spectrum revealed cooperative hydrogen-bonding complex between PPT and acylamide (AM) might be formed at the ratio of 1:2 in the prepolymerized system, and produced two classes of binding sites in the resulting MIP with dissociation constants of 0.337 and 5.76 mmol l−1, and the affinity binding sites of 78.67 and 346.0 μmol g−1, respectively. Selective binding of the template molecule is demonstrated in comparison to the analogue 4′-demethylpipodophyllotoxin (DMEP). Finally, the optimized MIP was used as an adsorbent to extract PPT directly from the ethanol extraction of Chinese traditional Tibetan medicine, <b>Sinopodophyllum emodi</b>. The binding selectivity and recovery of the optimized imprinted polymer had been further estimated by HPCE and compared to its non-imprinted polymer. The obtained results implied a possibility to extract PPT directly from plants by a MIP technique shown in this paper.

High-speed counter-current chromatography (HSCCC) was successfully applied for the first time to isolate and purify four cis-trans isomers of coumaroylspermidine analogs from Safflower. HSCCC separation was achieved with a two-phase solvent system composed of chloroform-methanol-water (1:1:1, v/v/v) with the upper phase as the mobile phase. In a single run, a total of 1.3mg of N(1), N(5), N(10)-(E)-tri-p-coumaroylspermidine (EEE), 4.4mg of N(1)(E)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (EZE), 7.2mg of N(1)(Z)-N(5)-(Z)-N(10)-(E)-tri-p-coumaroylspermidine (ZZE), and 11.5mg of N(1),N(5),N(10)-(Z)-tri-p-coumaroylspermidine (ZZZ) were obtained from 100mg of crude sample. High Performance Liquid Chromatography (HPLC) analysis showed that the purities of these four components are 95.5%, 98.1%, 97.5% and 96.2%, respectively. The chemical structures were identified by ESI-MS, (1)H NMR and (13)C NMR.

High-speed counter-current chromatography (HSCCC) was successfully applied for the preparative separation and purification of N-feruloyl serotonin (NF) and N-(p-coumaroyl) serotonin (NP) from safflower seed meal. After the measurement of partition coefficient of the two target compounds in the two-phase solvent systems, the HSCCC was performed well with a two-phase solvent system composed of CHCl3-methanol-0.1 M HCl at a volume ratio of 1 : 1 : 1, v/v. The upper phase was used as stationary phase and the lower phase was used as mobile phase. Under the optimized condition, 7.5 mg NF and 6.9 mg NP were separated from 40 mg crude sample with the purity of 98.8 and 97.3%, respectively. The structures of the isolated compounds were identified by (1)H NMR and (13)C NMR.

NSM-<i>g</i>-P(MMA-<i>co</i>-BA) resin with super oil-absorbent capability was prepared by grafting co-polymerization using Nitraria seeds meal as filler, methyl-meth-acrylate (MMA) and butyl-acrylate (BA) as monomers, <i>N,N′</i>-methylene-bis-acrylamide (MBA) as crosslinker and peroxide-benzoyl (BPO) as initiator. The structure of obtained products was analyzed using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), respectively. The oil absorbency, reusability, oil-retention capacity, thermodynamics, and the removal of oil from the surface of 0.9 wt% NaCl solutions were examined further. The results showed that NSM-<i>g</i>-P(MMA-<i>co</i>-BA) can absorb lubrication up to 29.6 times of its weight, 24.3 times for colza oil, 22.7 times for diesel, and 21 times for gasoline. The exhausted NSM-<i>g</i>-P(MMA-<i>co</i>-BA) can be recollected and recovered through extraction or drying approach. More importantly, the oil sorption capacity of recovered NSM-<i>g</i>-P(MMA-<i>co</i>-BA) only has a slight decline after six sorption cycles. The thermodynamic studies indicated that adsorption procedure with complex physical and chemical sorption is spontaneous and exothermic. In general, the present composite resins have exhibited potential applications in cleanup of oil spills because of their good hydrophobicity, lipophilicity, and excellent network structure. Also, the findings of this study might provide a convenient and economic method for fast and selective removal of oil from surface of wastewater. POLYM. COMPOS., 39:1051-1063, 2018. © 2016 Society of Plastics Engineers

A method of using high-speed counter-current chromatography (HSCCC) for preparative isolation and purification of oligostilbenes from the ethanol extracts of seed kernel of Iris lactea Pall. var. chinensis (Fisch.) Koidz was established in this study. Four oligostilbenes were successfully separated and purified by HSCCC with two sets of two-phase solvent system, n-hexane-ethyl acetate-methanol-water (3:6:4.2:5.5, v/v/v/v) in the head-to-tail elution mode for the first separation to mainly isolate vitisin A (58 mg), ɛ-viniferin (76 mg) and peak II (43 mg) from 300 mg of the crude ethanol extracts, and then light petroleum-ethyl acetate-methanol-water (5:5:3:6, v/v/v/v) in the tail-to-head elution mode for the second separation to isolate vitisin B (52 mg) and vitisin C (11 mg) from 100mg of peak II. The purities of the isolated four oligostilbenes were all over 95.0% as determined by HPLC. Vitisin A, vitisin B and vitisin C, resveratrol tetramers, were isolated from Iris lactea for the first time. The preparation of crude sample was simple and the HSCCC method for the isolation and purification of four oligostilbenes was rapid, efficient and economical.

OBJECTIVES: Yoga is promoted as an anti-stress activity, however, little is known about the mechanisms through which it acts. The present study investigated the acute effects of a hatha yoga session, displayed on a video, on the response to and recovery from an acute psychological stressor. METHODS: Twenty-four healthy young adults took part in a counterbalanced, randomized-crossover trial, with a yoga and a control condition (watching TV). Participants attended the laboratory in the afternoon on two days and each session comprised a baseline, control or yoga task, stress task and recovery. Blood pressure (BP), heart rate (HR) and salivary cortisol responses were measured. State cognitive- and somatic-anxiety along with self-confidence were assessed before and after the stressor. RESULTS: Although no difference in the BP or HR responses to stress were found between conditions, systolic BP (p=0.047) and diastolic BP (p=0.018) recovery from stress were significantly accelerated and salivary cortisol reactivity was significantly lower (p=0.01) in the yoga condition. A yoga session also increased self-confidence (p=0.006) in preparation for the task and after completion. Moreover, self-confidence reported after the stress task was considered debilitative towards performance in the control condition, but remained facilitative in the yoga condition. CONCLUSION: Our results show that a single video-instructed session of hatha yoga was able to improve stress reactivity and recovery from an acute stress task in healthy individuals. These positive preliminary findings encourage further investigation in at-risk populations in which the magnitude of effects may be greater, and support the use of yoga for stress reactivity and recovery.

OBJECTIVES: Yoga is promoted as an anti-stress activity, however, little is known about the mechanisms through which it acts. The present study investigated the acute effects of a hatha yoga session, displayed on a video, on the response to and recovery from an acute psychological stressor. METHODS: Twenty-four healthy young adults took part in a counterbalanced, randomized-crossover trial, with a yoga and a control condition (watching TV). Participants attended the laboratory in the afternoon on two days and each session comprised a baseline, control or yoga task, stress task and recovery. Blood pressure (BP), heart rate (HR) and salivary cortisol responses were measured. State cognitive- and somatic-anxiety along with self-confidence were assessed before and after the stressor. RESULTS: Although no difference in the BP or HR responses to stress were found between conditions, systolic BP (p=0.047) and diastolic BP (p=0.018) recovery from stress were significantly accelerated and salivary cortisol reactivity was significantly lower (p=0.01) in the yoga condition. A yoga session also increased self-confidence (p=0.006) in preparation for the task and after completion. Moreover, self-confidence reported after the stress task was considered debilitative towards performance in the control condition, but remained facilitative in the yoga condition. CONCLUSION: Our results show that a single video-instructed session of hatha yoga was able to improve stress reactivity and recovery from an acute stress task in healthy individuals. These positive preliminary findings encourage further investigation in at-risk populations in which the magnitude of effects may be greater, and support the use of yoga for stress reactivity and recovery.

Two novel organic amide alkaloids, 4-[(<i>E</i>)-<i>p</i>-coumaroylamino]butan-1-ol (<b>1</b>) and 4-[(<i>Z</i>)-<i>p</i>-coumaroylamino]butan-1-ol (<b>2</b>), together with a rare pyridoindole alkaloid, hippophamide (<b>3</b>), were isolated from the seed residue of <i>Hippophae rhamnoides</i> Linn. subsp. <i>sinensis</i> Rousi. Their structures were determined by spectroscopic means. The results show that compounds <b>1</b> and <b>2</b> are (<i>E</i>/<i>Z</i>)<i>-</i>isomers, compound <b>3</b>, a pyridoindole alkaloid concerted with <i>γ</i>-lactam ring.

Three new flavone C-glycosides, paraquinins A-C, were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan medicine distributed in the Qinghai-Tibet plateau. On the basis of 1D and 2D NMR evidence, their structures were elucidated as acacetin-6-C-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (1), acacetin-6-C-α-L-rhamnopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (2), and acacetin-6-C-α-L-rhamnopyranosyl-(1 → 2)-(6'''-O-E-feruloyl)-β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (3).

Background: The stems of Tinospora sinensis (Lour.) Merr commonly named "Kuan-Jin-Teng" in Chinese, have been used to treat rheumatoid arthritis as a Tibetan medicine.Purpose: The effects of the EtOAc fraction of ethanolic extract from the stems of T. sinensis (KJT) on the pro-inflammatory cytokines and MAPK pathway were studied in collagen-induced arthritis (CIA) model.Study Design: Anti-arthritic activity of KJT was investigated in CIA model.Methods: The chemical constituents of KJT were analyzed by LC-MS and HPLC. The CIA model was established with injecting the bovine CII emulsified in Freund's adjuvant in Wistar rats. Several doses of KJT (50.0, 100.0 and 200.0 mg/kg) were administrated via oral gavage to CIA rats daily for 4 weeks. The anti-arthritic activity of KJT was investigated by clinical arthritis scoring, paw swelling inspection and hyperalgesia measurement, as well as radiological and histological analysis in CIA rats. The impacts of KJT on the activation of MAPK pathway, production of pro-inflammatory cytokines (TNF-α, IL-1β and IL-17) in ankle joints, serum, and spleen in CIA rats were examined by western blot, immunohistochemical staining, ELISA, and quantitative real-time PCR respectively. Lastly, the effects of KJT on production of the nitric oxide (NO) and pro-inflammatory cytokines as well as the regulation of the phosphorylation of p38 and Erk were detected in lipopolysaccharide (LPS)-stimulated RAW264.7 murine macrophage cells.Results: KJT significantly alleviated the paw swelling, hyperalgesia and arthritic severity, and reduced the synovial tissue proliferation and inflammatory cell infiltration in the CIA rats. Moreover, KJT suppressed the production of TNF-α, IL-1β, and IL-17 in ankle joints, serum, and spleen and reversed the up-regulation of the phosphorylation of p38 and Erk in CIA rats. KJT was also demonstrated to inhibit the production of NO and pro-inflammatory cytokines (TNF-α, IL-1β and IL-6), and phosphorylation of p38 and Erk in LPS-stimulated RAW264.7 cells.Conclusion: These results suggest the mechanisms of KJT performing its anti-arthritis effect may be attributed to inhibiting the production of pro-inflammatory cytokines and down-regulating the MAPK signaling pathway.

Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.

Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.

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