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Tibetan medicinal plants have been used for more than 2 000 years. In order to find their differences in antioxidant activity, total phenolics and total flavonoids between "hot-nature" and "cold-nature" herbs, we investigated the antioxidant activities of 40 Tibetan herbs from Qinghai plateau, with 20 herbs in cold-nature and 20 herbs in hot-nature. Antioxidant capacities were evaluated by the following methods: scavenging ABTS•(+) (2, 2'azinobis-(3-ethylbenz-thiazoline-6-sulfonic acid), scavenging O2•(-), and Ferric-reducing antioxidant power (FRAP). The effects on inhibition of mitochondrion lipid peroxidation were determined by measuring the formation of TBARS (Thiobarbituric acid reactive substrates). Total phenolics and flavonoids were estimated by Folin-Ciocalteu and NaNO2-Al(NO3)3-NaOH colorimetric methods. Interestingly, the cold-nature herbs displayed higher antioxidant activities than the hot-nature ones, corresponding to nearly three-fold higher total phenolic contents in the cold-nature herbs. Moreover, the antioxidant activities correlated linearly with the levels of total phenolics for both cold-nature and hot-nature herbs, but only with the levels of total flavonoids for the hot-nature herbs. The results suggested that the phenolic compounds, but not the flavonoids, play the major role in antioxidant capacities of the cold-nature herbs. These findings could shed new lights on the study the theory of Tibetan medicine.

Abstract Juniperus pingii var. wilsonii has been traditionally used in Tibetan medicine for the treatment of inflammatory diseases. In the present study, J. pingii var. wilsonii polysaccharides (JPWP), with high content of d ‑galacturonic acid, showed potent anti-complementary activity in vitro and significantly attenuated acute lung injury (ALI) induced by H1N1 influenza virus in vivo through reducing the inflammatory responses, alleviating oxidative stress and inhibiting the activation of complement. Thus, anti-complementary activity-guided fractionation of JPWP led to the isolation of an acidic homogeneous polysaccharide, JPWP-PS, whose structure was further elucidated by acid hydrolysis, PMP derivation, methylation and NMR analysis. JPWP-PS had potent anti-complementary activity with the CH 50 value of 0.073 ± 0.009 mg/mL, and was characterized by the residues of T-Ara f -(1→, →3)-Ara f -(1→, →3,5)-Ara f -(1→, →3)-Gal p -(1→ and →4)-Gal p A-(1→. Graphical abstract Unlabelled Image Highlights • Juniperus pingii var. wilsonii polysaccharides (JPWP) improved survival rate of H1N1 virus infected mice. • JPWP treated acute lung injury via inhibiting inflammatory responses, oxidative stress and activation of complement. • A homogeneous acidic polysaccharide with potent anti-complementary activity was isolated from JPWP. [ABSTRACT FROM AUTHOR]

<br>Display Omitted<br>• Mercuric chloride-human serum albumin adduct causes hormesis in N9 microglia cells. • Hormesis was implemented through ERK/MAPKs and JAK/STAT3 signaling pathways. • 15 ng/mL of Hg-HSA was close to a NOAEL for N9 cells and this dose may be beneficial. • Hg2+ could form stable coordination structures in both Asp249 site and Cys34 site of HSA.<br>Mercury chloride (HgCl2), a neurotoxicant that cannot penetrate the blood-brain barrier (BBB). Although when the BBB are got damaged by neurodegenerative disorders, the absorbed HgCl2, mainly in form of Hg (II)-serum albumin adduct (Hg-HSA) in human plasma, can penetrate BBB and affect central nervous system (CNS) cells. Current study planned to evaluate the effect of Hg-HSA on the physiological function of N9 microglial cells. At low dosage (15 ng/mL) of Hg-HAS, the observed outcomes was: promoted cell propagation, Nitric Oxide (NO) and intracellular Ca2+ levels enhancement, suppressed the release of TNF-α and IL-1β and inhibited cell proliferation. At high dosage (15 μg/mL) we observed decline in NO and intracellular Ca2+ levels, and increment in the release of TNF-α and IL-1β. These biphasic effects are similar to hormesis, and the hormesis, in this case, was executed through ERK/MAPKs and JAK/STAT3 signaling pathways. Study of quantum chemistry revealed that Hg2+ could form stable coordination structures in both Asp249 and Cys34 sites of HSA. Although five-coordination structure in Asp249 site is more stable than four-coordination structure in Cys34 site but four-coordination structure is formed easily in-<b>vivo</b> in consideration of binding-site position in spatial structure of HSA.

Barley seedlings are rich in flavones that can have positive effects on people with antihypoxia and antifatigue. Lutonarin and saponarin are two major flavonoid glycosides that have unique structures in barley seedlings. This study presents a new approach for the preparation of lutonarin and saponarin from barely seedlings by membrane separation technology and preparative high-performance liquid chromatography. Preparative conditions of these two flavonoid glycosides by membrane separation technology were studied using response surface methodology. Under the optimized conditions, the total contents of these two flavonoid glycosides amounts to 17.0%.

In order to efficiently control the quality of the Tibetan medicine Gentianae Szechenyii Flos, the quality standard was established in this study. The tests of water content, total ash and ethanol-soluble extractives of the crude drugs were carried out based on the methods recorded in appendix of Chinese Pharmacopeia (2010 edition, volume 1). The TLC method was established by using reference drug and gentiournoside A as reference substance, and a mixture of ethyl acetate-methanol-water-formic acid (7: 1.5: 1: 0.2) as the developing solvent system on silica gel G TLC plate. The content of gentiournoside A was assayed by HPLC on a Ultimate XB-C18 (4.6 mm x 250 mm, 5 μm) column, using methanol-water (0.02% phosphoric acid) (52:48) as the mobile phase at a flow rate of 1.0 mL x min(-1). The column temperature is 25 degrees C and the detection wavelength is at 240 nm. As a result, gentiournoside A and the other constituents were separated and presented the same fluorescence light comparing with the reference substance on TLC detected under the UV light(366 nm). The methodology validation for the assay of gentiournoside A showed that it was in a good linear correlation in the range of 10.01-400.32 mg x L(-1) with the regression equation of Y = 1 539.5X - 33.339 (r = 0.999 7), and the average recovery was 99.68% (RSD 1.92%). The mass fractions of gentiournoside A, water content, ethanol-soluble extractives of 19 batches samples were varied in the ranges of 14.48-31.51 mg x g(-1), 11.25% -12.74% and 24.21% - 31.60%, respectively, and total ash was 4.64% - 6.12% detected from 10 batches samples. The recommended standards of quantitative indexes are that the mass fractions of gentiournoside A and extractives are not less than 15.0 mg x g(-1) (1.5%) and 21.0%, respectively; the water and total ash are not more than 13.0% and 6.0%, respectively.

Gentianae Urnulae Herba, dried whole herb of Gentiana urnula,is a commonly used Tibetan medicine. However, only the character identification is used as quality control standard officially at present. As a part of project for the Chinese Pharmacopoeia (2015 edition), the quality standard of this species was established in this study. The tests of water content, total ash, acid-insoluble ash and ethanol-soluble extractives of the crude drugs were carried out following the methods recorded in appendix of Chinese Pharmacopeia (2010 edition, volume 1). The TLC identification method was established by using gentiournoside A as reference substance, and a mixture of ethyl acetate-methanol-water-formic acid(7:1. 5:1: 0. 2) as the developing solvent system on silica gel G TLC plate. The content of gentiournoside A was assayed by HPLC on an Agilent Zorbax SB-C18 (4.6 mm x 250 mm,5 μm) column, using acetonitrile-water (0.1% phosphoric acid) (26:74) as the mobile phase at a flow rate of 1.0 mL x min(-1). The column temperature is at 30 degrees C and the detection wavelength is at 240 nm. As a result, gentiournoside A and the other constituents were separated and presented the same fluorescence light comparing with the reference substance on TLC detected under the UV light(366 nm). The methodology validation for the assay of gentiournoside A showed that it was in a good linear correlation in the range of 0.009 95-0.398 g x L(-1) with the regression equation of Y = 1 467.1X +41.407(r = 0.999 9), and the average recovery was 98. 3% (RSD 2.2%). The mass fractions of gentiournoside A, water content, ethanol-soluble extractives of 15 batches samples were varied in the ranges of 0.175% -1.83%, 8.60% - 9.93% and 29.2% - 35.2%, respectively. Total ash and acid-insoluble ash were 10.2% - 17.2% and 5.26% - 10.8% detected from 10 batches samples. The recommended standards of quantitative indexes are that the mass fractions of gentiournoside A and extractives are not less than 0.80% and 26.0%, respectively; the water, total ash and acid-insoluble ash are not more than 12.0%, 15.0% and 8.0%, respectively.

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.