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The regulation of postprandial blood glucose (PBG) levels is an effective therapeutic method to treat diabetes and prevent diabetes-related complications. Resveratroloside is a monoglucosylated form of stilbene that is present in red wine, grapes, and several traditional medicinal plants. In our study, the effect of resveratroloside on reducing PBG was studied in vitro and in vivo. In comparison to the starch treatment alone, the oral administration of resveratroloside-starch complexes significantly inhibited the PBG increase in a dose-dependent pattern in normal and diabetic mice. The PBG level treated with resveratrol (30 mg/kg) was not lower than that of resveratroloside. Further analyses demonstrated that resveratroloside strongly and effectively inhibited α-glucosidase, with an 50% inhibitory concentration value of 22.9 ± 0.17 μM, and its inhibition was significantly stronger than those of acarbose and resveratrol (264 ± 3.27 and 108 ± 2.13 μM). Moreover, a competitive inhibition mechanism of resveratroloside on α-glucosidase was determined by enzyme kinetic assays and molecular docking experiments. The molecular docking of resveratroloside with α-glucosidase demostrated the competitive inhibitory effect of resveratroloside, which occupies the catalytic site and forms strong hydrogen bonds with the residues of α-glucosidase. Resveratrol was also determined to be a competitive inhibition mechanism on α-glucosidase by enzyme kinetic assays and molecular docking experiments. This study suggested that resveratroloside had the ability to regulate PBG levels and can be considered a potential agent for the treatment of diabetes mellitus.

<i>Saussurea laniceps</i> (Compositae), commonly known as “cotton-headed snow lotus”, is the most effective “snow lotus” used in both Tibetan and Chinese folk medicine. It performs outstandingly in treating rheumatoid arthritis, which mainly is credited for its anti-inflammatory and anti-nociceptive efficacy, as explained by modern pharmacological studies. Extracts of the herb, including umbelliferone and scopoletin, exert such effects in various in vivo and in vitro studies. Besides the two chemicals above, more than 100 organic compounds have been found in <i>S. laniceps</i>, and 58 of them are presented here in molecular structure, including cynaropicrin, mokko lactone, apigenin, acacetin, and luteolin, all contributing to different bioactivities, such as analgesic, antioxidant, immunomodulatory, anti-microbial and anticancer effects. We provide a natural product library of <i>S. laniceps</i>, giving inspirations for structure modification and bioactivity-oriented screening, enabling sustainable use of this valuable plant. The ethnomedical applications and pharmacological discoveries are compared and crosslinked, revealing modern evidence for traditional usages. Despite that <i>S. laniceps</i> is a representative “snow lotus” herb, its material medica records and clinical applications are complicated; there is considerable confusion with the different snow lotuses in the academic community and on the market. This review also aims at clearing such confusion, and improving quality assessment and control of the herb. To better utilize the valuable plant, further comparison among the chemical constitutions, pharmacological activities and therapeutic mechanisms of different snow lotuses are needed.

Highland barley is one of the most important industrial crops in Tibetan plateau. Previous research indicated that highland barley has many medical functions. In this work, the antibacterial abilities of highland barley were investigated. The protein solutions hydrolyzed by trypsin for 4 h exhibited the highest antibacterial activity. An antibacterial peptide, barleycin, was screened and purified by magnetic liposome extraction combining with the protein profiles of reversed-phase high-performance liquid chromatography (RP-HPLC). Structure, characterization, and safety evaluation of barleycin were further investigated. Amino acids sequence was determined as Lys-Ile-Ile-Ile-Pro-Pro-Leu-Phe-His by N-sequencing. Circular dichroism spectra indicated the a-helix conformation of barleycin. The activity spectrum included <i>Bacillus subtilis, Staphylcoccus aureus, Listeria innocua and Escherichia coli</i> and the MICs were from 4 to 16 μg/mL. Safety evaluations with cytotoxicity and hemolytic suggested this antibacterial peptide could be considered as safe at MICs. Finally, mode of action of barleycin on sensitive cells was primarily studied. The results suggested the damage of cell membrane.

Four iridoid glucosides, shanzhiside methyl ester, phloyoside II, chlorotuberside, and penstemonoside, were isolated and purified from an herbal medicinal plant for the first time by high-speed counter-current chromatography (HSCCC) using a two-phase solvent system composed of ethyl acetate-n-butanol-water (5:14:12, v/v/v). A total of 37mg of shanzhiside methyl ester, 29mg of phloyoside II, 27mg of chlorotuberside, and 21mg of penstemonoside with the purity of 99.2%, 98.5%, 97.3%, and 99.3%, respectively, were obtained in one-step separation within 4h from 150mg of crude extract. To the best of our knowledge, this is the first report of separation and purification of iridoid glucosides from natural sources by HSCCC. The chemical structures of all the four compounds were identified by ESI-MS, (1)H NMR, and (13)C NMR.

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.

Six compounds including two n-butyrophenone isomers and two stibene isomers were obtained from Rheum tanguticum Maxim. Two n-butyrophenone isomers with a separation factor of 1.14 were successfully separated by recycling high-speed counter-current chromatography after ten cycles. Two stibene isomers were successfully separated by preparative high-performance liquid chromatography. High-performance liquid chromatography analysis showed that the purities of the compounds were all over 98%. These compounds were identified as lindleyin, isolindleyin, resveratrol-4'-O-(2″-O-galloyl)-glucopyranoside, resveratrol-4'-O-(6''-O-galloyl)-glucopyranoside, emodin 1-O-β-d-glucoside, and 3,5-dihydroxy-4'-methoxystilbene-3-O-β-d-glucopyranoside. The results indicated that recycling high-speed counter-current chromatography and preparative high-performance liquid chromatography could be effective combination for the preparation of bioactive compounds from Rheum tanguticum Maxim.

Anthraquinone glycosides, such as chrysophanol 1-O-β-d-glucoside, chrysophanol 8-O-β-d-glucoside, and physion 8-O-β-d-glucoside, are the accepted important active components of Rheum tanguticum Maxim. ex Balf. due to their pharmacological properties: antifungal, antimicrobial, cytotoxic, and antioxidant activities. However, an effective method for the separation of the above-mentioned anthraquinone glycosides from this herb is not currently available. Especially, greater difficulty existed in the separation of the two isomers chrysophanol 1-O-β-d-glucoside and chrysophanol 8-O-β-d-glucoside. This study demonstrated an efficient strategy based on preparative high-performance liquid chromatography and high-speed countercurrent chromatography for the separation of the above-mentioned anthraquinone glycosides from Rheum tanguticum Maxim.ex Balf.

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.

Simultaneous detection of oleanolic acid and ursolic acid in rat blood by in vivo microdialysis can provide important pharmacokinetics information. Microwave-assisted derivatization coupled with magnetic dispersive solid phase extraction was established for the determination of oleanolic acid and ursolic acid by liquid chromatography tandem mass spectrometry. 2'-Carbonyl-piperazine rhodamine B was first designed and synthesized as the derivatization reagent, which was easily adsorbed onto the surface of Fe3O4/graphene oxide. Simultaneous derivatization and extraction of oleanolic acid and ursolic acid were performed on Fe3O4/graphene oxide. The permanent positive charge of the derivatization reagent significantly improved the ionization efficiencies. The limits of detection were 0.025 and 0.020 ng/mL for oleanolic acid and ursolic acid, respectively. The validated method was shown to be promising for sensitive, accurate, and simultaneous determination of oleanolic acid and ursolic acid. It was used for their pharmacokinetics study in rat blood after oral administration of Arctiumlappa L. root extract.

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.

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.

Qumazi is a commonly used Tibetan medicine. With a long history, it can be found in the Four Medical Tantras written by gYu-thog rNying-ma Yon-tan mGon-po since the 8th century AD. Qumazi grows in mudflats and fields, including species growing in highlands, lowlands, mountains and farmlands. According to records in Crystal Beads Materia Medica, it features green sword-shaped leaves, thin stems with red veins, inserted panicles, white chicken-like flowers and copper needle row-like roots. However, there are many inconsistent morphological descriptions for Qumazi plants in many Chinese versions of Tibetan medicine books. In this article, after studying ancient and modern Tibetan medicine books, consulting experts and conducting surveys, the authors confirmed that Qumazi belongs to Rheum of Polygonaceae, including Rheum nobile Hook. f. et. Thoms, R. globulosum Gage, R. alexandrae Hook. f. et. Thoms, R. pumilum Maxim and R. delavayi Franch. In some regions, Qumazi is substituted by R. spiciforme Royle and R. przewalskyi Losinsk. After the Chinese version of Qinghai-Tibet Plateau Drug Illustrations was published in 1972, Qumazi has been miswritten as P. sibiricum Laxm in many Chinese versions of Tibetan medicine books, perhaps because P. sibiricum Laxm has many similar features with Qumazi as described in Crystal Beads Materia Medica and then is mistranslated from Tibetan to Chinese versions. According to records, Qumazi can reduce edema and is mainly applied to treat the minamata disease in clinic.

<br>Display Omitted<br>• Three new monoterpene glycosides (<b>1</b>-<b>3</b>) were isolated from <b>Sibiraea laevigata</b> (L.) Maxim. • Fourteen known compounds (<b>4</b>-<b>17</b>) were also obtained from the title plant. • All of the isolated compounds were evaluated for their anti-oxidant and α-glucosidase inhibitory activities. • Compounds <b>7</b> and <b>17</b> exhibited α-glucosidase inhibitory effect with IC50 values of 220.0 and 113.0 μM, respectively.<br>Three new compounds, 3,7-dimethy-7-methoxy-3-octene-5-one-1-<b>O</b>-<b>β</b>-d-glucopyranoside (1), 3,7-dimethy-7-methoxy-3(<b>Z</b>)-octene-5-one-1-<b>O</b>-<b>β</b>-d-glucopyranoside (2) and 3,7-dimethy-3-hydroxy-6-octene-5-one-1-<b>O</b>-<b>β</b>-d-glucopyranoside (3), together with fourteen known compounds (4-17) were isolated from the leaves and shoots of <b>S. laevigata</b>. The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis, including one- and two-dimensional NMR, as well as mass spectral data. All isolates were evaluated for their α-glucosidase inhibitory and antioxidant activities. The results demonstrated that 3,7-dimethyl-3(Z),6-ocatdien-5-one-1-<b>O</b>-<b>β</b>-d-glucoside (7) and sitosteryl <b>β</b>-d-glucoside (17) exhibited α-glucosidase inhibitory effects with IC50 values of 220.0 and 113.0 μM, respectively.

Traditional Chinese medicine is important for discovery of drug precursors. However, information about trace chemical composition of them is very limited due to the lack of appropriate enrichment and chromatographic purification methods In our work, A. kansuensis was taken as an example, a novel two-dimensional reversed-phase/hydrophilic interaction liquid chromatography coupled with UniElut C18AEX solid-phase extraction re-enrichment method based on anti-inflammatory bioactivity-guided assay was developed for gathering and purifying trace β-carboline alkaloids with high purity from the ethyl acetate extract of A. kansuensis. Extraction with ethyl acetate as the first enrichment method, then, a UniElut C18AEX column was employed to re-enrich trace fraction which was hardly detected by diode array detector during high performance liquid chromatography analysis, eighteen grams of UniElut C18AEX was used as sorbent material to pack a 60mL pipette tip for the extraction of β-carboline alkaloids from 100mL of ethyl acetate sample. The whole extraction process was finished in 10min, and the volume of eluent used was only 120mL. The enriching fraction (100mg) was used for the following two-dimensional purification. First-dimensional preparation was carried on a RP-Megress-C18 prep column, and four anti-inflammatory fractions were obtained from the 100mg re-enriching sample with a recovery of 66.9%. A HILIC-XAmide prep column was selected for the second dimensional preparation. Finally, two pair of analogue β-carboline alkaloids and one other β-carboline alkaloid were purified from A. kansuensis. The purity of the isolated compounds was ≫>98%, which indicated that the method was efficient to re-enrich and manufacture single trace β-carboline alkaloids with high purity from A. kansuensis. Additionally, this method showed great potential to serve as a good example for the purification and enrichment of analogue structure anti-inflammation carboline alkaloids from other plant materials.

Traditional Tibetan medicine is important for discovery of drug precursors. However, information about the chemical composition of traditional Tibetan medicine is very limited due to the lack of appropriate chromatographic purification methods. In the present work, A. kansuensis was taken as an example and a novel two-dimensional reversed-phase/hydrophilic interaction liquid chromatography(HILIC) method based on on-line HPLC-DPPH bioactivity-guided assay was developed for the purification of analogue antioxidant compounds with high purity from the extract of A. kansuensis. Based on the separation results of many different chromatographic stationary phases, the first-dimensional (1D) preparation was carried on a RP-C18HCE prep column, and 2 antioxidant fractions were obtained from the 800mg crude sample with a recovery of 56.7%. A HILIC-XAmide prep column was selected for the second-dimensional (2D) preparation. Finally, a novel antioxidant β-carboline Alkaloids (Glusodichotomine AK) and 4 known compounds (Tricin, Homoeriodictyol, Luteolin, Glucodichotomine B) were purified from A. kansuensis. The purity of the compounds isolated from the crude extract was >98%, which indicated that the method built in this work was efficient to manufacture single analogue antioxidant compounds of high purity from the extract of A. kansuensis. Additionally, this method showed great potential in the preparation of analogue structure antioxidant compounds and can serve as a good example for the purification of analogue structure antioxidant carboline alkaloids and flavonoids from other plant materials.

Traditional Tibetan medicine is important for discovery of drug precursors. However, knowledge of the chemical composition of traditional Tibetan medicines is very limited due to the lack of appropriate chromatographic purification methods. In the present work, Salvia prattii was taken as an example, and an off-line hydrophilic interaction liquid chromatography/reversed-phase liquid chromatography preparative method was developed for the purification of phenylpropanoids with high purity from a crude sample of Salvia prattii. Based on the separation results of four different chromatographic stationary phases, the first-dimensional preparation was performed on an XAmide preparative column with the crude sample concentration of 62.0 mg/mL, and five main fractions were obtained from the 12.4 g crude sample with a recovery of 54.8%. An XCharge C18 preparative column was applied in the second-dimensional preparation to further isolate the phenylpropanoids from the redissolved first-dimensional fractions with concentration of approximately 50.0 mg/mL. The purities of the phenylpropanoids isolated from the crude sample of Salvia prattii were higher than 98%, indicating that the method was efficient for the purification of phenylpropanoids with high purity from Salvia prattii. Additionally, this method showed great potential in the preparation of phenylpropanoids and can serve as a good example for the purification of phenylpropanoids from other plant materials.

Two new compounds, deacetylisowortmins A (1) and B (2), were isolated from Talaromyces wortmannii LGT-4. Their structures were established by 1D and 2D NMR spectra, as well as comparison of the experimental and calculated electronic circular dichroism spectra. Monoamine oxidase and acetylcholinesterase inhibitory activities of 1 and 2 were also evaluated.

Two new monoterpenes, 3-(2-oxo-4-methyl-3-pentenyl)furan-5H-2-one (1) and 3-[(2E)-4-hydroxyl-4-methyl-2-pentenyl)]furan-5H-2-one (2), along with eight known compounds (3-10), were isolated from the stalks and infructescence of Sibiraea laevigata. Their structures were elucidated by spectroscopic methods including extensive 1D and 2D NMR techniques. In addition, all of these isolates were evaluated for their cytotoxic and antioxidant activities. The results showed that compounds 5-7 displayed cytotoxicity with IC50 values ranging from 34.8 to 43.2 μg ml-1 against tumor cell lines. Furthermore, 5 and 9 showed antioxidant activities.

Two new prenylated indole diterpenoids, tolypocladins K and L (1 and 2), together with a known analog terpendole L (3), were isolated from the solid fermentation culture of a mine soil-derived fungus Tolypocladium sp. XL115. Their structures and relative configurations were determined by comprehensive spectroscopic data analysis, as well as by comparison of their NMR data with those related known compounds. Compound 3 exhibited remarkable antibacterial activity against Micrococcus luteus with an MIC value of 6.25 μg/mL, and compounds 1 and 3 displayed moderate antifungal activity selectively against tested strains with MIC values of 25-50 μg/mL.

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