A rapid, sensitive, and selective precolumn derivatization method for the simultaneous determination of eight thiophenols using 3-(2-bromoacetamido)-<i>N</i>-(9-ethyl-9<i>H</i>)-carbazol as a labeling reagent by high-performance liquid chromatography with fluorescence detection has been developed. The labeling reagent reacted with thiophenols at 50°C for 50 min in aqueous acetonitrile in the presence of borate buffer (0.10 mol/L, pH 11.2) to give high yields of thiophenol derivatives. The derivatives were identified by online postcolumn mass spectrometry. The collision-induced dissociation spectra for thiophenol derivatives gave the corresponding specific fragment ions at <i>m/z</i> 251.3, 223.3, 210.9, 195.8, and 181.9. At the same time, derivatives exhibited intense fluorescence with an excitation maximum at λ<sub>ex</sub> = 276 nm and an emission maximum at λ<sub>em</sub> = 385 nm. Excellent linear responses were observed for all analytes over the range of 0.033-6.66 μmol/L with correlation coefficients of more than 0.9997. Detection limits were in the range of 0.94-5.77 μg/L with relative standard deviations of less than 4.54%. The feasibility of derivatization allowed the development of a rapid and highly sensitive method for the quantitative analysis of trace levels of thiophenols from some rubber products. The average recoveries (<i>n</i> = 3) were in the range of 87.21-101.12%.
Meconopsis horridula is one of alpine plants belonging to family Papaveraceae, mainly distributed in Himalaya Range area. M. horridula is a rare alpine flower, and is a kind of traditional Tibetan medicine, which has been included in more than 40 compound formulae, having efficacies of clearing away heat and alleviating pain, activating blood circulation to remove stasis, traditionally used for the treatment of fractures, injuries, and chest and back pains. Modern research shows that the whole plant of M. horridula contains alkaloids, flavonoids, and terpenes, and its pharmacological activities including antitumor, antivirus and myocardial protection etc. However, due to various factors, the current research of M.horridula still faces many challenges. This paper summaries herein a progress of MH on its ecological resources, traditional uses, and studies on chemical constituents and pharmacological effects, hopefully to provide a useful reference for the ecological protection and applications.
<br>Display Omitted<br>• 4′-Carbonyl chloride rosamine was synthesized and used for NTs by UHPLC-MS/MS. • <b>In situ</b> UA-DDLLME was reported for the simultaneous determination of AANTs and MANTs. • The method was sensitive, selective, low matrix effect, speedy and eco-friendly. • A new analytical tool in diagnosis of AD-related disease.<br>Neurotransmitters (NTs) may play an important role in neurodegenerative disorders such as Alzheimer’s disease (AD). In order to investigate the potential links, a new simple, fast, accurate and sensitive analytical method, based on <b>in situ</b> ultrasound-assisted derivatization dispersive liquid-liquid microextraction (<b>in situ</b> UA-DDLLME) coupled with ultra high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS), has been developed and validated. The quantitation of amino acid neurotransmitters (AANTs) and monoamine neurotransmitters (MANTs) in urine of AD rats were performed in this work. The <b>in situ</b> UA-DDLLME procedure involved the rapid injection of the mixture of low toxic 4-bromoanisole (extractant) and acetonitrile (dispersant), which containing the new designed and synthesized 4′-carbonyl chloride rosamine (CCR) as derivatization reagent, into the aqueous phase of real sample and buffer. Under the selected conditions, the derivatization and microextraction of analytes were simultaneously completed within 1 min. Good linearity for each analyte (R > 0.992) was observed with low limit of detections (LODs, S/N > 3). Moreover, the proposed method was compared with direct detection or other reported methods, and the results showed that low matrix effects and good recoveries results were obtained in this work. Taken together, <b>in situ</b> UA-DDLLME coupled with UHPLC-MS/MS analysis was demonstrated to be a good method for sensitive, accurate and simultaneous monitoring of AANTs and MANTs. This method would be expected to be highly useful in AD diseases’ clinical diagnostics and may have potential value in monitoring the efficacy of treatment.
A new labeling reagent, 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP), coupling with liquid chromatography (LC) with electrospray ionization mass spectrometry (ESI-MS) for the detection of carbohydrates from a famous Tibetan medicine is reported. Carbohydrates were derivatized to their bis-NMP-labeled derivatives. The method, in conjunction with a gradient elution, offered a baseline resolution of carbohydrate derivatives on a reversed phase Hypersil ODS-2 column. The carbohydrates such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose, and fucose could be successfully detected by UV and ESI-MS. Derivatives showed intense protonated molecular ion at m/z [M + H]+ in positive ion mode. The mass to charge ratios of characteristic fragment ions at m/z 473.0 could be used for the accurately qualitative identification of carbohydrates; this characteristic fragment ion was from the cleavage of C2-C3 bond in the carbohydrate chain giving the specific fragment ions at m/z [MH-CmH2m+1Om-H2O]+ for pentose, hexose, and glyceraldehydes, and at m/z [MH-CmH2m-1Om+1-H2O]+ for alduronic acids, such as galacturonic acid and glucuronic acid (m = n - 2, n is carbon atom number of carbohydrate). Compared with the traditional 1-phenyl-3-methyl-5-pyrazolone (PMP) reagent, currently synthesized NMP show the advantage of higher sensitivity to carbohydrate compounds with UV and ESI-MS detection.
The aqueous extracts i.p. of Dracocephalum tanguticum Maxim (DtM), a Tibetan medicine, prolong sighificantly decapitaion-induced gasping duration in mice and the survival time of mice ligated bilateral carotid (P > 0.01). DtM prolong also the primal gasping in mice after injecting the air into the coccygeal vein (P > 0.01) and the survival time in mice poisoned by Lidocaine (P > 0.05). In addition, DtM is possessed of protecting against the pathologic lession of brain in rats under stimulating high altitude hypoxic condition. The results suggest that DtM has a antianoxic effects on mice.
This study was to investigate the anti-diabetic effects and molecular mechanisms of Tang-Kang-Fu-San (TKFS), a traditional Tibetan medicine, in treating type 2 diabetes mellitus of spontaneous diabetic db/db mice. Firstly HPLC fingerprint analysis was performed to gain the features of the chemical compositions of TKFS. Next different doses of TKFS (0.5 g/kg, 1.0 g/kg, and 2.0 g/kg) were administrated via oral gavage to db/db mice and their controls for 4 weeks. TKFS significantly lowered hyperglycemia and ameliorated insulin resistance (IR) in db/db mice, indicated by results from multiple tests, including fasting blood glucose test, intraperitoneal insulin and glucose tolerance tests, fasting serum insulin levels and homeostasis model assessment of IR analysis as well as histology of pancreas islets. TKFS also decreased concentrations of serum triglyceride, total and low-density lipoprotein cholesterol, even though it did not change the mouse body weights. Results from western blot and immunohistochemistry analysis indicated that TKFS reversed the down-regulation of p-Akt and p-AMPK, and increased the translocation of Glucose transporter type 4 in skeletal muscles of db/db mice. In all, TKFS had promising benefits in maintaining the glucose homeostasis and reducing IR. The underlying molecular mechanisms are related to promote Akt and AMPK activation and Glucose transporter type 4 translocation in skeletal muscles. Our work showed that multicomponent Tibetan medicine TKFS acted synergistically on multiple molecular targets and signaling pathways to treat type 2 diabetes mellitus.
The aim of this study was to investigate the antidiabetic effects of a Tibetan medicine, Tang-Kang-Fu-San (TKFS), on experimental type 2 diabetes mellitus (T2DM) rats and to explore its underlying mechanisms. Firstly two major chemical compositions of TKFS, gallic acid and curcumin, were characterized by HPLC fingerprint analysis. Next T2DM in rats was induced by high-fat diet and a low-dose streptozotocin (STZ 35 mg/kg). Then oral gavage administration of three different doses of TKFS (0.3 g/kg, 0.6 g/kg, and 1.2 g/kg) was given to T2DM rats. Experimental results showed that TKFS dramatically reduced the levels of fasting blood glucose, fasting blood insulin, triglyceride, total cholesterol, LDL cholesterol, and HDL cholesterol, even though it did not alter the animal body weight. The downregulation of phosphorylation-AKT (p-AKT) and glucose transporter-4 (GLUT4) in skeletal muscle of T2DM rats was restored and abnormal pathological changes in pancreas tissues were also improved. Our work showed that TKFS could alleviate diabetic syndromes, maintain the glucose homeostasis, and protect against insulin resistance in T2DM rats, and the improvement of AKT phosphorylation and GLUT4 translocation in skeletal muscle would be one of its possible underlying mechanisms.
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.
An efficient method for the screening and isolation of potent antioxidants from a tibetan medicinal plant by employing online HPLC--DPPH assay combined HSCCC has been successfully established. Six major constituents: boschnaloside (1), alyssonoside (2), leucosceptoside A (3), isoverbascoside (4), leucosceptoside B (5) and verbascoside (6) were isolated and purified from the water extract by HSCCC using ethyl acetate-nbutanol- water as two-phase solvent system. The results indicated that the combination of the online HPLC-- DPPH assay with HSCCC could be suitable for the screening and separation of antioxidant compounds from extract of this plant or other medicine plants. [ABSTRACT FROM AUTHOR]
The biosynthesis of nanoparticles in bioreactors using microbial, plant, or animal cells is at the forefront of nanotechnology. We demonstrated for the first time that luminescent, water-soluble ZnO nanocrystals (bio-ZnO NCs) can be spontaneously biosynthesized in the mammalian blood circulation, not in cells, when animals were fed with Zn(CH3COO)2 aqueous solution. Serum albumin, rather than metallothioneins or glutathione, proved to play the pivotal role in biosynthesis. The bio-ZnO NCs were gradually taken up in the liver and degraded and excreted in the urine. Thus, we propose that in mammals such as rodents, bovinae, and humans, excess metal ions absorbed into the cardiovascular system via the intestine can be transformed into nanoparticles by binding to serum albumin, forming a "provisional metal-pool", to reduce the toxicity of free metal ions at high concentration and regulate metal homeostasis in the body. Furthermore, the bio-ZnO NCs, which showed favorable biocompatibility, were functionalized with the anticancer drug daunorubicin and effectively achieved controlled drug release mediated by intracellular glutathione in tumor xenograft mice.
Zuota is regarded as the king of Tibetan medicine. However, due to the confidentiality of this precious medicine, the scientific characterization of Zuota is very scarce, which limits the pharmacology and biosafety studies of Zuota. Herein, we collected four different Zuota samples from Tibet, Qinghai, Gansu, and Sichuan and characterized them by multiple techniques. Our results showed that Zuota was mainly an inorganic mixture of HgS, sulfur, and graphite. Morphologically, Zuota samples were composed of nanoparticles, which further aggregated into microsized particles. Chemically, the majorities of Zuota were S and Hg (in the forms of HgS and pure sulfur). All samples contained pure sulfur with orthorhombic crystalline. Zuota from Qinghai province had different HgS crystalline, namely, hexagonal crystalline. The others were all face-centered cubic crystalline. Carbon in Zuota NPs was in the form of graphite. The implication to future studies of Zuota was discussed.
Zuota is regarded as the king of Tibetan medicine. However, due to the confidentiality of this precious medicine, the scientific characterization of Zuota is very scarce, which limits the pharmacology and biosafety studies of Zuota. Herein, we collected four different Zuota samples from Tibet, Qinghai, Gansu, and Sichuan and characterized them by multiple techniques. Our results showed that Zuota was mainly an inorganic mixture of HgS, sulfur, and graphite. Morphologically, Zuota samples were composed of nanoparticles, which further aggregated into microsized particles. Chemically, the majorities of Zuota were S and Hg (in the forms of HgS and pure sulfur). All samples contained pure sulfur with orthorhombic crystalline. Zuota from Qinghai province had different HgS crystalline, namely, hexagonal crystalline. The others were all face-centered cubic crystalline. Carbon in Zuota NPs was in the form of graphite. The implication to future studies of Zuota was discussed.
Zuota is regarded as the king of Tibetan medicine. However, due to the confidentiality of this precious medicine, the scientific characterization of Zuota is very scarce, which limits the pharmacology and biosafety studies of Zuota. Herein, we collected four different Zuota samples from Tibet, Qinghai, Gansu, and Sichuan and characterized them by multiple techniques. Our results showed that Zuota was mainly an inorganic mixture of HgS, sulfur, and graphite. Morphologically, Zuota samples were composed of nanoparticles, which further aggregated into microsized particles. Chemically, the majorities of Zuota were S and Hg (in the forms of HgS and pure sulfur). All samples contained pure sulfur with orthorhombic crystalline. Zuota from Qinghai province had different HgS crystalline, namely, hexagonal crystalline. The others were all face-centered cubic crystalline. Carbon in Zuota NPs was in the form of graphite. The implication to future studies of Zuota was discussed.
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>
The chemical investigation of ethanolic extract from Swertia mussotii Franch. has resulted in the isolation of 11 compounds which were identified as Orcinol-β-D-glucoside (1), Shamimin (2), Mangiferin (3), Decussatin (4), Bellidifolin (5), Desmethylbellidifolin (6), Protocatechuic acid (7), 1,7-Dihydroxy-3,8-dimethoxyxanthone (8), 1,8-Dihydroxy-3,5-dimethoxyxanthone (9), 1-Hydroxy-3,5-dimethoxyxanthone (10), Telephioidin (11). The chemical structures of these compounds were identified by a combination of spectroscopic analysis and a comparison with those reported in literature. Among them, compounds 1, 2, 7 and 11 were isolated from the genus Swertia for the first time. Moreover, the chemotaxonomic significance of these compounds was summarised. The chemotaxonomic study suggests that there is a close chemotaxonomic relationship between S. mussotii and other species of Swertia, such as S. punicea, S. macrosperma, S. japonica, S. phragmitiphylla, S. chirayita, S. cordata and S. binchuanensis, with presence of compounds 3~6, 8~10. The xanthones and their glycosides may sever as important chemotaxonomic markers of Swertia genus.
The chemical investigation of ethanolic extract from Swertia mussotii Franch. has resulted in the isolation of 11 compounds which were identified as Orcinol-β-D-glucoside (1), Shamimin (2), Mangiferin (3), Decussatin (4), Bellidifolin (5), Desmethylbellidifolin (6), Protocatechuic acid (7), 1,7-Dihydroxy-3,8-dimethoxyxanthone (8), 1,8-Dihydroxy-3,5-dimethoxyxanthone (9), 1-Hydroxy-3,5-dimethoxyxanthone (10), Telephioidin (11). The chemical structures of these compounds were identified by a combination of spectroscopic analysis and a comparison with those reported in literature. Among them, compounds 1, 2, 7 and 11 were isolated from the genus Swertia for the first time. Moreover, the chemotaxonomic significance of these compounds was summarised. The chemotaxonomic study suggests that there is a close chemotaxonomic relationship between S. mussotii and other species of Swertia, such as S. punicea, S. macrosperma, S. japonica, S. phragmitiphylla, S. chirayita, S. cordata and S. binchuanensis, with presence of compounds 3~6, 8~10. The xanthones and their glycosides may sever as important chemotaxonomic markers of Swertia genus.
The genus Gentiana is the largest in the Gentianaceae family with ca. 400 species. However, with most species growing on the Qinghai-Tibet plateau, the processes of adaptive evolution and speciation within the genus is not clear. Also, the genomic analyses could provide important information. So far, the complete chloroplast (cp) genome data of the genus are still deficient. As the second and third sequenced members within Gentianaceae, we report the construction of complete cp sequences of Gentiana robusta King ex Hook. f. and Gentiana crassicaulis Duthie ex Burk., and describe a comparative study of three Gentiana cp genomes, including the cp genome of Gentiana straminea Maxim. published previously. These cp genomes are highly conserved in gene size, gene content, and gene order and the rps16 pseudogene with exon2 missing was found common. Three repeat types and five SSR types were investigated, and the number and distribution are similar among the three genomes. Sixteen genome divergent hotspot regions were identified across these cp genomes that could provide potential molecular markers for further phylogenetic studies in Gentiana. The IR/SC boundary organizations in Gentianales cp genomes were compared and three different types of boundaries were observed. Six data partitions of cp genomes in Gentianales were used for phylogenetic analyses and different data partitions were largely congruent with each other. The ML phylogenetic tree was constructed based on the fragments in cp genomes commonly available in 33 species from Lamiids, including 12 species in Gentianales, 1 in Boraginaceae, 10 in Solanales, and 10 in Lamiales. The result strongly supports the position of Boraginaceae (Ehretia acuminata) as the sister of Solanales, with the bootstrap values of 97 %. This study provides a platform for further research into the molecular phylogenetics of species in the order Gentianales (family Gentianaceae) notably in respect of speciation and species identification.;
In this article the classics textual research to the origin of "Zha-xun" was carried out, the ethnobotanical research methods, the origin of visits, key informant interviews, sample collection and textual research were applied in the research. The results showed that the hypothesis of Zha-xun"s origin mainly included "source of mine", "source of feces", "source of monkey menstrual blood" in China. There were "source of fossil", "source of the plant secretion" abroad. The authors had interviewed the villagers at origin, herbalists, Tibetan doctors, herb dealers, foreign scholars for a total of 18 people, and collecting 45 batches medicinal materials. According to ancient Tibetan classics textual and Tibetan medicine doctors' views, medicinal materials were divided into the genuine and the substitutes. The genuine was identified as ancient so-called "iron" type "Zha-xun", and the substitute was fecal pellet bonding briquette. According to the field survey and literature research, "source of fossil" more in line with substance of Zha-xun was derived from the rock. As the results, the author believed that Zha-xun was the mixture of organic fossils from the rock seepage with flying squirrel, pika feces. So it is needed to be set up Zha-xun classification standard to evaluate the quality of medicinal materials. Meanwhile, it was necessary to further clarify fecal pellet substitute rationality. Above all, this article clarified the status of the use of Tibetan medicine-"Zha-xun", and laid the foundation of species systematics and quality standards research of "Zha-xun".
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