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甘肃产三颗针植物中生物碱的测定及分布状态的研究   总被引:7,自引:0,他引:7  
建立梯度洗脱双波长HPLC法同时测定小檗属植物中小檗胺、药根碱、巴马汀、小檗碱含量的方法,并应用该法分析采集于甘肃不同产地、不同品种小檗属植物的茎木、根木、茎皮、根皮样品,研究小檗属植物中生物碱的分布状态,考察其药用价值。小檗胺、药根碱、巴马汀、小檗碱线性范围分别为:0.015~2.56μg(r=0.9998);0.012~2.0μg(r=0.9996);0.010~0.52μg(r=0.9999);0.028~4.74μg(r=0.9998)。结果表明,甘肃不同产地、不同品种,不同部位三颗针植物中生物碱的含量分布有明显的差异。  相似文献   

3.
Essential plants, due to their long presence in human history, their status in culinary arts, their use in medicine and perfume manufacture, belong to frequently examined stock materials in scientific and industrial laboratories. Because of a large number of freshly cut, dried or frozen plant samples requiring the determination of essential oil amount and composition, a fast, safe, simple, efficient and highly automatic sample preparation method is needed.Five sample preparation methods (steam distillation, extraction in the Soxhlet apparatus, supercritical fluid extraction, solid phase microextraction and pressurized liquid extraction) used for the isolation of aroma-active components from Thymus vulgaris L. are compared in the paper. The methods are mainly discussed with regard to the recovery of components which typically exist in essential oil isolated by steam distillation.According to the obtained data, PLE is the most efficient sample preparation method in determining the essential oil from the thyme herb. Although co-extraction of non-volatile ingredients is the main drawback of this method, it is characterized by the highest yield of essential oil components and the shortest extraction time required. Moreover, the relative peak amounts of essential components revealed by PLE are comparable with those obtained by steam distillation, which is recognized as standard sample preparation method for the analysis of essential oils in aromatic plants.  相似文献   

4.
Ferritin is the major iron storage protein in the biosphere. Iron stores of an organism are commonly assessed by measuring the concentration of the protein shell of the molecule in fluids and tissues. The amount of ferritin-bound iron, the more desirable information, still remains inaccessible owing to the lack of suitable techniques. Iron saturation of ferritin is highly variable, with a maximum capacity of 4,500 iron atoms per molecule. This study describes the direct isotopic labeling of a complex metalloprotein in vivo by biosynthesis, in order to measure ferritin-bound iron by isotope dilution mass spectrometry. [57Fe]ferritin was produced by cloning and overexpressing the Phaseolus vulgaris ferritin gene pfe in Escherichia coli in the presence of 57FeCl2. Recombinant ferritin was purified in a fully assembled form and contained approximately 1,000 iron atoms per molecule at an isotopic enrichment of more than 95% 57Fe. We did not find any evidence of species conversion of the isotopic label for at least 5 months of storage at −20 °C. Transfer efficiency of enriched iron into [57Fe]ferritin of 20% was sufficient to be economically feasible. Negligible amounts of non-ferritin-bound iron in the purified [57Fe]ferritin solution allows for use of this spike for quantification of ferritin-bound iron by isotope dilution mass spectrometry.  相似文献   

5.
This work assessed the phenolic and flavonoid components and their antioxidant, antifungal, and antibacterial effects in the ethanolic extract of barberry leaf and roots. The antibactericidal activity of root and leaf extracts against pathogenic bacteria was tested using agar diffusion and microdilution broth production for the lowest inhibitory concentration (MIC). Berberis vulgaris root and leaf extracts inhibited Staphylococcus aureus ATCC9973, Escherichia coli HB101, Staphylococcus enteritis, and Escherichia coli Cip812. The disc assay technique was used to assess the bactericidal activity of the extracts versus both pathogenic Gram-positive and Gram-negative strains. Hydro alcoholic extract was more effective against bacterial than fungal strains. The results showed that Berberis vulgaris leaf and roots extract had similar antifungal activities. Berberis vulgaris root extract inhibited the mycelial growth of Penicillium verrucosum, Fusarium proliferatum, Aspergillus ochraceous, Aspergillus niger, and Aspergillus flavus. Berberis vulgaris root extract has excellent antioxidant, antibacterial, and antifungal effects. Berberis vulgaris exhibited antimicrobial activity in vitro, and MIC showed that Berberis vulgaris parts efficiently affected pathogens in vitro. In conclusion, both Berberis vulgaris roots and leaves have considerable antibacterial activity and can be used as a source of antibacterial, antioxidant, and bioactive compounds to benefit human health.  相似文献   

6.
Palmatine (PLT) is a natural isoquinoline alkaloid that belongs to the class of protoberberines and exhibits a wide spectrum of pharmacological and biological properties, including anti-cancer activity. The aim of our study was to isolate PLT from the roots of Berberis cretica and investigate its cytotoxic and anti-proliferative effects in vitro alone and in combination with doxorubicine (DOX) using human ER+/HER2 breast cancer cell lines. The alkaloid was purified by column chromatography filled with silica gel NP and Sephadex LH-20 resin developed in the mixture of methanol: water (50:50 v/v) that provided high-purity alkaloid for bioactivity studies. The purity of the alkaloid was confirmed by high resolution mass measurement and MS/MS fragmentation analysis in the HPLC-ESI-QTOF-MS/MS-based analysis. It was found that PLT treatment inhibited the viability and proliferation of breast cancer cells in a dose-dependent manner as demonstrated by MTT and BrdU assays. PLT showed a quite similar growth inhibition on breast cancer cells with IC50 values ranging from 5.126 to 5.805 µg/mL. In contrast, growth of normal human breast epithelial cells was not affected by PLT. The growth inhibitory activity of PLT was related to the induction of apoptosis, as determined by Annexin V/PI staining. Moreover, PLT sensitized breast cancer cells to DOX. Isobolographic analysis revealed synergistic and additive interactions between studied agents. Our studies suggest that PLT can be a potential candidate agent for preventing and treating breast cancer.  相似文献   

7.
Summary Chromatographic methods for the qualitative and quantitative analysis of thyme (Thymus vulgaris L.) extracts (essential oil obtained by steam distillation and extracts obtained by carbon dioxide supercritical fluid extraction and methylene chloride) are described. The composition of extracts obtained at different pressures (from 80 bar to 400 bar) and constant temperature (40°C) is discussed. The extraction system thyme— supercritical carbon dioxide was modelled by empirical equations defining the dependence of the total extract (TE) solubility and thymol solubility in CO2 on the density of carbon dioxide.  相似文献   

8.
Twelve acidic triterpene glycosides of oleanolic acid, two of which were new, were isolated from stem bark of Tetrapanax papyriferum C. Koch (Araliaceae). The structures of these compounds were established using chemical methods and NMR spectroscopy.  相似文献   

9.
The polarographic behaviour of the title compound in buffer solution ofpH 2–21 is discussed. The two observed waves in alkaline media (pH9.5) are assigned to the formation of hydrazo and the bishydrazo derivatives, whereas in acid solutions the reduction leads to cleavage of both two azo groups. The nature of the waves is investigated and a general mechanism for the reduction process in alkaline and acid media is suggested. The values of the kinetic parameters for the electrode reactions are reported.
Untersuchungen an Bisazo-Verbindungen I. Polarographisches Verhalten von 1-[4-(4-Natriumsulfonato-phenylazo)-3-natriumsulfonato-phenylazo]-2-naphthol in Lösungen mit verschiedenem pH an der tropfenden Quecksilber-Elektrode Polarographic behaviour of 1-[4-(4-sodiumsulfonato-phenylazo)-3-sodiumsulfonato-phenylazo]-2-naphthol in solutions of varyingpH at the dropping mercury electrode
Zusammenfassung Es wird das polarographische Verhalten der Titelverbindung in Pufferlösungen vompH 2–12 diskutiert. Die zwei im alkalischen Bereich (pH9,5) beobachteten Wellen werden der Bildung der Hydrazo- bzw. Bishydrazo-Derivate zugeordnet, im sauren Bereich führt die Reduktion zur Spaltung beider Azo-Gruppen. Die Natur der Wellen wird untersucht, und ein genereller Mechanismus für die Reduktion im alkalischen und sauren Bereich wird vorgeschlagen. Die kinetischen Parameter der Elektrodenreaktionen werden angegeben.
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10.
引入跨股氨基酸队的方法进行β-发夹结构的设计,序列[R1G2T3F4W5V6d-P7S8V9N10Y11F12, β2] 中包含二个氨基酸对V6V9和F4Y11,并以d-P7S8作转角来稳定结构.多肽合成采用Fmoc/But固相合成方法.圆二色谱研究显示,β2在202 nm呈现正峰,在217.5 nm处呈负峰,为β转角和β折叠共同贡献的叠加,是典型的β-发夹结构圆二色谱特征.红外光谱研究进一步验证了圆二色谱的结果,表明β2在溶液中主要以β-发夹结构存在.  相似文献   

11.
Thirteen known glycosides of hederagenin and oleanolic acid and the three new triterpene glycosides of oleanolic acid-28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl ester 3-O-β-D-glucopyranosyl-(1→4)-O-β-D-xylopyranosyl-(1→ 3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and the 28-O-α-L-rhamnopyranosyl-(1→4)-O-6-O-acetyl-β-D-glucopyranosyl-(1→ 6)-O-β-D-glucopyranosyl esters 3-O-β-D-xylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranoside of oleanolic acid and 3-O-β-D-glucopyranosyl-(1→4)-O-β-Dxylopyranosyl-(1→3)-O-α-L-rhamnopyranosyl-(1→ 2)-O-α-L-arabinopyranoside of oleanolic acid were isolated from leaves of Kalopanax septemlobum var. typicum introduced to Crimea. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–43, January–February, 2006.  相似文献   

12.
Soluble products obtained from the oxidation of four types of coal, each characterised by different degree of coalification and different degree of sulphur content, are studied. The coals are oxidised with peracetic acid (PAA) and nitric acid. Analyses are performed by Atmospheric Pressure-Temperature Programmed Reduction (AP-TPR) and Fourier Transform Infrared Spectroscopy (FTIR). The soluble products contain much more sulphur than the insoluble products of oxidation. The products obtained from the reaction with HNO3 contain higher amounts of inorganic sulphur compounds, while those obtained from the reaction with PAA are characterised by an increased content of organic sulphur species.  相似文献   

13.
The preparation and properties of the crystalline compounds of the type NiL 4Cl2, NiL 2Cl2 and NiLCl2 (L=N-aryl thioureas) are described. Analytical, conductometric, magnetic and spectral data (infrared and electronic)_show that complexes of the type NiL 4Cl2 possess octahedral structure and those of NiL 2Cl2 and NiLCl2 are characterised as distorted octahedral in solid state. The ligand field parametersD q ,B and calculated from electronic spectral data, suggest a weak field for all the ligands. Metal sulphur bonding for all ligands is adduced from infrared and far infrared spectral studies.
Untersuchungen an Nickel(II) Komplexen von N-Aryl-thioharnstoff Derivaten
Zusammenfassung Darstellung und Eigenschaften der kristallinen Verbindungen vom Typ NiL 4Cl2, NiL 2Cl2 und NiLCl2 (L=N-Arylthioharnstoff) werden beschrieben. Magnetische Eigenschaften, Leitfähigkeitsmessungen, analytische und spektroskopische Daten beweisen, daß die Komplexe vom Typ NiL 4Cl2 oktaedrische Struktur besitzen; die Komplexe vom Typ NiL 2Cl2 und NiLCL2 weisen eine verzerrt oktaedrische Geometrie auf. Die Ligandenfeld-ParameterD q ,B und , die aus Elektronenanregungsspektren berechnet wurden, zeigen ein schwaches Feld für alle untersuchten Liganden an Aus Untersuchungen der Spektren des IR und fernen IR folgt, daß die Komplexe eine Metall—Schwefel-Bindung aufweisen.
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14.
The new natural compound lavandoside with the structure ferulic acid 4-O-β-D-glucopyranoside was isolated by column chromatography over silica gel and polyamide from the extract of Lavandula spica flowers. The chemical structure of lavandoside was established using UV, NMR, and mass spectra and chemical transformations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 133–134, March–April, 2008.  相似文献   

15.
The qualitative and quantitative compositions of the main groups of biologically active substances from roots of several Kazakhstan Rumex species were compared. The amino-acid compositions of all species were studied for the first time.  相似文献   

16.
Transformation of β-carboline derivatives into optically active entities were studied and the de and ee values of the resulted compounds were detected. Dedicated to Professor Károly Lempert on his 80th birthday.  相似文献   

17.
以齐墩果酸为原料,简洁地合成得到齐墩果烷型二烯酮化合物7.采用不同氧化剂对化合物7进行了氧化研究,发现H2O2/HCOOH可以立体专一性地氧化断裂二烯酮,高产率地得到单一构型的齐墩果酸AB和DE环十氢萘手性合成子.所得产物及中间体经红外、质谱、1H NMR和13C NMR进行表征.  相似文献   

18.
麝香草的新单萜配糖物的分离与合成   总被引:1,自引:0,他引:1  
从麝香草(Thymus vulgaris L)的甲醇萃取物中分离出三个单萜配糖物. 用核磁共振光谱确定了它们的结构为对伞花-9-基-β-D-葡糖苷(1), 5-β-D-葡糖苷百里氢醌(2)和2-β-D-葡糖苷百里氢醌(3). 其中1是新化合物, 用以对伞花-9-醇为原料的对映体选择性合成方法确定了化合物1的8位的立体化学为R型.  相似文献   

19.
Sixteen triterpene glycosides, three of which were new, hederagenin 28-O-β-D-glucuronopyranosyl ester and 28-O-β-D-gentiobiosyl ester and oleanolic acid 3-O-α-L-arabinopyranoside, were isolated from stem bark of Kalopanax septemlobum. The glycoside contents in stem bark of two varieties, maximowiczii and typicum, were compared. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 49–53, January–February, 2006.  相似文献   

20.
The formation of copper(II) complexes with N,N-diethylglycine in acetonitrile has been investigated by visible, infrared as well as NMR spectral techniques. It has been found that 11 and 12 complexes are formed. In both compounds nitrogen and carboxyl oxygen of ligand molecules are involved in coordination. The stability constants are reported.
Untersuchungen von Kupfer(II)-Komplexen mit N,N-Diethylglycin in Acetonitril
Zusammenfassung Die Bildung von Kupfer(II)-Komplexen mit N,N-Diethyglycin in Acetonitril wurde mit Hilfe von UV-VIS, IR- und NMR-Spektroskopie untersucht. Es wurde festgestellt, daß sich Komplexe der Zusammensetzung 11 und 12 bilden. In beiden Verbindungen koordinieren Stickstoff und Carboxylsauerstoff der Liganden. Die Stabilitätskonstanten wurden bestimmt.
  相似文献   

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