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81.
中草药中槲皮素的毛细管电泳法测定   总被引:7,自引:0,他引:7  
近年来,毛细管电泳法用于中药的分析正在逐渐展开.微波辅助萃取是微波与传统的溶剂萃取法相结合后形成的一种新的萃取方法,目前已被用于环境、食品和天然产物的提取等领域,我们也曾用微波萃取法研究了中药刺五加和黄芩中的黄酮类化合物。  相似文献   
82.
研究了硝酸介质中痕量硒(Ⅳ)催化溴酸钾氧化罗丹明B的褪色反应及动力学条件, 建立了动力学光度法测定痕量硒(Ⅳ)的新方法, 其灵敏度为0.905 μg·L-1, 测定范围0~9.6 μg·L-1。用于测定抗癌中草药中的硒(Ⅳ), 获得了满意的结果。  相似文献   
83.
Epimedin C, an ingredient of Herba Epimedii, has potential for treatment of cardiovascular disease and bone loss. However, there is still no sensitive analytical method to monitor epimedin C in biological samples. The goal of this study was to develop a sensitive and reliable method based on a LC‐MS/MS for evaluating the pharmacokinetics of epimedin C after administration of Herba Epimedii in rat. Electrospray ionization in positive‐ion mode and multiple reaction monitoring were used to identify and quantitate active components. Analytes were separated by a reverse‐phase C18 column. Liquid–liquid extraction using ethyl acetate, evaporation and reconstitution was used to plasma sample preparation. Mass transition of precursor ion → product ion pairs were monitored at m/z 823.4 → 313.1 for epimedin C and m/z 237.1 → 178.9 for carbamazepine (internal standard). A calibration curve gave good linearity (r > 0.999) over the concentration range 2.5–500 ng/mL. Pharmacokinetic data demonstrated that there was rapid distribution and slow elimination after epimedin C administration (1 mg/kg, i.v.). Oral bioavailabilities of epimedin C in the pure compound and in the Herba Epimedii were around 0.58% and 0.13%, respectively. The result suggests that other herbal ingredients of Herba Epimedii may suppress the oral bioavailability of epimedin C. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
84.
The electrochemical behavior of anticancer herbal drug berberine was investigated in 0.2 mol L‐1 HAc‐NaAc (pH 4.2) buffer solution at a glassy carbon electrode. The drug yields a single well‐defined reduction peak at the potential of ‐1.085 V at the scan rate of 0.05 V s‐1 and the electrode reaction is an irreversible adsorption‐controlled process as the result of cyclic voltammetry. All experimental conditions were studied in order to obtain the optimum conditions for the determination of berberine. A good linear relationship was observed between the reductive peak currents and the concentrations of berberine in the range from 1.0 × 10‐6 to 8.0 × 10‐5 mol L‐1. The detection limit of 8.0 × 10‐7 mol L‐1 was obtained in terms of the signal to noise ratio of 3:1 (S/N = 3). The proposed technique was applied to determine the content of berberine in tablets with good satisfactory. In addition, the electrode process dynamics parameters were calculated.  相似文献   
85.
Chemical fingerprinting methodology is an approach for quality assessment and control of herbal medicines and related products based on the holistic chemical profile obtained by various analytical techniques. This study demonstrates the first application of paper spray mass spectrometry (PS-MS) as a chemical fingerprinting methodology for tracing the origins, establishing the authenticity, and assessing the overall quality of a famous herbal product, Bansha herbal tea (BHT). A negative ion PS-MS spectrum yielded the best chemical profiling information and was most appropriate for fingerprint analysis of BHT. In addition to the identification of active ingredients, various compounds present in BHT were simultaneously detected without any sample pretreatment and chromatographic separation, providing valuable information for the quality assessment and control of this herbal product. According to the principal component analysis of the PS-MS fingerprints, two sources of commercially available BHT products made by different manufacturers were easily differentiated. Qualified and expired products from the two manufacturers were also successfully distinguished, and the consistency of the quality between the manufacturers was assessed. Our experimental data demonstrated that the PS-MS chemical fingerprinting is a simple, rapid, and robust methodology for pharmaceutical analysis, with promising prospects for quality assessment and control of herbal medicines and related products with high-throughput.  相似文献   
86.
石墨炉原子吸收光谱法分析药用植物中微量营养元素的含量   总被引:30,自引:4,他引:26  
银杏、杜仲及绞股蓝的成熟青叶晾干并粉碎后经HNO3-HClO4(4:1)混酸消化,用石墨炉原子吸收法同时分析测定了消化液中的Se,Ge,Cu,Zn,Fe,Mn六种微量元素,方法简便快速。用该方法测定了桃叶标准物中的Cu,Zn,Fe,Mn四种微量元素,证明了测定结果准确可靠。实验结果表明这三种药用植物叶中Cu,Zn,Fe,Mn含量都较为丰富,特别是银杏叶中的Se,绞股蓝中的Ge含量较高,对微量元素与中草药药效的关系进行了初步探讨。  相似文献   
87.
The herbal stimulants Ephedra species, Catha edulis (khat), and Lophophora williamsii (peyote) have been abused for a long time. In recent years, the herbal drug market has grown owing to publicity on the Internet. Some ingredients of these plants are also ingredients of cold remedies. The aim of the presented study is to develop a multianalyte procedure for detection and validated quantification of the phenalkylamines ephedrine, pseudoephedrine, norephedrine, norpseudoephedrine, methylephedrine, methylpseudoephedrine, cathinone, mescaline, synephrine (oxedrine), and methcathinone in plasma. After mixed-mode solid-phase extraction of 1 ml of plasma, the analytes were separated using a strong cation exchange separation column and gradient elution. They were detected using a Q-Trap LC-ESI-MS/MS system (MRM mode). Calibration curves were used for quantification using norephedrine-d3, ephedrine-d3, and mescaline-d9 as internal standards. The method was validated according to international guidelines. The assay was selective for the tested compounds. It was linear from 10 to 1000 ng/ml for all analytes. The recoveries were generally higher than 70%. Accuracy ranged from - 0.8 to 20.0%, repeatability from 2.5 to 12.3%, and intermediate precision from 4.6 to 20.0%. The lower limit of quantification was 10 ng/ml for all analytes. No instability was observed after repeated freezing and thawing or in processed samples. The applicability of the assay was tested by analysis of authentic plasma samples after ingestion of different cold medications containing ephedrine or pseudoephedrine, and after ingestion of an aqueous extract of Herba Ephedra. After ingestion of the cold medications, only the corresponding single alkaloids were detected in human plasma, whereas after ingestion of the herb extract, all six ephedrines contained in the plant were detected. The presented LC-MS/MS assay was found applicable for sensitive detection and accurate and precise quantification of all studied analytes in plasma.  相似文献   
88.
Gums are carbohydrate biomolecules that have the potential to bind water and form gels. Gums are regularly linked with proteins and minerals in their construction. Gums have several forms, such as mucilage gums, seed gums, exudate gums, etc. Plant gums are one of the most important gums because of their bioavailability. Plant-derived gums have been used by humans since ancient times for numerous applications. The main features that make them appropriate for use in different applications are high stabilization, viscosity, adhesive property, emulsification action, and surface-active activity. In many pharmaceutical formulations, plant-based gums and mucilages are the key ingredients due to their bioavailability, widespread accessibility, non-toxicity, and reasonable prices. These compete with many polymeric materials for use as different pharmaceuticals in today’s time and have created a significant achievement from being an excipient to innovative drug carriers. In particular, scientists and pharmacy industries around the world have been drawn to uncover the secret potential of plant-based gums and mucilages through a deeper understanding of their physicochemical characteristics and the development of safety profile information. This innovative unique class of drug products, useful in advanced drug delivery applications, gene therapy, and biosynthesis, has been developed by modification of plant-based gums and mucilages. In this review, both fundamental and novel medicinal aspects of plant-based gums and mucilages, along with their capacity for pharmacology and nanomedicine, were demonstrated.  相似文献   
89.
A novel strategy based on the use of bionic membrane camouflaged magnetic particles and LC–MS was developed to quickly screen the biomembrane-permeable compounds in herbal medicines. The bionic membrane was constructed by bubble-generating magnetic liposomes loaded with NH4HCO3 (BMLs). The lipid bilayer structure of the liposomes enabled BMLs to capture biomembrane-permeable compounds from a herbal extract. The BMLs carrying the compounds were then separated from the extract by a magnetic field. Upon heat treatment, NH4HCO3 rapidly decomposed to form CO2 bubbles within the liposomal bilayer, and the captured compounds were released from BMLs and analyzed by LC–MS. Jinlingzi San (JLZS), which contains various natural ingredients, was chosen to assess the feasibility of the proposed method. As a result, nine potential permeable compounds captured by BMLs were identified for the first time. Moreover, an in vivo animal study found that most of the compounds screened out by the proposed method were absorbed into the blood. The study provides a powerful tool for rapid and simultaneous prediction of multiple biomembrane-permeable components.  相似文献   
90.
Depression and anxiety are major mental health problems in all parts of the world. These illnesses are associated with a number of risk factors, including oxidative stress. Psychotropic drugs of a chemical nature have demonstrated several side effects that elevated the impact of those illnesses. Faced with this situation, natural products appear to be a promising alternative. The aim of this study was to evaluate the anxiolytic and antidepressant effects of the Petroselinum sativum polyphenols in vivo, as well as its correlated antioxidant properties in vitro. Anxiolytic activity of the extract (50 and 100 mg/kg) was evaluated using the open field and the light-dark chamber tests, while the antidepressant activity was evaluated using the forced swimming test. The antioxidant activity of the extract was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical test and the FRAP (iron-reducing capacity) test. The phenolic extract showed very powerful anxiolytic and antidepressant-like effects, especially at a dose of 100 mg/kg, decreasing the depressive behavior in mice (decreased immobility time) and also the anxiolytic behavior (tendency for discovery in the center and illuminated areas) better even than those of paroxetine and bromazepam (classic drugs) concomitant with those results the extract also showed an important antioxidant capacity. These preliminary results suggest that Petroselinum sativum exhibits anxiolytic and antidepressant potential for use as a complement or independent phytomedicine to treat depression and anxiety.  相似文献   
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