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An HPLC method is described for determination of ferulic acid in rat plasma. The concentration of ferulic acid in rat plasma was determined after deproteinization with acetonitrile using sulfamethoxazole as internal standard. Chromatographic separations were performed on a C(18) stationary phase with a mobile phase composed of acetonitrile-water (16:84, v/v) with 1% glacial acetic acid. The UV detection wavelength was set at 320 nm. The method was successfully applied to the determination of pharmacokinetic parameters in rat plasma after oral administration of Rhizoma Chuanxiong and and its compound preparation Suanzaoren decoctions. The calibration curve was linear over the range 0.0510-4.08 micro g/mL in rat plasma. Within-day and between-day precisions were less than 4.5% RSD. Mean recovery was determined as 96.9%. The limit of quantitation was 0.0510 micro g/mL. The pharmacokinetic parameters of the two preparations were different significantly (p < 0.05), which may attribute to the effects of other ingredients present in Suanzaoren decoction.  相似文献   
3.
四君子汤和四物汤微量元素含量研究   总被引:1,自引:0,他引:1  
通过了解中药“四君子汤”和“四物汤”中微量元素含量的异同,研讨了微量元素和中医“气血”理论之间的关系。实验表明,“四君子汤”和“四物汤”在微量元素的含量方面,有一定的类同和差异。该现象同中医的“气血”理论有非常相像的地方。同时发现中药中的微量元素在煎煮过程中,并不是同想象的一样匀速进入药液,而是不同的元素在不同的时间段不同的批次进入药液,这也提示中药煎法理论有一定依据。由于目前做的实验还少,本实验留下很多问题和疑点,值得进一步做有关的实验和研究。  相似文献   
4.
A multidisciplinary investigation on Achillea moschata Wulfen (Asteraceae) is outlined herein. This work, part of the European Interreg Italy–Switzerland B-ICE project, originated from an ethnobotanical survey performed in Chiesa in Valmalenco (Sondrio, Lombardy, Northern Italy) in 2019–2021 which highlighted this species’ relevance of use in folk medicine to treat gastrointestinal diseases. In addition, this contribution included analyses of the: (a) phytochemical profile of the aqueous and methanolic extracts of the dried flower heads using LC-MS/MS; (b) morpho-anatomy and histochemistry of the vegetative and reproductive organs through Light, Fluorescence, and Scanning Electron Microscopy; (c) biological activity of the aqueous extract concerning the antioxidant and anti-inflammatory potential through cell-based in vitro models. A total of 31 compounds (5 phenolic acids, 13 flavonols, and 13 flavones) were detected, 28 of which included in both extracts. Covering and secreting trichomes were observed: the biseriate 10-celled glandular trichomes prevailing on the inflorescences represented the main sites of synthesis of the polyphenols and flavonoids detected in the extracts, along with volatile terpenoids. Finally, significant antioxidant and anti-inflammatory activities of the aqueous extract were documented, even at very low concentrations; for the first time, the in vitro tests allowed us to formulate hypotheses about the mechanism of action. This work brings an element of novelty due to the faithful reproduction of the traditional aqueous preparation and the combination of phytochemical and micromorphological research approaches.  相似文献   
5.
白术煎剂表面增强拉曼光谱分析   总被引:4,自引:0,他引:4  
测试分析了白术煎剂及其在银胶中的拉曼光谱,并对其进行初步谱峰归属。白术煎剂表面增强拉曼光谱在396,548,617,730,955和1 327 cm-1处,出现6个明显的拉曼信号。测试了白术煎剂和白术煎剂-银胶混合体系的紫外-可见吸收光谱,该吸收光谱在长波区出现新共振吸收峰(999 nm处),进而研究了白术煎剂在银溶胶上的吸附特性及其表面增强机理。结果表明,表面增强拉曼光谱可能为白术煎剂或其他中药煎剂提供一种准确、直接、快速的检测方法。  相似文献   
6.
Danshen (DS) is a widely used traditional Chinese medicine for treating cardiovascular and cerebrovascular diseases. A simple, rapid and sensitive method was developed for identification of the in vivo metabolites in urine of WZS‐miniature pigs after oral administration of DS decoction by HPLC coupled with diode array detection with electrospray ionization tandem ion trap and time‐of‐flight mass spectrometry. This method has been successfully applied to simultaneous identification of 50 compounds (including 11 new ones) in pig urine. In addition, one new compound, (3‐hydroxyphenyl) crylic acid glycine methyl ester (C1), along with eight known ones were first isolated by column chromatography and identified by spectroscopic means, including 1D/2DNMR and mass spectrometry, as reference substances. Ten phenolic compounds (protocatechuic aldehyde, protocatechuic acid, caffeic acid, danshensu, ferulic acid, isoferulic acid, rosmarinic acid and salvianolic acid A/B/D) were found to be the main absorbed original constituents of DS decoction, which underwent the metabolic reactions of glucuronidation, sulfation, methylation, hydrogenation and glycine conjugation in vivo. In conclusion, the developed method is applicable to the analysis and identification of constituents in biological matrices after administration of DS decoction. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
7.
A highly selective and efficient LC–MS/MS method was developed to determine the plasma concentration of magnolol, hesperidin, neohesperidin and geniposide following oral administration of Zhi‐Zi‐Hou‐Po decoction in normal and depressed rats. Plasma samples were pretreated by protein precipitation with methanol. Chromatographic separation was performed on an XTerra® MS C18 column using a gradient elution with a mobile phase composed of acetonitrile–0.1% aqueous formic acid. The proposed method was validated to be specific, accurate and precise for the analytes determination in plasma samples. The calibration curves displayed good linearity over definite concentration ranges for the analytes. The intra‐ and inter‐day precision of the proposed method at three different levels were all within <11.13% and the relative errors ranged from ?8.46 to 8.93%. The recovery of the four compounds ranged from 82.72 to 89.08% and no apparent matrix effect was observed during sample analysis. After full validation, the established method was successfully applied for comparing the pharmacokinetics of four components between normal and depressed rats. The results showed that the AUC and Cmax of four analytes in depressed rats were significantly different from those in normal rats and might provide helpful information to guide the clinical use of Zhi‐Zi‐Hou‐Po to treat depression.  相似文献   
8.
Monoester‐diterpenoid alkaloids are the main bioactive components of Sini decoction, which is a well‐known traditional Chinese medicine formula for the treatment of myocardial infarction (MI) and heart failure in China. In this work, an ultra‐high‐performance liquid chromatography–mass spectrometry combined with microdialysis method was successfully established and applied for investigating for the first time comparative plasma pharmacokinetics of three monoester‐diterpenoid alkaloids (benzoylmesaconitine, benzoylaconitine and benzoylhypacoitine) in normal and MI rats after oral administration of Sini decoction. The statistical results of pharmacokinetic parameters demonstrated that benzoylmesaconitine, benzoylaconitine and benzoylhypacoitine showed lower peak concentration, longer half‐life, smaller area under the concentration–time curve, slower clearance, time to peak concentration and mean residence time in MI rats than in normal rats (p < 0.05), which indicated that monoester‐diterpenoid alkaloids exhibited lower systemic exposure and slower elimination in the MI rats. The results provided the experimental basis for understanding the metabolic fate and therapeutic effects of Sini decoction.  相似文献   
9.
Salvia miltiorrhiza, one of the most well‐known herbal medicines, is commonly used for the treatment of coronary heart diseases in China. Besides traditional decoction slices (TDS), another relatively new product of S. miltiorrhiza, ultrafine granular powder (UGP; D90 < 45 μm), is also increasingly being used. In this paper, a UHPLC‐LTQ‐Orbitrap MS technique was developed for a metabolite profile study after oral administration of UGP and TDS of S. miltiorrhiza. The results showed that the number of in vivo absorbed compounds from UGP was much greater than that from TDS, and different types of products from S. miltiorrhiza will have different metabolic processes in vivo. Furthermore, a UHPLC‐Q‐Trap MS/MS method for simultaneously determining four tanshinones (tanshinone IIA, dihydrotanshinone I, tanshinone I and cryptotanshinone) was established and applied to assess the pharmacokinetics of the two types of products. All of the analytes displayed significant higher area under the concentration–time curve and peak concentration after oral administration of UGP than after TDS, indicating that ultrafine powder product could improve the bioavailability and absorption of cryptotanshinon,tanshinone II A,dihydrotanshinonE I and tanshinone I in vivo. The present study provides scientific information for further exploration of the pharmacology of these two types of S. miltiorrhiza and offers a reference for clinical administration of S. miltiorrhiza.  相似文献   
10.
模拟传统煎药方式,制备巴戟天水煎液。用电感耦合等离子体质谱法(ICP-MS)测定了药材及其水煎液中11种微量元素Cr、Mn、Co、Ni、Cu、Zn、As、Se、Cd、Sn、Pb含量,用火焰原子吸收光谱法(FAAS)测定了微量元素Fe含量。根据微量元素含量,得到了药材及水煎液微量元素的分布模式。结果表明,巴戟天药材样品富含人体必需元素Fe、Mn、Zn,含量分别是1086.3、393.8、15.1μg.g-1;巴戟天药材与水煎液微量元素的分布模式图清晰地显示了其微量元素的分布特征,且药材与水煎液微量元素的分布模式以及不同煎制时间下水煎液微量元素的分布模式均存在明显差异,进而表明这种微量元素分布模式对中药微量元素的研究和临床应用具有参考价值。  相似文献   
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