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1.
用毛细管电泳法,对黄连与黄柏配伍后共煎剂中的主要生物碱进行了分析。以50 mmol/L Na2B4O7(pH=7)-CH3OH(85:15,V/V)为背景电解质,操作电压为14 kV,电迁移进样10 kV×5s,柱上223 nm检测,5种主要生物碱9 min内可在50 cm×75μm毛细管上实现基线分离。以小檗碱、巴马汀的提取量为指标,分析了提取剂对提取效果的影响。以30%的乙醇水溶液为提取剂,可得到最大煎出量。  相似文献   
2.
微波-同时蒸馏萃取分离肉桂挥发性成分分析   总被引:5,自引:0,他引:5  
经粉碎的肉桂干燥树皮置于去离子水中微波加热处理后,用自制的同时蒸馏-萃取装置,以重蒸乙醚为溶剂将试样中的挥发组分萃取分离。用旋转蒸发器除去乙醚后即得到含有试样中挥发组分的透明的黄色液体,收得率为6.5%,应用GC/MS法对黄色液体的组分进行定性和定量分析。借助于联机的计算机和相关软件并用峰面积-归一化计算测得其中共有27个化合物,其中含量最高的是肉桂醛,达94.36%。另取部分上述挥发油(即黄色液体),用加成分解法将其中肉桂醛转化为一种加成产物以沉淀形式析出,即将黄色液体与NaHSO3共置于微波炉中,在不超过10℃的条件下处理直至加成物完全析出。将此加成物分出,并用0.1 mol.L-1盐酸进行水解处理,使加成物恢复成纯度较高的肉桂醛,用IR及MS对其组成及结构作进一步确认。  相似文献   
3.
Root cortex of Paeonia suffruticosa Andrews (Paeoniaceae), known as Moutan Cortex (MC), is known to have anti‐allergic and anti‐inflammatory properties. However, the constituents absorbed into blood after oral administration of MC remain unknown. A sensitive and rapid method by ultra‐high‐pressure liquid chromatography–electrospray ionization–quadrupole‐time‐of‐flight mass spectrometry (UPLC‐ESI‐Q‐TOF‐MS) technology and the MetaboLynxTM software combined with multiple data processing approach (Mdpa) was established to investigate the absorbed constituents in rats after oral administration of MC, providing unique high‐throughput capabilities for drug metabolism study. A hyphenated electrospray ionization and quadrupole‐time‐of‐flight analyzer was used for the determination of accurate mass of the fragment ion in negative mode, with excellent MS mass accuracy and enhanced data acquisition. This rapid automated analysis method was successfully applied for screening and identification of the constituents absorbed and metabolized studies of MC after oral administration to rats. A total of 46 peaks were obtained from MC, 41 of which were tentatively characterized. In the VIP‐plot of orthogonal partial least‐squares discriminant analysis, 23 interesting ions in serum samples were extracted, and 16 parent components and seven metabolites were detected in vivo. The integrative serum pharmacochemistry technique, UPLC‐ESI‐Q‐TOF‐MS, and Mdpa method were successfully applied for rapid discovery of multiple components from MC. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
4.
Ultra performance LC with quadrupole TOF MS (UPLC/Q‐TOF‐MS) fingerprinting is first developed for the identification of the major components of Phellodendri Amurensis Cortex (PAC). The PAC samples are separated using a Waters ACQUITY UPLC BEH C18 (2.1×50 mm, 1.7 μm) by linear gradient elution using water (containing 0.2% formic acid) and acetonitrile (containing 0.2% formic acid) as the mobile phase. Ten batches of PAC are selected to construct the UPLC/Q‐TOF‐MS fingerprint. Sixteen common peaks in the fingerprint are obtained, ten of which are tentatively identified, with reference to the literature data, as phellodendrine, magnoflorine, tetrahydropjatrorrhizine, menisperine, tetrahydropalmatine, jatrorrhizine, palmatine, berberine, obacunone, and limonin. Chemometric methods are also employed to evaluate the variation of herbal drugs and other closely related herbs based on the characteristics of peaks in the UPLC/Q‐TOF‐MS profiles. The developed fingerprint assay is a powerful method that may be used to conduct quality control of PAC.  相似文献   
5.
A simple method based on liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry (LC‐DAD‐ESI‐MS) was developed for the quality assessment of Cortex Phellodendri (CP), which was mainly derived from two species of Phellodendron chinense Schneid and Phellodendron amurense Rupr. Total 41 compounds, including 14 phenols, 24 alkaloids and three liminoidal triterpenes were identified or tentatively characterized from the 75% methanol extract of CP samples by online ESI‐MSn fragmentation and UV spectra analysis. Among them, two phenols and six alkaloids were simultaneously quantified using HPLC‐DAD method. The validated HPLC‐DAD method showed a good linearity, precision, repeatability and accuracy for the quantification of eight marker compounds. Furthermore, the plausible fragmentation pathway of the representative compounds were proposed in the present study. The differences of the chemical constituents content and the comprehensive HPLC profiles between the two CP species using LC‐DAD‐ESI‐MS method are reported for the first time, indicating that the CP drugs from different resources should be used separately in the clinic. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
6.
Juglandis Mandshuricae Cortex is the bark of Juglans mandshurica Maxim., which has been used as a folk medicine plant in China and India. In this study, an ultra-high performance liquid chromatography–quadrupole/orbitrap high-resolution mass spectrometry method was developed to clarify and quantify the chemical profiling of Juglandis Mandshuricae Cortex rapidly. A total of 113 compounds were characterized. Among them, seven flavonoids were simultaneously quantified in 15 min, including myricetin, myricetrin, taxifolin, kaempferol, quercetin, quercitrin, and naringenin. The method was validated for accuracy, precision, and the limits of detection and quantification. All calibration curves showed a good linear relationship (r > 0.9990) within test ranges. The intra- and inter-day relative standard deviations were less than 2.16%. Accuracy validation showed that the recovery was between 95.6 and 101.3% with relative standard deviation values below 2.85%. The validated method was successfully applied to determine the contents of seven flavones in Juglandis Mandshuricae Cortex from seven sources and the contents of these places were calculated respectively. This method provides a theoretical basis for further developing the medicinal value of Juglandis Mandshuricae Cortex.  相似文献   
7.
Eucommiae Cortex is a classical traditional Chinese medicine, which needs to be processed by “sweating” methods. To select the suitable processing method and “sweating” processing condition for Eucommiae Cortex, in this study, the quality of Eucommiae Cortex was evaluated based on simultaneous determination of multiple bioactive constituents combined with gray relational analysis. The contents of lignans, iridoids, penylpropanoids, flavonoids, and phenols in samples were simultaneously determined using ultra‐fast performance liquid chromatography coupled with triple quadrupole‐linear ion trap tandem mass spectrometry. The chromatographic separation was performed on a Synergiۛ Hydro‐RP 100 Å column (100 mm × 2.0 mm, 2.5 μm) at 30°C with a gradient elution of acetonitrile with 0.1% formic acid/0.1% aqueous formic acid as the mobile phase. Furthermore, gray relational analysis was performed to evaluate and sort the samples according to the contents of 14 constituents by calculating the relative correlation degree of each sample. The results demonstrated that the quality of Eucommiae Cortex “sweating” at source area was better and the better “sweating” condition was to scrape off the cork layer before “sweating” with straw covering and sun drying. The developed method could provide the foundation and support for “sweating” processing method of Eucommiae Cortex in normalization and standardization.  相似文献   
8.
In this study, a rapid and reliable assay has been developed for quantification of pinane monoterpene glycosides in cortex Moutan; it is based on capillary high performance liquid chromatography coupled with electrospray ionization mass spectrometry (capillary HPLC-ESI MS). This method utilizes capillary HPLC for the separation of seven pinane monoterpene glycosides in a methanol extract of the botanical sample followed by negative ion electrospray ionization and single ion monitoring (SIM). The compounds of interest in the sample were unambiguously identified on the basis of information about retention time and quasi-molecular ions ([M-H](-)) or adduct ions ([M+HCOO](-)). Validation parameters of the method were established. The linearity range was 1.01-105.5 microg/mL with the square of correlation coefficients lying in the range of 0.9965-0.9997, limits of detection were on the fmol level, the average recoveries varied between 91.8 and 101.0%, and good precision values (RSD, 1.2-4.91%) for peak area were obtained. After validation, the applicability of the method for determination of these pinane monoterpene glycosides in cortex Moutan has been demonstrated.  相似文献   
9.
This paper developed a rapid method using near infrared spectroscopy (NIRS) to differentiate two species of Cortex Phellodendri (CP), Cortex Phellodendri Chinensis (PCS) and Cortex Phellodendri Amurensis (PAR), and to predict quantitatively the content of berberine and total alkaloid content in all Cortex Phellodendri samples. Three alkaloids, berberine, jatrorrhizine and palmatine were analyzed simultaneously with a Thermo ODS Hypersil column by gradient elution with a new mobile phase under high-performance liquid chromatography-diode array detection (HPLC-DAD). Berberine content determined by HPLC-DAD was exploited as a critical parameter for successful discrimination between them. Multiplicative scatter correction (MSC), second derivative and Savitsky-Golay (S.G.) were utilized together to correct the scattering effect and eliminate the baseline shift in all near infrared diffuse reflectance spectra as well as to enhance spectral features in order to give a better correlation with the results obtained by HPLC-DAD. With the use of principal component analysis (PCA), samples datasets were separated successfully into two different clusters corresponding to two species. Furthermore, a partial least squares (PLS) regression method was built on the correlation model. The results showed that the correlation coefficients of the prediction models were R = 0.996 for the berberine and R = 0.994 for total alkaloid content. The influences of water absorption bands present in the NIR spectra on the models were also investigated in order to explore the practicability of NIRS in routine use. The outcome showed that NIRS possibly acts as routine screening in the quality control of Chinese herbal medicine.  相似文献   
10.
A consecutive preparation method based upon accelerated solvent extraction (ASE) coupled with high‐speed counter‐current chromatography (HSCCC) was presented and aesculin was obtained from Cortex fraxinus. The extraction condition of ASE was optimized with response surface methodology; some significant parameters such as the solvent system and its stability, the amount of loading sample in HSCCC were also investigated. The original sample was first extracted with methanol at 105°C and 104 bar for 7 min using ASE, then the extracts were consecutively introduced into the HSCCC system and separated and purified with the same ethyl acetate/n‐butanol/water (7:3:10, v/v/v) solvent system for five times without further exchange and equilibrium. About 3.1 ± 0.2 mg/g in each time and total of 15.4 mg/g aesculin with purity over 95% was isolated from Cortex fraxinus. The results demonstrated that the consecutive preparation method was time and solvent saving and high throughput, it was suitable for isolation of aesculin from Cortex fraxinus, and also has good potential on the separation and purification of effective compounds from natural product.  相似文献   
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