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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.
《Analytical letters》2012,45(5-6):460-472
Interest in ionic liquids (ILs) for their potential in analytical chemistry is increasing because they are environmentally benign and are good separation solvents. The aim of the presented investigation was to verify whether ILs would be a suitable background electrolyte (BGE) in nonaqueous capillary electrophoresis (NACE) for organic cations analysis of the closely related analogues. In this study, a novel and very simple NACE method has been established for analyzing seven quaternary alkaloids in Coptis rhizome using 1-alkyl-3-methylimidazolium tetrafluoroborate-based ionic liquid as BGE. The effects of the alkyl group, imidazolium counterion (anionic part), along with the concentration of IL, are investigated and discussed. Baseline separation, high efficiencies, and symmetrical peaks of the seven alkaloids were obtained. The separation mechanism could be hydrophobic and hydrogen-bonding interactions between the alkaloids and the imidazolium cations. The optimum conditions were 70 mM 1-decyl-3-methylimidazolium tetrafluoroborate (1D-3MI-TFB) methanol solution (apparent pH 2.66) and 30 kV applied voltage. The detection was performed at 254 nm. Seven quaternary alkaloids in Coptis rhizome were separated within 14 min. The proposed NACE separation procedure is highly reproducible and can be applied in the qualitative and quantitative analysis of Coptidis alkaloids.  相似文献   
3.
为了建立黄连色度测量方法并分析其与有效成分含量之间的相关性,应用灰色关联分析(GRA)与主成分分析(PCA)对不同产地黄连药材进行质量评价。收集了来自15个不同产区黄连药材,依据国际照明委员会CIE L*a*b*数字化系统,采用分光测色计测定15批黄连药材色度值,采用高效液相色谱(HPLC)测定表小檗碱、黄连碱、巴马汀和盐酸小檗碱4种生物碱含量,并运用SPSS 23.0软件对色度与生物碱含量进行相关性分析。将黄连药材中生物碱类成分含量、药材水分、灰分、浸出物含量及色度值作为考察指标,采用GRA法构建黄连质量评价模型并采用SIMCA-P 14.1软件进行PCA及正交偏最小二乘法分析;结果表明,色度测量方法准确可靠;相关性分析结果显示,黄连色度L*a*b*Eab* (总色度值)值与表小檗碱、黄连碱、巴马汀和盐酸小檗碱的含量均有显著相关性。GRA分析结果显示,产地为重庆市的黄连与最优参考序列的相对关联度最高、质量最优;PCA分析结果显示产地为陕西省铜川市的黄连对主成分贡献率较高。GRA与色度测定所建立的黄连质量评价模型可作为黄连药材质量评价的参考依据。  相似文献   
4.
A capillary electrophoretic method for simultaneous determination of six bioactive ingredients (berberine, palmatine, baicalin, sennoside B, emodin, and sennoside A) in the Chinse herbal formula San-huang-hsieh-hsin-tang was established. A carrier composed of aqueous buffer solution (50 mM sodium cholate, 15 mM sodium dihydrogen phosphate, and 4.25 mM sodium borate)-acetonitrile (3:2) was found to be the most suitable electrolyte for this separation. Contents of these constituents in a non-pretreated methanol-water extract of San-huang-hsieh-hsin-tang sample could be easily determined within 20 min. The effects of borate, cholate, and organic modifier (acetonitrile) concentration of the carrier on the migration behavior of the solutes were also studied.  相似文献   
5.
Magnoflorine, an important aporphine alkaloid in Coptidis Rhizoma, is increasingly attracting research attention because of its pharmacological activities. The in vivo and in vitro metabolism of magnoflorine was investigated by LC LTQ‐Orbitrap MS. In vivo samples including rat urine, feces, plasma and bile were collected separately after both oral (50 mg kg?1) and intravenous administration (10 mg kg?1) of magnoflorine, along with in vitro samples prepared by incubating magnoflorine with rat intestinal flora and liver microsome. As a result, 12 metabolites were found in biological samples. Phase I metabolites were identified in all biological samples, while phase II metabolites were mainly detected in urine, plasma and bile. In a pharmacokinetic study, rats were not only dosed with magnoflorine via oral (15, 30 and 60 mg kg?1) and intravenous administration (10 mg kg?1) but also dosed with Coptidis Rhizoma decoction (equivalent to 30 mg kg?1 of magnoflorine) by intragastric administration to investigate the interaction of magnoflorine with the rest of compounds in Coptidis Rhizoma. Studies showed that magnoflorine possessed lower bioavailability and faster absorption and elimination. However, pharmacokinetic parameters altered significantly (p < 0.05) when magnoflorine was administered in Coptidis Rhizoma decoction. Oral gavage of Coptidis Rhizoma decoction decreased the absorption and elimination rates of magnoflorine, which revealed that there existed pharmacokinetic interactions between magnoflorine and the rest of ingredients in Coptidis Rhizoma. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
6.
Simple, convenient, sensitive and accurate analytical methods are needed for the structural characterization and identification of alkaloid components in Rhizoma Coptidis in traditional Chinese herbal medicine, which has important bioactivity. In this work, the identification of alkaloid compounds in Rhizoma Coptidis was investigated by obtaining molecular mass information using electrospray ionization mass spectrometry (ESI-MS). Multi-stage tandem mass spectrometric (ESI-MS(n)) data for the alkaloid compounds were used for detailed structural characterization, then structure information was obtained by comparison of the fragmentation mechanisms of both alkaloids in Rhizoma Coptidis and standard samples of berberine, palmatine, coptisine and jatrorrhizine by MS. Based on the results obtained, the structure of a novel compound was elucidated. The results of the experiments demonstrate that ESI-MS(n) is a sensitive, selective and effective tool for the rapid determination of alkaloids in Rhizoma Coptidis.  相似文献   
7.
In this study, we propose an integrated strategy for the efficient identification and quantification of herbal constituents using liquid chromatography with mass spectrometry. First, liquid chromatography with quadrupole time‐of‐flight mass spectrometry was employed for the chemical profiling of herbs, where a targeted following nontargeted approach was developed to detect trace constituents by using structural correlations and extracted ion chromatograms. Next, ion pairs and parameters of MS2 of quadrupole time‐of‐flight mass spectrometry were selected to design multiple reaction monitoring transitions for the identified compounds on liquid chromatography with triple quadrupole mass spectrometry. The relative concentration of each constituent was then calculated using a semiquantitative calibration curve. The proposed strategy was applied in a study of chemical interactions between Glycyrrhizae Radix and Coptidis Rhizoma. A total of 140 compounds were identified or tentatively characterized from the herbs, 132 of which were relatively quantified. The visualized quantitative results clearly showed codecoction produced significant constituent concentration variations especially for those with a low polarity. The case study also indicated that the present methodology could provide a reliable, accurate, and labor‐saving solution for chemical studies of herbal medicines.  相似文献   
8.
This study aims to qualitatively analyze protoberberine alkaloids in crude extract of Coptidis Rhizoma using HPLC with ESI‐MS/MS. Possible specific molecular weights of protoberberine alkaloids were firstly deduced according to literatures and were adopted to screen the alkaloids in the HPLC with ESI‐MS of crude extract of Coptidis Rhizoma. As a result, 21 protoberberine alkaloids were found, including compounds of very low concentration and compounds coeluted in one peak. Among these, two compounds were positively identified and verified by comparison with standards. Ten of these compounds were first reported in this study for Coptidis Rhizoma. In addition, chromatographic retention parameters a and c of all compounds were obtained using their retention times under five gradient conditions and were applied to confirm the deduction about the structures of protoberberine alkaloids by tandem mass data.  相似文献   
9.
应用电化学指纹图谱优化黄连水提取工艺的研究   总被引:9,自引:1,他引:8  
以黄连提取液中的总成分为定量指标,应用电化学振荡技术获取不同提取工艺的电化学指纹图谱.根据电化学指纹图谱特征参数诱导时间来考察其水溶性有效成分含量的高低,与高效液相色谱含量测定方法对照,验证了该方法的可靠性,确定黄连提取的最佳工艺为:采用12倍量的水,提取1.5 h,提取2次.结果表明利用电化学指纹图谱的诱导时间优化中药水溶性有效成分的提取工艺是可行的.  相似文献   
10.
采用微量热法研究和比较中药黄连中四种生物碱(BAs)的抗菌(大肠杆菌)作用。这四种生物碱分别为小檗碱、黄连碱、巴马汀和药根碱。用LKB-2277生物活性检测系统,以停留法测定了37 ℃时大肠杆菌在BAs作用下的热流功率-时间曲线,并记录生长速率常数k, 指数生长期和稳定期的最大热功率Pm, log、Pm, stat, 生长抑制率I, 传代时间tg,指数生长期的总产热量Qt, log,半数抑菌浓度IC50等热动力学参数。结果显示这四种生物碱具有相异的抗大肠杆菌生长代谢的作用,k, Pm, log和Qt, log值随BAs浓度的增加而相应的减少。综合分析k, Pm, log, Qt, log, I 和IC50值可以看出,BAs抑制大肠杆菌生长代谢强度按小檗碱、黄连碱、巴马汀、药根碱的顺序依次减弱。构效关系研究表明,母环C-2和C-3上连接的亚甲二氧基比甲氧基更能显著增强相应化合物的抗菌作用,而C-9和C-10上连接的亚甲二氧基或甲氧基对这种抗菌作用影响不大。  相似文献   
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