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1.
怀菊花中微量铁的测定   总被引:5,自引:3,他引:2  
为探讨邻二氮菲分光光度法测定怀菊花中微量元素铁含量的可行性,怀菊花的药理功效、食用营养价值与微量元素含量可能存在的关系,根据铁离子与特定显色剂显色产生可见吸收,采用混合酸y(HNO3):V(HClO4)=4+1对怀菊花样品湿法消化处理,在pH2~9的溶液中试剂与铁生成稳定的橙色络合物,并用分光光度法测定了怀菊花中微量元素铁含量。结果表明,所选的怀菊花中铁含量303.9~337.9μg/g,加标回收率为90.2%~100.6%。分光光度法操作简便、干扰离子少,测量快速、结果准确度和灵敏度高,易推广和 普及使用。  相似文献   
2.
3种菊花茶中6种微量元素的初级形态及溶出特性研究   总被引:4,自引:1,他引:3  
杨义钧 《光谱实验室》2009,26(4):959-962
按照传统的花茶饮用方法对杭白菊茶、野菊花茶、贡菊茶3种菊花茶中钙、镁、铁、锰、铜、锌6种元素进行浸取;用0.45μm微孔滤膜分离浸取液中的可溶态和悬浮态;采用电感耦合等离子体原子发射光谱法对此3种菊花茶中微量元素的初级形态进行了测定。结果显示:菊花茶中6种元素的提取率在12.4%—80.4%之间,可溶态在水浸液中的比率在74.3%—96.5%之间。  相似文献   
3.
Two new guaianolides (=guaianolactones), chrysanthguaianolactone A and B ( 1 and 2 , resp.), and one new eudesmane sesquiterpene, chrysanthemdiol A ( 6 ), together with seven known sesquiterpenes were isolated from the flowers of Chrysanthemum indicum L. Their structures were elucidated on the basis of spectroscopic evidence.  相似文献   
4.
The widespread use of insecticides in Chinese herbal medicines has created a compelling need for the development of a multiresidue analytical method to help assure herbs safety. The operating variables affecting the performance of the multiresidue analysis of 34 organochlorine and 12 pyrethroid pesticides in chrysanthemum, a widely used kind of Chinese herbal medicines, were evaluated. Three different extraction solvents including n‐hexane and its mixtures with acetone and petroleum ether were compared, and n‐hexane was found to be an appropriate option. A combination of gel permeation chromatography and SPE was selected as the optimum cleanup, in comparison with dispersive SPE, or the two former methods alone. The determination of the 46 pesticide residues in the spiked chrysanthemum samples was performed by GC with electron capture detection. The average recoveries ranged from 71.3 to 102.6% with RSDs of 1.4–15.7% for all of the pesticides. The LOQs were in the range of 0.0015–0.2 mg/kg, while the LODs were between 0.0005 and 0.1 mg/kg. The satisfactory accuracy, and precision, in combination with a good separation and few interferences, have demonstrated the strong potential of this technique for its application in chrysanthemum analysis.  相似文献   
5.
GC/MS 法测定超临界 CO2 萃取茼蒿籽油   总被引:2,自引:0,他引:2  
利用GC/MS分析了超临界CO2萃取茼蒿籽油的成分组成,共检出32种成分。茼蒿籽油主要由亚油酸(含量68.32%)、棕榈酸(10.80%)、油酸(6.39%)和长碳链脂肪酸组成;茼蒿籽油还含甾类(4.76%)和丰富的维生素E(3.9mg/g);研究了茼蒿籽油的理化特征。  相似文献   
6.
子午岭野菊花挥发油的化学成分及抑菌活性   总被引:7,自引:0,他引:7  
利用GC—MS联用法对野菊花挥发油的化学成分进行了分析研究.在最佳分析条件下.共分离出39个化学成分.鉴定出了其中的38个.主要成分为:萜类、酚类、有机酸及其酯等化合物.对挥发油的抗菌活性进行了初步研究.为今后对野菊花药理活性的研究提供了重要的理论依据.  相似文献   
7.
A simple and rapid high‐performance thin‐layer chromatographic method was developed for the separation and determination of six flavonoids (rutin, luteolin‐7‐O‐β‐glucoside, chamaemeloside, apigenin‐7‐O‐β‐glucoside, luteolin, apigenin) and one coumarin, umbelliferone from chamomile plant samples and dietary supplements. The separation was achieved on amino silica stationary phase using dichloromethane/acetonitrile/ethyl formate/glacial acetic acid/formic acid (11:2.5:3:1.25:1.25 v/v/v/v/v) as the mobile phase. The quantitation of each compound was carried out using densitometric reflection/absorption mode at their respective absorbance maxima after postchromatographic derivatization using natural products reagent (1% w/v methanolic solution of diphenylboric acid‐β‐ethylamino ester). The method was validated for specificity, limits of detection and quantification, precision (intra‐ and interday) and accuracy. The limits of detection and quantification were found to be in the range from 6–18 and 16–55 ng/band for six flavonoids and one coumarin, respectively. The intra‐ and interday precision was found to be <5% RSD and recovery of all the compounds was >90%. The data acquired from high‐performance thin‐layer chromatography was processed by principal component analysis using XLSTAT statistical software. Application of principal component analysis and agglomerative hierarchial clustering was successfully able to differentiate two chamomiles (German and Roman) and Chrysanthemum.  相似文献   
8.
Flos Chrysanthemi, dried flower of Chrysanthemum morifolium Ramat, has drawn much attention recently owing to its potential beneficial health effects for human. Flos Chrysanthemi products are usually taken orally and metabolized by intestinal microflora. However, there has been no investigation of the comprehensive metabolic profile of the Flos Chrysanthemi extract by intestinal flora owing to its chemical complexity and the limitations of analytical methods. In this paper, a rapid, sensitive and automated analysis method, ultra‐performance liquid chromatography/quadrupole time of flight mass spectrometry including MSE technology and automated data processing Metabolynx? software, was developed and successfully applied for the biotransformation and metabolic profile of flavonoids in the Flos Chrysanthemi extract by intestinal flora from human and rat. A total of 32 metabolites were detected and tentatively identified in human and rat intestinal bacterial samples. These metabolites indicated that hydrolysis, hydroxylation, acetylation, methylation, hydrogenation and deoxygenation were the major conversion pathways of flavonoids in the Flos Chrysanthemi extract in vitro. Furthermore, the effects of the Flos Chrysanthemi extract on the growth of different intestinal bacteria were detected using an Emax precision microplate reader. Certain pathogenic bacteria such as Enterobacter, Enterococcus, Clostridium and Bacteroides were significantly inhibited by Flos Chrysanthemi, while commensal probiotics such as Lactobacillus and Bifidobacterium were moderately promoted. Our observation provided further evidence for the importance of intestinal bacteria in the metabolism and potential activity of the Flos Chrysanthemi extract. The results will also be helpful for the further pharmacokinetic study of Flos Chrysanthemi and to unravel how it works in vivo.  相似文献   
9.
野菊花中性多糖CIP-C的分离纯化及结构解析   总被引:1,自引:0,他引:1  
以野菊花为原材料, 经热水提取、乙醇沉淀、DEAE-Sepharose Fast Flow和Sephacryl S-200 凝胶柱层析分离纯化, 得到1个水溶性的中性多糖CIP-C. 采用GC-MS、部分酸水解及甲基化分析等对该多糖的结构进行了解析. 结果表明, 该多糖主要由D-Man, D-Glc和D-Gal组成, 并含有少量的D-Fuc, L-Ara和D-Xyl, 其主链由β(或α)-D-1,4-Man, β-D-1,6-Glc和β-D-1,4-Gal组成, 而阿拉伯糖通过α-L-T-Araf和α-L-1,5-Araf连接形成阿拉伯聚糖支链或与β-D-1,4-Galp的O3位相连形成阿拉伯半乳聚糖支链.  相似文献   
10.
《Analytical letters》2012,45(12):2023-2034
Flos Chrysanthemum is a generic name for a particular group of edible plants, which also have medicinal properties. There are, in fact, twenty to thirty different cultivars, which are commonly used in beverages and for medicinal purposes. In this work, four Flos Chrysanthemum cultivars, Hangju, Taiju, Gongju, and Boju, were collected and chromatographic fingerprints were used to distinguish and assess these cultivars for quality control purposes. Chromatography fingerprints contain chemical information but also often have baseline drifts and peak shifts, which complicate data processing, and adaptive iteratively reweighted, penalized least squares, and correlation optimized warping were applied to correct the fingerprint peaks. The adjusted data were submitted to unsupervised and supervised pattern recognition methods. Principal component analysis was used to qualitatively differentiate the Flos Chrysanthemum cultivars. Partial least squares, continuum power regression, and K-nearest neighbors were used to predict the unknown samples. Finally, the elliptic joint confidence region method was used to evaluate the prediction ability of these models. The partial least squares and continuum power regression methods were shown to best represent the experimental results.  相似文献   
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