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排序方式: 共有156条查询结果,搜索用时 31 毫秒
21.
ABSTRACT Rhizoma cyperi (tuberal part of Cyperus rotundus Linn) obtained from 15 different zones of China was studied to determine the contents of 16 trace elements such as 4 minor (Ca, K, Mg, and Na), 9 trace (Co, Cr, Cu, Fe, Mn, Mo, Ni, V, and Zn), and 3 toxic (Ag, Cd, and Pb) elements. The concentration determination of 16 elements was performed by atomic absorption spectrophotometry (AAS) after microwave-assisted digestion. A microwave-assisted digestion procedure based on the mixture nitric acid–hydrogen peroxide was evaluated. The method was successfully validated with the good recoveries (97–105%) against CRM GBW07603 (bush twigs and leaves). The calibration curve furnished good linear correlation coefficients (r = 0.9956–0.9999), excellent recoveries (99.35–103.7%), and limits of detection (LOD = 1–50 ng·mL?1) suitable to determine in Rhizoma cyperi. The results showed that K, Ca, Mg, and Na were the most abundant of the major elements in Rhizoma cyperi with average concentrations of K, 26,221 µg·g?1; Ca, 1097 µg·g?1; Mg, 714 µg·g?1, and Na, 293 µg·g?1, respectively. K element was determined for the first time in this plant. 相似文献
22.
23.
The main constituents, senkyunolide A, Z-ligustilide, neocnidilide, 3-butylphthalide, and ligustilide dimers, in supercritical
CO2 fluid extracts of Rhizoma Chuanxiong, a popular Chinese traditional medicine, have been identified and characterized by high
performance liquid chromatography tandem mass spectrometry. Separations were carried out on an Agilent (ECLIPSE XDB) C18 analytical
column by gradient elution with 0.25% acetic acid and methanol (containing 0.25% acetic acid). An Agilent 1100 series LC/MSD
XCT system was operated under positive ESI and auto MS/MS modes for mass spectrometric analysis. Collision-induced dissociation
(CID) fragmentations of these phthalides have been investigated and elucidated. Phthalides have primarily undergone two ESI
CID pathways: side-chain cleavage with losses of alkenes and ring-opening with eliminations of H2O followed by losses of CO. Direct neutral loss of CO has not been observed. Sodium adduct ions have demonstrated completely
different CID pathways.
__________
Translated from Journal Instrumental Analysis (in press, in Chinese) 相似文献
24.
Screening and analysis of an antineoplastic compound in Rhizoma Chuanxiong by means of in vitro metabolism and HPLC-MS 总被引:1,自引:0,他引:1
A new screening and analysis method that combines in vitro metabolism with high-performance liquid chromatography-mass spectrometry
(HPLC-MS) was developed for the screening and analysis of an antineoplastic compound, coniferyl ferulate, which is present
in the rhizome of Rhizoma Chuanxiong. Infrared (IR), ultraviolet visible spectroscopy (UV-Vis), nuclear magnetic resonance (NMR) and element analysis were used
to identify the molecular structure of coniferyl ferulate. The quantitative analysis of coniferyl ferulate in different extracts
of Rhizoma Chuanxiong was carried out, and the metabolism of coniferyl ferulate was investigated by in vitro incubation with rat liver homogenate.
The metabolite of coniferyl ferulate, ferulic acid ethyl ester, was identified by HPLC-MS, UV-Vis and IR. In addition, antineoplastic
activities of coniferyl ferulate and ferulic acid ethyl ester were detected by the MTT assay. The observed inhibition rate
of coniferyl ferulate on the activity of HeLa cells was over 80% at 5.4 ng μl−1. However, its metabolite, ferulic acid ethyl ester, showed no antineoplastic activity in vitro.
相似文献
25.
采用高效液相色谱法测定丹参超微粉体和常规粉体中丹参酮ⅡA体外溶出量和溶出速率.丹参超微粉体和常规粉体中丹参酮ⅡA体外溶出量无显著性差异,超微粉体的溶出速率较常规粉体明显增加.实验表明超微粉碎可明显提高丹参酮ⅡA溶出速率. 相似文献
26.
Dan Dan Yin Yun Lai Wang Mo Yang Deng Ke Yin Guo Kai Wang Fan Xu 《Journal of separation science》2019,42(19):3067-3076
Ligustrazine was the active ingredient of the traditional Chinese medicine Chuanxiong Rhizoma. However, the content of ligustrazine is very low. We proposed a hypothesis that ligustrazine was produced by the mutual effects between endophytic Bacillus subtilis and the Ligusticum chuanxiong Hort. This study aimed to explore whether the endophytic B. subtilis LB5 could make use of Chuanxiong Rhizoma fermentation matrix to produce ligustrazine and clarify the mechanisms of action preliminarily. Ultra high performance liquid chromatography with quadrupole time‐of‐flight mass spectrometry analysis showed the content of ligustrazine in Chuanxiong Rhizoma was below the detection limit (0.1 ng/mL), while B. subtilis LB5 produced ligustrazine at the yield of 1.0268 mg/mL in the Chuanxiong Rhizoma‐ammonium sulfate fermentation medium. In the fermented matrix, the reducing sugar had a significant reduction from 12.034 to 2.424 mg/mL, and rough protein content increased from 2.239 to 4.361 mg/mL. Acetoin, the biosynthetic precursor of ligustrazine, was generated in the Chuanxiong Rhizoma‐Ammonium sulfate (151.2 mg/mL) fermentation medium. This result showed that the endophytic bacteria B. subtilis LB5 metabolized Chuanxiong Rhizoma via secreted protein to consume the sugar in Chuanxiong Rhizoma to produce a considerable amount of ligustrazine. Collectively, our preliminary research suggested that ligustrazine was the interaction product of endophyte, but not the secondary metabolite of Chuanxiong Rhizoma itself. 相似文献
27.
《Journal of separation science》2018,41(11):2310-2320
We established a rapid and sensitive ultra high‐performance liquid chromatography tandem mass spectrometry method for the simultaneous quantification of xanthones and steroidal saponins in rat plasma. Chromatographic separation was achieved on a C18 column with a mobile phase comprising acetonitrile and 0.1% formic acid. The detection was performed by negative electrospray ionization in multiple reaction monitoring mode. The validated method showed good linearity within the tested range (r > 0.9945). The intra‐ and interday precision at high, medium, and low concentrations was less than 7.96%. The bias of accuracies ranged from −1.92 to 9.62%. The extraction recoveries of the compounds ranged from 84.78 to 88.69%, and the matrix effects ranged from 96.76 to 108.59%. This method was successfully applied to a pharmacokinetic comparison of crude and salt‐processed Anemarrhenae Rhizoma aqueous extracts after oral administration in rats. The maximum plasma concentration and area under concentration–time curve of timosaponin BIII and timosaponin AIII increased significantly (P < 0.05 or 0.01) and those of timosaponin BII decreased significantly (P < 0.05) after processing. These results could contribute to the clinical application of crude and salt‐processed Anemarrhenae Rhizoma and reveal the processing mechanism. 相似文献
28.
为了准确测定黄精中稀土元素的含量,采用电感耦合等离子体质谱(ICP-MS)法同时测定黄精中15种稀土元素(La、Ce、Pr、Nd、Pm、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu)的含量,进而绘制稀土元素指纹图谱,以稀土元素含量的平均值构建黄精稀土元素标准指纹图谱,作为鉴定黄精中药材的参考依据。黄精样品采用微波消解法处理后,通过在线引入内标溶液,采用ICP-MS法测定15种稀土元素的含量,采用OriginPro 2021绘制稀土元素指纹图谱和进行主成分分析,采用SPSS 26.0进行聚类分析。15种稀土元素的线性关系、重复性、精密度良好,平均加标回收率在97.0%~103.3%,相对标准偏差小于等于1.74%。黄精中Ce、La、Nd含量相对较高,Ce含量为53.02~2004.58 μg/kg,位居第一。聚类分析和主成分分析结果表明,样品聚为2类,同一产地的样品能够较好地聚在一起。黄精药材中15种稀土元素的指纹图谱具有相似的分布形态,具有较强的特征性和一致性,相似度均大于0.950。该方法操作简单,准确可靠,能满足实验分析要求,可为黄精的质量控制和药理研究提供参考;建立的指纹图谱可用于黄精的鉴别。 相似文献
29.
A liquid chromatography-mass spectrometry method is presented for the quantification of C21 steroids in the roots and rhizomes of Cynanchum paniculatum. Eight C21 steroids, including five steroidal aglycones and three steroidal glycosides, were simultaneously analyzed by liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry. The extracted ion current chromatograms were extracted from the total ion current chromatogram using characteristic ions produced by target compounds for peak determination. Chromatographic separation was achieved on a C18 reversed-phase column within 60 min, using an acetonitrile/water gradient. For comparision, six C. paniculatum samples from different locations were investigated by the established method, and the results indicated that the different geographical origin significantly influenced the C21 steroid composition. The method was observed to have the necessary sensitivity, selectivity, precision, and accuracy, and to be suitable for quality control of herbal medicines and their preparations. 相似文献
30.
A method for the quality evaluation of Atractylodis Macrocephalae Rhizoma (AMR) based on high-performance liquid chromatography (HPLC) fingerprint, HPLC quantification, and chemical pattern recognition analysis was developed and validated. The fingerprint similarity of the 27 batches of AMR samples was 0.887–0.999, which indicates there was very limited variance between the batches. The 27 batches of samples were divided into two categories according to cluster analysis (CA) and principal component analysis (PCA). A total of six differential components of AMR were identified in the partial least-squares discriminant analysis (PLS-DA), among which atractylenolide I, II, III, and atractylone counted 0.003–0.045%, 0.006–0.023%, 0.001–0.058%, and 0.307–1.175%, respectively. The results indicate that the quality evaluation method could be used for quality control and authentication of AMR. 相似文献