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21.
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   
22.
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   
23.
张海英  赵泳波 《光谱实验室》2013,30(5):2335-2338
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   
24.
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   
25.
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   
26.
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   
27.
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   
28.
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   
29.
RP-HPLC测定大别山区不同产地天麻药材中天麻素含量研究   总被引:1,自引:0,他引:1  
忻晹  陈龙胜  陈涛  蔡群兴  周斌 《光谱实验室》2005,22(6):1185-1187
采用RP-HPLC外标曲线法测定了天麻原药材中天麻素含量,色谱柱为Phenomenex-C18(4.6mm×250mm,5μm);流动相乙腈-水(5∶95);检测波长225nm。流速0.5mL·min-1:柱温27℃。结果表明天麻素在0.1000—0.6000μg呈良好线性关系,r=0.9997,平均加样回收率为99.53%,RSD为1.7%。方法灵敏、快速、准确,可用于天麻中天麻素含量的测定。  相似文献   
30.
研究了离子液体分散液相微萃取(ILDLPME)机理, 建立了简单、快速、灵敏的ILDLPME-HPLC(高效液相色谱)同时测定中药白附子中5种低丰度苯丙烯酸类化合物含量的方法, 对不同产地白附子的质量进行了比较和评价. 在最佳的ILDLPME-HPLC条件下, 测得咖啡酸的线性范围为1.28×10-3~2.60 μg/mL, 对羟基桂皮酸及阿魏酸的线性范围为1.28×10-4~2.60 μg/mL, 桂皮酸及对甲氧基桂皮酸的线性范围为1.28×10-3~4.00 μg/mL, 检出限分别为0.13, 0.01, 0.01, 0.13和0.13 ng/mL, 日内精密度RSD<7.9%, 日间精密度RSD<9.7%, 药材中分析物的回收率在86.9%~112.6%之间, ILDLPME 对5种分析物的富集倍数分别在56.0~159.3倍之间. 结合5种苯丙烯酸类化合物ILDLPME萃取前后紫外光谱的变化, 提出了ILDLPME萃取苯丙烯酸羧基-离子液体电荷转移超分子(CTSMCIL)机理. 本研究为建立中药白附子的质量控制方法提供了理论依据和实验基础.  相似文献   
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