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71.
A rapid and sensitive CEC method with methacrylate ester‐based monolithic column has been developed for separation and determination of five coumarins (byakangelicin, oxypeucedanin hydrate, xanthotoxol, 5‐hydroxy‐8‐methoxypsoralen and bergapten) in Angelica dahurica extract. Surfactant sodium desoxycholate (SDC) was introduced into the mobile phase as the pseudostationary to dynamically increase the selectivity of analytes instead of increasing the hydrophobicity of stationary phase. In addition, other factors, pH of phosphate buffer, ACN content and applied voltage, for instance, have also an obvious effect on the resolution but little on the retention time. Satisfactory separation of these five coumarins was achieved within 6 min under a 30:70 v/v ACN–buffer containing 20 mM sodium dihydrogen phosphate (NaH2PO4) and 0.25 mM SDC at pH 2.51. The RSDs of intraday and interday for relative peak areas were less than 3.0% and 4.7%, respectively; and the recoveries were between 87.5% and 95.0%. The LODs were lower than 0.15 μg/mL and the LOQs were lower than 0.30 μg/mL, respectively, while calibration curves showed a good linearity (r2 > 0.9979). Finally, five target coumarins from the crude extracts of A. dahurica were separated, purified, and concentrated by D‐101 macroporous resin, and were successfully separated and quantitatively determined within 6 min. 相似文献
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In this work, a simple, rapid, solvent-free, and low-cost method was developed for the determination of ligustilides in traditional Chinese medicines (TCMs), which was based on pressurized hot water extraction (PHWE) followed by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). The two bioactive compounds Z-ligustilide and E-ligustilide in two common TCMs, viz. Ligusticum chuanxiong and Angelica sinensis, were extracted by water at 150 degrees C and 40 bar, followed by concentration with HS-SPME and detection by GC-MS. PHWE and HS-SPME parameters were investigated and method validation (precision and recovery) was studied. It has been shown that the proposed method provides a powerful approach for quantitative analysis of ligustilides in TCMs. The method was applied to determination of ligustildes in the TCMs from different growing areas. The results indicate that PHWE-HS-SPME-GC-MS is a potential tool for TCM quality assessment. 相似文献
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Xing Zeng Zhao Xu Feng Xiao Dong Jia Yun Fa Dong Ming Wang Jiangsu Center for Research & Development of Medicinal Plants Jiangsu Institute of Botany Chinese Academic of Science/Nanjing Botanical Garden Mem. Sun Yat-Sen. Nanjing China 《中国化学快报》2007,18(2):168-170
A new neolignan glycoside, 4-O-β-D-glucopyranosyl-9-O-β-D-glucopyranosyl-(7R,8S)-dehydrodiconiferyl alcohol was isolated from the fresh roots of Angelica dahurica. The structure of the new compound was elucidated on the basis of spectral analysis. 相似文献
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以甲基丙烯酸酯整体柱为分离柱,建立了一种快速分离、分析白芷药材提取物中的主要活性成分欧前胡素(imperatorin)、异欧前胡素(isoimperatorin)、珊瑚菜内酯(phelloptorin)和发卡二醇(falcarindiol)的毛细管电色谱(CEC)方法。在整体柱制备实验中对三元致孔剂组成成分的比例进行了系统的考察。在分离实验中对流动相的组成(包括有机相组成、缓冲液浓度和缓冲液的pH值)进行了优化。最终的优化条件为: 流动相为乙腈-20 mmol/L NaH2PO4(pH 4.95)(50:50, v/v),分离电压为-25 kV。结果表明,所制备的甲基丙烯酸酯毛细管整体柱具有良好的渗透性和重现性;4种分析物的标准曲线线性关系良好(r2>0.997),检出限均小于0.34 mg/L,加样回收率为95.18%~98.44%。该方法快速、简便、可靠。应用该方法对18个不同产地的白芷样品进行了测定,并对其药材质量进行了评价。 相似文献
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白芷叶中分泌道显微和超微结构的研究 总被引:1,自引:0,他引:1
本文对白芷叶中分泌道的显微和超微结构进行了研究。白芷叶中分泌道是由一层上皮细胞围绕一圆形腔道而成,分布于叶片、叶鞘和叶柄的薄壁组织及较大叶脉或维管组织的次生韧皮部中,分泌道的发生方式为裂生型,其腔隙的扩大主要依靠上皮细胞本身的分裂生长以及周围细胞插入到上皮细胞之间。电镜观察结果表明分泌道原始细胞之间裂开形成腔隙可能与高尔基体分泌果胶酶进入到相邻细胞壁间而导致中层溶解有关,成熟分泌道上皮细胞中含有丰富的质体和内质网,其中大多数质体被内质网鞘所围绕,分泌道发育过程中上皮细胞超微结构最显著变化是质体、内质网和嗜锇滴数量的改变,它们随着分泌道的成熟而增加,随着分泌道的衰老而减少,嗜锇物质主要由质体、鞘内质网和细胞质内质网合成,而线粒体、液泡和细胞质也可参与分泌物的合成和运输过程 相似文献
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Kazuhiro Sugamoto Yoh-ichi MatsusitaKana Matsui Chiaki KurogiTakanao Matsui 《Tetrahedron》2011,67(29):5346-5359
Chalcones bearing prenyl or geranyl groups from Angelica keiskei, such as 4-hydroxyderricin (1a), xanthoangelol (1e), xanthoangelol F (1f), xanthoangelol H (2), deoxyxanthoangelol H (3), and deoxydihydroxanthoangelol H (4) and their derivatives were synthesized. From the evaluation of antibacterial activity of the synthesized chalcones, 1a, isobavachalcone (1b), 1e, 1f, bavachalcone (5a), and broussochalcone B (5b) were found to inhibit Gram-positive bacteria. 相似文献
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Han Dong Meiling Li Ling Jin Xiaorong Xie Mengfei Li Jianhe Wei 《Molecules (Basel, Switzerland)》2022,27(1)
Angelica sinensis, a perennial herb that produces ferulic acid and phthalides for the treatment of cardio-cerebrovascular diseases, prefers growing at an altitude of 1800–3000 m. Geographical models have predicted that high altitude, cool temperature and sunshade play determining roles in geo-authentic formation. Although the roles of altitude and light in yield and quality have been investigated, the role of temperature in regulating growth, metabolites biosynthesis and gene expression is still unclear. In this study, growth characteristics, metabolites contents and related genes expression were investigated by exposing A. sinensis to cooler (15 °C) and normal temperatures (22 °C). The results showed that plant biomass, the contents of ferulic acid and flavonoids and the expression levels of genes related to the biosynthesis of ferulic acid (PAL1, 4CLL4, 4CLL9, C3H, HCT, CCOAMT and CCR) and flavonoids (CHS and CHI) were enhanced at 15 °C compared to 22 °C. The contents of ligustilide and volatile oils exhibited slight increases, while polysaccharide contents decreased in response to cooler temperature. Based on gene expression levels, ferulic acid biosynthesis probably depends on the CCOAMT pathway and not the COMT pathway. It can be concluded that cool temperature enhances plant growth, ferulic acid and flavonoid accumulation but inhibits polysaccharide biosynthesis in A. sinensis. These findings authenticate that cool temperature plays a determining role in the formation of geo-authentic and also provide a strong foundation for regulating metabolites production of A. sinensis. 相似文献