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为探讨杜仲不同药用部位(杜仲、杜仲叶和杜仲雄花)化学成分的差异,采用液相色谱-串联三重四极杆飞行时间高分辨质谱(LC-Triple TOF MS/MS)结合多元统计分析技术对杜仲不同药用部位的化学成分进行差异分析。通过对多级串联质谱数据进行峰匹配、峰对齐、滤噪处理等分析,提取特征峰;用聚类分析(HCA)、主成分分析(PCA)和偏最小二乘法-判别分析(PLS-DA)进行数据处理;通过一级质谱精确质荷比和二级质谱碎片信息,结合软件数据库搜索、标准品比对及相关文献进行成分鉴定。结果显示:杜仲、杜仲叶与杜仲雄花三者的化学组成可得到明显区分;初步筛选鉴定出23种差异显著的化学成分,且呈现不同的变化规律。杜仲、杜仲叶及杜仲雄花化学成分的差异及其变化规律,可为揭示三者药效差异的物质基础提供依据。 相似文献
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Antioxidants are emerging as prophylactic and therapeutic agents for various diseases. However, little is known about the antioxidant property of the extract from Flos Lonicerae, a medically useful traditional Chinese medicine herb. Here the antioxidant capacity of water, methanolic and 70% ethanolic extracts prepared from Flos Lonicerae to scavenge DPPH radical and reduce Fe3+ to Fe2+ is evaluated. Chlorogenic acid, a major component of Flos Lonicerae, is identified and further purified from 70% ethanolic extract with HPLC and its antioxidant capacity is also characterized. The content of total phenolic compounds and chlorogenic acid in Flos Lonicerae is determined. The present results demonstrate that all Flos Lonicerae extracts examined here exhibit antioxidant activity and chlorogenic acid is a major contributor to this activity, which implicates that the Flos Lonicerae extract may serve as potential source of natural antioxidants for treatment of some diseases. 相似文献
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A system of polar ordered resins was established for purification of chlorogenic acid in Flos Lonicerae. It was composed of three reversed phase resins, AB-8, DM-130 and NKA-9, representative for their gradually increased polarity and selectivity. A method of RP-HPLC was used for determination of chlorogenic acid. And the performance of adsorption and desorption for chlorogenic acid with the system of polar ordered resins was studied. Furthermore, the effects of concentration, pH and flow rate of the adsorbate on adsorption ability were researched. It is indicated that the optimum parameters for chlorogenic acid are as follows: pH 3.5 with a flow rate of 2.5 BV/h, the concentration of extract solution at 0.50, 0.40, 0.30 g/L respectively for the adsorptive operation twice, and 6.93, 8.66, 10.39 mol/L ethanol used as gradient eluants. The purity of resulted product of chlorogenic acid arrives 70.20% with yield of 89.79%. With simple procedures, low costs and high purity product, the method of system of polar ordered resins followed by sequential reversed phase separations can be used to refine the chlorogenic acid in the extraction of Flos Lonicerae. 相似文献
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Chu Chu Li Xia Li-Ping Bai Qin Li Ping Li Hu-Biao Chen Zhong-Zhen Zhao 《Microscopy research and technique》2009,72(6):454-463
Toxic and potent Chinese Materia Medica (T/PCMM) has become a hot and sensitive topic as more and more people around the world are interested in the safety of herbal medicines. T/PCMM is irreplaceable in treating some diseases; but it can easily cause serious problems if confused with other herbal medicines. Accurate identification is essential to ensure their safe use, but up to now, the literature on the authentication of T/PCMM is scant. Thus, we are undertaking a study of 31 T/PCMM originating from plants, animals, minerals, and secreta. Our previous study established microscopic observation as a simple, fast, accurate, and convenient method for identifying and authenticating animal and seed T/PCMM. This study focused on the authentication of flower T/PCMM as a part of the whole study. The flower T/PCMM studies were derived from two species, Datura metel L. (Flos Daturae) and Rhododendron molle G. Don (Flos Rhododendri Mollis). Other species easily confused with these two were also examined and characterized. Using the microscope camera, normal light and polarized light microscopy, we determined the macroscopic and microscopic features of the flowers; in addition, the oil immersion lens was used to study the pollen grain characteristics. The results demonstrated that flower T/PCMM can be identified and authenticated using a light microscope equipped with an oil immersion lens. This same equipment can be easily used to characterize other herbal flower medicines. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. 相似文献
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为了更准确地检测绿原酸的含量,对绿原酸含量分析的测定方法进行了综述。目前的检测方法主要有:紫外分光光度法、二阶导数光谱法、可见分光光度法、阻抑-催化褪色光度法、差示导数光谱法、二阶导数差示脉冲极谱定量分析法、胶束薄层色谱法、流动注射化学发光分析法、毛细管区带电泳法、薄层色谱扫描法(TLC法)、高效液相色谱法(HPLC法)、反相高效液相色谱法(RP-HPLC法)、系数倍率法、导数极谱法和HPLC法与其它方法的联用等,同时对绿原酸的检测方法进展进行了展望。 相似文献
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丁香抑菌成分超声波提取工艺研究 总被引:1,自引:0,他引:1
天然植物提取物对多种果蔬采后致腐菌有抑制作用,实验证明丁香提取物对葡萄采后低温主要致腐菌灰葡萄孢有明显的抑制作用.采用超声波法对丁香中抑菌成分进行提取.以生长速率法测定抑菌率,通过单因素和正交设计考察了溶剂种类、溶剂浓度、料液比、超声温度、超声时间和超声功率等因素对丁香提取物抑菌效果的影响.结果表明:采用80%乙醇作为提取溶剂,料液比为1:15、超声温度55℃、超声时间60min、超声功率 210W的提取条件下测得的抑菌率最高、效果最好. 相似文献