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1.
An ultra‐performance LC in combination with MS/MS method was established to evaluate the quality of Wu‐yao (the dried root of Lindera aggregata (Sims) Kosterm. (Lauraceae)) through simultaneous quantitation of five sesquiterpene lactones, linderagalactone D ( 1 ), linderagalactone C ( 2 ), hydroylindestenolide ( 3 ), neolinderalactone ( 4 ) and linderane ( 5 ). All compounds were separated on a Waters Acquity ultra‐performance LC HSS T3 column (2.1 mm×100 mm, 1.8 μm particle size) with linear gradient elution of acetonitrile and 0.1% formic acid. An ESI interface in the positive mode was employed prior to MS detection. All the compounds showed good linearity (R2≥0.9992). The recoveries, measured at three concentration levels, varied from 97.3 to 103.4% with RSDs <4.8%. The simple, rapid and reliable method was successfully applied to quantify the five components in 13 samples of Wu‐yao from different areas.  相似文献   
2.
Two new aryl‐tetralin lignan glycosides, linderanosides A and B ( 1 and 2 , resp.), and a new dihydrobenzofuran neolignan glycoside, linderanoside C ( 3 ), together with five known lignan derivatives ( 4 – 8 ) were isolated from the trunk of Lindera glauca. The structures of these new compounds were determined through spectroscopic analyses, including extensive 2D‐NMR data and acid hydrolysis. The absolute configurations of the compounds were clarified by circular dichroism (CD) spectroscopic studies. Compounds 1 – 8 were evaluated for their cytotoxicity against A549 (non‐small cell lung adenocarcinoma), SK‐OV‐3 (ovarian cancer cells), A498 (human kidney epithelial cells), and HCT‐15 (colon cancer cells) human tumor cell lines using sulforhodamine B assays in vitro.  相似文献   
3.
在KNO3底液下,用线性扫描阳极溶出伏安法同时测定了乌药样品中铜、铅、镉3种金属的含量.结果表明,在最佳实验条件下,铜、铅、镉的峰电位分别为0.067、-0.45和-0.64V(vs ScE);铜、铅、镉金属离子的质量浓度在0-0.8 mg·L-1范围内,呈现良好的线性关系,相关系数分别为0.991 3、0.990 5...  相似文献   
4.
In the present study, new sesquiterpene lactones (1) and (2) were isolated from the EtOAc soluble fraction of the water extract of Linderae Radix through bioassay-guided fractionation and isolation methods. The structure of these compounds was elucidated by spectroscopic analysis of their 2D NMR spectra, including COSY, HMBC, and HMQC techniques. Two isolates showed significant cytotoxicity against the human small cell lung cancer cell SBC-3, and lesser cytotoxicity against mouse fibroblast cell 3T3-L1.  相似文献   
5.
浙产山胡椒根挥发油化学成分的研究   总被引:1,自引:0,他引:1  
采用水蒸汽蒸馏法提取挥发油,气相色谱-质谱联用法结合计算机检索对浙产山胡椒根挥发油的化学成分进行分析和鉴定,用气相色谱面积归一法计算各组分的相对百分含量。从山胡椒根的挥发油中,分析并鉴定出17种化合物。主要含1,2,3,3a,4,5,6,7-八氢-1,4-二甲基-7-(1-甲基乙烯基)-奥艹、4,6,6-三甲基-2-(3-甲基-1,3-丁二烯基)-3-氧杂环-辛烷、愈创木醇、1,2,3,5,6,7,8,8a-八氢-1,4-二甲基-7-(1-甲基乙烯基)-奥艹,它们占挥发油总量的84.75%。  相似文献   
6.
乌药含有呋喃倍半萜、黄酮、生物碱、挥发油等多种化学成分,具有抗氧化、抗肿瘤及抑菌等活性.为研究乌药化学成分的性质,计算了乌药化学成分的分子连接性指数和电性拓扑状态指数,并筛选分子连接性指数中的0X,5X和5Xc,以及电性拓扑状态指数中的E1,E2和E3,将这6种结构指数作为神经网络的输入层变量,色谱保留时间作为输出层变量,做回归分析,采用6∶5∶1的神经网络结构,构建了预测能力较强的预测模型.该模型总相关系数rt为0.994 0,训练集相关系数为0.992 9,测试集相关系数为0.997 0,验证集相关系数为0.997 9,利用该模型计算得到的保留时间预测值与实验值吻合度较好,相对平均误差为2.66%.结果表明,乌药化学成分的色谱保留时间与6种结构参数之间具有良好的非线性关系.  相似文献   
7.
研究乌药根挥发油对肝癌HepG2细胞增殖和凋亡的影响。采用MTT法检测并比较乌药根挥发油对人肝癌HepG2细胞和正常肝细胞HL-7702增殖的影响;采用琼脂糖凝胶电泳及流式细胞仪法研究乌药根挥发油诱导HepG2细胞凋亡的作用。经不同浓度乌药根挥发油处理HepG2细胞24h,随药物浓度的增加,细胞生长抑制率逐渐增加。在低浓度范围(≤50μg·mL-1)时,乌药根挥发油对肝癌细胞的毒性作用要明显强于对正常细胞的作用。经过80和100μg·mL-1乌药根挥发油处理24h的HepG2细胞观察到典型的DNA ladder。经100、150和200μg·mL-1乌药根挥发油处理8h后,sub-G1期细胞的含量逐渐升高,分别是6.8%、12.6%和20.3%。提示乌药根挥发油能够有效抑制肝癌HepG2细胞的增殖,且具有一定的癌细胞选择性;同时能诱导HepG2细胞发生凋亡。更多还原  相似文献   
8.
Two New Compounds from Lindera chunii Merr.   总被引:1,自引:0,他引:1  
The root of Lindera chunii Merr. is a noble traditional Chinese medicine and frequently used as a substitute for L. aggregata to cure the chronic disease of rheumatoid arthritis1. In our previous paper, we have reported some components from the roots of L…  相似文献   
9.
A New Sesquiterpene from the Roots of Lindera strychnifolia   总被引:2,自引:0,他引:2  
The root of Lindera strychnifolia is used as a palliative and an antispasmodic in traditional chinese medicine. In previous studies of chemical constituents from this plant, more than 20 sesquiterpene lactones have been isolated and their structures were established1-7. In order to compare the difference of chemical constituents extracted by Supercritical Fluid Extraction (SFE) method and by organic solvent, the SFE extract from Lindera strychnifolia was investigated. A novel sesquiterp…  相似文献   
10.
高速逆流色谱法分离制备乌药叶中的黄酮类成分   总被引:3,自引:0,他引:3  
刘云  侴桂新 《色谱》2007,25(5):735-739
应用高速逆流色谱法分离制备了乌药叶中的黄酮类成分。以正己烷-乙酸乙酯-正丁醇-冰醋酸-水(体积比为2∶4∶2∶1.5∶6)为两相溶剂系统,在主机转速800 r/min、流速2.0 mL/min、检测波长280 nm条件下进行分离制备。所得流分经高效液相色谱法检测,并经电喷雾电离质谱、核磁共振氢谱、碳谱鉴定化合物的结构。结果表明,从乌药叶总黄酮粗提物中分离得到了5个化合物,分别为槲皮素-3-O-β-D-葡萄糖苷(1)、槲皮素-5-O-β-D-葡萄糖苷(2)、槲皮素-3-O-β-D-呋喃阿拉伯糖苷(3)、槲皮素-3-O-吡喃鼠李糖苷(4)、山奈酚-7-O-α-L-吡喃鼠李糖苷(5),其中化合物1,2,3和5 为首次从该植物中分离得到。该法具有简便、快速的优点。  相似文献   
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