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11.
杉木针叶磷脂酰甘油脂肪酸组成分析   总被引:1,自引:0,他引:1  
用改进的DEAE阴离子交换柱色谱法和硅胶薄层色谱法分离制备杉木针叶磷脂酸甘油,用气相色谱法测定了它的脂肪酸组成。分析结果表明,抗寒性强的杉木品种的针叶磷脂酰甘油脂肪酸的(18:1+18:2+18:3)/[16:0+16:1(3t)]比值比不抗寒品种的高。  相似文献   
12.
A rapid, sensitive and reproducible micellar electrokinetic chromatographic method using hexamethyldisilazane as on-line regenerating covalent coating was developed for the quantification of ephedrine (E) and pseudoephedrine (PE). E and PE were derivatized with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazol for laser-induced fluorescence detection. The on-line regenerating covalent coating formed a combinative double coating with the subsequently produced dynamic SDS coating. The total coating can be easily removed and conveniently regenerated on-line. The simple coating procedure was described. By a series of optimization, a running buffer of 20 mm Na(2)B(4)O(7) + 16 mm SDS was applied for the separation of the derivatives. Linear relationships for E and PE were obtained in the range of 0.044-6.60 microg mL(-1) (correlation coefficients: 0.9975 for E, 0.9981 for PE), and the detection limits for E and PE were 1.71 and 0.67 ng mL(-1), respectively. The separation speed, the reproducibility and the sensitivity were much improved over those of other capillary electrophoresis methods more recently reported. The method was applied to the analysis of the two alkaloids in traditional herbal preparations with recoveries in the range 92.8-104.8%.  相似文献   
13.
碘酸钾存在下极谱催化波法测定陈皮甙   总被引:2,自引:0,他引:2  
过玮  何盈盈  许昭  宋俊峰 《分析化学》2002,30(2):202-203
基于陈皮甙在KIO3存在下产生的极谱催化波,拟定了测定陈皮甙的新方法。在 0.55 mol/L HAc-0.01mol/L NaAc(pH 4.00±0.05)-1.0×10~(-3)mol/L KIO3缓冲溶液中,陈皮甙催化波的峰电位为-1.35 V(vs,SCE),它的一阶导数峰峰电流与陈皮甙浓度在2.6 × 10~(-7)~2.6 × 10~(-6)mol/L范围内呈线性关系(r=0.9970,n=6)。本方法比现有的电化学方法灵敏度高一个数量级。可用于直接测定中草药贯众水提液中陈皮甙含量。  相似文献   
14.
A capillary electrophoretic assay for determining aloe-emodin (AE), methyl p-coumarate (MC), and 3,4-dihydro-6,8-dihydroxyl-[(3s)-2'-acetyl-3'-hydroxyl-5'-methoxy-benzyl]-isocoumarin (DDI) in Aloe vera has been developed. Baseline separation was achieved within 15 min using a running buffer of 20 mm borax containing 10% (v/v) acetonitrile at pH 10.5. A linear relationship between the peak area and the concentration of the analytes was found in the ranges 5-500, 10-1000 and 2-1000 micro g/mL for AE, MC and DDI, respectively, with correlation coefficients of 0.9992-0.9998. The relative standard deviations of migration time and peak area were within 0.17-0.19 and 1.52-3.37%, respectively. The recoveries of AE, MC and DDI were 105, 102 and 96.4%. The contents of AE, MC and DDI in Aloe vera were measured to be 5.13, 0.768 and 1.30 mg/g, respectively.  相似文献   
15.
Since ancient times, various herbs have been used in Asia, including Korea, China, and Japan, for wound healing and antiaging of the skin. In this study, we manufactured and chemically analyzed a novel distillate obtained from a fermented mixture of nine anti-inflammatory herbs (Angelica gigas, Lonicera japonica, Dictamnus dasycarpus Turcz., D. opposita Thunb., Ulmus davidiana var. japonica, Hordeum vulgare var. hexastichon Aschers., Xanthium strumarium L., Cnidium officinale, and Houttuynia cordata Thunb.). The fermentation of natural plants possesses beneficial effects in living systems. These activities are attributed to the chemical conversion of the parent plants to functional constituents which show more potent biological activities. In our current study, the distillate has been manufactured after fermenting the nine oriental medical plants with Lactobacillus fermentum, followed by distilling. We analyzed the chemical ingredients involved in the distillate and evaluated the effects of topical application of the distillate on ultraviolet B (UVB)-induced skin damage in Institute of Cancer Research (ICR) mice. Topical application of the distillate significantly ameliorated the macroscopic and microscopic morphology of the dorsal skin against photodamage induced by UVB radiation. Additionally, our current results showed that topical application of the distillate alleviated collagen disruption and reduced levels of proinflammatory cytokines (tumor necrosis factor alpha and interleukin 1 β expressions) in the dorsal skin against UVB radiation. Taken together, our current findings suggest that the distillate has a potential to be used as a material to develop a photoprotective adjuvant.  相似文献   
16.
中药质量控制的研究策略和色谱技术   总被引:8,自引:1,他引:8  
李发美  熊志立  鹿秀梅  秦峰  李小芩 《色谱》2006,24(6):537-544
综述了色谱技术作为现代高效分离分析技术在中药药效物质基础研究和中药质量控制中的重要作用。提出中药药效物质组学研究策略,以实现中药药效物质基础与作用机理研究的一体化,进而从深层次揭示和全面控制中药的内在质量。论述结果表明,现代色谱及其联用技术是中药质量研究的重要技术平台之一。  相似文献   
17.
建立了同时分离药用大黄提取液中大黄酸、芦荟大黄素、大黄素、大黄酚和大黄素甲醚5种蒽醌类活性成分的梯度加压毛细管电色谱的新方法.实验结果显示,大黄提取液中的5种蒽醌化合物可在22min内完全分离,梯度洗脱微柱液相色谱的柱效为等度洗脱微柱液相色谱的6.63倍,梯度毛细管电色谱的柱效为梯度微柱液相色谱的4.6倍.  相似文献   
18.
宋凤瑞  闫存玉  刘宁  刘志强  刘淑莹 《分析化学》2005,33(12):1743-1746
选择与SAPS病毒相关的DNA片段作为抗病毒药物筛选的靶分子,利用生物质谱技术,通过对该寡聚去氧核苷酸分子与常见中药黄芪、穿心莲、刺五加、苦杏仁、牛蒡子、栀子、菘蓝(板蓝根、大青叶)及厚朴中的主要化学成分——黄芪甲苷、苦杏仁苷、穿心莲内酯、栀子苷、紫丁香苷、牛蒡子苷、靛蓝、靛玉红、厚朴酚及和厚朴酚的相互作用研究,发现与寡聚去氧核苷酸的作用强度顺序为:黄芪甲苷>苦杏仁苷>穿心莲内酯>栀子苷>紫丁香苷>牛蒡子苷、靛玉红、靛蓝、厚扑酚及和厚朴酚与寡聚去氧核苷酸没有复合物形成。还研究了黄芪甲苷与3种脱氧核苷的相互作用。本方法作为药物筛选具有一定的可行性。  相似文献   
19.
中草药中微量元素形态分析方法研究   总被引:29,自引:0,他引:29  
  相似文献   
20.
白酒中游离有机酸的定量测定   总被引:4,自引:2,他引:4  
胡国栋  程劲松  朱叶 《色谱》1994,12(4):265-267
本文介绍了一种简单、准确测定白酒中游离有机酸的方法。酒样经中和、浓缩后,未经衍生直接注入毛细管色谱柱,经气相色谱-质谱鉴定并采用三种内标物定量,可准确测定白酒中C2~C18的二十种游离脂肪酸及三种苯羧酸,结果重现性良好。  相似文献   
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