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1.
Three New Diarylpropanes from Dioscorea composita   总被引:1,自引:0,他引:1  
Three new diarylpropanes were isolated from the dried rhizomes of Dioscorea composita Hemsl., and their structures were determined as 1, 3-bis-(2-hydroxy-4-methoxyphenyl) propane (1), 1, 3-bis-(2, 4-dihydroxyphenyl)propane (2), 1-(2′-hydroxy-4′-O-β-D- glucopymnosy-phenyl)-3-(2“, 4“-dihydroxyphenyl)propane (3), by spectroscopic analysis, respectively.  相似文献   
2.
Dioscoreae (Chinese name Shanyao), the rhizome of various species of genus Dioscorea opposita Thunb.(Dioscoreaceae), has been used as an important invigorant in traditional Chinese medicine (TCM) for many years1. Starch, the most abundant carbohydrate in …  相似文献   
3.
广山药中16种元素的分析比较   总被引:21,自引:1,他引:21  
用原子吸收法和分光光度法测定了5个产地的广山药及怀山药中16种元素的含量,并进行了比较。发现广山药及怀山药中均含有Mn,Fe,Zn,Ca,Cu,Mg,P,Se等元素,5个产地的广山药中的Cu/Zn值均低于正常人血清的Cu/Zn,这些元素可能是怀山药,广山药具有补脾养胃,生津益肺,补肾涩精,治疗糖尿病等功效的物质基础之一;广山药长期作为山药的一个品种同等入药,食用是有科学根据的;广山药,怀山药中含有一定量的As,Hg。  相似文献   
4.
盾叶薯蓣种子萌发条件及诱导外植体愈伤的研究   总被引:3,自引:0,他引:3  
作者研究了盾叶薯蓣种子在MS培养基中的萌发条件,并且对其茎、叶片、叶柄进行愈伤组织的诱导.结果表明:(1)在25℃下,用无菌水浸泡的种子在MS 6mg/L赤霉素上获得最高的萌发率;(2)MS 2,4-D 4mg/L为较理想的愈伤组织诱导培养基,在此培养基上,茎、叶片、叶柄的诱导率分别是:100%、40%、20%.  相似文献   
5.
穿龙薯蓣高产栽培技术研究   总被引:1,自引:0,他引:1  
主要通过穿龙薯蓣(Dioscoreanipponica)的栽植密度试验及栽植深度试验,用方差分析及多重比较的方法来寻找穿龙薯蓣高产栽培技术。经过试验分析,最佳栽植密度为20cm×50cm,最适栽植深度为5cm~10cm。  相似文献   
6.
Ultra high‐performance liquid chromatography (UHPLC) with evaporative light scattering detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC? system with an UPLC? BEH Shield RP18 column using a gradient elution with water and acetonitrile. Owing to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The 12 compounds could be separated within 15 min using the developed UHPLC method with detection limits of 5–12 µg/mL with 2 μL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection and limits of quantification. The relative standard deviations for intra‐ and inter‐day experiments were <3.1%, and the recovery efficiency was 97–101%. The total content of standard compounds was found to be in the ranges 0.01–14.5% and 0.9–28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC–mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
7.
光质对怀山药微型块茎诱导形成的影响   总被引:2,自引:0,他引:2  
在不加活性碳的情况下,无论是固体培养或是液体培养在各光质下均不利于微型块茎的诱导.而在加入活性碳的固体培养基上,各光质均有利于微型块茎的诱导;尤以红光和白光下最好,诱导率达到100%,微型块茎的体积和可溶性糖含量也达到了最大.  相似文献   
8.
穿山龙中薯蓣皂甙元的测定与宁夏药物资源的开发   总被引:3,自引:0,他引:3  
首次用高效液相色谱法分析测定了穿山龙中的薯蓣皂甙元,建立了该中药中薯蓣皂甙元分离,测定的色谱方法,利用本文考察了宁夏野生穿山龙,为宁夏药物资源的开发提供了科学依据。  相似文献   
9.
穿山龙多糖分离纯化工艺的研究   总被引:1,自引:0,他引:1  
以粗多糖得率为指标,比较水醇法、水提ZTC吸附澄清剂法和超声波法三种提取方法,并以穿山龙多糖含量为指标,考察采用水醇法提取穿山龙多糖时,回流时间、固液体积比,提取次数对多糖含量的影响;同时,用硫酸-苯酚法对穿山龙粗多糖中的多糖含量进行了测定.实验结果表明,水醇法提取的多糖得率高于水提ZTC吸附澄清剂法和超声波法,分别提高6.0倍和6.6倍.水醇法的最佳提取工艺条件:回流提取时间90min,液料比1:10,提取次数3次.  相似文献   
10.
Complete (1)H and (13)C spectral assignments for the four major steroidal saponins isolated by methanolic extraction of the roots of Dioscorea villosa, collected in North Carolina, United States (in summer and autumn), are presented in this paper. The structures were determined by a combination of (1)H, (13)C and 2D NMR techniques and were found to be ((3beta,25R)-26-(beta-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl-O-beta-D-glucopyranosyl-(1 --> 3)-O-beta-D-glucopyranosyl-(1 --> 4)-O-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (1) (or methyl parvifloside), ((3beta,25R)-26-(beta-D-glucopyranosyloxy)-22 methoxyfurost-5-en-3-yl-O-alpha-L-rhamnopyranosyl-(1 --> 2)-O-[beta-D-gluco- pyranosyl-(1 --> 4)]-beta-D-glucopyranoside (2) (or methyl protodeltonin), (3beta,25R)-spirost-5-en-3-yl-O-beta-D-glucopy ranosyl-(1 --> 3)-O-beta-D-glucopyranosyl-(1 --> 4)-O-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranoside (3) (or Zingiberensis saponin I) and (3beta,25R)-spirost-5-en-3-yl-O-alpha-L-rhamnopyranosyl-(1 --> 2)-O-[beta-Ds-glucopyranosyl -(1 --> 4)]-beta-D-glucopyranoside (4) (or deltonin).  相似文献   
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