Three New Diarylpropanes from Dioscorea composita

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.     

The Crystalline Changes of Starch from Rhizoma Dioscorea by Acid Hydrolysis

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 …     

广山药中16种元素的分析比较

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。     

Chemical fingerprint analysis and quantitative determination of steroidal compounds from Dioscorea villosa,Dioscorea species and dietary supplements using UHPLC‐ELSD

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.     

Determination of Phenolic Acids and Flavones in Lonicera japonica Thumb. by Capillary Electrophoresis with Electrochemical Detection

Capillary electrophoresis with electrochemical detection (CE‐ED) was employed to analyze active ingredients of Lonicera japonica Thumb., an important crude herb frequently used in Chinese medicines. Hyperoside, chlorogenic acid, luteolin and caffeic acid are the major important active ingredients. Operating in a wall‐jet configuration, a 300 μm diameter carbon‐disk electrode was used as the working electrode, which exhibits a good response at +0.90 V (vs. saturated calomel electrode) for four analytes. Under the optimum conditions, the analytes were baseline separated within 20 min in a 50 mmol L^?1 borax buffer (pH 8.7). Notably, excellent linearity was obtained over two orders of magnitude with detection limits (S/N=3) ranging from 0.1 to 0.5 mg L^?1 for all the analytes. This method was successfully used in the analysis of Lonicera japonica Thumb. with relative simple extraction procedures, and the assay results were satisfactory.     

Complete (1)H and (13)C assignments of the four major saponins from Dioscorea villosa (wild yam)

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).     

紫山药组织RNA的提取方法

针对紫山药富含次生代谢物质的特点,探索出一种可有效去除其酚类、多糖和DNA等杂质的紫山药总RNA提取方法。在SDS法的基础上,于粉碎材料时,用水不溶性聚乙烯吡咯烷酮(PVP)防止酚类物质氧化,同时以高盐溶液去除多糖污染。利用这一方法提取的紫山药多个组织的总RNA,经琼脂糖电泳鉴定,可见清晰的18和28SRNA的2条带型,表明RNA完整,无弥散或降解;经过紫外吸收分析,A260/A380、A260/A2300分别在1.86~2.01,2.17~2.65,纯度良好,所提取的总RNA质量可以满足进一步分子生物学研究的要求。     

A New Furostanol Saponin from the Water-extract of Dioscorea nipponica Mak., the Raw Material of the Traditional Chinese Herbal Medicine Wei Ao Xin

26-O-β-D-Glucopyranosyl-furost-5(6),20(22)-dien-3β,26-diol 1, a new furostanol saponin, was isolated from the water-extract of Dioscorea nipponica Mak., the raw material of a traditional Chinese herbal medicine Wei Ao Xin. The structure of 1 was determined on the basis of its spectral data especially by NMR spectroscopy. The result provides the first example of naturally occurring furostanol saponins with a single saccharide chain at the C-26 position.     

A New Furostanol Saponin from Dioscorea futshauensis

A new furostanol saponin presenting moderate bioacitivity of inducting morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R.Kunth by bioacitivity-guided fractionation. The structure was established as 26-O-β-D-glucopyranosyl-3β,26-diol-23(S)-methoxyl-(25R)-furost-5,20(22)-diene-3-O-[α-L-rhamnopyranosyl(1→2)-β-D-glucopyranosyl(1→3)]-β-D-glucopyranoside on the basis of chemical evidencesand spectral analysis,especially by 2D-NMR techniques.     

Analysis of Dioscorea japonica by Hydrophilic Interaction Liquid Chromatography

Dioscorea japonica Thunb., traditionally used in folk medicine in Korea for the treatment of hyperglycemia, is known to have biological activity. However, few analytical methods suitable for rapid assessment of constituents of D. japonica rhizomes have been reported. A high-performance liquid chromatography method coupled with variable wavelength ultraviolet detection was developed for the determination of eight constituents of D. japonica rhizome. The separation was performed efficiently on a hydrophilic interaction liquid chromatography column by gradient elution with acetonitrile and water. Calibration curves showed excellent linear regression correlation levels (R ² > 0.9999) within the range of tested concentrations. Intra- and inter-day variations, evaluated by determining relative standard deviations, were below 1.71%. Constituent recovery rates were 93.37–104.24% with relative standard deviations of 0.55–1.98% for spiked D. japonica samples. The developed method was suitable for the qualitative and quantitative determination of the major components in D. japonica.