中草药龙胆中微量元素的形态分析

采用传统煎煮法对丽水当地中草药龙胆中钙、锌、铁、铜、锰、铅、镉和铬等8种元素进行提取,并用微孔滤膜分离提取液中可溶态与悬浮态;利用大孔吸附树脂分离可溶态中有机态与无机态;采用正辛醇/水分配体系模拟水煎液中这8种微量元素在人体胃肠中分配情况,再用火焰原子吸收光谱法(FAAS)测定了各种形态中的8种元素。研究结果显示:龙胆中8种元素的提取率在34.25%～74.53%,浸留比在49.58%～371.1%,悬浮态颗粒吸附率在6.5%～29.8%,该法对各元素的加标回收率在91.3%～108.5%;相对标准偏差小于3.5%;锌、铁、铜、锰在正辛醇/水分配体系中溶出性受酸碱性影响大些。     

Triterpenoids and Iridoid Glycosides from Gentiana dahurica

One new and six known pentacyclic triterpenoids, 1 and 4 – 9 , resp., along with two new and three known iridoid glycosides, 2 and 3 , and 10 – 12 , resp., were isolated from the roots of Gentiana dahurica (‘Qin‐Jiao’). The new structures were elucidated by means of spectroscopic and chemical methods as 1β,2α,3α,24‐tetrahydroxyursa‐12,20(30)‐dien‐28‐oic acid ( 1 ), 6′‐O‐acetylgentiopicroside ( 2 ), and 3′‐acetylgentiopicroside ( 3 ). Isolated compounds were tested for their cytotoxicity against the MCF‐7 human breast cancer cell line using the MTT assay. Among them, triterpenoids 2α,3β,24‐trihydroxyurs‐12‐en‐28‐oic acid ( 6 ) and 3β,24‐dihydroxyurs‐12‐en‐28‐oic acid ( 9 ) were found to have moderate cytotoxic effects with IC₅₀ values of 20.9 and 21.7 μg/ml, respectively. Additionally, the chemotaxonomic significance of the identified secondary metabolites is briefly discussed.     

微波消解-火焰原子吸收光谱法测定秦艽和麻花秦艽中多种微量元素

密封微波消解已被运用于火焰原子吸收光谱法对中草药中微量元素含量的测定过程中。微波消解法具有方便省力,安全快捷,污染少,样品溶解完全等特点。选用硝酸和双氧水（5∶1）的混合消化液作为消解剂进行微波消解。运用火焰原子吸收光谱法测定了秦艽和麻花秦艽中的Fe,Mn,Ni,Cu,Zn,Ca,Mg,Cr等八种微量元素的含量。进行了微波消解条件的选择及消化结果精密度实验,该方法的加标回收率为88.1%～114.5%,相对标准偏差（RSD）<3.12%,具有较为良好的准确度和精密度。结果表明,秦艽和麻花秦艽均富含Ca,Mg,Fe,Mn,Zn等元素,而Ni和Cr含量均较低。通过对秦艽和麻花秦艽微量元素含量的比较,发现秦艽中的Mg, Fe, Mn, Ni含量较高,而麻花秦艽中的Zn, Cu, Ca, Cr含量较高。此结果为探讨微量元素与秦艽和麻花秦艽的药效关系提供了一定的科学数据。并且,通过本实验为秦艽和麻花秦艽的进一步研究和综合开发利用提供了新的科学依据。     

Investigation of chemical diversity in different parts and origins of ethnomedicine Gentiana rigescens Franch using targeted metabolite profiling and multivariate statistical analysis

Gentiana rigescens, an ethnomedicine, is widely cultivated in Yunnan province of China. Although a wide range of metabolites including iridoid glycosides, flavonoids and triterpenoids have been reported in this ethnomedicine, the data on accumulation and distribution of metabolites in certain parts are limited. In this study, targeted metabolic fingerprinting of iridoid glycosides based on liquid chromatography–ultraviolet detection–tandem mass spectrometry (LC‐UV‐MS/MS) was developed to investigate the metabolic similarities and differences in different parts and origins. Thirty‐one compounds, including iridoid glycosides and flavonoids, were detected from targeted metabolite profiling and plausibly assigned to the different parts of G. rigescens. Multivariate statistical analysis was designed to reveal close chemical similarities between all the selected samples and to identify key metabolites characteristic of the standard. The results suggested that accumulation and distribution of metabolites in aerial and underground parts were different. Moreover, root samples tended to be grouped on the basis of the geographical closeness of region. Five metabolites can be considered as potential markers for the classification of underground parts from different regions. These results provided chemical information on the potential pharmaceutical value for further research, making G. rigescens ideal for the rational usage of different parts and exploitation of the source. Copyright © 2015 John Wiley & Sons, Ltd.     

Rapid preparative separation of six bioactive compounds from Gentiana crassicaulis Duthie ex Burk. using microwave‐assisted extraction coupled with high‐speed counter‐current chromatography

A rapid method combining microwave‐assisted extraction (MAE) and high‐speed counter‐current chromatography (HSCCC) was applied for preparative separation of six bioactive compounds including loganic acid ( I ), isoorientin‐4′‐O‐glucoside ( II ), 6′‐O‐β‐d ‐glucopyranosyl gentiopicroside ( III ), swertiamarin ( IV ), gentiopicroside ( V ), sweroside ( VI ) from traditional Tibetan medicine Gentiana crassicaulis Duthie ex Burk. MAE parameters were predicted by central composite design response surface methodology. That is, 5.0 g dried roots of G. crassicaulis were extracted with 50 mL 57.5% aqueous ethanol under 630 W for 3.39 min. The extract (gentian total glycosides) was separated by HSCCC with n‐butanol/ethyl acetate/methanol/1% acetic acid water (7.5:0.5:0.5:3.5, v/v/v/v) using upper phase mobile in tail‐to‐head elution mode. 16.3, 8.8, 12., 25.1, 40.7, and 21.8 mg of compounds I–VI were obtained with high purities in one run from 500 mg of original sample. The purities and identities of separated components were confirmed using HPLC with photo diode array detection and quadrupole TOF‐MS and NMR spectroscopy. The study reveals that response surface methodology is convenient and highly predictive for optimizing extraction process, MAE coupled with HSCCC could be an expeditious method for extraction and separation of phytochemicals from ethnomedicine.     

傅里叶红外光谱对野生及栽培滇龙胆不同部位的研究

中药及其制剂的应用具有悠久历史,随着研究的深入,市场需求量日益增加,野生资源难以满足市场需求,开展野生和栽培品及化学成分累积动态的研究具有重要意义。为了比较野生和栽培的滇龙胆不同部位(根、茎、叶)化学成分的差异,用傅里叶红外光谱、二阶导数光谱对其进行分析及评价研究。采集60份样品的红外光谱数据,用Nicolet Omnic8.0软件计算各个样品的二阶导数光谱和匹配值。结果显示,野生和栽培滇龙胆根、茎及叶的红外光谱图整体峰形相似,在1 732,1 643,1 613,1 510,1 417,1 366,1 322,1 070cm-1附近主要为酯类、萜类、糖类物质的吸收峰。1 800~600cm-1波段范围内,样品与龙胆苦苷标准品二阶导数光谱的峰位和峰强有差异,具有多个指纹特征峰,分别为1 679,1 613,1 466,1 272,1 204,1 103,1 074,985,935cm-1;野生和栽培样品的根在1 613cm-1(龙胆苦苷中萜类物质C—C吸收峰)附近特征峰明显强于茎和叶,根中龙胆苦苷类成分高于茎及叶;野生样品的茎在1 521,1 462,1 452cm-1附近为木质素类物质的苯环骨架振动峰,并呈现强吸收峰,栽培样品茎呈现中等强峰,茎富含木质素类物质。所有样品红外光谱与野生样品根的平均光谱相似度较大,二阶导数光谱与野生样品根的平均光谱的相关性差异较大,相似度大小分别为:根茎叶。红外光谱法结合二阶导数谱能为同类物种野生和栽培药材不同部位的差异分析和评价提供参考。     

New Iridoid and Secoiridoid Glucosides from the Roots of Gentiana manshurica

One new iridoid glucoside, 4″‐O‐β‐D ‐glucosyl‐6′‐O‐(4‐O‐β‐D ‐glucosylcaffeoyl)linearoside ( 1 ), and two new secoiridoid glucosides, 6′‐O‐acetylsweroside ( 2 ) and 6′‐O‐acetyl‐3′‐O‐[3‐(β‐D ‐glucopyranosyloxy)‐2‐hydroxybenzoyl]sweroside ( 3 ), were isolated from the dried roots of Gentiana manshurica (Gentianaceae), together with 11 known ones, including one iridoid glucoside, five secoiridoid glucosides, and five triterpenes. The structures of the new compounds were determined on the basis of detailed spectroscopic analyses and acidic hydrolysis.     

Minor antifungal aromatic glycosides from the roots of Gentiana rigescens （Gentianaceae）

Two new phenolic glycosides,2,3-dihydroxybenzoic acid methyl ester 3-O-β-D-glucopyranosyl-(1-6)-β-D-glucopyranoside(1) and 2,5-dihydroxylbenzofuran 5-O-β-D-xylopyranosyl-(1-6)-O-β-D-glucopyranoside(2),were isolated as the minor chemical constituents from the roots of Gentiana rigescens,along with 15 known compounds.Their structures were elucidated by detailed spectroscopic analysis,including 1D,2D NMR and chemical method.All of these compounds were isolated for the first time from the title plant.Moreove...     

微波消解-FAAS测定秦艽中8种微量元素的含量

利用微波消解-火焰原子吸收光谱法测定秦艽药材中8种微量元素钙、铜、铁、锰、锌、镁、铅、镉的含量。秦艽药材中含有较丰富的镁、钙、铁。该方法灵敏度高、快速、准确,所测数据可为秦艽药材的合理利用提供可靠依据。     

Simultaneous determination of six index constituents and comparative analysis of four ethnomedicines from genus Gentiana using a UPLC‐UV‐MS method

Many species from genus Gentiana (Gentianaceae) have a long history of applications as folk medicines in the world. A simple rapid UPLC‐UV‐MS/MS method has been developed and validated for the simultaneous determination of six index constituents (gentiopicroside, swertiamarin, loganic acid, sweroside, mangiferin and ferulic acid) from the four ethnomedicines (G. rigescens Franch. ex Hemsl., G. rhodantha Franch. ex Hemsl., G. scabra Bunge and G. farreri Balf. f.). The UPLC analysis was performed on Shim‐Pack XR‐ODS III (150 × 2.0 mm, 2.2 µm). The mobile phase was consisted of acetonitrile–0.1% formic acid water using gradient elution. The wavelength 242 nm was chose for the four iridoids as well as mangiferin and 320 nm was set for ferulic acid. Mass spectrometry was applied for identification and quantification for analytes with low concentration. All the regression equations revealed a good linear relationship (R² > 0.9993). Accuracy and precision were all within the required limits. The chromatogram fingerprints analysis combined with principal component analysis showed the similarity values of the four species were <0.788 while the similarity values of G. scabra Bunge and G. rigescens Franch. ex Hemsl. were >0.993, which provided reasonable foundation for utilization and clinical application of the four ethnomedicines. This developed method appears to be a useful tool for quality control of the four ethnomedicines. Copyright © 2014 John Wiley & Sons, Ltd.