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41.
High‐speed countercurrent chromatography is a liquid–liquid separation chromatographic technique, which has the unique feature of eliminating irreversible adsorption using liquid support medium, and is widely used in research and development of traditional Chinese medicine, biochemistry, food, environment analysis, and so on. In this review, some new developments of countercurrent chromatography, for instance cross‐axis countercurrent chromatography, dual countercurrent chromatography, foam countercurrent chromatography, and pH‐zone‐refining countercurrent chromatography are presented. Furthermore, the research and progress in high‐speed countercurrent chromatography techniques and its application in the separation and purification of terpenoids and saponins are reviewed.  相似文献   
42.
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   
43.
Eighteen different triterpene saponins isolated from Polygala tenuifolia were investigated by electrospray ionization ion trap multiple-stage mass spectrometry (ESI-ITMS(n)) in positive and negative ion modes. MS(1)-MS(3)/MS(4) spectra of the both modes were analyzed, and they all gave fragments in line and shared common fragmentation patterns. Key fragments from MS(n) spectra of both the modes and their proposed fragmentation pathways were constructed with examples illustrated for the formation of characteristic fragments in the saponins. Two special fragmentation patterns were proposed: (1) the formation of fragments by cleavage of CH(2)O from Delta(12)-14alpha-CH(2)OH of the oleanene-type saponin aglycone in both positive and negative MS(n) (n > or = 2) modes; (2) the occurrence of fragments by cleavage of CO(2) and 3-glucose as the characteristic structure feature of 23-COOH at the oleanene-type saponin aglycones coupled with 3-Glc substitutes in the negative MS(n) (n > or = 2) modes. Peak intensities in MS(n) spectra were also correlated with structural features and fragmentation preferences of the investigated saponins, which are discussed in detail. In general, fragments formed predominantly by cleavages of glycosidic bonds in the positive mode, while selective cleavages of acyl bonds preceded that of glycosidic bonds in negative MS(n) (n > or = 2) mode, both of which could well be applied to the structural analysis of these saponins. Interpretation of MS(n) spectra presented here provided diagnostic key fragment ions important for the structural elucidation of saponins in P.tenuifolia.  相似文献   
44.
45.
Malonyl‐triterpene saponins (MTSs) attract scientific attentions because of their structural diversities and valuable bioactivities. However, its thermal instability brings a huge amount of challenges for isolation and purification of this class of compounds. To our best knowledge, there has been no report on isolation and analysis of MTSs from genus Caulophyllum. In this study, a strategy combining data acquisition using an energy‐resolved technique and the narrow widow extracted ion chromatograms as data mining method was developed for discovery and identification of MTSs in Caulophyllum robustum hair roots by ultra high liquid chromatography coupled to electrospray ionization Fourier transform mass spectrometry. The method was performed at an independent MS full scan using our bottom‐up energies by in‐source collision induced dissociations with 0, 25, 50 and 100 eV in both positive and negative modes. Precursor ion as well as fragment ion information was simultaneously collected from four energy‐resolved MS spectra in a single run of 18 min. The fragmentation pathways of intact deprotonated, protonated and sodium ions of MTSs were proposed for the structural elucidation of Caulophyllum MTSs. A flowchart involving a stepwise procedure based on key fragments from ESI?/ESI+‐FT‐MS(1, 1) to MS(1, 4) spectra was constructed for the identification of structural elements in the MTSs. As a result, a total of 23 MTSs were discovered and tentatively identified, which had not been reported from Caulophyllum species before. All of these were potentially new compounds. This study provides an excellent example for discovery and identification of MTSs in herb medicines. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
46.
Yucca schidigera Roezl. (yucca) is one of the major industrial sources of steroid saponins approved by the Food and Drug Administration (FDA) as generally recognized as safe. Due to the increasing applications of yucca extracts, there is a need for a simple, low-cost method for the authentication of samples. This paper presents a method to obtain unique fingerprints of commercial products of yucca using a single-thin layer chromatography (TLC) system and two visualization reagents for the detection of phenolics and saponins, as a tool for the preliminary quality assessment of the products.  相似文献   
47.
Ultrasound-assisted extraction was evaluated as a simpler and more effective alternative to conventional extraction methods for the isolation of ginsenosides (saponins) from various types of ginseng. The ginseng samples were extracted with different solvents, under either direct sonication by an ultrasound probe horn or indirect sonication in an ultrasound cleaning bath. The ultrasonic extraction was compared with the conventional method of refluxing boiling solvents in a soxhlet extractor, on the yields of both the total saponin isolated by thin-layer chromatography and the individual ginsenosides by high performance liquid chromatography. It was found that the sonication-assisted extraction of ginseng saponins was about three times faster than the traditional extraction method. The ultrasonic extraction was not only more efficient but also convenient for the recovery and purification of the active ingredients of plant materials. In addition, the sonication-assisted extraction can be carried out at lower temperatures which are favorable for the thermally unstable compounds.  相似文献   
48.
仙茅根茎中的配糖体   总被引:1,自引:0,他引:1  
仙茅o以社OrchiodesGaertn)为石蒜科植物仙茅的根茎,具温肾阳,壮筋骨,治阳萎精冷,小便失禁,崩漏,心腹冷痫,腰脚冷痹,痈且,瘦瘦之功效l’]。久保道德[21分离获得的仙茅威(Cureul-gOSid经药理实验证明能大幅度促进巨噬细胞的增生能力和吞噬作用,提高人体免疫功能。在云南省陇川县采集仙茅的根25309,经*eOH热提取后,硅胶柱层析,*HC卜Me规梯度洗脱,反相【卜18柱层析,MeOH爿p洗脱纯化。得到7个化合物(-G)。化合物A为首次从该植物中分离获得。F为一个新三荫眈本文…  相似文献   
49.
两个非对映异构三萜皂甙的结构鉴定   总被引:7,自引:0,他引:7  
从合欢皮95%乙醇提取物中分得2个新三糖链九糖皂甙(1,2),经化学方法和光谱分析,将其结构分别鉴定为:3-O-[β-D-吡喃木糖基-(1→2)-β-D-吡喃阿拉伯糖基-(1→6)-β-D-葡萄糖基]-21-O-(6S)-2-反式-2,6-二甲基-6-O-[4-O-((6R)-2-反式-2,6-二甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基)-β-D-吡喃鸡纳糖基]-2,7-辛二烯酸基金合欢酸28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖基酯(1)和3-O-[β-D-吡喃阿拉伯糖基-(1→2)-β-D-吡喃呋糖基-(1→6)-β-D-葡萄糖基]-21-O-(6S)-2-反式-2,6-二甲基-6-O-[4-O-((6S)-2-反式-2,6-二甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基)-β-D-吡喃鸡纳糖基]-2,7-辛二烯酸基金合欢酸28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖基酯(2),分别命名为合欢皂甙J14(JulibrosideJ14)和合欢皂甙J15(JulibrosideJ15)  相似文献   
50.
人参皂甙-Rh2(ginsenoside Rh2)和Rg3是从人参中分离得到的具有抗癌活性的四环三萜类原人参二醇型低糖链皂甙单体。其中,以人参皂甙为主要成分的抗癌新药Rg3参—胶囊已获国家药品监督管理局颁发的中药一类新药证书。皂甙类成分要从植物中分离困难。为了得到某些活性  相似文献   
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