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151.
Myschik J Lendemans DG McBurney WT Demana PH Hook S Rades T 《Micron (Oxford, England : 1993)》2006,37(8):724-734
ISCOM matrices constitute colloidal structures formed from Quillaja saponins, cholesterol and phospholipid. Addition of protein antigens to these matrices leads to the formation of ISCOMs. In this review we report on microscopic investigations of ISCOM matrices and ISCOMs as well as related colloidal structures, such as helices, worm-like micelles, ring-like micelles, and lamellae structures. We briefly outline the immunologic basis for the use of ISCOMs as vaccine delivery systems, and describe the various methods to form ISCOMs. Negative staining transmission electron micrographs of all colloidal structures are presented and described. On the basis of our microscopic investigations, different formation mechanisms of ISCOMS are discussed. 相似文献
152.
Zou P Fu J Yu HS Zhang J Kang LP Ma BP Yan XZ 《Magnetic resonance in chemistry : MRC》2006,44(12):1090-1095
The detailed NMR studies and full assignments of the 1H and 13C spectral data for two new furostanol saponins isolated from Agave sisalana leaves are described. Their structures were established using a combination of 1D and 2D NMR techniques including 1H, 13C, 1H-1H COSY, TOCSY, HSQC, HMBC and HSQC-TOCSY, and also FAB-MS spectrometry and chemical methods. The structures were established as (25S)-26-(beta-D-glucopyranosyl)-22 xi-hydroxyfurost-12-one-3beta-yl-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3)-O-[O-beta-D-glucopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl-(1-->4)-beta-D-galacto- pyranoside (1) and (25S)-26-(beta-D-glucopyranosyl)-22xi-hydroxyfurost-5-en-12-one-3beta-yl-O-alpha-L-rhamno- pyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3)-O-[O-beta-D-glucopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl- (1-->4)-beta-D-galactopyranoside (2). 相似文献
153.
Using high-resolution quadrupole time-of-flight mass spectrometry along with an electrospray ionization source (ESI-QqTOF-MS), accurate molecular weights of 13 steroid saponins extracted from the rhizomes of Dioscorea panthaica were acquired and the corresponding molecular formulae obtained. In order to elucidate the fragmentation pathways of steroid saponins in D. panthaica, 10 authentic samples were investigated using ESI-QqTOF-MS/MS. In addition, atmospheric pressure chemical ionization mass spectrometry combined with ion trap tandem mass spectrometry (APCI-IT-MS/MS) was used to analyze the structures of 13 steroid saponins in D. panthaica. Through the analysis of their tandem mass data, diagnostic fragment ions of the spirostanol and furostanol steroid saponins in D. panthaica were detected as m/z 271.2056 and 253.1951. In addition, four pairs of isomers were detected and the possible structures of four unknown steroid saponins in D. panthaica speculated. ESI-TOF and APCI-MS(n) have proved to be effective tools for research on fragmentation mechanism of steroid saponins and the rapid determination of native steroid saponins in extract mixture, thereby avoiding tedious derivation and separation steps. 相似文献
154.
Qingchao Liu Lei Zhang Xiangpeng Li Tiantian Guo Peng Wang Yingxia Li 《Journal of carbohydrate chemistry》2013,32(9):506-519
A bidesmosidic triterpene saponin, flaccidoside II, which was isolated from Di Wu, a Chinese folk medicine from dry rhizome of Anemone flaccida Fr. Schmidt, was efficiently synthesized in a convergent approach. We employed two glycosyl trichloroacetimidate donors in a one-pot reaction as a key step. [Supplementary materials are available for this article. Go to the publisher's online edition of the Journal of Carbohydrate Chemistry for the following free supplemental resource(s): 1H NMR, 13C NMR and HR mass spectra for all synthesized compounds, 2, 6, 9-11, and Flaccidoside II (1) 相似文献
155.
156.
Depression is on the rise globally and expected to lead in global burden of diseases by 2030. The current therapy has serious limitations in terms of safety, efficacy, tolerability and therapeutic success. This review, based on the literature of the last decade, is aimed at exploring the preclinical profile of plant-based saponins (the abundant secondary metabolite) as an emerging therapy for depression. Enough scientific evidences reflect that saponins promote neurogenesis, restore monoaminergic tone and enhance neurotrophic factors. In multiple stress models, they have exhibited adaptogenic effects via normalising hypothalamus–pituitary–adrenal axis, corticosterone levels and oxidative stress. Scientific data revealed neuroprotective effect of saponins by inhibiting apoptosis and intraneuronal calcium dynamics. Many plants possessing saponins as their principal antidepressant moiety need investigation at clinical level. Last decade literature revealed numerous preclinical reports supporting the role of saponins as natural cure for depression and justified their inclusion in antidepressant drug discovery programs. 相似文献
157.
Jens Linnek Anne‐Claire Mitaine‐Offer Thomas Paululat Marie‐Aleth Lacaille‐Dubois 《Magnetic resonance in chemistry : MRC》2012,50(12):798-802
From the branches of Pittosporum senacia Putterlick (Pittosporaceae), two new triterpenoid saponins, senaciapittosides A and B (1, 2), were isolated. Their structures were elucidated by extensive analysis of one‐ and two‐dimensional nuclear magnetic resonance spectroscopy, high‐resolution electrospray ionization mass spectrometry (HR‐ESIMS) and chemical evidence as 3‐O‐[β‐d ‐glucopyranosyl‐(1 → 2)]‐[α‐l ‐arabinopyranosyl‐(1 → 3)]‐[α‐l ‐arabinofuranosyl‐(1 → 4)]‐β‐d ‐glucuronopyranosyl oleanolic acid 28‐O‐β‐d ‐glucopyranosyl ester (1) and 3‐O‐[β‐d ‐glucopyranosyl‐(1 → 2)]‐[α‐l ‐arabinopyranosyl‐(1 → 3)]‐[α‐l ‐arabinofuranosyl‐(1 → 4)]‐β‐d ‐glucuronopyranosyl‐22‐O‐α‐l ‐arabinopyranosyl‐21‐acetoxy R1‐barrigenol (2). Compound 2 presents an unusual glycosylation at C‐22 of its aglycone. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
158.
Łukasz Pecio Dariusz Jędrejek Milena Masullo Sonia Piacente Wiesław Oleszek Anna Stochmal 《Magnetic resonance in chemistry : MRC》2012,50(11):755-758
The revised structures of avenacosides A and B and a new sulfated steroidal saponin isolated from grains of Avena sativa L. were elucidated. Their structures and complete NMR assignments are based on 1D and 2D NMR studies and identified as nuatigenin 3‐O‐{α‐l ‐rhamnopyranosyl‐(1→2)‐[β‐D‐glucopyranosyl‐(1→4)]‐β‐d ‐glucopyranoside}‐26‐O‐β‐d ‐glucopyranoside (1), nuatigenin 3‐O‐{α‐l ‐rhamnopyranosyl‐(1→2)‐[β‐d ‐glucopyranosyl‐(1→3)‐β‐d ‐glucopyranosyl‐(1→4)]‐β‐d ‐glucopyranoside}‐26‐O‐β‐d ‐glucopyranoside (2), and nuatigenin 3‐O‐{α‐l ‐rhamnopyranosyl‐(1→2)‐[β‐d ‐6‐O‐sulfoglucopyranosyl‐(1→4)]‐β‐d ‐glucopyranoside}‐26‐O‐β‐d ‐glucopyranoside (3). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
159.
Xia Li Jianping Zhao Xiaoran Li Yanli Liu Qiongming Xu Ikhlas A. Khan Shilin Yang 《Helvetica chimica acta》2015,98(4):496-508
Five new triterpenoid saponins, oleiferosides I–M ( 1 – 5 , resp.) were isolated from the roots of Camellia oleifera Abel . Their structures were elucidated by a combination of 1D‐ and 2D‐NMR spectroscopy, mass spectrometry, and chemical methods. All the compounds were identified as oleanane‐type saponins with sugar moieties linked to C(3) of the aglycone. In addition, cytotoxic activities of these saponins were evaluated against four human tumor cell lines (A549, B16, BEL‐7402, and MCF‐7) by using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) in vitro assay. All of the compounds showed significant cytotoxic activities against the tested cell lines. 相似文献
160.
Yan Shao Dan‐Wei Ou‐Yang Liang Cheng Wen Gao Xiao‐Xiang Weng De‐Yun Kong 《Helvetica chimica acta》2015,98(5):683-690
Three new pentacyclic triterpenoids, named centellasaponins G, H, and F ( 1 – 3 , resp.), together with four known compounds, 4 – 7 , were isolated from the whole plants of Centella asiatica. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D‐ and 2D‐NMR and HR‐MS experiments, and by comparison with literature data. 相似文献