4 resultados para Thelephora terrestris

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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石竹色革菌(Thelephora caryophyllea)采于吉林省长白山自然保护区的阔叶林沙地上,为中国革菌一新纪录种。本文给出了该菌的详细描述,并对其近似种进行了比较研究。

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The underivatized saponins from Tribulus terrestris and Panax ginseng have been investigated by electrospray ionization multi-stage tandem mass spectrometry (ESI-MSn). In ESI-MS spectra, a predominant [M + Na](+) ion in positive mode and [M - H](-) ion in negative mode were observed for molecular mass information. Multi-stage tandem mass spectrometry of the molecular ions was used for detailed structural analysis. Fragment ions from glycoside cleavage can provide information on the mass of aglycone and the primary sequence and branching of oligosaccharide chains in terms of classes of monosaccharides. Fragment ions from cross-ring cleavages of sugar residues can give some information about the linkages between sugar residues. It was found that different alkali metal-cationized adducts with saponins have different degrees of fragmentation, which may originate from the different affinity of a saponin with each alkali metal in the gas phase. ESI-MSn has been proven to be an effective tool for rapid determination of native saponins in extract mixtures, thus avoiding tedious derivatization and separation steps.

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目的:研究蒺藜(Tribulus terrestris L.)中生物活性物质。方法:用硅胶柱色谱、HPLC进行分离,根据光谱数据鉴定其结构。结果:分离纯化得到两种呋甾皂苷,确定其结构为26-O-β-D-吡喃葡糖基-(25R,S)-5α-呋甾-12-羰基-20(22)-烯基-3β,26-二醇-3-O-β-D吡喃葡糖基(1→4)-β-D-吡喃半乳糖苷(I);26-O-β-D吡喃葡糖基-(25R)-5α-呋甾-12-羰基-3β,22α,26-三醇-3-O-β-D-吡喃葡糖基(1→2)-β-D-吡喃半乳糖苷(Ⅱ)。结论:I,Ⅱ均为新化合物

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Using electrospray ionization mass spectrometry (MS) combined with sequential tandem MS(ESI-MSn), two major steroidal saponins extracted from Tribulus terrestris were studied, and considerable useful structural information was obtained. The structure of the proposed known steroidal saponin was verified, and the structure of the unknown saponin was investigated using MSn experiments. Some special fragment ions were also observed, and the corresponding fragmentation mechanisms were investigated which are characteristic for steroidal saponins and can give some information on the linkage position of some sugar groups in saponins. This methodology has been established as a powerful tool for the rapid, comparative analysis of mixtures such as crude plant extracts. (C) 1998 John Wiley & Sons, Ltd.