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排序方式: 共有240条查询结果,搜索用时 937 毫秒
91.
92.
Three new oleanane-type triterpenoid saponins, ilexhainanoside C, D and E, all with 24, 28-dioic acid groups, were isolated from the leaves of Ilex hainanensis. They were 3beta-hydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(1), 3beta, 19alpha-dihydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(2) and 3beta, 29-dihydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(3). The structures of these three new compounds were elucidated and complete assignments of the (1)H and (13)C NMR spectroscopic data were achieved by 1D and 2D NMR experiments [heteronuclear single quantum coherence (HSQC), HMBC and rotational nuclear Overhauser effect spectroscopy (ROESY)]. 相似文献
93.
Zhangpei Zhu Jiajia Shen Yangfan Xu Huimin Guo Dian Kang Tengjie Yu He Wang Wenshuo Xu Guangji Wang Yan Liang 《Journal of mass spectrometry : JMS》2019,54(8):684-692
Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) is an excellent analytical technique for rapid analysis of a variety of molecules with straightforward sample pretreatment. The performance of MALDI‐TOF MS is largely dependent on matrix type, and the development of novel MALDI matrices has aroused wide interest. Herein, we devoted to seek more robust MALDI matrix for herbal saponins than previous reported, and ginsenoside Rb1, Re, and notoginsenoside R1 were used as model saponins. At the beginning of the present study, 2,5‐dihydroxybenzoic acid (DHB) was found to provide the highest intensity for saponins in four conventional MALDI matrices, yet the heterogeneous cocrystallization of DHB with analytes made signal acquisition somewhat “hit and miss.” Then, graphene oxide (GO) was proposed as an auxiliary matrix to improve the uniformity of DHB crystallization due to its monolayer structure and good dispersion, which could result in much better shot‐to‐shot and spot‐to‐spot reproducibility of saponin analysis. The satisfactory precision further demonstrated that minute quantities of GO (0.1 μg/spot) could greatly reduce the risk of instrument contamination caused by GO detachment from the MALDI target plate under vacuum. More importantly, the sensitivity and linearity of the standard curve for saponins were improved markedly by DHB‐GO composite matrix. Finally, the application of detecting the Rb1 in complex biological sample was exploited in rat plasma and proved it applicable for pharmacokinetic study quickly. This work not only opens a new field for applications of DHB‐GO in herbal saponin analysis but also offers new ideas for the development of composite matrices to improve MALDI MS performance. 相似文献
94.
Two new glycosides of phytolaccagenin and 2β-hydroxyoleanoic acid, namely bonushenricoside A (3) and bonushenricoside B (5) together with four known saponins, respectively compounds 3-O-L-α-arabinopyranosyl-bayogenin-28-O-β-glucopyranosyl ester (1), 3-O-β-glucuronopyranosyl-2β-hydroxygypsogenin-28-O-β-glucopyranosyl ester (2), 3-O-β-glucuronopyranosyl-bayogenin-28-O-β-glucopyranosyl ester (4) and 3-O-β-glucuronopyranosyl-medicagenic acid-28-β-xylopyranosyl(1→4)-α-rhamnopyranosyl(1→2)-α-arabinopyranosyl ester (6) were isolated from the roots of Chenopodium bonus-henricus L. The structures of the compounds were determined by means of spectroscopic methods (1D and 2D NMR, IR and HRMS). The MeOH extract and compounds were tested for cytotoxic activity on five leukemic cell lines (HL-60, SKW-3, Jurkat E6-1, BV-173 and K-562). In addition, the ability of metanolic extract and saponins to modulate the interleukin-2 production in PHA/PMA stimulated Jurkat E6-1 cells was investigated as well. 相似文献
95.
Triterpenoid Saponins from Clematis tangutica 总被引:2,自引:0,他引:2
Clenlall\vlanglllica(Maxim).KorshisaTibetanherbandhasbeenusedtotreatindigestionandskindiseasesl.Nophytochemicalworkonthisplanthasbeenreportedinliterature.Inourwork.someglycosideswereobtainedtyomaerialpartofthisplant.Inthispaper.thestructureelucidationoftwonewtriterpenoidsaponins.tanguticosideAandBaredescribed.Onmineralacidhydrolysis.both1and2yieldedthesameaglycone.BycomparingMP.MS,'HNMRand13CNMRspectratheaglyconewasdeterminedtobehederagenin=.Glucoseandrhamnosewereobtainedfromhydrolysis… 相似文献
96.
Linyao Yang Jiangchao Du Rongtao Li Fei Yu Jindong Zhong 《Molecules (Basel, Switzerland)》2021,26(21)
Investigation of the n-BuOH extract of the aerial parts of Elsholtzia bodinieri led to the isolation of seven new triterpenoid saponins, Bodiniosides S–Y (1–7, resp.). Their strictures were elucidated on the basis of spectroscopic techniques, including HSQC, HSBC, and HSQC–TOCSY experiments, together with acid hydrolysis and GC analysis. The anti-influenza activities of compounds 1–7 were evaluated against A/WSN/33/2009 (H1N1) virus in MDCK cells. The results showed that compounds 2 and 5 exhibited moderate anti-influenza activities against A/WSN/33/2009 (H1N1), with inhibition rates of 35.33% and 24.08%, respectively. 相似文献
97.
Barbara Thiem Dariusz Kruszka Natalia Turowska Elwira Sliwinska Viktor Berge Magorzata Kikowska 《Molecules (Basel, Switzerland)》2021,26(22)
Linnaea borealis L. (Twinflower)—a dwarf shrub in the Linnaeeae tribe of Caprifoliaceae family—is distributed across the Northern Hemisphere. By means of this study, a reliable protocol for efficient micropropagation of uniform L. borealis L. var. borealis plantlets has been provided for the first time; callus culture was also established. Different initial explants, types of cultures, media systems, and plant growth regulators in Murashige and Skoog (MS) media were tested. Agitated shoot cultures in the liquid media turned out to be the best system for the production of sustainable plant biomass. After stabilization of the callus lines, the highest growth index (c.a. 526%) was gained for callus maintained on MS enriched with picloram. TLC and UHPLC-HESI-HRMS analysis confirmed the presence of phenolic acids and flavonoids, and for the first time, the presence of iridoids and triterpenoid saponins in this species. Multiplication of L. borealis shoot culture provides renewable raw material, allowing for the assessment of the phytochemical profile, and, in the future, for the quantitative analyses and the studies of the biological activity of extracts, fractions, or isolated compounds. This is the first report on in vitro cultures of traditionally used L. borealis rare taxon and its biosynthetic potential. 相似文献
98.
《Biomedical chromatography : BMC》2017,31(6)
Dantonic pill, consisting of Salviae miltiorrhize , Panax notoginseng and Borneol , is a widely used compound Chinese medicine for preventing and treating ischemic cardiovascular diseases in China. In the present study, an original and sensitive method for simultaneous determination of tanshinol (i.e. danshensu), protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 in rat plasma by liquid chromatography–tandem mass spectrometry operated in positive/negative ion switching mode was established and validated. The lower limits of quantification for tanshinol, protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 were 5, 0.5, 1, 0.5, 0.5 and 2 ng/mL, respectively. All of the calibration curves showed good linearity over the investigated concentration range (r > 0.99). Validation results demonstrated that the above compounds were accurately, precisely and robustly quantified in rat plasma. The method was successfully applied to characterize the pharmacokinetic profiles of all six compounds in rats following a single oral administration of Dantonic pill. 相似文献
99.
100.
A new HPLC coupled with evaporative light scattering detection method was established for the simultaneous determination of seven triterpenoids and triterpenoid saponins in Folium Ilicis Purpureae traditional Chinese medicinal herb derived from the leaf of Ilex purpurea, namely, 3-omicron-beta-D-glucopyranosyl (1-->2)-beta-D-[6-omicron-methyl-glucuronopyranosyl]-28-omicron-beta-D-glucopyranosyl oleanolic acid (SQ-1), pedunculoside (SQ-2), 23-hydroxytormentic acid 28-omicron-beta-D-glucopyranoside (SQ-3), 23-hydroxytormentic acid (SQ-4), rutundic acid (SQ-5), ilexoside B (SQ-6), and ursolic acid (SQ-7). The optimal chromatographic conditions were achieved on a C18 column with a linear gradient elution of mobile phase A: deionized water-isopropyl alcohol-THF-acetic acid (90:10:6:1, v/v) and B: methanol-isopropyl alcohol-THF-acetic acid (90:10:6:1, v/v) at the flow rate of 1.0 mL/min; temperature for drift tube was set at 98degreesC and nitrogen flow rate was 2.8 L/min. All calibration curves of the seven compounds showed good linear regression (r2 > 0.995) within test ranges. The developed method has good repeatability for quantitation of all analytes interested with overall intraday and interday variation of less than 4.1%. The LOD (S/N = 3) and LOQ (S/N = 10) were less than 0.13 and 0.26 microg/mL, respectively, for all analytes. The established method was successfully used to evaluate the quality of Folium Ilicis Purpureae samples of different collections. 相似文献