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A PEG‐modified reversed migration MEEKC method was developed for simultaneous determination of six polyynes, including oplopandiol, falcarindiol, oplopandiol acetate, (11S, 16S, 9Z)‐9,17‐octadecadiene‐12,14‐diyne‐1,11,16‐triol,1‐acetate, oplopantriol B, and oplopantriol A, in Oplopanax horridus and Oplopanax elatus. The running buffer containing 0.8% v/v ethyl acetate, 3.8% w/v SDS, 6.6% v/v n‐butanol in 20 mM phosphate buffer (pH 2.5), followed by mixing with propan‐2‐ol at 30% v/v and PEG‐1000 at 15% w/v, was applied in the analysis. The proposed method was successfully applied to determine the six polyynes in five samples of Oplopanax horridus and one of O. elatus. The result showed that the types and amounts of polyynes present were obviously different when comparing the two herbs. Besides, the developed PEG‐modified reversed MEEKC method might be suitable for the analysis of hydrophobic analytes in herbal medicines.  相似文献   
2.
ChemicalStudiesontheGlycosidesintheLeavesofOplopanaxElatusNakai(Ⅳ)*WANGGuang-shuandXUJing-da(NormanBethuneUniversityofMedical...  相似文献   
3.
Four new phenolic derivatives, including two phenylpropanoid glycosides, one benzoate glycoside, and one lignan glycoside, together with one known glyceride, were isolated from the root bark of Oplopanax horridus. The structures of the new compounds were elucidated as 3‐{4‐[(6‐O‐acetyl‐β‐D ‐glucopyranosyl)oxy]‐3,5‐dimethoxyphenyl}propanoic acid ( 1 ), (+)‐[5,6,7,8‐tetrahydro‐7‐(hydroxymethyl)‐10,11‐dimehoxydibenzo[a,c][8]annulen‐6‐yl]methyl β‐D ‐glucopyranoside ( 2 ), (+)‐methyl 4‐[6‐O‐{3‐hydroxy‐3‐methyl‐5‐(1‐methylpropyl)oxy]‐5‐oxopentanoyl}‐4‐O‐(β‐D ‐glucopyranosyl)‐β‐D ‐glucopyranosyl)oxy]‐3‐methoxybenzoate ( 3 ), and 2‐methoxy‐4‐[(1E)‐3‐methoxy‐3‐oxoprop‐1‐en‐1‐yl]phenyl 6‐O‐{3‐hydroxy‐3‐methyl‐5‐[(1‐methylpropyl)oxy]‐5‐oxopentanoyl‐4‐Oβ‐d‐ glucopyranosyl‐β‐d‐ glucopyranoside ( 4 ) on the basis of spectroscopic techniques including NMR and MS analyses. The known compound was identified as glycer‐2‐yl ferulate ( 5 ) by comparing its physical and spectral data with those reported in the literature.  相似文献   
4.
东北刺人参的微量元素测定分析   总被引:3,自引:0,他引:3  
用原子吸收光谱法测定了刺人参和人参的8种微量元素.结果显示,刺人参茎的8种微量元素的总量高于刺人参根的总量,茎的总量为281.42×10-6,根的总量为230.75×10-6;人参的8种元素总量为218.07×10-6;Fe、Zn和Mn3元素加起来的含量占总量的80%以上。可见这3元素是这两味药材的主要微量元素成分。然而刺人参的Mn含量特别高,人参的Zn含量特别高,这正是刺人参不同于人参的地方,说明刺人参更易富集元素Mn.  相似文献   
5.
Oplopanax horridus, widely distributed in North America, is an herbal medicine traditionally used by Pacific indigenous peoples for various medical conditions. After oral ingestion, constituents in O. horridus extract (OhE) could be converted to their metabolites by the enteric microbiome before absorption. In this study, in order to mimic gut environment, the OhE was biotransformed using the enteric microbiome of healthy human subjects. For accurate and reliable data collection with optimized approaches in sample preparation and analytical conditions, ultra-performance liquid chromatography and quadrupole time-of-flight mass spectrometry were used to characterize parent constituents and their metabolites. In the extract, 20 parent compounds were identified including polyynes, sesquiterpenes, monoterpeondids, phenylpropanoids and phenolic acids. After the biotransformation, a total of 78 metabolites were identified, of which 37 belonged to polyynes metabolites. The common biotransformation pathways are hydroxylation, acetylization, methylation and demethylation. Based on the pathway distributions, the metabolism signature of OhE has been explored. The metabolism pathways of OhE compounds are dependent on their structural classifications and hydrophilic/hydrophobic properties. In summary, with comprehensive analysis, we systematically investigated human microbiome-derived OhE metabolites. The enteric microbial metabolism signature provides novel information for future effective use of O. horridus.  相似文献   
6.
野生东北刺人参茎挥发油化学成分研究   总被引:6,自引:0,他引:6  
张宏  张宏桂 《分析化学》1993,21(6):679-681
本文用GC/MS方法分离鉴定了产于中国东北的药用刺人参的茎中20种挥发油成份。其中主要成份为醇类(68.9%)、醛类(17.6%).萜类(4.1%)。  相似文献   
7.
The root of Oplopanax elatus (Nakai) Nakai has a well‐known history of use for the treatment of diseases such as neurasthenia, cardiovascular disorders, and cancer by the native people in northeast China. It is important to screen and identify the bioactive molecules from its root rapidly. Hereby, an off‐line two‐dimensional high performance liquid chromatography coupled with diode array detection and tandem time‐of‐flight mass spectrometry together with 2,2?‐diphenyl‐1‐picrylhydrazyl was established to screen antioxidants from the root of O. elatus. A Waters cyanogen column (150 × 3.9 mm, id, 4 μm) was used for the first dimensional liquid chromatography, while a Hypersil BDS‐C18 column (250 × 4.6 mm, id, 5 μm) was installed for the second dimension liquid chromatographic analysis. Twenty‐eight compounds had been tentatively identified from the methanol extract of the air‐dried root of O. elatus including six polyynes and eight phenolic derivatives were screened with antioxidant activity. The developed method could be expedient for screening and identifying antioxidants from O. elatus.  相似文献   
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