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目的运用火焰原子吸收光谱法测定中药土大黄根中的Fe、Zn、Mg、Ca等4种金属元素的含量。方法用浓HNO3-HClO4消解样品,采用标准曲线法测定其4种金属元素含量。结果所测的样品中含有丰富的人体必需微量元素,尤其是Ca含量极高。方法回收率在96.90%~102.3%之间,样品相对偏差小于5%。结论方法简单、准确,结果令人满意。  相似文献   
2.
Two new compounds,corialins A(1) and B(2) were isolated from Coriaria nepalensis Wall.These new compounds were established as 7-hydroxy-3-[2,3-acetonide-(3-methylbutane)]coumarin(1) and 3-O-β-D-glucopyranosyl-3,4,5-trihydroxy-1-(3- methyl-2-butenyl)-benzene(2),on the basis of 1D and 2D NMR techniques.  相似文献   
3.
白花刺参中的咖啡酰基奎宁酸成分   总被引:16,自引:0,他引:16  
著名藏药白花刺参Morina nepalensis var. albaHand. Mazz.的全株的水溶性部分通过硅胶、RP-8、Sephadex LH-20柱层析分离,得到4个咖啡酰基奎宁酸1~4 ,运用光谱和波谱方法, 分别鉴定为3-O-咖啡酰基奎宁酸(1)、3,5-O-双咖啡酰基奎宁酸(2)、3,4-O-双咖啡酰基-奎宁酸(3)和4,5-O-双咖啡酰基-奎宁酸(4). 应用2D NMR图谱, 对其氢和碳的化学位移进行全归属, 并报道1, 2在氘代甲醇和氘代二-甲亚砜两种溶剂下测定1H和13C化学位移. 4个化合物都是首次分离自刺参属植物.  相似文献   
4.
From the whole plant of Morina nepalensis var. alba Hand.‐Mazz., two new acylated flavonoid glycosides ( 1 and 2 ), together with four known flavonoid glycosides ( 3–6 ), were isolated. Their structures were determined to be quercetin 3‐O‐[2″′‐O‐(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐galactopyranoside (monepalin A, 1 ), quercetin 3‐O‐[2″′‐O‐(E)‐caffeoyl]‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐glucopyranoside (monepalin B, 2 ), quercetin 3‐O‐α‐L ‐arabinopyranosyl‐(1→6)‐β‐D ‐galactopyranoside (rumarin, 3 ), quercetin 3‐O‐β‐D ‐galactopyranoside ( 4 ), quercetin 3‐O‐β‐D ‐glucopyranoside ( 5 ) and apigenin 4O‐β‐D ‐glucopyranoside ( 6 ). Their structures were determined on the basis of chemical and spectroscopic evidence. Complete assignments of the 1H and 13C NMR spectra of all compounds were achieved from the 2D NMR spectra, including H–H COSY, HMQC, HMBC and 2D HMQC‐TOCSY spectra. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
5.
Gynura nepalensis D.C. (family: Asteraceae) has abundant uses in the alternative medicinal practice, and this species is commonly used in the treatment of diabetes, rheumatism, cuts or wounds, asthma, kidney stones, cough, urinary tract bleeding, gall bladder stones, hepatitis, diarrhea, hemorrhoids, constipation, vomiting, fertility problems, blood poisoning, septicemia, skin allergy, indigestion, high cholesterol levels, and so on. This study aims to investigate the hepatoprotective and antioxidant potential of the methanol extract of the Gynura nepalensis D.C. (GNME) along with chemical profiling with phytochemical screening. Moreover, prospective phytocompounds have been screened virtually to present the binding affinity of the bioactive components to the hepatic and oxidative receptors. In the hepatoprotective study, alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total protein (TP), and lipid peroxidation (LP) and total bilirubin (TB) have been assessed, and in the antioxidant study, the DPPH free radical scavenging, total antioxidant flavonoid, and phenolic contents were determined. Moreover, the molecular binding affinity of the bioactive component of the plant has been analyzed using PyRx AutoDock Vina, Chimera, and Discovery Studio software. The plant extract showed dose-dependent hepatoprotective potential (p < 0.05, 0.01, 0.001) as well as strong antioxidant properties. Moreover, hepatoprotective and antioxidant molecular docking studies revealed a result varying from −2.90 kcal/mol to −10.1 kcal/mol. 4,5-dicaffeoylquinic acid and chlorogenic acid revealed the highest binding affinity among the selected molecules. However, the plant showed portent antioxidant and hepatoprotective properties in the in vitro, in vivo, and in silico models, and it is presumed that the hepatoprotective properties of the plant extract have occurred due to the presence of the vast bioactive chemical compounds as well as their antioxidant properties. Therefore, advanced studies are recommended to elucidate the pharmacological properties of the plant extracts.  相似文献   
6.
Four new ursane‐type saponins, monepalosides C–F, together with a known saponin, mazusaponin II, were isolated from Morina nepalensis var. alba Hand.‐Mazz. Their structures were determined to be 3‐O‐α‐L ‐arabinopyranosyl‐(1 → 3)‐&[alpha;‐L ‐rhamnopyranosyl‐(1 → 2)]‐α‐L ‐arabinopyranosylpomolic acid 28‐O‐β‐D ‐glucopyranosyl‐(1 → 6)‐β‐D ‐glucopyranoside (monepaloside C, 1 ), 3‐O‐α‐L ‐arabinopyranosyl‐(1 → 3)‐&[alpha;‐L ‐rhamnopyranosyl‐(1 → 2)]‐β‐D ‐xylopyranosylpomolic acid 28‐O‐β‐D ‐glucopyranosyl‐(1 → 6)‐β‐D ‐glucopyranoside (monepaloside D, 2 ), 3‐O‐α‐L ‐arabinopyranosyl‐(1 → 3)‐&[beta;‐D ‐glucopyranosy‐(1 → 2)]‐α‐L ‐arabinopyranosylpomolic acid 28‐O‐β‐D ‐glucopyranosyl‐(1 → 6)‐β‐D ‐glucopyranoside (monepaloside E, 3 ) and 3‐O‐β‐D ‐xylopyranosylpomolic acid 28‐O‐β‐D ‐glucopyranoside (monepaloside F, 4 ) on the basis of chemical and spectroscopic evidence. 2D NMR techniques, including 1H–1H COSY, HMQC, 2D HMQC‐TOCSY, HMBC and ROESY, and selective excitation experiments, including SELTOCSY and SELNOESY, were utilized in the structure elucidation and complete assignments of 1H and 13C NMR spectra. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
7.
白花刺参中两个新三萜皂苷   总被引:2,自引:0,他引:2  
从著名藏药白花剌参(Morina nepalensis var.alba Hand-Mazz)全草的水溶 性部分中分离得到两个新的乌苏烷型三萜皂苷,命名为剌参苷A(1)和剌参苷B(2). 应用2DNMR新技术,包括^1H-^1H COSY,HSQC,HMBC,2D HMQC-TOCSY,ROESY,以 及选择性激发实验1D SELTOCSY和1D SELNOESY,并结合化学方法,确定它们的结构 分别为3-O-a-L-阿拉伯吡喃糖基-(1→3)-α-L-阿拉伯吡喃糖基坡摸醇酸28-O-β -D-葡萄吡喃基-(1→6) -β-D-葡萄吡喃糖苷(1)和3-O-a-L-阿拉伯吡喃糖基-( 1→3)-β-D-木糖吡喃基坡摸醇酸28-O-β-D-葡萄吡喃基-(1→6) -β-D-葡萄吡喃 糖苷(2),并对其氢和碳的化学位移进行了全归属。  相似文献   
8.
One new triterpenoid saponin,monepaloside K(1) was isolated from the water-soluble part of the whole plant of a famous Tibetan medicinal herb,morina neplaensis var. alba Hand.-Mazz.Its structure was determined to be 3-O-α-L-arabinopyranosyl-(1→3)-β-D-xylopyranosyl siaresinolic acid on the basis of spectroscopic evidences,especially 2D NMR techniques.  相似文献   
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