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91.
菝葜中黄酮和芪类成分的研究   总被引:23,自引:0,他引:23  
目的:为阐明百合科植物菝葜的有效成分,对其根茎进行了化学成分研究。方法:运用层析手段和波谱方法分离并鉴定了5个酚性化合物。结果:它们的结构为二氢山奈酚(dihydrokaempferol,1),3,5,4′—三羟基芪(3,5,4′-trihydroxystilbene,2),3,5,2′,4′—四羟基芪(3,5,2′,4′-tetrahydroxystilbene,3),二氢山奈酚3—O-α—L—鼠李糖等(黄杞苷,dihydrokaempferol 3-O-α-L-rhamnoside,engletin,4),槲皮素4′—0-β—D—葡萄糖等(quercetin4′—O-β—D—glucoside,5)。结论:5个化合物均为首次从菝葜中得到,其中化合物1,4,5为首次从菝葜属植物中得到。  相似文献   
92.
淫羊藿总黄酮对体外培养成骨细胞的影响   总被引:40,自引:0,他引:40       下载免费PDF全文
目的:观察淫羊藿总黄酮对体外培养成骨细胞的作用。方法:取新生1-3d SD大鼠头盖骨用酶消化法分离成骨细胞。第3代细胞经MTT法、茜素红染色法观察淫羊藿总黄酮对体外培养成骨细胞增殖、矿化结节形成的影响。结果:淫羊藿总黄酮1-10μg/ml浓度具有显著的促进成骨细胞增殖及提高矿化结节形成数量的作用。结论:淫羊藿总黄酮具有促进体外成骨细胞增殖及分化成熟的作用。  相似文献   
93.
用高效液相色谱法(HPLC)成功地分离和制备了芦苇叶中天然抗氧化成分黄酮类化合物,并进行了定性和定量分析。  相似文献   
94.
The effect of grapefruit juice on the urinary excretion of 7-hydroxycoumarin after oral administration of 10 mg coumarin, as an index of cytochrome P450 dependent coumarin metabolism, has been investigated in an open, randomised cross over study in 13 healthy volunteers (7 female, 6 male).The percentage of 7-hydroxycoumarin found in urine was significantly decreased up to 8 h after simultaneous intake of 300 ml grapefruit juice. If the same volume of juice was swallowed 30 min prior to the administration of coumarin, 7-hydroxycoumarin excretion was delayed by up to 6 h. MRTexcr. of coumarin was 70 % extended by coadministration of grapefruit juice.It appears that grapefruit flavonoids inhibit cytochrome P450 2A dependent metabolic pathways. The mechanism of cytochrome P450 inhibition by these flavonoids is still poorly understood.  相似文献   
95.
甘草黄酮的提取分离和含量测定   总被引:21,自引:0,他引:21  
目的:充分利用甘草资源。方法:从提取过甘草酸的废渣中提取甘草黄酮并进行含量测定。结果:用碱酸处理和用大孔树脂处理黄酮含量高,收率也高。结论:从甘草废渣中提取甘草黄酮具有较好的社会效益和经济效益  相似文献   
96.
目的:观察高良姜、大高良姜、红豆蔻黄酮类成分对胃溃疡寒证大鼠环核苷酸水平及交感神经-肾上腺轴的影响,探讨3味山姜属中药温热药性的物质基础。方法:采用灌服冰知母水煎液与15%冰乙酸制备大鼠胃溃疡寒证模型,以干姜姜辣素为阳性对照,采用酶联免疫吸附试验(ELISA)法测定腺苷酸环化酶(AC)、磷酸二酯酶2(PDE2)、环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)、促肾上腺皮质激素(ACTH)、多巴胺β羟化酶(D-β-H)含量。结果:与空白组比较,胃溃疡寒证模型组大鼠胃组织AC、cAMP含量及cAMP/cGMP比值显著降低,PDE2含量显著升高(P<0.01)。与模型组比较,高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织AC含量升高;高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织PDE2含量显著降低,cAMP含量、cAMP/cGMP比值显著升高(P<0.01或P<0.05)。结论:3味山姜属中药黄酮类成分通过调节胃溃疡寒证大鼠环核苷酸水平从而促进交感神经-肾上腺轴功能活动的作用,也体现出黄酮类成分药性温热。  相似文献   
97.
Metabolic syndrome (MBS) is a widespread disease that has strongly related to unhealthy diet and low physical activity, which initiate more serious conditions such as obesity, cardiovascular diseases and type 2 diabetes mellitus. This study aimed to examine the therapeutic effects of morin, as one of the flavonoids constituents, which widely exists in many herbs and fruits, against some metabolic and hepatic manifestations observed in MBS rats and the feasible related mechanisms. MBS was induced in rats by high fructose diet feeding for 12 weeks. Morin (30 mg/kg) was administered orally to both normal and MBS rats for 4 weeks. Liver tissues were used for determination of liver index, hepatic expression of glucose transporter 2 (GLUT2) as well as both inflammatory and fibrotic markers. The fat/muscle ratio, metabolic parameters, systolic blood pressure, and oxidative stress markers were also determined. Our data confirmed that the administration of morin in fructose diet rats significantly reduced the elevated systolic blood pressure. The altered levels of metabolic parameters such as blood glucose, serum insulin, serum lipid profile, and oxidative stress markers were also reversed approximately to the normal values. In addition, morin treatment decreased liver index, serum liver enzyme activities, and fat/muscle ratio. Furthermore, morin relatively up-regulated GLUT2 expression, however, down-regulated NF-κB, TNF-α, and TGF-β expressions in the hepatic tissues. Here, we revealed that morin has an exquisite effect against metabolic disorders in the experimental model through, at least in part, antioxidant, anti-inflammatory, and anti-fibrotic mechanisms.  相似文献   
98.
Context: The flowers of Trollius chinensis Bunge (Ranunculaceae), used for respiratory tract infections, mainly contain flavonoids, phenolic acids, and alkaloids; however, the effective components are debatable because of their unclear in vivo activities.

Objective: This study investigates the effective components from the perspectives of biotransformation and absorption.

Materials and methods: Both single person derived- and multiple people-derived intestinal florae were used to investigate the biotransformation of aqueous extract of the flowers of T. chinensis (AEOF) at the concentrations of 15.0, 30.0, and 60.0?mg/mL, respectively, for 72?h. Both human colon adenocarcinoma cell line (Caco-2) monolayers and everted gut sacs were employed to evaluate the intestinal absorption of the intestinal bacterial transformed AEOF at the concentrations of 10, 20, and 30?mg/mL, respectively, for 180?min.

Results: 2″-O-β-l-Galactopyranosylorientin, orientin, vitexin, quercetin, veratric acid, proglobeflowery acid, and trolline in AEOF were not transformed by intestinal bacteria, while isoquercetin and trollioside were completely transformed. The Papp values of 2″-O-β-l-galactopyranosylorientin, orientin, and vitexin calculated based on the experimental data of intestinal absorption were at the levels of 10?5, whereas those of veratric acid, proglobeflowery acid, and trolline were at 10?4. The mass ratio of flavonoids to phenolic acids to alkaloids changed from 16:10:7 to 9:12:8 before and after absorption.

Discussion and conclusion: The dominant position of flavonoids was replaced by phenolic acids after absorption. In addition to flavonoids which are usually considered as the dominant effective ones, phenolic acids and alkaloids should be also very important for the efficacy of these flowers.  相似文献   
99.
赶黄草木脂素及黄酮类成分抑制肝癌细胞增殖的作用   总被引:1,自引:0,他引:1  
目的:研究赶黄草中木脂素类及黄酮类成分体外抑制肝癌细胞增殖的作用。方法:采用MTT法评价赶黄草中8个木脂素(1~8)和5个黄酮(9~13)体外抗人肝癌细胞SMMC-7721和Hep G2增殖的活性以及对正常肝细胞LO_2活力的影响。运用Image-i T DEAD Green/Hoechst 33342荧光双染和高内涵成像分析化合物1对SMMC-7721细胞的影响。结果:化合物1、6、8~11可抑制SMMC-7721的增殖,6、9、11、13可抑制Hep G2的增殖。除化合物11以外,以上化合物对正常肝细胞LO_2均无明显细胞毒作用,且化合物3、4、5、13还可促进LO_2增殖。结论:赶黄草中部分木脂素及黄酮类成分不仅具有抑制肝癌细胞增殖的作用,而且对正常肝细胞无毒作用,甚至可保护正常肝细胞,表现出较好的选择性。  相似文献   
100.
LiWK 《中国药学》1996,5(2):109-109
StudiesontheChemicalConstituentsofEpimediumkoreanumNakaiandEpimediumwanshanenseS.Z.HeetGuoPh.D.DegreeWen-KuiLi1SupervisorsPro...  相似文献   
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