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11.
中药菟丝子化学成分研究   总被引:32,自引:1,他引:32  
目的 :研究中药菟丝子的化学成分。方法 :聚酰酰和硅胶柱色谱进行分离 ,理化性质及光谱特征确定结构。结果 :从其乙醇提取物中分离并鉴定了 8个化合物 ,槲皮素-3-O-β-D-半乳糖-7-O-β-D-葡萄糖苷 (Ⅰ) ,槲皮素-3-O-β-D-半乳糖 (2→1)-β-D-芹糖苷 (Ⅱ ) ,金丝桃苷 (Ⅲ) ,异鼠李素 (Ⅳ) ,山柰酚 (Ⅴ) ,槲皮素 (Ⅵ) ,d-芝麻素(Ⅶ )和9(R) 羟基-d-芝麻素 (Ⅷ )。结论 :Ⅳ和Ⅶ为首次自菟丝子属植物中分得 ,Ⅰ ,Ⅱ和Ⅴ为菟丝子的特征性化学成分。  相似文献   
12.
Objective: We recently described the development of a comprehensive database for assessing phytoestrogen exposure in epidemiologic studies [1]. This paper describes the first application of this database and the primary sources of phytoestrogen consumption in non-Asian women. Methods: Four hundred and forty-seven randomly selected African-American, Latina, and white women, ages 50 79 years, residing in California's San Francisco Bay Area and participating as controls in an ongoing population-based case-control study of breast cancer, were included in the present analysis. Average daily consumption of each of seven phytoestrogenic compounds was determined for each woman by combining the values from the new database with food consumption reported on a food-frequency questionnaire. Results: Phytoestrogens in the non-Asian Bay Area diet appear to come primarily from: (1) traditional soy-based foods (e.g. tofu and soy milk); (2) "hidden" sources of soy (e.g. foods containing added soy protein is concentrate, or soy flour, e.g. many brands of doughnuts and white bread); and (3) a variety of foods which contain only low to moderate amounts of phytoestrogens per 100 grams but which are frequently consumed (e.g. coffee and orange juice). Conclusions: In the absence of a comprehensive assessment of various phytoestrogens in a wide variety of foods, epidemiologic studies could suffer from the effects of uncontrolled confounding by unmeasured sources of phytoestrogen exposure potentially leading to biased estimates of effect and misinterpretation of findings.  相似文献   
13.
Dietary lignan intakes and risk of pre- and postmenopausal breast cancer   总被引:5,自引:0,他引:5  
Lignans are plant compounds metabolized in the mammalian gut to produce the phytoestrogens enterolactone and enterodiol. Because estrogens have been linked to breast cancer etiology, lignans could affect breast cancer risk through modulation of endogenous estrogen metabolism or competitive inhibition with estrogen receptors. We examined breast cancer risk and dietary lignan intake in a population-based case-control study of 1,122 women with primary, incident, histologically confirmed breast cancer and 2,036 controls frequency matched to cases on age and county of residence as part of the Western New York Exposures and Breast Cancer (WEB) Study. Diet was assessed with a self-administered 104-item food frequency questionnaire and other relevant data were collected by detailed in-person interviews. Lignans were expressed as the sum of the dietary precursors secoisolariciresinol and matairesinol. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression, adjusting for age, total energy and other breast cancer risk factors. Premenopausal women in the highest quartile of dietary lignan intake had reduced breast cancer risk (OR = 0.66; 95% CI = 0.44-0.98). No association was observed between lignan intakes and postmenopausal breast cancer. Our results suggest that dietary lignans may be important in the etiology of breast cancer, particularly among premenopausal women.  相似文献   
14.
Phytoestrogens: a review of the present state of research   总被引:12,自引:0,他引:12  
Phytoestrogens are a diverse group of plant-derived compounds that structurally or functionally mimic mammalian estrogens and show potential benefits for human health. The number of articles published on phytoestrogens has risen dramatically in the past couple decades. Further research continues to demonstrate the biological complexity of phytoestrogens, which belong to several different chemical classes and act through diverse mechanisms. This paper discusses the classification of phytoestrogens, methods of identification, their proposed mechanisms of action and botanical sources for phytoestrogens. The effects of phytoestrogens on breast and prostate cancers, cardiovascular disease, menopausal symptoms and osteoporosis will also be examined including research on benefits and risks.  相似文献   
15.
复方五仁醇胶囊含药血清中木脂素类成分的UPLC-MS/MS分析   总被引:8,自引:0,他引:8  
窦志华  丁安伟  居文政  罗琳 《中成药》2007,29(4):550-555
目的:分析复方五仁醇胶囊大鼠灌胃后消化吸收进入血液的木脂素类成分,以便与该制剂血清药理学研究相结合,阐明其药效物质基础。方法:采用UPLC-MS/MS方法,比较复方五仁醇胶囊含药血清、体外制剂、空白血清及对照品提取离子流色谱图(EIC),并通过质谱图相关离子峰分析,确认进入血液的木脂素类成分。结果:发现制剂中存在的五味子醇甲、五味子醇乙、五味子酯甲、五味子甲素、五味子乙素5个木脂素类成分进入血液。结论:这5个木脂素类成分很可能是复方五仁醇胶囊体内直接作用物质的重要组成部分,结合血清药理学作进一步研究有助于阐明该制剂药效物质基础。  相似文献   
16.
An activity-guided fractionation of Virola sebifera Aubl. methylene chloride-soluble fraction provided novel 3,5-dihydro-2-(1'-oxo-3'-hexadecenyl)-2-cyclohexen-1-one (3), two known lignans (1, 2) and dehydro hexadecanoyl resorcinol (4). Isolation and purification were conducted with the application of column chromatography and structures were assigned by spetral analysis (1D and 2D NMR, HREIMS). Compounds 1-4 were evaluated for cytotoxic activities against human tumour cell lines UACC62 (melanoma), MCF-7 (breast), NCI 460 (lung, non-small cells), OVCAR03 (ovarian), PC-03 (prostate), HT-29 (colon), 786-0 (renal) and NCI-ADR (breast expressing phenotype multiple drugs resistance) in vitro. The new polyketide (3) showed selectivity against human OVCAR03 and NCI-ADR cell lines, ranging from 2 to 4 microg/mL.  相似文献   
17.
草胡椒属植物中木脂素类化合物主要包括断联木脂素、四氢呋喃型木脂素、二苄基丁内酯型木脂素、二苄基丁二醇型木脂素、双四氢呋喃型木脂素和环丁烷型木脂素,其生物活性包括抗肿瘤和细胞毒活性、雌激素样作用、抗炎作用、对植物源昆虫拒食活性的影响、抑制血管生成活性、抗艾滋病毒活性以及毒杀锥虫的活性等。综述了从草胡椒属植物中分离得到的木脂素类化合物及其生物活性,为该属植物的进一步开发提供参考。  相似文献   
18.
笔者对毛茛科铁线莲属植物化学成分研究进行了综述。铁线莲属植物化学成分比较复杂,化学结构类型包括三萜、黄酮、木脂素、香豆素、生物碱、挥发油、甾体、有机酸、大环化合物及酚类等,其中三萜皂苷、黄酮、木脂素是主要的结构类型。铁线莲属植物中的三萜皂苷主要为齐墩果酸型和常春藤皂苷元型,其中大部分为苷元的3位和28位均连有糖链的双糖链苷,只有少数为苷元的3位或28位接糖链的单糖链苷,有些皂苷的糖链上还有乙酰基(Ac)、咖啡酰基(CA)、异阿魏酰基(IF)、对甲氧基桂皮酰基(MC)和3,4-二甲氧基桂皮酰基(DMC)等取代基。其中的黄酮按结构类型可分为黄酮(苷)、黄酮醇(苷)、二氢黄酮(苷)、异黄酮(苷)和酮,既有氧糖苷,也有碳糖苷,其苷元主要为芹菜素、山柰酚、木犀草素和槲皮素。该属植物中的木脂素有Eupomtene型、环木脂素、单环氧木脂素、双环氧木脂素和木脂内酯。铁线莲属植物资源广泛,目前尚有必要进一步拓展其研究范围,以便更好地对其进行开发利用。  相似文献   
19.
为了研究砂炒对波棱瓜子有效成分、致腹泻以及保肝作用的影响,该实验采用HPLC分析波棱瓜子砂炒前后有效成分波棱甲素与波棱素的含量差异;以稀便率和腹泻指数评价砂炒对波棱瓜子总木脂素(total lignans, TL)致泻情况的影响;以CCl4急性肝损伤模型评价砂炒对波棱瓜子TL保肝作用的影响.HPLC分析结果显示,波棱瓜子砂炒后波棱甲素含量降低40.9%(P<0.01),波棱素含量无显著性变化.药效学结果显示,砂炒波棱瓜子TL高、中剂量组稀便率与腹泻指数显著低于同剂量生品波棱瓜子TL组(P<0.01或P<0.05);砂炒及生品波棱瓜子TL高、中剂量组均能显著抑制CCl4致肝损伤小鼠血清中ALT,AST水平的升高(P<0.01或P<0.05),但砂炒波棱瓜子TL高、中剂量组小鼠ALT,AST水平高于同剂量的生品波棱瓜子TL组(P<0.05).结果表明,砂炒可有效缓解波棱瓜子TL致泻作用,但是同时也降低了波棱瓜子TL的保肝作用.  相似文献   
20.
目的优选五味子种子中木脂素类成分提取工艺。方法紫外分光光度法测定总木脂素含量,以五味子总木脂素提取量为指标,采用L9(34)正交试验考察回流次数(1、2、3次)、回流时间(30、45、60 min)、乙醇体积分数(75%、85%、95%)、乙醇用量(4、5、6倍量)对五味子总木脂素提取量的影响。结果浓度在0.438~8.760μg/mL范围内,五味子乙素的吸光度与浓度有良好的线性关系(r=0.9928)。优选的工艺为5倍量95%乙醇,回流提取3次,每次60 min。结论优选的提取工艺稳定可行,可用于为五味子种子中木脂素类成分的提取。  相似文献   
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