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排序方式: 共有157条查询结果,搜索用时 15 毫秒
1.
Regular moderate wine consumption is often associated with reduced morbidity and mortality from a variety of chronic diseases in which inflammation is the root cause. This review is focused on three of the numerous bioactive compounds present in wine: resveratrol, hydroxytyrosol and melatonin. Resveratrol and hydroxytyrosol are polyphenols. Melatonin, recently described in wine, is an indoleamine. Their structures, concentrations in wine, bioavailability, pharmacokinetic and health promoting properties are reviewed. Resveratrol seems to be one of the most promising compounds due to its bioactivity, with wine being the main source of resveratrol in diet. Hydroxytyrosol, which its main source in diet is olive oil has been also found in both red and white wine in considerable amounts. Melatonin has been found in wine in low amounts. However, both high bioactivity and bioavailability have been attributed to it. They show antioxidant, cardioprotective, anticancer, antidiabetic, neuroprotective and antiaging activities. However, human studies are still in the initial stages and therefore further studies are needed. 相似文献
2.
以白藜芦醇为先导化合物,合成了白藜芦醇丙烯酸酯,以获得具有更好抗氧化活性的白藜芦醇衍生物。以白藜芦醇和丙烯酰氯为原料,酯化法得到白藜芦醇丙烯酸酯。以维生素C为阳性对照,研究白藜芦醇丙烯酸酯对2,2-联苯-1-苯基肼(DPPH)自由基的清除活性和抗氧化活性。用NMR和HRLC-MS对白藜芦醇丙烯酸酯进行了表征。目标产物白藜芦醇丙烯酸酯收率为30.2%。白藜芦醇丙烯酸酯的抗氧化活性高于白藜芦醇,但低于维生素C。合成得到了白藜芦醇丙烯酸酯,其反应路线简单易行,条件温和,产物抗氧化活性较先导化合物有所提高。 相似文献
3.
白藜芦醇生理活性作用研究进展 总被引:17,自引:0,他引:17
白藜芦醇存在于多种植物中,研究表明,它具有抗癌、抗血栓、抗过敏、降血脂、抗氧化等多方面功能,本文就其生理活性作用研究进展加以综述。 相似文献
4.
Feng‐Yao Tang Yu‐Ching Su Nai‐Chia Chen Hui‐Shan Hsieh Kaun‐Suei Chen 《Molecular nutrition & food research》2008,52(6):683-691
Metastasis is the primary cause of death from breast cancer. Cell migration and invasion play important roles in neoplastic metastasis. The insulin‐like growth factor (IGF‐1) stimulates cell migration through activation of PI‐3K/Akt signaling pathway. IGF‐1 induces the tumorigenicity of many types of cancer cells and is critical for metastatic cell spread in estrogen receptor (ER)‐negative breast‐cancer cells. Matrix metalloproteinase‐2 (MMP‐2) is a key enzyme in the degradation of extracellular matrices and its expression has been dysregulated in breast cancer invasion and metastasis. Resveratrol exhibited potential anticarcinogenic activities in several studies. However, the inhibitory effects of resveratrol on the expression of MMP‐2, migration and invasion of breast‐cancer cell have not been demonstrated yet. In the present study, we investigated the anti‐invasive mechanism of resveratrol in human breast cancer MDA‐MB 435cells. Here, we showed that IGF‐1 is a potent stimulant of the migration of ER‐negative human breast‐cancer cells. Resveratrol could inhibit IGF‐1‐mediated cell migration of MDA‐MB 435 in vitro. The inhibitory effect of resveratrol was mediated in part through the suppression of the activation of PI‐3K/Akt signaling pathway. Furthermore, IGF‐1‐mediated expression of MMP‐2 was significantly inhibited by resveratrol in concomitance with alteration of cell invasion. 相似文献
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6.
Aldo Todaro Rosa Palmeri Riccardo N. Barbagallo Pier Giorgio Pifferi Giovanni Spagna 《Food chemistry》2008
β-Glucosidase (EC 3.2.1.21) (β-G) from different sources were tested to increase the trans-resveratrol in some Sicilian wines by hydrolysing resveratrol glucoside. β-G from Aspergillus niger mould was tested as a crude and purified enzyme, and compared with the same enzyme from Saccharomyces cerevisiae yeast. Specific purification served to eliminate collateral enzyme activities so that β-G could be used simply and economically. Aspergillus niger β-G produced trans-resveratrol increases of up to 75%, with no change in physico-chemical properties and bouquet, and an increase in health and nutritional properties. S. cerevisiae β-G raised free-terpenol levels, but impaired wine colour due to anthocyanase activity. 相似文献
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8.
The purpose of this study was to investigate the implications of selected chemopreventive parameters and metabolic conversion of resveratrol in vivo. In two 8-week long feeding experiments with rats, a low-resveratrol diet containing 50 mg resveratrol per kg body weight (bw) and day and a high-resveratrol diet with 300 mg per kg bw and day were administered. For chemopreventive evaluation selected phase I and phase II enzymes of the biotransformation system, the total antioxidant activity, and the vitamin E status of the animals were determined. The level of resveratrol and its metabolites in the feces, urine, plasma, liver, and kidneys was identified and quantitated by high-performance liquid chromatography-diode array detection (HPLC-DAD) using synthesized resveratrol conjugate standards. Feeding of different dosages of resveratrol revealed no effect on the different chemopreventive parameters, except for the total antioxidant activity, which was elevated in plasma by 19% after feeding 50 mg resveratrol per kg bw and day. The formation of trans-resveratrol-3-sulfate, trans-resveratrol-4'-sulfate, trans-resveratrol-3,5-disulfate, trans-resveratrol-3,4'-disulfate, trans-resveratrol-3,4',5-trisulfate, trans-resveratrol-3-O-beta-D-glucuronide, and resveratrol aglycone was detected by HPLC analysis, depending on the biological material. Total resveratrol recovery in urine and feces of rats fed on 50 mg resveratrol per kg bw and day was 15% and 13%, respectively. For rats fed the higher dosage of 300 mg resveratrol per kg bw and day recovery was 54% and 17%, respectively. This is the first study performed with synthesized standards of relevant resveratrol conjugates. The lack of effect on the chemopreventive parameters is probably due to the formation of various resveratrol conjugates reducing its bioavailability in the rat. 相似文献
9.
大孔吸附树脂对虎杖中白藜芦醇吸附性能的研究 总被引:7,自引:0,他引:7
本文研究了多种大孔吸附树脂对白藜芦醇的吸附与脱附性能,从中选出H103树脂具有较大吸附量和解吸率。动态吸附实验研究了提取液浓度、pH、流速对H103树脂吸附量的影响,适合的上柱浓度为0.7157mg/ml,上柱液的pH为4.10,上柱液流速为2BV/h。4倍树脂床体积的80%乙醇以1BV/h的流速进行洗脱即可基本将白藜芦醇完全从H103树脂上解吸下来。 相似文献
10.
A microwave-assisted extraction system was used to extract phenolic antioxidants from peanut skins. The effects of microwave power (10%, 50%, 90% nominal), irradiation time (30, 90, 150 s) and sample mass (1.5, 2.5, 3.5 g) on total phenolic content (TPC), ORAC (oxygen radical absorbance capacity) level and resveratrol content of peanut skin extracts (PSE) were investigated. Peanut skins were extracted with 37.5 ml of 30% ethanol (EtOH) in water. A response surface method was used to estimate optimum extraction conditions, based on TPC, ORAC level and resveratrol content. The maximum predicted TPC, under the optimised conditions (90% microwave power, 30 s irradiation time and 1.5 g skins), was 143.6 mg gallic acid equivalent (GAE)/g skins. The highest ORAC value was 2789 μmol trolox equivalents (TE)/g skins, which occurred at 90% power, 150 s and 1.5 g of skins. Resveratrol was identified in PSE by LC–MS–MS analysis. 相似文献