白藜芦醇葡萄糖苷的生物合成

为研究淀粉蔗糖酶催化白藜芦醇的性质,从中度嗜热菌Deinococcus geothermalis克隆淀粉蔗糖酶基因dgas并在大肠杆菌中诱导表达,纯化淀粉蔗糖酶DGAS。经SDS-PAGE检测DGAS的分子量为73.0 kDa。以蔗糖为葡萄糖基供体,白藜芦醇为受体,DGAS催化合成2个白藜芦醇葡萄糖苷。大规模培养表达制备淀粉蔗糖酶DGAS,催化白藜芦醇进行糖基化反应,经柱层析分离纯化得到2个化合物1和2。经NMR波谱解析化合物1和2分别鉴定为白藜芦醇-4’-O-α-D-吡喃葡萄糖苷和白藜芦醇-4’-O-α-D-吡喃葡萄糖基-(1→4)-O-α-D-吡喃葡萄糖苷。在室温条件下,白藜芦醇-4’-O-α-D-吡喃葡萄糖苷在水中溶解度为2.26 mg/mL。     

Resveratrol in Peanuts

Peanuts are important dietary food source of resveratrol with potent antioxidant properties implicated in reducing risk of cancer, cardiovascular and Alzheimer's disease, and delaying aging. Resveratrol is a naturally occurring stilbene phytoalexin phenolic compound produced in response to a variety of biotic and abiotic stresses. This paper is a review of trans-resveratrol and related stilbenes from peanuts—their chemical structures, mechanisms for their biosynthesis, and concentrations in comparison with other major food sources. It will also discuss trans-resveratrol's absorption, bioavailability, and major health benefits; processes to enhance their biosynthesis in peanuts by biotic and abiotic stresses; process optimization for enhanced levels in peanuts and their potential food applications; and methods used for its extraction and analysis.     

Bioactivity of Resveratrol

ABSTRACT: Resveratrol (3,5,4′‐trihydroxystilbene) is a natural polyphenolic phytochemical with a variety of bioactivities associated with health promotion. Resveratrol is readily absorbed with the other absorbable digestion products of its main human dietary sources (peanuts, peanut butter, grapes, and red wine). The polyphenolic structure of resveratrol confers antioxidant activity and may reduce oxidant‐induced apoptosis and low‐density lipoprotein (LDL) oxidation. Resveratrol may be responsible, in part, for the correlation between increased wine consumption and decreased risk of coronary heart disease. The cardioprotective activity of resveratrol is associated with the inhibition of platelet aggregation and LDL oxidation and the promotion of artery vasorelaxation. As a chemoprevention agent, resveratrol has been shown to inhibit tumor initiation, promotion, and progression, as well as inhibit the growth of cancerous cells through increased apoptosis and/or cell cycle blockage. Inflammatory processes are associated in the pathogenesis of many chronic diseases including heart disease and cancer. Resveratrol has been shown to reduce inflammation via inhibition of prostaglandin production, cyclooxygenase‐2 activity, and nuclear factor‐кB activity. In addition, the estrogenic activity of resveratrol may help prevent post‐menopausal bone loss. Modulation of cellular signal transduction pathways (such as mitogen‐activated protein kinases) may explain, in part, the diverse bioactivities associated with resveratrol. Scientific information summarized in this review supports the many potential health benefits of resveratrol; however, further understanding of the bioavailability, metabolism, and cellular effects of resveratrol is necessary.     

葡萄酒中的白藜芦醇

介绍了葡萄酒中白黎芦醇的保健功能和机理、影响葡萄酒白藜芦醇含量的因素、葡萄酒中白藜芦醉的含量、以及葡萄酒中白藜芦醇含量的检测方法等。     

Resveratrol as an anti-cancer agent: A review

Owing to their antimicrobial, antioxidant, and anti-inflammatory activity, grapes (Vitis vinifera L.) are the archetypal paradigms of fruits used not only for nutritional purposes, but also for exclusive therapeutics. Grapes are a prominent and promising source of phytochemicals, especially resveratrol, a phytoalexin antioxidant found in red grapes which has both chemopreventive and therapeutic effects against various ailments. Resveratrol's role in reducing different human cancers, including breast, cervical, uterine, blood, kidney, liver, eye, bladder, thyroid, esophageal, prostate, brain, lung, skin, gastric, colon, head and neck, bone, ovarian, and cervical, has been reviewed. This review covers the literature that deals with the anti-cancer mechanism of resveratrol with special reference to antioxidant potential. Furthermore, this article summarizes the literature pertaining to resveratrol as an anti-cancer agent.     

Resveratrol: an original mechanism on tyrosinase inhibition

This paper forms part of studies searching for new bioactive ingredients for cosmetics, for example, in the whitening agent field. The aim of our work was to present resveratrol as an original substrate for tyrosinase with very promising cosmetic perspectives. This study was based on several spectrophotometric analyses with minor adaptations. These analyses suggested that resveratrol is biotransformed by tyrosinase into an oxydated form, becoming a powerful inhibitor of tyrosinase. Furthermore, we show that resveratrol can be used as an additive compound in whitening cosmetics, particularly with a Morus alba extract. These results may help in understanding tyrosinase active site structure and mechanism.     

Resveratrol and breast cancer chemoprevention: molecular mechanisms

Despite years of intensive research, breast cancer remains a major cause of death among women. New strategies to combat breast cancer are being developed, one of the most exciting of which is the use of chemopreventive agents. Resveratrol (RES) is a polyphenolic compound found in plants that seems to have a wide spectrum of biological activity. RES has been shown to afford protection against several types of cancer. This review summarizes the chemopreventive effects of RES at the three major stages of breast carcinogenesis: initiation, promotion, and progression. It has anti-oxidant and anti-inflammatory properties, and may induce apoptosis as well as modulate cell cycle and estrogen receptor function in breast cancer cell lines. Although RES has shown remarkable promise as a potent chemopreventive agent in breast cancer, further studies are needed to etablish its usefulness.     

白藜芦醇的研究进展

长期以来,法国人与西方其他发达国家居民一样以“高蛋白、高脂肪、高热量”的三高食品为主食,但法国人冠心病、高血脂等心血管疾病的发病率远低于其他饮食习惯类似的国家。据研究,这主要是因为法国人嗜好葡萄酒,其人均葡萄酒饮用量居世界首位。而葡萄酒中含有许多天然多羟基类化合物,这些化合物中除了类黄酮外,还含有丰富的对人体健康有益的白藜芦醇。1940年,人们首次从毛叶藜醇(Veratrumguandiforum)的根部得到白藜芦醇。经不断研究发现,目前至少在21个科,31个属的72种植物中含有白藜芦醇,如葡萄科的葡萄属,豆科的落花生属,百合科的藜芦属…     

Resveratrol: preventing properties against vascular alterations and ageing

Cardiovascular diseases are the leading cause of death in developed countries where the common pathological substrate underlying this process is atherosclerosis. Several new concepts have emerged in relation to mechanisms that contribute to the regulation of the vascular diseases and associated inflammatory effects. Recently, potential antioxidants (vitamin E, polyphenols) have received much attention as potential anti-atherosclerotic agents. Among the polyphenols with health benefic properties, resveratrol, a phytoalexin of grape, seem to be a good candidate protecting the vascular walls from oxidation, inflammation, platelet aggregation, and thrombus formation. In this review, we focus on the mechanism of resveratrol cardiovascular benefic effects. We analyze, in relation with the different steps of atherosclerotic process, the resveratrol properties at multiple levels, such as cellular signaling, enzymatic pathways, apoptosis, and gene expression. We show and discuss the relationship with reactive oxygen species, regulation of pro-inflammatory genes including cycloxygenases and cytokines in molecular inflammatory and aging processes, and how the regulation of these activites by resveratrol can lead to a prevention of vascular diseases.     

白藜芦醇固体脂质体制备工艺研究

采用乙醇注入法制备白藜芦醇脂质体,用冷冻干燥技术制备固体脂质体。以包封率为考察指标,对芯材与壁材的配比、乳化剂的种类和用量、冻干保护剂甘露醇使用量、油水相之比分别进行单因素考察。结果表明：最优制备工艺条件为m(卵磷脂):m(胆固醇):m(白藜芦醇)=10:2:1、乳化剂Tween 80、乳化剂用量0.2%(m/m)、冻干保护剂甘露醇使用量2%(m/m)、油水相体积比为1:10。最优工艺制得的白藜芦醇固体脂质体的包封率为84.68%,采用乙醇注入法可制得包封率高的白藜芦醇固体脂质体,且方法简便易行。     

白藜芦醇及其药理保健功能的研究

白藜芦醇存在于多种植物之中 ,研究表明它具有化学防癌、保护心血管系统、雌激素样作用、影响骨代谢等多种生理活性。本文综述了其基本理化性质、合成方法、分离提取、检测以及主要生理活性。     

白藜芦醇纳米传递系统的研究进展

白藜芦醇是一种天然非黄酮类多酚化合物,具有抗炎、抗自由基、抗心血管疾病、抗肿瘤等诸多药理活性.但因其水溶性差和见光易分解的性质导致其生物利用度低,限制了在食品和药品方面的应用.纳米传递系统因其具有良好的生物相容性、靶向性及缓释性等诸多优点成为极具发展潜力的新型传递系统.基于近年来白藜芦醇纳米传递系统的研究不断深入,对白...     

Taste Detection Thresholds of Resveratrol

Resveratrol is a polyphenol that is associated with numerous health benefits related to heart disease, cancer, diabetes, and neurological function. The addition of this compound to food products would help to deliver these health benefits to the consumer. However, bitterness associated with resveratrol may impart negative sensory qualities on the food products into which resveratrol is added; thus, decreasing consumer acceptability. This concern may be resolved by encapsulating resveratrol through spray drying, an innovative processing technique. The objectives of this research were to (1) compare taste detection thresholds of unencapsulated resveratrol and encapsulated resveratrol and (2) determine if the inclusion of anhydrous milk fat in the formulation of the encapsulation wall material affects the taste detection threshold of resveratrol within the microcapsules. Resveratrol microcapsules were produced by encapsulating resveratrol in a protein matrix through spray drying. R‐index measure by the rating method was used to determine the average taste detection threshold and the pooled group taste detection threshold. The average and pooled group taste detection thresholds of unencapsulated resveratrol, sodium‐caseinate‐based resveratrol microcapsule without fat (SC), and sodium‐caseinate‐based resveratrol microcapsule with fat (SCAMF) were 90 and 47 mg resveratrol/L (unencapsulated), 313 and 103 mg resveratrol/L (SC), 334 and 108 mg resveratrol/L (SCAMF), respectively. The findings demonstrate that the encapsulation of resveratrol decreased the detection of the compound and provided a means to incorporate resveratrol into food products without imparting negative sensory properties.     

白藜芦醇提取工艺的研究

本研究探讨了虎杖中白藜芦醇的提取工艺和稳定性。在虎杖中,白藜芦醇对光、干热、湿热和氧化剂均敏感;通过实验得出回流、超声、固定床连续提取的提取率分别0.201%、0.423%、0.513%;同时利用正交设计得出固定床连续提取的最佳工艺为溶剂为30%乙醇,固定床连续提取速度为8ml/min·kg,浸泡时间为12h,溶剂用量为8倍量。     

Bioactive compounds in wine: Resveratrol,hydroxytyrosol and melatonin: A review

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.     

虎杖中白藜芦醇提取工艺研究

白藜芦醇是一种重要的活性天然产物,本研究以虎杖为原料,研究了白藜芦醇的溶剂法和酶解法提取工艺,考察了料液比、提取时间、提取温度、pH、酶加入量等对提取得率的影响．通过正交实验优化了溶剂法和酶解法的最佳工艺参数．实验结果表明：溶剂法优化工艺为：pH 5,料液比1:65,提取温度是60 ℃,提取时间2 h;酶解法优化工艺为：pH 6,料液比1:40,酶解温度是60 ℃,酶解时间2 h,二者得率分别是：0.496%和0.942%。酶解法的得率大约是溶剂法的2倍,可以作为虎杖中白藜芦醇提取的优选方法。     

白藜芦醇的雌激素作用研究

目的探索反式白藜芦醇经口摄入后,在体内的雌激素作用和剂量一反应关系。方法选用19日龄未成年大鼠做子宫增重试验,分别经灌胃给予0．1、0．3、0．6和1．0g／kgBW的白藜芦醇,以3．0p∥kgBW的雌二醇为阳性对照,并设立水和油的阴性对照组,所有剂量组连续灌胃3d。实验结束称量子宫的湿重和干重,对卵巢、子宫和阴道进行组织病理学检查,并测量子宫内膜上皮细胞高度。结果和对照组比较,白藜芦醇对子宫重量无影响;组织病理学结果显示,1．0g／kgBW白藜芦醇剂量组的子宫轻度增生,0．3、0．6和1．0g／kgBW白藜芦醇剂量组的阴道轻度增生,无剂量-反应关系;受试物组子宫内膜上皮细胞高度无明显变化。结论白藜芦醇经口摄入时雌激素作用较弱,且无剂量-反应关系。