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植物多酚的定量分析方法和生态作用研究进展 总被引:15,自引:0,他引:15
植物多酚是植物体内最重要的次生代谢物质.由于其特殊的结构特征和生物学活性,植物体中多酚潜在的生态学意义受到广泛关注.本文综述了植物多酚在生态领域的研究进展,并对其未来的研究方向进行了展望和预测;通过分析各种植物多酚的定性定量方法的优缺点,试图为研究植物多酚的非化学专业研究人员提供一些简单通用的分析方法. 相似文献
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植物多酚对人体的保健作用已引起人们的广泛关注.大豆异黄酮和白藜芦醇是两类重要的多酚物质.综述了大豆异黄酮和白藜芦醇的研究进展,重点阐述了大豆异黄酮合成酶基因和白藜芦醇合成酶基因的遗传转化,并对该领域今后的研究做了展望,为通过基因工程调控植物多酚的合成提供了新思路. 相似文献
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烟草中多酚氧化酶(PPO)的特征 总被引:3,自引:0,他引:3
烟草中的多酚氧化酶介导的褐变会影响烟叶和烟丝的色泽和内在质量,因此对其特性的研究,以及活性的控制成为多年来的研究热点。本文从其生物发生模型、分子结构、生物化学和光谱学特征与植物抗病和机械损伤的关系,多酚氧化酶的抑制、多酚氧化酶的应用等方面着手,对近几年来烟草中PPO研究的最新成果进行总结和回顾,对一些有争议的问题进行了探讨,并对未来PPO研究的方向和领域进行了展望。 相似文献
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综述了植物多酚的分类和来源、在代谢组学技术的驱动下,新型多酚物质的鉴定、控制植物多酚合成途径的关键因子以及多酚的功能特性的研究进展,阐述了植物多酚在肠道中的代谢以及其作为“益生元”调节肠道微生态并影响机体健康的重要功能。目前的研究表明不同植物多酚在调节肠道微生态方面存在差异,多数有促进肠道有益菌作用,并通过与肠道微生物“互作”发挥促进健康效应。总之,植物多酚作为“益生元”影响人体健康可能离不开肠道微生物的介导。各个植物多酚的益生功能也需要进一步阐析,在此过程中需要考虑宿主,膳食等混杂因素的综合影响,且需要拓展临床应用方面的研究。 相似文献
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植物多酚抗逆生态作用研究进展 总被引:6,自引:0,他引:6
植物多酚是一类重要的植物次生代谢物质,具有吸收过多的太阳辐射、过滤UV(ultra-violet)和清除体内自由基等多种生理功能,有利于传播花粉、受精及传播种子,并在植物逆境生理生态上也具有重要的作用.该文对近年来国内外有关植物多酚在逆境生态中抗生物或非生物胁迫中的作用--主要包括作为缓解营养缺乏、抵抗干旱、温度变化、盐害、大气污染、食草动物和病原菌浸染等逆境胁迫时的防御物质,以及作为植物与植物之间以及植物与环境之间信息交流物质等方面的研究进展进行综述,并展望了植物多酚的应用前景. 相似文献
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植物多酚的防癌抗癌作用 总被引:7,自引:1,他引:7
植物多酚是植物中广泛存在的一大类多酚化合物的总称,包括多酚(如单宁)、黄酮、酚酸等。体外实验研究表明植物多酚对多种人癌细胞具有增殖抑制作用,抑制动物体内肿瘤生长。其作用机理与抗氧化、调控细胞周期、诱导肿瘤细胞凋亡和分化、影响血管生成和肿瘤细胞信号传导等有关。对植物多酚的防癌抗癌作用,值得进一步深入研究。 相似文献
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植物多酚氧化酶的研究进展 总被引:1,自引:0,他引:1
多酚氧化酶(polyphenol oxidase, PPO)是一类普遍存在于植物、真菌和昆虫质体中,由核基因编码, 能与铜相结合的金属蛋白酶。它能分别催化单酚羟基和二羟基酚氧化为O-二酚和O-醌。植物多酚氧化酶是许多果蔬等农产品酶促褐变的主要原因, 同时它在植物的光合作用、抗病虫害、生长发育以及花色的形成中起一定作用。本文综述了植物多酚氧化酶在细胞学、分子遗传学及其生产应用等方面的研究进展。 相似文献
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Simonyi A Wang Q Miller RL Yusof M Shelat PB Sun AY Sun GY 《Molecular neurobiology》2005,31(1-3):135-147
Plant polyphenols are dietary components that exert a variety of biochemical and pharmacological effects. Recently, considerable
interest has been focused on polyphenols because of their antioxidant, anti-inflammatory, and antiproliferative activities.
Oxidative stress is thought to be a key event in the pathogenesis of cerebral ischemia. Overproduction of reactive oxygen
species during ischemia/reperfusion could cause an imbalance between oxidative and antioxidative processes. Reactive oxygen
species can damage lipids, proteins, and nucleic acids, thereby inducing apoptosis or necrosis. There is increasing evidence
supporting the hypothesis that plant polyphenols can provide protection against neurodegenerative changes associated with
cerebral ischemia. This article reviews the neuroprotective effects of plant extracts and their constituents that have been
used in animal models of cerebral ischemia. The use of polyphenols as therapeutic agents in stroke has been suggested. 相似文献
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V. N. Zinov’eva A. A. Spasov 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2011,5(3):231-240
Mechanisms of suppression of carcinogenesis promotion/progression by plant polyphenols have been considered. They can exhibit
antiproliferative activity by decreasing cyclins and cyclin dependent kinases and by activating their inhibitor proteins in
tumor cells. Plant polyphenols can also induce apoptosis by modulating activity of proteins involved in apoptosis and thus
exhibit proapoptotic effect. They may inhibit tumor metastasis and angiogenesis. Polyphenols act through the regulation of
cell signal transduction and gene expression and exhibit either up or down regulation of genes controlling tumor development. 相似文献
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Saleem D. Zuhra Z. Akhtar W. Koiwa H. Mahmood T. 《Russian Journal of Plant Physiology》2020,67(5):822-826
Russian Journal of Plant Physiology - Polyphenol oxidases (PPOs) are ubiquitous enzymes of plant defense which transform polyphenols into quinones that response to biotic and abiotic stresses.... 相似文献
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I. Tarascou J.M. Souquet J.P. Mazauric S. Carrillo S. Coq H. Fulcrand V. Cheynier 《Archives of biochemistry and biophysics》2010,501(1):16-22
Plant polyphenols are extremely diverse, due to the occurrence of several basic structures, numerous substitutions and, for some groups, of polymers (tannins). Plant polyphenol composition depends on the plant species and organ, with some molecules specific of particular plant families while others are ubiquitous. The polyphenol content is classically assessed by global analysis methods, which lack specificity and accuracy. These methods have been replaced with high performance liquid chromatography (HPLC), that enables accurate determination of individual molecules, provided they can be unambiguously identified and calibration curves can be established. However, HPLC analysis is restricted to simple compounds and difficult to apply in the case of complex extracts. Further difficulties encountered in the case of polymers include irreversible adsorption on the stationary phases. Proanthocyanidin analysis by HPLC after acid-catalysed depolymerisation in the presence of a nucleophile permits to overcome these problems and shows that proanthocyanidins predominate in the polyphenol composition of most plants. Large varietal differences in tannin quantitative and qualitative composition were observed for all plant species studied. Moreover, analysis is usually performed after extraction, which may lead to significant underestimation of the polyphenol content, since a large proportion is not extracted by usual solvents. This may be due to covalent binding to other plant constituents and to non-covalent adsorption on plant solids. Such matrix effect also influences the taste perception of polyphenols and their fate in the digestive tract, from in-mouth interactions with salivary proteins to their metabolism by colon microflora, with potential influence on bioavailability. 相似文献
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Morinaga N Iwamaru Y Yahiro K Tagashira M Moss J Noda M 《The Journal of biological chemistry》2005,280(24):23303-23309
Plant polyphenols, RG-tannin, and applephenon had been reported to inhibit cholera toxin (CT) ADP-ribosyltransferase activity and CT-induced fluid accumulation in mouse ileal loops. A high molecular weight fraction of hop bract extract (HBT) also inhibited CT ADP-ribosyltransferase activity. We report here the effect of those polyphenols on the binding and entry of CT into Vero cells. Binding of CT to Vero cells or to ganglioside GM1, a CT receptor, was inhibited in a concentration-dependent manner by HBT and applephenon but not RG-tannin. These observations were confirmed by fluorescence microscopy using Cy3-labeled CT. Following toxin binding to cells, applephenon, HBT, and RG-tannin suppressed its internalization. HBT or applephenon precipitated CT, CTA, and CTB from solution, creating aggregates larger than 250 kDa. In contrast, RG-tannin precipitated CT poorly; it formed complexes with CT, CTA, or CTB, which were demonstrated with sucrose density gradient centrifugation and molecular weight exclusion filters. In agreement, CTA blocked the inhibition of CT internalization by RG-tannin. These data suggest that some plant polyphenols, similar to applephenon and HBT, bind CT, forming large aggregates in solution or, perhaps, on the cell surface and thereby suppress CT binding and internalization. In contrast, RG-tannin binding to CT did not interfere with its binding to Vero cells or GM1, but it did inhibit internalization. 相似文献
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Cheruiyot EK Mumera LM Ng'etich WK Hassanali A Wachira F 《Bioscience, biotechnology, and biochemistry》2007,71(9):2190-2197
Plant polyphenols have gained prominence in quality of plant products and in human health. An experiment was conducted to determine the association of tea polyphenols with water stress and their suitability as indicators for drought tolerance. The experiment was conducted in a 'rain-out' shelter, and consisted of six tea clones (BBK 35, TRFK 6/8, TRFK 76/1, TRFK 395/2, TRFK 31/30, and TRFK 311/287) and four levels of soil water contents (38, 30, 22, and 14% v/v), which were maintained for a period of 12 weeks. The treatments were arranged in a completely randomized design and replicated three times. Plant growth was monitored over 6 weeks, and a water stress index was calculated to determine water-stress tolerant clones. Total polyphenols in tea shoots was analyzed and a regression analysis done. The results indicate that declining soil water content (SWC) reduced both growth and content of polyphenols in tea. Tolerant clones maintained a high polyphenol content at low SWC, and also showed less fluctuation in phenolics when subjected to changes in SWC. There was significant (P<0.001) correlation of total polyphenol content with shoot growth and WSI of tea, and a linear relationship (r2=0.97) between SWC for tea and both, water stress index and shoot polyphenol content. We report that there is a potential to use polyphenols as indicators for selection of drought-tolerant tea cultivars. 相似文献