共查询到19条相似文献,搜索用时 468 毫秒
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由石碧、狄莹合著的《植物多酚》是国内有关植物多酚这一重要的天然产物的最新的综论性专著。内容除绪论外共分 4章 :(1 )植物多酚化学 ;(2 )植物多酚的性质 ;(3 )植物多酚的应用及其原理 ;(4 )植物多酚研究领域的几个前沿性问题。每章后附参考文献。该书获国家科学技术学术著作出版基金资助 ,由科学出版社于 2 0 0 0年 7月出版 ,1 6开精装本 ,48万字 ,每本定价 48元 ,各地新华书店均有售。该书从植物多酚的化学结构出发 ,论述其化学、物理及生物化学性质。重点阐述这类化合物与蛋白质的反应、对微生物的抑制、与金属离子的作用、抗氧化、捕… 相似文献
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从普遍存在的绿原酸到分子量在500—20000范围之间的多酚组分(即植物单宁)植物多酚的变化是很复杂的。从广义上讲,多酚主要可分为两类,即原花色素和以倍酸和(或)六羟基联苯甲酸和它们的衍生物为基础的聚酯化合物。如早期文献报道的,前者相当于凝缩类单宁,而后者则是水解单宁。作为植物的二次代谢物它们具有一些不同的分子特性。它们不仅具有多种多样酚基,而且还有一种和各种天然大分子即蛋白、多糖和核酸以及代谢物如生物碱结合成可逆复合物的倾向。根据这些性质,历史上按“伞”命名法称之为植物单宁。文中还讨论了植物多酚结构的变化因素,以及它们与其它物质的结合。 相似文献
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[目的 ]研究金花茶组植物花朵及不同花器官中多酚组分的组成和含量,为多酚组分在金花茶植物分类中的应用提供参考。[方法 ]利用HPLC方法测定金花茶组22种植物全开期花朵的花瓣、雄蕊、萼片3类器官中9种多酚组分含量,并利用聚类分析方法解析其与金花茶组植物分类的关系。[结果 ]在所测的9种多酚组分中,GCG、ECG、CG在全部样品中均检测到,而GA、GC、EGC、C、EC、EGCG在不等数量的样品中未被检测到。多酚含量最高的组分为EC,其次是EGC、GCG和ECG,剩余5种组分含量很低,前4种组分是花朵多酚总量的主要成分。在3类器官中,多酚总量及EGC、C、EC、EGCG、GCG、ECG 6种组分含量的排序为:萼片>雄蕊>花瓣;CG组分含量的排序为:花瓣>雄蕊>萼片;GA和GC组分含量的排序为:雄蕊>萼片>花瓣。聚类分析发现,雄蕊多酚组分聚类结果与各分类系统的相似率最高,达80.00%~90.00%,萼片多酚分类结果相似率为75.00%~88.89%,花瓣多酚分类结果相似率为58.33%~81.82%。[结论 ]金花茶花朵中多酚组分含量最高的为EC,主要... 相似文献
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通过对生长于额济纳旗(极端干旱区)的特征植物多枝柽柳的枝条和根系中的植物多酚含量的研究发现:柽柳根系中的缩合单宁含量明显高于枝条中的含量,而且其含量在不同径级的根系中也有较大的差别,含量随着径级的增加而减少;就总酚含量来说,中根(Ф2—10mm)部分的含量较高,其它部位的含量接近。更为重要的是,植物体内的多酚含量与其土壤中的水分含量的相关性较强,表现为多酚含量与土壤中含水量呈现出较为明显的负相关,这一点在多枝柳的根系中表现得最为明显。我们推测,植物多酚在植物抵抗水分胁迫过程中起着关键性的作用,对植物维持其体内的正常生理活动起着至关重要的作用。 相似文献
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Takashi Kunito Yoshinori Akagi Ho-Dong Park Hideshige Toda 《European Journal of Forest Research》2009,128(4):361-366
Increased atmospheric N deposition could suppress plant litter decomposition, due to the P limitation for soil microorganisms
in Japanese forested Andisols with a high P sorption capacity. To explore this possibility, we used a laboratory incubation
experiment to study the influence of N addition on β-d-glucosidase and polyphenol oxidase activities, which are important for cellulose and lignin degradation, respectively, in
an Andisol with larch (Larix kaempferi) leaf litter. The addition of N increased the β-d-glucosidase activity, whereas it decreased the polyphenol oxidase activity in the soil. However, the addition of both N and
P increased the polyphenol oxidase activity in the soil, suggesting the possibility of; (1) an inferior competitive ability
of polyphenol oxidase-producing microorganisms under nutrient-rich conditions and; of (2) their P limitation through competition
in the Andisol. 相似文献
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天然的植物活性物质对于人体健康状态的维持起着重要作用。类胡萝卜素、生育酚、皂苷化合物等植物活性物质的结构、性质、功能及作用机制相继被研究,它们陆续被开发利用为保健品,药品等产品。广泛存在于各种软果、坚果等植物组织中的活性组分鞣花酸是一种多酚二内酯,是没食子酸的二聚衍生物,具有抗氧化、抗炎、抗增殖、抗病毒等多种生物学效应,在癌症治疗和化学预防方面具有强大潜力。随着相关研究的深入,鞣花酸的作用机制和药用价值不断被挖掘,它将在疾病治疗、美容保健等方面表现出积极作用。对近几年鞣花酸的相关研究进展进行了阐述,以期为鞣花酸的后续研究提供参考。 相似文献
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D. E. Bland 《Wood Science and Technology》1971,5(1):17-26
Summary Specimens of Eucalyptus delegatensis timber showing different degrees of shrinkage and recovery on reconditioning have been examined by staining and analysed for lignin and polyphenol content. Collapsed specimens did not stain normally for lignin but this was shown to be caused by masking of staining reactions by polyphenol. Cross sectional area shrinkage before reconditioning did not show any significant correlation with either lignin or polyphenol content but shrinkage after reconditioning showed highly significant negative correlation with lignin and polyphenol content. Amount of recovery showed positive correlation with both lignin and polyphenol content. It is clear that low lignin and low polyphenol content is associated with lack of recovery and that polyphenol does tend to promote recovery. No evidence could be found to support the hypothesis that the rheological properties of the collapse specimens were influenced by esterification of the lignin with extraneous substances causing blocking of the normal lignin-polysaccharide bonding. The evidence suggests that polyphenol acts only as a bulking agent. 相似文献
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The effects of understory plant litter on dominant tree litter decomposition are not well documented especially in semi-arid forests. In this study, we used a microcosm experiment to examine the effects of two understory species (Artemisia scoparia and Setaria viridis) litter on the mass loss and N release of Mongolian pine (Pinus sylvestris var. mongolica) litter in Keerqin Sandy Lands, northeast China, and identified the influencing mechanism from the chemical quality of decomposing litter. Four litter combinations were set up: one monoculture of Mongolian pine and three mixtures of Mongolian pine and one or two understory species in equal mass proportions of each species. Total C, total N, lignin, cellulose and polyphenol concentrations, and mass loss of pine litter were analyzed at days 84 and 182 of incubation. The chemistry of pine litter not only changed with the stages of decomposition, but was also strongly influenced by the presence of understory species during decomposition. Both understory species promoted mass loss of pine litter at 84 days, while only the simultaneous presence of two understory species promoted mass loss of pine litter at 182 days. Mass loss of pine litter was negatively correlated with initial ratios of C/N, lignin/N and polyphenol/N of litter combinations during the entire incubation period; at 182 days it was negatively correlated with polyphenol concentration and ratios of C/N and polyphenol/N of litter combinations at 84 days of incubation. Nitrogen release of pine litter was promoted in the presence of understory species. Nitrogen release at 84 days was negatively correlated with initial N concentration; at 182 days it was negatively correlated with initial polyphenol concentration of litter combinations and positively correlated with lignin concentration of litter combinations at 84 days of incubation. Our results suggest that the presence of understory species causes substantial changes in chemical components of pine litter that can exert strong influences on subsequent decomposition of pine litter. 相似文献
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Assay of polyphenol oxidase activity in relation to infection with the reniform nematode, influence of reducing and oxidizing agents and the enzyme activity level inRotylenchulus reniformis- andMeloidogyne incognita-tomatoes were conducted in this study. Polyphenol oxidase activity was greater inR. reniformis-infected than in uninfected roots, but was less in tissues treated with ascorbic acid and glutathione reducing agents than in healthy or in tissues treated with copper oxychloride oxidizing agent. In uninfected roots, activity of polyphenol oxidase was nearly equal to that inR. reniformis infected tissues treated with copper oxychloride. Best plant growth was observed with copper oxychloride which was associated with the least soil and root numbers ofR. reniformis. The enzyme activity in tissues infected withR. reniformis was much higher than in those parasitized withM. incognita. This activity in either nematode infected tissue was higher than that noticed in healthy tissues. This work demonstrated the occurrence of altered metabolism uponR. reniformis infection, involvement of the oxidation-reduction physiological processes anti/pro nematode buildup as well as the detection of noticeable differences in polyphenol oxidase activity whenR. reniformis orm. incognita was present. 相似文献
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Akiko Sasaki Shozo Shikenya Kazuhiko Takeda Takayuki Nakatsubo 《Journal of Forest Research》2007,12(1):68-74
To estimate the importance of leaching of dissolved organic matter (DOM) as a pathway through which organic matter is supplied
to stream ecosystems, we examined the amount of leachate over time and chemical properties of DOM leached from leaves in different
conditions. The samples used were green leaves, yellow senescent leaves, and leaf litter of Salix gracilistyla Miq., which is the dominant riparian plant species in the middle reaches of rivers in western Japan. We analyzed dissolved
organic carbon (DOC), total sugar, and polyphenol in the leachate of leaf samples collected from a fluvial bar in the middle
reaches of the Ohtagawa River in Hiroshima Prefecture, Japan. Considerable leaching of DOC from senescent leaves [37.3 mg g−1 dry weight (dw) leaf] and leaf litter (8.1 mg g−1 dw leaf) occurred within 24 h after immersion. In contrast, DOC leached from green leaves was negligible until 1 week after
leaf immersion. Carbon loss of leaves by leaching within 24 h after leaf immersion was estimated to be less than 8%, suggesting
that leaching of DOC from S. gracilistyla leaves is a minor pathway through which organic matter is supplied to stream ecosystems. DOM leached from the leaves included
sugar and polyphenol, which were among the major chemical forms of DOM leached from the leaves (based on the molecular mass).
In a laboratory experiment in which the difference in the stability of DOM between the chemical forms was examined, sugar
decomposed more rapidly than polyphenol. 相似文献
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为比较不同品种油橄榄叶果之间多酚含量的差异,以云南引种的16个品种油橄榄叶样及13个品种的果渣样为原料,采用4因素3水平正交试验设计,选出微波辅助提取油橄榄多酚物质最优水平组合为:萃取功率为600 W、萃取时间为20 min、萃取温度为120℃、乙醇-水溶液浓度为40%,以此为微波萃取工艺条件,提取油橄榄叶样及果渣样中多酚物质,并测其含量。结果表明,叶样多酚含量鄂植8号中的最低,为1.02%,城固53中最高,为8.29%;果渣样品中多酚含量,阿斯最低,为0.64%,而莱星最高,为1.56%,油橄榄叶样中多酚含量平均值(4.21%)大于果渣中多酚平均含量(1.10%)。实验结果为从油橄榄中获取天然抗氧化剂,以延伸油橄榄产业链提供理论依据。 相似文献