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从茶叶抗病毒的研究--谈茶氨酸的生产与应用前景 总被引：13，自引：0，他引：13
最近,在“非典”流行期间,国内外专家都提到饮茶可增强抵抗力,预防传染病。据美国最新的研究显示,茶叶的这种作用可能与茶氨酸有关,哈佛医学院布考斯基博士通过在志愿者身上进行试验,证明茶氨酸能通过调节γ-δT免疫细胞,增强人体免疫系统,抵抗致病微生物如病毒、细菌和真菌的入侵,它甚至可5倍地提高人体预防疾病的抵抗力。科学家预言,茶氨酸有朝一日可能用于研制抗病药物。那么,茶氨酸有哪些特点和作用呢,这是人们关心的问题。茶氨酸(Theamine)是茶叶中含有的一种特殊的氨基酸,它是1950年日本学者酒户弥二郎首次从玉露茶(一种日本高级绿茶… 相似文献
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作为主要胺化合物的乙胺,每克干茶叶中约含有15微克分子。如所周知,乙胺是在茶根中合成,并用于茶氨酸的生物合成,而茶氨酸是茶叶的基本滋味成分,其含量约为0.5—2.0％。但是,乙胺在茶树体内的生理作用尚不清楚。Kito等和Komishi等曾报道了茶氨酸的乙胺部分能很好地结合到茶苗的儿茶素中去。但是,其结合的具体途径尚 相似文献
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茶氨酸作为茶叶中特有的氨基酸,是茶叶中有效的化学成分之一,对茶叶的品质也有着重要的影响。近年来,许多化学家和相关领域的专业人士对茶叶中的茶氨酸进行了大量的研究工作,包括茶氨酸在食品中的应用研究、茶氨酸对人体的作用研究,特别是关于茶氨酸在人体内的吸收和代谢、生理功能方面。现在茶氨酸作为食品添加剂的应用也较为广泛,当前研究表明,茶氨酸还具有多种保健功能,像消除疲劳、降低血压、补充营养等,因而可以预见的是茶氨酸在体育运动健康领域将发挥着更加重要的作用。本文将基于茶氨酸的研究现状,通过介绍茶氨酸的合成以及生理作用,分析和探讨茶氨酸对体育运动健康的促进作用。 相似文献
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随着科研水平有效提升,如今我们在对茶叶进行深入研究时,我们发现茶氨酸这一物质对抗疲劳有着重要帮助。茶氨酸是茶叶中的一种主要成分,其实质就是氨基酸类的物质,是在绿茶中所包含的物质,茶氨酸的含量直接决定了整个茶叶的具体品质。我国是绿茶大国,也是在整个绿茶生产体系中极具优势的国家,因此研究绿茶中的茶氨酸对缓解人体疲劳的作用和影响有着极其重要的价值。本文拟从运动疲劳和篮球运动员的运动疲劳入手,结合分析茶氨酸的相关功效,从而研究茶氨酸对篮球运动员抗疲劳的具体作用。 相似文献
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Textile fibers were obtained from secondary polyethylene terephtalate (PET) and its mixtures with primary PET at initial orientation of 18000–33000 %, rate of additional orientation drawing 3.5–6.5 times and temperature of thermal fixation 363–413 K. The fibers’ tensile strength was found to decrease and elongation at break to increase with the decrease of their linear density under the conditions of fibers formation. For the fibers based on polymer mixtures, the presence of oxidized fragments in the secondary PET limited the compatibility of the two polymers which resulted in deteriorated tensile properties. The linear density (4–16 dtex), tensile strength (30–50 cN/tex) and elongation at break (20–60 %) of the PET fibers obtained were close to these for the industrially produced polymer fibers. The values of the average diameter of the fibers formed and oriented under laboratory conditions allows classifying them between the fine and the coarse textile fibers which makes them suitable for the textile industry. 相似文献
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Gas-exchange characteristics of potato (Solanum tuberosum L.) canopies were determined with crop enclosures under condition of optimal water supply, during soil water depletion, and during recovery from drought-stress. The plants were grown under a rainshelter in large containers with 2-m2 surface area. Control plants received water throughout the growth period. In Expt. 1, transient drought was imposed by interrupting water supply completely for 22 days. During the 33-day period of drought treatment in Expt. 2, the stressed plants received half the amount of water that was given to the control plants (irrigations 2–3 times per week).
During soil water depletion, stomatal conductance of the canopy was reduced earlier and more than photosynthesis. This resulted in a lower internal carbon dioxide concentration in the leaves of stressed plants and a higher ratio between photosynthesis and stomatal conductance. The value of that ratio increased as soil water potential dropped.
Water-use efficiency ( ) increased during drought stress. The cultivar Bintje showed a larger ratio between photosynthesis and stomatal conductance of the canopy and a higher than cv. Saturna, both for optimal water supply and during drought stress.
Photosynthesis and conductance of the canopy started to recover immediately upon rewatering, even when relative values had declined to 20–30% during the preceding stress period. After release from stress, the leaves in the top layer of the canopy had a higher stomatal conductance in treated plants than in control plants. 相似文献
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《Journal of Crop Improvement》2013,27(1):313-324
Summary Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer. 相似文献
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2017—2018年,在同安镇粮食产能区示范推广水稻病虫害绿色防控与统防统治融合技术模式,取得了显著成效。融合技术示范区比常规区减少用药2~3次,用药量减少37.6%,防治成本降低400元/hm^2;水稻产量增加12.8%,收益增加2 835元/hm^2。 相似文献
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生物质能作物——甘薯开发利用现状及趋势 总被引：13，自引：0，他引：13
甘薯是世界上重要的粮食、饲料、工业原料及新型能源用块根作物，在我国乃至世界再生能源开发中起到重大作用，其分布地域广，适应性强，沙荒地、岗坡地均可种植。生物产量高，而且种植栽培容易。甘薯含淀粉15％～30％，晒干率20％～35％，世界各国以薯干或淀粉为原料生产乙醇有着悠久的历史。随着全球能源的日趋紧张，乙醇作为一种可再生的环保燃料．将快速步入全球成品油市场，在替代汽油供应方面起到越来越大的作用。各国正在推行或制定燃料乙醇计划，并着眼于生物燃料乙醇应用方案，认为甘薯可能是摆脱将来粮食和能源危机的“最后一张王牌”。 相似文献
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为明确春季调控措施对冬小麦生长发育和籽粒产量的影响,以冬小麦品种石新828为材料进行田间试验,4个处理分别为:起身期追全部氮肥(除基肥外,下同)并叶面喷多效唑(N1);起身期追2/3氮肥并喷多效唑+拔节期追1/3氮肥(N2);起身期追1/3氮肥+拔节期追2/3氮肥(N3);拔节期追全部氮肥(N4)。生育期间测定群体和个体生育特性,成熟期调查产量性状。结果表明,N1和N2处理小麦拔节期的总茎数、叶面积指数(LAI)和干物质积累量均显著高于N4和N3处理。孕穗期N4和N3处理小麦的总茎数、LAI和干物质积累量显著高于N1和N2处理。开花到成熟期各处理的总茎数、LAI和干物质积累量差异均不显著。孕穗期前,不同处理的株高差异不显著,孕穗期后,N4处理的株高最高,且显著高于N1处理。各处理基部节间直径和中上部节间长的差异不显著,N4处理基部第一节间长度显著大于其他处理。随追氮时期前移或前期施氮量增多,不孕小穗数减少,结实小穗和穗粒数增加,N1比N4处理不孕小穗数显著减少,结实小穗和穗粒数显著增多。N1处理小麦成熟期的千粒重最高,且显著高于N4处理。N1处理的籽粒产量最高,且显著高于N3和N4处理。起身期追氮配合多效唑调控,可以获得比拔节期追氮更高的穗粒数和千粒重,从而获得更高的产量。 相似文献
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施镁量和施镁方法对烤烟生长发育和烟叶产量的影响 总被引：4，自引：0，他引：4
采用盆栽试验，研究施镁量和施镁方法对烤烟生长发育和烟叶产量的影响，结果表明：适量施用镁肥，可以促进烟草的生长发育、改善其农艺学性状，影响烟株对其它营养元素的吸收与积累，提高烟叶产量，并能使烟叶N，P，K，Ca等营养元素含量更趋协调。随着施镁量的增加，烟叶中镁含量提高10．7％～71．4％，烤烟单株吸镁量、叶片叶绿素含量、干物质产量分别提高17．6％～115．4％，1．9％～23．ooA和6．3％～25．7％，而对烟叶含钾量没有明显影响。在镁比较缺乏的土壤上，镁肥作基肥施比叶面喷施的效果好，基肥施镁结合叶面喷镁的效果最佳；叶面喷镁，肥料用量少、成本低、见效快，是一种有效的镁肥施用方法；提高镁肥用量，施镁的效果更加显著。 相似文献