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叶片中的花色素苷及其对植物适应环境的意义   总被引:30,自引:1,他引:29  
简要介绍了花色素苷的化学组成、生物合成过程和其生物合成的诱导因子,以及花色素苷对植物适应环境的意义.  相似文献   

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野生芋属植物干叶片DNA的提取及PCR扩增   总被引:1,自引:0,他引:1  
野生芋属植物体内多糖、色素、酚类等次生物质含量较高,严重影响从中提取的DNA的质量.针对这一问题,作者以6种芋属植物的干叶片为材料,摸索出一种适合芋属植物的DNA提取方法,并对提取的DNA进行了纯度鉴定和PCR检测,结果表明此方法可有效去除次生物质对DNA的干扰,样品DNA的质量和纯度较高,可用于下游分子生物学操作.  相似文献   

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通过筛选‘红富士’苹果适宜的叶面施硒浓度,研究了营养元素硒在苹果叶片中的赋存形式、分布及含硒大分子的提取分离技术。结果表明,(1)‘红富士’苹果最佳叶面施硒浓度为100mg·L-1,此处理的叶片总硒含量为2.7283mg·L-1(FW),其中有机硒含量为2.3384mg·L-1(FW),有机化程度达85.71%。(2)无论在对照组还是处理组,叶片中的有机硒均主要以蛋白质结合态存在,平均占有机硒的77.09%。(3)蛋白质、多糖和核酸3种有机物在100mg·L-1最优处理组的叶片中结合硒的量分别占有机硒含量的77.42%、18.46%和0.54%。(4)在100mg·L-1处理组的蛋白质组分中,又以盐溶性蛋白质结合硒的量最多,占蛋白质结合态硒含量的46.27%。  相似文献   

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Multiple Forms of Aminopeptidase in Euonymus Leaves   总被引:1,自引:0,他引:1  
Three different aminopeptidases (LPAase 1, LPAase 2 and APAase)separable by DEAE-cellulose column chromatography were presentin the leaves of Euonymus alatus f. ciliato-dentalus. Theseenzymes also were verified by polyacrylamide gel electrophoresis,and their substrate specificities were tested with aminoacyl-ß-naphthylamides(aminoacyl-NAs) and aminoacyl-p-nitroanilides (aminoacyl-PAs).The enzymes LPAase 1 and LPAase 2 hydrolyzed leucine-PA (LPA)and phenylalanine-NA. APAase hydrolyzed alanine-PA (APA) andarginine-NA. LPAase 1 and LPAase 2 were not affected by 1,10-phenanthroline,whereas APAase was strongly inhibited by it. All three enzymeswere inhibited by p-chloromercuribenzoate (PCMB). In the Euonymus leaves, the total activity of the three enzymes,LPAase 1, LPAase 2 and APAase, increased as leaves senescedduring autumn. The highest activity of the main enzyme, LPAase2, was found in the leaves collected during October. A markedincrease in LPAase activity was found in the red leaves collectedin December. (Received April 16, 1983; Accepted August 3, 1983)  相似文献   

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Gene resources of Oryza rufipogon Griff. play a crucial role in rice breeding, and hence to study their conservation is of utter importance. The authors describe a method for preparation of DNA from mini- amotmt of the silica-gel-dried leaves of Oryza rufipogon. The high molecular weight DNAs of 1 168 individuals representing 44 populations have been obtained with high yields, which could be used for RAPD PCR and construction of total DNA bank of this species. The template DNA from silica-gel-dried leaves stored for one year at room temperature gave the same RAPD results as that from the newly prepared silica-gel-dried leaves. The optional template DNA concentrations for amplification ranged from 3.1 ng to 50 ng. In addition, the quality and quantity of the template DNAs that affect RAPD results are also discussed.  相似文献   

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An improved method for the encapsulation of bacteria into microspheres of alginate, agarose, or polyurethane is described. Cell suspensions were passed through a low-pressure nozzle into an aqueous phase where matrix polymerization or gelation yielded beads 2 to 50 μm in diameter. Trials with a chlorophenol-degrading Flavobacterium species showed that cells entrapped by these procedures were as catabolically active as free cells. These types of beads should have numerous applications in the fields of environmental science and engineering.  相似文献   

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The Initiation and Determination of Leaves   总被引:11,自引:2,他引:9       下载免费PDF全文
Smith LG  Hake S 《The Plant cell》1992,4(9):1017-1027
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Russian Journal of Bioorganic Chemistry - The fruits of several species of the Aronia genus were studied in the content of anthocyanins and chlorogenic acids. It was found that errors in...  相似文献   

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 为探索一条研制猪血红蛋白 (pHb)为基础的血液代用品新途径 ,开发了干膜超声法将猪血红蛋白和别构效应剂、超氧化物歧化酶等联合包埋于脂质体的技术 .考察了氢化大豆卵磷脂、二肉豆蔻酰磷脂酰胆碱、胆固醇、二硬脂酰磷脂酰乙醇胺 甲氧基聚乙二醇和维生素E等在制备脂质体包埋血红蛋白 (LEH)中的作用 .通过控制磷脂与其他成分的配比 ,制得包埋率为 10 3%,pHb浓度达 16 %的稳定的LEH ;进一步将pHb微囊通过小鼠尾静脉多次注入其体内 ,检测受试小鼠血液中红细胞和白细胞数、抗体滴度、血小板聚集率及肾脏组织学等方面的变化 .小鼠体内试验表明了所制备的LEH具有低免疫原性、对肾脏无明显损害等特点 .脂质体包埋pHb是一种极具开发前景的稳定的人工载氧系统  相似文献   

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Background

Although the Newcastle disease virus (NDV) inactivated vaccines and attenuated live vaccines have been used to prevent and control Newcastle disease (ND) for years, there are some disadvantages. Recently, newly developed DNA vaccines have the potential to overcome these disadvantages. The low delivery efficiency, however, hindered the application of DNA vaccines for ND in practice.

Methodology/Principal Findings

The eukaryotic expression plasmid pVAX1-F (o) DNA that expressed the F gene of NDV encapsulated in PLGA nanoparticles (pFNDV-PLGA-NPs) were prepared by a double emulsion-solvent evaporation method and optimal preparation conditions of the pFNDV-PLGA-NPs were determined. Under the optimal conditions, the pFNDV-PLGA-NPs were produced in good morphology and had high stability with a mean diameter of 433.5±7.5 nm, with encapsulation efficiency of 91.8±0.3% and a Zeta potential of +2.7 mV. Release assay in vitro showed that the fusion gene plasmid DNA could be sustainably released from the pFNDV-PLGA-NPs up to 93.14% of the total amount. Cell transfection test indicated that the vaccine expressed and maintained its bioactivity. Immunization results showed that better immune responses of SPF chickens immunized with the pFNDV-PLGA-NPs were induced compared to the chickens immunized with the DNA vaccine alone. In addition, the safety of mucosal immunity delivery system of the pFNDV-PLGA-NPs was also tested in an in vitro cytotoxicity assay.

Conclusions/Significance

The pFNDV-PLGA-NPs could induce stronger cellular, humoral, and mucosal immune responses and reached the sustained release effect. These results laid a foundation for further development of vaccines and drugs in PLGA nanoparticles.  相似文献   

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A coproduct of dry-grind ethanol fermentation, corn distillers?? dried grains with solubles (DDGS) represents a low-cost feedstock with potential to integrate production of biodiesel and ethanol. Oil extracted from DDGS was converted into distillers?? grains methyl (DGME) and ethyl (DGEE) esters. Pretreatment using sulfuric acid was effective at lowering the acid value of the crude oil from 27.15 to less than 0.30?mg?KOH?g?1, thus rendering it amenable to homogenous, base-catalyzed transesterification. Measurement of fuel properties and comparison to refined corn oil methyl (RCME) and ethyl (RCEE) esters revealed that the cold flow properties and oxidative stability of DGME and DGEE were deficient relative to RCME and RCEE. In the absence of antioxidants, DGME and DGEE did not meet the oxidative stability specifications of ASTM D6751 and EN 14214. The cetane number of DGEE was below the minimum limit specified in EN 14214. DGEE exhibited more favorable cold flow properties, iodine value, and energy content than DGME. Evaluation of blends (B5 and B20) in petroleum diesel fuel revealed that antioxidants and cetane enhancers would be required to meet the specifications of the US and European diesel fuel standards. Other fuel properties of the petrodiesel blends were largely neutral with respect to alkyl ester type and conformed to the limits specified in the respective standards.  相似文献   

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Leaves of a novel strain of peas (Pisum sativum L.) were used to determine the distribution of secondary metabolites and their biosynthetic enzymes. Leaf epidermal layers in this strain are easily separated from the parenchyma. Anthocyanins and flavonol glycosides were localized in epidermal vacuoles only. Among the biosynthetic enzymes studied, phenylalanine ammonia-lyase (PAL, EC 4.3.1.5), S-adenosyl-1-methionine (SAM):caffeic acid and SAM:quercetin methyltransferases (o-dihydric phenol methyltransferase, EC 2.1.1.42) and a flavonoid 7-O-glucosyltransferase (EC 2.4.1.91) were chiefly localized in the parenchyma, whereas trans-cinnamate 4-monooxygenase (EC 1.14.13.11), hydroxycinnamate:CoA ligases (EC 6.2.1.12) and a flavonoid 3-O-glucosyltransferase (EC 2.4.1.91) were found mainly in the epidermis. Flavanone (chalcone) synthase activity was found only in the epidermis, whereas chalcone isomerase (EC 5.5.1.6) was evenly distributed in epidermal and parenchyma tissues.  相似文献   

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The stability against high intensity irradiation (red light, 700 W m2) was investigated for the chlorophyll(ide) pigments formed after photoreduction of the protochlorophyllide in dark grown leaves of wheat. Connections were found between changes in absorption spectrum in vivo (the Shibata shift and the late red-shift) and changes in photostability both in young (five-day) and old (12-day) leaves. The photostability of both the 684-form and the 673-form as well as the rate of the changes in photostability (the Shibata shift and the late red-shift) decreased with the age of the dark grown plants. It was concluded that the more pronounced decrease in the chlorophyll(ide) contents found at irradiation of older dark grown leaves mostly depended on the lower rate of the changes in the photostability of the pigment in old leaves. No resynthesis of protochlorophyllide occurred before the onset of the late red-shift. The results and their connection with the lag in chlorophyll formation are discussed. This lag is more pronounced in older dark grown wheat.  相似文献   

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综述了花色苷对高等植物器官颜色的决定作用及其影响因素的研究进展。花色苷本身的呈色属性、液泡定位及其在植物器官中的非均一性分布决定了花色苷能赋予植物器官颜色。花色苷单体和聚合体分子结构及其变化的多样性,以及花色苷合成与植物生长发育阶段的相关性决定了植物器官颜色的多样性。温度、光、水和矿质通过影响花色苷在液泡中的积累量而制约植物器官色度,液泡pH、氧化剂和还原剂通过影响花色苷的分子结构变化而制约植物器官色相。同时,细胞形状也通过影响花色苷的光学属性而制约器官颜色的变化。最后,还对植物器官颜色的机理和人工改良研究进行了展望。  相似文献   

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The stability against high intensity irradiation (red light, 700 W m?2) was investigated for the chlorophyll(ide) pigments formed after the primary photoreduction of the protochlorophyll(ide) in dark grown leaves of wheat. After photoreduction, most of the chlorophyll(ide) exists in a form with an absorption maximum at 684 nm. This form is gradually transformed into a form with an absorption maximum at 673 nm (the Shibata shift). It was possible to ascribe a specific photostability to each of the pigment forms. This photostability was higher for the 673-form than for the 684-form. A red-shift in the absorption maximum following upon the Shibata shift, reflects the successive transformation of the 673-form into other pigment forms, which were quite photostable at the intensity used.  相似文献   

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