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1.
Electron spin resonance (ESR) and atomic force microscopy (AFM) were used to study liposomes that were prepared from soybean phosphatidylcholine (PC); they incorporated plant antioxidants (ginger, allspice, and black-pepper extracts; clove oil; etc.) that were encapsulated in biopolymers (sodium caseinate or sodium caseinate–maltodextrin covalent conjugates). Plant antioxidants were shown to cause a 15–25% decrease in the microviscosity of deep-lying regions of the liposome lipid bilayer by ESR with a 16-doxylstearic acid spin probe. A ginger extract exerted the greatest effect (24%). Sodium caseinate and its covalent conjugates with maltodextrins (dextrose equivalents (DEs) 2 and 10) increased the microviscosity by 30–35% as compared with free and antioxidant-incorporating liposomes. AFM showed that antioxidants increased the cross-sectional area and volume of liposomes and that the polymers made liposomes denser and their structure more compact.  相似文献   

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Moringa, belonging to Moringaceae, is known as the “Miracle Tree” that has versatile uses in both animals and plants. The extract from Moringa oliefera serves as a cheap, eco-friendly, novel biostimulator, and bioenhancer that increases sustainable agriculture practices and crop production. Moringa contains several essential components like mineral nutrients, phytohormones (e.g., auxins, gibberellins, and cytokinins), vitamins, flavonols, phenols, sterols, and tannins, as well as several phytochemicals that make it highly beneficial for plants. It induces seed germination, plant growth, photosynthesis, and yields traits at a low cost. It also increases flowering, improves floral traits, fruiting, post-harvesting, and product quality of the fruit, and decreases senescence. Abiotic stresses have a detrimental effect on plant growth and development. The application of Moringa extracts on plants mitigates abiotic stress like salinity, drought, heavy metal, and heat by promoting the activity of antioxidant enzymes and increasing the content of phenols, flavonols, sugars, and osmolyte, which reduces the level of reactive oxygen species, lipid peroxidation, and electrolyte leakage. In particular, Moringa accelerates plant growth, relative water content, water use efficiency, mineral content, gas exchange traits, and yield attributes under stressful environmental conditions. Moringa serves as an essential biopesticide against plant pathogens, and is used in disease management and plant sustenance.

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Molecular Biology - Preeclampsia (PE) is a severe hypertensive pathology and affects 2–8% of pregnancies worldwide. Its etiopathogenesis is poorly understood, and prognostic biomarkers and...  相似文献   

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Human cytomegalovirus (HCMV) has a coding capacity for glycoproteins which far exceeds that of other herpesviruses. Few of these proteins have been characterized. We have investigated the gene product(s) of reading frame 10, which is present in both the internal and terminal repeat regions of HCMV strain AD169 and only once in clinical isolates. The putative protein product is a 171-amino-acid glycoprotein with a theoretical mass of 20.5 kDa. We characterized the protein encoded by this reading frame in the laboratory strain AD169 and a recent isolate, TB40E. The results from both strains were comparable. Northern blot analyses showed that the gene was transcribed with early/late kinetics. Two proteins of 22 and 23.5-kDa were detected in virus-infected cells and in cells transiently expressing recombinant TRL10. Both forms contained only high-mannose-linked carbohydrate modifications. In addition, virus-infected cells expressed small amounts of the protein modified with complex N-linked sugars. Image analysis localized transiently expressed TRL10 to the endoplasmic reticulum. Immunoblot analyses as well as immunoelectron microscopy of purified virions demonstrated that TRL10 represents a structural component of the virus particle. Immunoblot analysis in the absence of reducing agents indicated that TRL10, like the other HCMV envelope glycoproteins, is present in a disulfide-linked complex. Sequence analysis of the TRL10 coding region in nine low-passage clinical isolates revealed strain-specific variation. In summary, the protein product of the TRL10 open reading frame represents a novel structural glycoprotein of HCMV and was termed gpTRL10.  相似文献   

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植物中存在着一种双组分信号系统,该系统由组氨酸蛋白激酶,HPt蛋白和反应调节器组成,它参与乙烯,细胞分裂素等的信号转导,并且与光敏色素信号产生有关。  相似文献   

7.
The Forgotten Component of Plant Water Potential   总被引:2,自引:0,他引:2  
Abstract: Experts in plant water relations are challenged to explain why the standard expression for the water potential of an intact, transpiring leaf omits one of the pressure components, namely the tissue pressure of the living leaf cells. Two questions are posed: A) Is there a reason for omitting this component? B) If not, what evidence exists that it may be ignored? When this component contributes significantly, the water potential cannot be interpreted in the accustomed way as measuring tension in the xylem sap.  相似文献   

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Helminthosporol was isolated as a natural plant growth-regulator produced by Helminthosporium sativum and its structure was assigned as I. Oxidation of I with chromium trioxide-pyridine complex gave helminthosporal (II). The glycol (III), obtained by the reduction of I or II, yielded I by the oxidation with activated manganese dioxide. I spontaneously changed into helminthosporic acid (IV), when the former in organic solvent was let to stand in the air.  相似文献   

9.
Telomeric repeat-containing RNA, a non-coding RNA molecule, has recently been found in mammalian cells. The detailed structural features and functions of the telomeric RNA at human chromosome ends remain unclear, although this RNA molecule may be a key component of the telomere machinery. In this study, using model human telomeric DNA and RNA sequences, we demonstrated that human telomeric RNA and DNA oligonucleotides form a DNA-RNA G-quadruplex. We next employed chemistry-based oligonucleotide probes to mimic the naturally formed telomeric DNA-RNA G-quadruplexes in living cells, suggesting that the process of DNA-RNA G-quadruplex formation with oligonucleotide models of telomeric DNA and RNA could occur in cells. Furthermore, we investigated the possible roles of this DNA-RNA G-quadruplex. The formation of the DNA-RNA G-quadruplex causes a significant increase in the clonogenic capacity of cells and has an effect on inhibition of cellular senescence. Here, we have used a model system to provide evidence about the formation of G-quadruplex structures involving telomeric DNA and RNA sequences that have the potential to provide a protective capping structure for telomere ends.  相似文献   

10.
The Cellular Basis for Colony Form in Podocoryne carnea   总被引:1,自引:0,他引:1  
During the past 10 years considerable data have appeared indicatingthat the growth of hydroids is not, as was earlier believed,similar to the meristematic growth of plants, but rather thatthe sites of cell proliferation are removed in space from thesites of utilization, that cells migrate individually, activelyas amoebocytes through the epidermis or pawively as epitheliocytescarried along in the hydroplasm, to the sites of utilization,and that considerable migration across the mesoglea occurs. A model of hydroid morphogenesis and morphostasis based on thisnew information provides a comprehensive picture, albeit onefilled in with numerous assumptions, of the manner in whichcolony form is produced as a consequence of cell proclivities.  相似文献   

11.
The replacement of synthetic foam materials using natural biological ones is of great significance for saving energy/resources and reducing environmental pollut...  相似文献   

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The geometrical surfaces of soil-burrowing animals were imitated and modeled on a cone component, the measuring tip part of a soil cone penetrometer. These biomimetic surfaces are concave dimples, convex domes and two wavy forms. The conventional cone surface and the biomimetic cone surfaces were analyzed in ANSYS 11.0 program to estimate cone equivalent stress and soil equivalent stress. Results show that biomimetic surfaces with the geometrical structures have lower cone equivalent stresses and soil equivalent stresses than that with conventional (smooth) surface. The least maximum cone equivalent stress and least maximum soil equivalent stress were recorded for biomimetic surfaces with concave dimples and wavy form-2 respectively. The two-body abrasive wear of biomimetic cone surfaces and conventional (smooth) cone surface were run on a rotary disk type of abrasive wear testing machine. The biomimetic cone surfaces were found to have lower abrasive wear than the conventional surface. It was found that and biomimetic cone surface with concave dimples has the lowest abrasive wear among the all tested surfaces.  相似文献   

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Deduction leads to causal explanation in phylogenetic inference when the evidence, the systematic character, is conceptualized as a transformation series. Also, the deductive entailment of modus tollens is satisfied when those kinds of events are operationalized as patristic difference. Arguments to the contrary are based largely on the premise that character-states are defined intensionally as objects, in terms of similarity relations. However, such relations leave biologists without epistemological access to the causal explanation and explanatory power of historical statements. Moreover, the prediction-making to which those kinds of relations are limited in practice can lead to a category error—the mental conversion of an abstraction (the classes defined in terms of similarity relations) into a thing (such as an historical individual). The latter practices and problems characterize pattern cladistics, taxa being interpreted as homeostatic property cluster natural kinds, and other instrumentalist research programs.  相似文献   

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The electron microscopic image and some properties of a filamentouscomponent of plant extracts are described. The filaments are3·5 nm in diameter, non-rigid and present a beaded appearancewhen positively stained with uranyl and lead salts. They arepresent in the microsomal supernatant fractions of a varietyof plants, and can be obtained in extracts of fresh tissuesor of acetone powder preparations. Specific tissues, successfullyextracted for filaments, include phloem, xylem and corticalparenchyma. They are not present in extracts of cell wall preparationsor of hair cells of cotton bolls. An outstanding characteristicof these filaments is their great stability to a wide varietyof treatments which includes variation in temperature, ionicenvironment, pH and the presence of urea, thiol reagents orthe detergent Nonidet. Lateral aggregation of the filamentsis evident below pH 3·0 and above pH 8·0. Althoughcellulase was the only enzyme of those tested which digestedthe filaments, it is unlikely, for several reasons, that thefilaments are a form of pure cellulose. Hydroxyproline was presentin all filament fractions after partial purification by variousmethods. The filaments are discussed in relation to known fibrillarcomponents of plant cells.  相似文献   

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