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1.
Summary Catkin buds of Salix alaxensis from interior Alaska were analyzed for water and lipid content and fatty acid composition throughout the year. Water content was significantly correlated with environmental temperature, but lipid content was not. Linoleic acid (18:2) and arachidic acid (20:0) were predominant in the lipids of whole catkins.Of the 27 different fatty acids found in all weekly samples, 11 showed pronounced seasonal variation, most of which occurred during catkin development and flowering in spring. During winter, only the amount of linoleic acid in the catkins was significantly negatively correlated with change in ambient temperature.Histological and chemical analyses of the catkin florets and catkin scales revealed that 99% of the linoleic acid was located in the florets primarily in the form of triglycerides while 94% of the arachidic acid was located in the catkin scale primarily as wax esters. While the linoleic acid in the triglycerides of the meristematic florets probably provides an energy source for the developing catkins, the large amounts of arachidic acid located in the catkin scales probably serves to prevent dessication of the catkins during the long, cold and dry arctic winters.  相似文献   

2.
Summary Using a pH signature criterion, it was found that whereas electrostatic attractions and repulsions were paramount in the binding of low molecular weight acid and basic dyes to tissue sections, high molecular weight dyes were also bound non-electrostatically.By studying the effects on staining of adding to aqueous dyebaths agents destroying the iceberg structure of water, the importance of hydrophobic bonding was established. It was noticed that the hydrophobic elastic fibres were stained by large dyes from dyebaths inhibitory both to electrostatic attractions and hydrophobic bonding (i.e. using acid dyes from alkaline aqueous-ethanol or aqueous-dimethylformamide dyebaths). This indicated that strong van der Waals attractions occurred, at least with some substrates. Supporting this idea was the observation that in tissue sections benzoylated before staining (i.e. made less acidophilic but more hydrophobic) additional structures were stained when using large acid dyes from alkaline aqueous-ethanol or aqueous-dimethylformamide dyebaths.Applications of the size-substantivity relationship were suggested, e.g. commenting on a standard stain for basic proteins; explaining the modes of action of traditional stains for elastic fibres and amyloid; rationalising the varied substantivities of tetrazolium salts; and finally suggesting guide lines for use in the design of new staining methods.  相似文献   

3.
The glucosylceramide components were characterized in the 33 species of the grass family (Poaceae). Pooideae contained 4-hydroxy-8-sphingenines [i.e., t18:1(8Z) plus t18:1(8E)] as major components, the relative levels of t18:1(8Z) being higher than those of the 8-E isomers. 2-Hydroxy arachidic acid was a major component in all species other than Pooideae, whereas Pooideae had a high content of 2-hydroxytetracosenoic acid.  相似文献   

4.
X-Ray diffraction was used to characterize the profile structures of ultrathin lipid multilayers having a bound surface layer of cytochrome c. The lipid multilayers were formed on an alkylated glass surface, using the Langmuir-Blodgett method. The ultrathin lipid multilayers of this study were: five monolayers of arachidic acid, four monolayers of arachidic acid with a surface monolayer of dimyristoyl phosphatidylserine, and four monolayers of arachidic acid acid with a surface monolayer of thioethyl stearate. Both the phosphatidylserine and the thioethyl stearate surfaces were found previously to covalently bind yeast cytochrome c, while the arachidic acid surface electrostatically binds yeast cytochrome c. Meridional x-ray diffraction data were collected from these lipid multilayer films with and without a bound yeast cytochrome c surface layer. A box refinement technique, previously shown to be effective in deriving the profile structures of ultrathin multilayer lipid films with and without electrostatically bound cytochrome c, was used to determine the multilayer electron density profiles. The surface monolayer of bound cytochrome c was readily apparent upon comparison of the multilayer electron density profiles for the various pairs of ultrathin multilayer films plus/minus cytochrome c for all cases. In addition, cytochrome c binding to the multilayer surface significantly perturbs the underlying lipid monolayers.  相似文献   

5.
Synthetic dyes are extensively used in textile dyeing, paper, printing, colour photography, pharmaceutics, cosmetics and other industries. Among these, azodyes represents the largest and most versatile class of synthetic dyes. As high as 50% of the dyes are released into the environment during manufacture and usage. Traditional methods of treatment are found to be expensive and have operational problems. Biological decolourization has been investigated as a method to transform, degrade or mineralize azo dyes. In the present studies bacteria from soil from dye waste area, dye waste, sewage and dung were subjected to acclimatization with C.I. Reactive Red 195 an azo dye, in the basal nutrient media. The most promising bacterial isolate was used for further dye degradation studies. The 16s rRNA gene sequencing and biochemical characteristics revealed the isolated organism as Enterococcus faecalis strain YZ66. The strain showed 99.5% decolourization of the selected dye (Reactive Red 195–50 mg/l) within one and half hour in static anoxic condition. The optimum pH and temperature for the decolourization was 5.0 and 40°C respectively. The biodegradation was monitored by UV–Vis, FTIR, TLC and HPLC. The final products were characterized by Gas chromatography and Mass Spectrophotometry. Toxicity study demonstrated no toxicity of the biodegradation product. The results suggest that the isolated organism E. faecalis strain YZ 66 can be used as a useful tool to treat waste water containing reactive dyes.  相似文献   

6.
In this study, salt fractionated bitter gourd (Momordica charantia) peroxidase was used for the decolorization of water-insoluble disperse dyes; Disperse Red 17 and Disperse Brown 1. Effect of nine different redox mediators; bromophenol, 2,4-dichlorophenol, guaiacol, 1-hydroxybenzotriazole, m-cresol, quinol, syringaldehyde, violuric acid, and vanillin on decolorization of disperse dyes by bitter gourd peroxidase has been investigated. Among these redox mediators, 1-hydroxybenzotriazole was the most effective mediator for decolorization of both the dyes by peroxidase. Bitter gourd peroxidase (0.36 U/mL) could decolorize Disperse Red 17 maximally 90% in the presence of 0.1 mM 1-hydroxybenzotriazole while Disperse Brown 1 was decolorized 65% in the presence of 0.2 mM 1-hydroxybenzotriazole. Maximum decolorization of these dyes was obtained within 1 h of incubation at pH 3.0 and temperature 40°C. The application of such enzyme plus redox mediator systems may be extendable to other recalcitrant and water insoluble synthetic dyes using novel redox mediators and peroxidases from other new and cheaper sources.  相似文献   

7.
Azo dyes are one of the most important class of dyes, which have been widely used in industries. Because of the environmental pollution of azo dyes, many studies have been performed to study their biodegradation using bacterial systems. In present work, the AzrC of mesophilic gram-positive Bacillus sp. B29 has been considered to study its interaction with five common azo dyes (orange G, acid red 88, Sudan I, orange I, and methyl red). The molecular dynamics simulations have been employed to study the interaction between AzrC and azo dyes. The trajectory was confirmed using root mean square deviation and the root mean square fluctuation analyses. Then, the hydrogen bond and alanine scanning analyses were performed to reveal active site residues. Phe105 (A), Phe125 (B), Phe172 (B), and Pro132 (B) have been found as the most important hydrophobic residues whereas Asn104 (A), Tyr127 (B), and Asn187 (A) have key role in making hydrogen bond. The results of molecular mechanics Poisson–Boltzmann surface area and molecular mechanics generalized Born surface area calculations proved that the hydrophobic azo dyes like Acid red 88 binds more tightly to the AzrC protein. The calculated data suggested MR A 121 (B) I as a potential candidate for improving the AzrC–MR interactions.  相似文献   

8.
Abstract The changes of fatty acids in larvae of the wheat blossom midge, Sitodiplosis mosellana (Gehin) at different periods were examined by gas choromatography. There were 10–16 kinds of fatty acids, of which the predominant ingredients were palmitic (C16:0), oleic (C18:1) and linoleic (C18:2) acids which were more than 95% in total fatty acids, stearic acid (C18:0) about 2%‐3.5% and any of the others was less than 1%. The fatty acid compositions increased from mid‐May, when larvae of the wheat blossom midge left the wheat‐ears and fallen on the ground, to April of next year before pupating and emerging. No arachidic acid (C20.0) was discovered in over‐summering, over‐wintering as well as inactive over‐wintered larvae. The content of saturated fatty acids in over‐summering, overwintering as well as inactive over‐wintered larvae were less than those of in active over‐wintered larvae and wheat‐ear larvae. Therefore, changes of the arachidic acid and the proportions of saturated fatty acids/unsaturated fatty acids could be used as one of the biochemical criteria to determine the active state and the degree of diapause in larvae of the wheat blossom midge.  相似文献   

9.
Synopsis The composition of various samples of Alcian Blue* and related dyes was studied, using t.l.c. (with cellulose as adsorbent andn-butanol: acetic acid: water as developing solvent), solvent extraction and precipitation, i.r. spectroscopy and classical semimicro analysis. All the Alcian Blue samples appeared to contain the same coloured components. The Alcian Green samples were mixtures of these blue components and Alcian Yellow. All the Astra Blue samples examined were composed of the same blue constituents. Colourless components identified were boricacid, dextrin and sulphate and sometimes amounted to nearly three-quarters by weight of the crude dyes. Impurities had only a slight effect on staining with Alcian Blue in aqueous acetic acid but appreciably affected staining by the critical electrolyte concentration (C.E.C.) procedure. Dextrin as impurity raised C.E.C. limits while the inorganic salt impurities raised the C.E.C. values of some substrates and lowered those of others.  相似文献   

10.
Summary Anionic dye connective tissue procedures were performed by staining for 5 min and 24 h with (a) 0.00018m and 0.0018m solutions of 28 dyes, and 0.018m solutions of 21 dyes in saturated picric acid (SPA), and (b) 0.0018m and 0.018m solutions of 20 dyes in 1% (w/v) phosphomolybdic acid (PMA). The staining obtained with dyes in SPA was classified as selective (no cytoplasmic staining), moderately selective (traces of cytoplasmic staining) and non-selective (all other staining patterns). The staining of collagen and cytoplasm with dyes in PMA was separately classified on a scale of 1–5 (1 = no staining, 5 = maximum staining). The selectivity of the staining obtained with SPA with solutions of dyes at concentrations of 0.00018m and 0.0018m, and both staining times, was correlated (p < 0.001) with an empirical sulphonic acid constant (SAC) defined as the (number of dye sulphonic acid groups/dye molecular weight) × 103. Correlation with molecular weight was poor and was significant only when staining was performed with 0.00018m dye solutions for 24 h. The dyes were divisible into three groups: group 1 (selectivity independent, or almost independent of staining time), group 2 (selective to moderately selective when staining was performed for 5 min), and group 3 (non-selective). The SAC of the group 1 dyes differed significantly from those of the group 2 and 3 dyes. Selectivity was essentially lost at dye concentrations of 0.018m. The staining with acidic dyes (no amines or substituted amines) in PMA differed significantly (p < 0.001) from that obtained with amphoteric dyes (containing basic substituents). In general, acidic dyes stained cytoplasm. Amphoteric dyes with the exception of indigocarmine stained collagen. However, most of these dyes also stained cytoplasm. In contrast to the results obtained with dyes in SPA, selectivity correlated strongly with molecular weight and only poorly with the SAC. Staining time and dye concentration affected selectivity only when the acidic dyes were used for 5 min at concentrations of 0.0018m and 0.018m. The data obtained do not permit a clear distinction between the rate control and chemical affinity models for the mechanism of staining with anionic dyes. However, it seems possible that different groups of dyes stain by different mechanisms. Part of this work was performed by M.I., S.N., M.J. and L.M. in partial fulfilment of the requirements for the completion of Pathology 438. A partial account of this work was presented at the annual convention of the British Columbia Society of Medical Technology, Victoria, British Columbia, October 1991.  相似文献   

11.
In the present paper, we report the results of a study on the in vivo localization of 51Cr-labeled lymphocytes with an altered lipid bilayer. In vitro treatment of lymphocytes with fatty acids (arachidic and linolenic acids) modifies the relative composition of plasma membrane fatty acids. Phospholipids of the plasma membrane of lymphocytes incubated with arachidic acid show a preferential increase of fatty acids with chain length between C:12 and C:16. Cells incubated with linolenic acid show an increase percentage of fatty acids C:16 to C:20 and the relative amount of the fatty acids with chain length superior to C:20 is higher in cells treated with linolenic than with arachidic acid. We have found that these alterations in plasma membrane fatty acid composition can modify the normal pattern of lymphocyte localization in vivo after iv transfer into syngeneic hosts. The possible role of factors such as cell to cell adhesion and/or fluidity of plasma membranes in the control of lymphocyte migration are discussed.  相似文献   

12.
Bioremediation is considered a promising eco-efficient alternative for industrial wastewater treatment. Particular attention is currently being given to biological degradation of synthetic dyes and more specifically to colour removal by fungi. This work looks at the extracellular enzymatic system of strain Euc-1. Its ability to decolourize 14 xenobiotic azo dyes was evaluated and compared with the well-known species Phanerochaete chrysosporium. Strain Euc-1 is a mesophilic white-rot basidiomycete, the main secreted ligninolytic enzyme being laccase (0.38 U ml–1). Although low manganese-dependent peroxidase activity (0.05 U ml–1) was also detected, neither lignin peroxidase nor aryl alcohol oxidase could be found in batch culture. Optimum pH values of 4.0 and 5.0 were obtained in the laccase-catalysed oxidation of guaiacol and syringaldazine, respectively. Laccase activity increased with the temperature rise up to 50–60 °C and remarkable thermal stability was observed at 50 °C with a half-life of 12 h and no deactivation within the first 2 h. Solid-plate decolourization studies showed that basidiomycete Euc-1 decolourized 11 azo dyes whereas P. chrysosporium only two. Moreover, it is shown that purified laccase from basidiomycete Euc-1 efficiently decolourizes the azo dye acid red 88.  相似文献   

13.
14.
Seventeen Grübler dyes produced in Germany between 1880 and 1939 were examined in this study. These dyes were: fuchsin-bacillus, diamond fuchsin, fuchsin S acid, rubin S, safranin O water soluble, safranin yellowish water soluble, methyl eosin, Sudan III, scarlet R, auramine, orange G, aniline blue, pyronin, carmine, lithium carmine, hematein and aurantia. Spectrophotometry and staining characteristics were used to determine the maximum absorbance and efficacy of each dye in common staining techniques. The spectral curves and staining characteristics of these dyes compared well with modern dyes used as controls. Fuchsin bacillus and diamond fuchsin are synonyms for basic fuchsin. Fuchsin S acid and rubin S are synonyms for acid fuchsin. The scarlet R sample was the same as the Sudan III. The two safranins were the same. The basic fuchsin samples were unsuitable for preparation of Schiff's reagent. Both basic fuchsin and pyronin samples were less concentrated than modern counterparts. It is noteworthy that the dyes worked well after up to 100 years in storage, and this observation indicates that dyes can have a long shelf life when stored in cool, dry, air-tight conditions.  相似文献   

15.
Tumors induced by the wild-type strain C58 of Agrobacterium tumefaciens in hypocotyls of Ricinus communis L. were investigated structurally and functionally with respect to xylem differentiation, cuticle and stomata development, water pathway and transpiration. Clearing of tissue with lactic acid and staining with lacmoid revealed a continuation of stem xylem into differentiated bundles in the tumor. Under the influence of tumors the host xylem below the tumors increased considerably in size. Transport of negatively-charged dyes, amido black, acid fuchsin and the fluorescent pyrenetrisulfonate demonstrated a continuous water flow through the vessels from the stem into the tumor, and up to its surface. Infrared thermography and quantitative measurements of transpiration revealed that transpiration was about 15 times and 7.5 times higher at the tumor surface in comparison to host leaves and to leaves of non-infected plants, respectively. Leaf CO2 assimilation rate remained unaffected by tumorisation. Tumor growth caused disruption of the epidermis, which did not regenerate and hence no cuticle developed to protect against water loss. Stomata located at the tumor rim hypertrophied and lost their function. Tumors are thus characterised as being structurally and functionally strong pathological water sinks on their host plant.  相似文献   

16.
Halimodendrin I, a new acylated triterpene glycoside (1), was isolated and chemically characterized as 3β-O-palmitoyl-28-[3′-palmitoyl-β-d-glucopyranosyl]-olean-12-en-28-oic acid from the aerial part of Halimodendron halodendron (Fabaceae) by IR, 1D and 2D NMR, HR-ESI-MS and LR-ESI-MS experiments. In addition, seven known compounds were isolated and identified as: palmitic acid, glycerol-2-linoleneate, glycerol-1,3-dilinoleneate, ferulic acid, 3-O-methylquercetin, β-sitosterol, and β-sitosterol-3-O-β-d-glucopyranoside. Nine fatty acids were identified and quantified in the saponifiable matter of the hexane extract. These fatty acids are: myristic, n-pentadecanoic, palmitoleic, palmitic, linoleic, oleic, stearic, arachidic, and behenic acids. The volatile oil was isolated by hydrodistillation (0.013%, w/w) with unpleasant smell. Twenty-seven components were identified in the oil by GC/MS.  相似文献   

17.
Microbial treatment of environmental pollutants including dyes with white rot fungi has received wide attention as a potential alternative for conventional methods in wastewater treatment. The degradation products from dyes and mechanism underlying fungal degradation of dyes is desirable to be understood. Capillary electrophoresis coupled with mass spectrometry (CE-MS) was used in this study to determine biodegradation products of 4-[(4-hydroxyphenyl)azo]-benzenesulfonic acid, sodium salt (4HABA) and Acid Orange 7 (C.I. 15510), produced by a white rot fungus, Pleurotus ostreatus. Two major degradation products, benzenesulfonic acid and 4-hydroxy-benzenesulfonic acid, from both sulfonated compounds, were identified and their kinetic profiles in biodegradation were followed by CE-MS. Another product, 1,2-naphthoquinone, from Acid Orange 7 was identified using HPLC. Formation of these products in fungal degradation is discussed.Revisions requested 8 October 2004; Revision received 12 November 2004  相似文献   

18.
Chitosan (CTS) is a good adsorbent for dyes but lacks the ability to adsorb cationic dyes. In this study, chitosan was modified to possess the ability to adsorb cationic dyes from water. Four kinds of phenol derivatives: 4-hydroxybenzoic acid (BA), 3,4-dihydroxybenzoic acid (DBA), 3,4-dihydroxyphenyl-acetic acid (PA), hydrocaffeic acid (CA) were used individually as substrates of tyrosinase to graft onto chitosan. FTIR analysis provided supporting evidence of phenol derivatives being grafted. The grafting amounts of these phenol derivatives onto chitosan were examined by the adsorption of an anionic dye (amaranth) and reached a plateau value. The final contents of carboxyl groups in chitosan (mmol carboxyl groups per kg chitosan) were measured as 46.36 for BA, 70.32 for DBA, 106.44 for PA, and 113.15 for CA. These modified chitosans were used in experiments on uptake of the cationic dyes crystal violet (CV) and bismarck brown Y (BB) by a batch adsorption technique at pH 7 for CV and at pH 9 for BB and 30 degrees C. Langmuir type adsorption was found, and the maximum adsorption capacities for both dyes were increased with the following order CTS-CA>CTS-PA>CTS-DBA>CTS-BA.  相似文献   

19.
The refunctionalization of a series of four well‐known industrial laser dyes, based on benzophenoxazine, is explored with the prospect of molecularly engineering new chromophores for dye‐sensitized solar cell (DSC) applications. Such engineering is important since a lack of suitable dyes is stifling the progress of DSC technology. The conceptual idea involves making laser dyes DSC‐active by chemical modification, while maintaining their key property attributes that are attractive to DSC applications. This molecular engineering follows a stepwise approach. First, molecular structures and optical absorption properties are determined for the parent laser dyes: Cresyl Violet ( 1 ), Oxazine 170 ( 2 ), Nile Blue A ( 3 ), Oxazine 750 ( 4 ). These reveal structure‐property relationships which define the prerequisites for computational molecular design of DSC dyes; the nature of their molecular architecture (D‐π‐A) and intramolecular charge transfer. Second, new DSC dyes are computationally designed by the in silico addition of a carboxylic acid anchor at various chemical substitution points in the parent laser dyes. A comparison of the resulting frontier molecular orbital energy levels with the conduction band edge of a TiO2 DSC photoanode and the redox potential of two electrolyte options I?/I3? and Co(II/III)tris(bipyridyl) suggests promise for these computationally designed dyes as co‐sensitizers for DSC applications.  相似文献   

20.
Many fungi (particularly the white rot) are well suited for treatment of a broad range of textile dye effluents due to the versatility of the lignin-degrading enzymes produced by them. We have investigated decolourization of a number of recalcitrant reactive azo and acid dyes using the culture filtrate and purified laccase from the fungus Cyathus bulleri. For this, the enzyme was purified from the culture filtrate to a high specific activity of 4,022 IU mg−1 protein, produced under optimized carbon, nitrogen and C/N ratio with induction by 2,6-dimethylaniline. The protein was characterized as a monomer of 58±5.0 kDa with carbohydrate content of 16% and was found to contain all three Cu(II) centres. The three internal peptide sequences showed sequence identity (80–92%) with laccases of a number of white rot fungi. Substrate specificity indicated highest catalytic efficiency (k cat/K M) on guaiacol followed by 2,2′-azino-bis(3-ethylthiazoline-6-sulfonic acid) (ABTS). Decolourization of a number of reactive azo and acid dyes was seen with the culture filtrate of the fungus containing predominantly laccase. In spite of no observable effect of purified laccase on other dyes, the ability to decolourize these was achieved in the presence of the redox mediator ABTS, with 50% decolourization in 0.5–5.4 days.  相似文献   

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