膜分离后的儿茶色素染发性能研究

本文采用聚偏氟乙烯膜提纯天然儿茶色素,结果表明膜分离法具有较好的分离效果.考察了染色温度,时间,pH值及媒染剂浓度等对白色牦牛毛染色效果的影响.结果表明,天然儿茶色素对白色牦牛毛具有直接染色效果,可染成棕色系列.锌离子可使毛发颜色偏向栗子色,铁离子和铜离子可使毛发颜色偏向黑色.其中温度与媒染剂浓度是影响颜色的重要因素.     

A review of the chemistry and uses of crocins and crocetin,the carotenoid natural dyes in saffron,with particular emphasis on applications as colorants including their use as biological stains

The perennial flowering plant, saffron crocus (Crocus sativus L.), is the source of the most expensive spice in the world. The dried stigmas of saffron flowers are the source of a natural dye, saffron, which has been used from ancient times for dyeing silk and fabric rugs, and for painting; it also has been used for cooking and in medicine. The yellow compounds present in the dye include crocins, which are 20-carbon water soluble glycosyl derivatives of the carotenoid, crocetin, and the dicarboxylic acid itself. We review the chemistry of these compounds and discuss various applications of saffron as a natural dye. We review in particular the use of saffron or its constituents in histopathologic techniques.     

Effect of microbial transglutaminase on dyeing properties of natural dyes on wool fabric

The dyeing properties of three natural dyes – curcumin, gardenia yellow and lac dye – on wool fabric after treatment with microbial transglutaminase (MTGase) have been investigated. After 120 min of MTGase treatment, compared with the fabric only pretreated with chemical and protease, the colour strength of curcumin, gardenia yellow and lac dye increased from 8±0.13, 7.5±0.10 and 22±0.12 to about 12.8±0.20, 11.7±0.20 and 27.0±0.41, respectively. The values of wash fastness for dyed wool fabrics increased from 2 to 4 after MTGase treatment, but the light fastness was not obviously improved. By comparing with mordant dyeing, although the colour strength was poorer, MTGase after-treatment did not cause colour shade changes during dyeing and the wash fastness of dyed wool fabric was similar to that of the pre-mordanted samples.     

中药诃子制备的天然染料对棉织物的染色研究

本文研究由中药诃子制备的天然染料对棉织物染色方法,分别采用非媒、预媒、同媒和后媒四种染色方法,并运用多种媒染剂进行染色试验。研究结果表明:采用优化的铝预媒染色工艺可染得色泽鲜艳,色牢度较好的黄色棉织物。     

A non-toxic fluorogenic dye for mitochondria labeling

Background

Mitochondria, powerhouses of cells, are responsible for many critical cellular functions, such as cell energy metabolism, reactive oxygen species production, and apoptosis regulation. Monitoring mitochondria morphology in live cells temporally and spatially could help with the understanding of the mechanisms of mitochondrial functional regulation and the pathogenesis of mitochondria-related diseases.

Methods

A novel non-cytotoxic fluorogenic compound, AcQCy7, was developed as a mitochondria-specific dye.

Results

AcQCy7 emitted no fluorescent signal outside of cells, but it became fluorescent after intracellular hydrolysis of the acetyl group. The hydrolyzed fluorescent product was well retained in mitochondria, enabling long-lasting fluorescence imaging of mitochondria without cell washing. A 2-day culture study using AcQCy7 showed no sign of cytotoxicity, whereas a commonly used mitochondria-staining probe, Mitochondria Tracker Green, caused significant cell death even at a much lower concentration. Apoptosis-causing mitochondria fission was monitored clearly in real time by AcQCy7.

Conclusions

A simple add-and-read mitochondria specific dye AcQCy7 has been validated in various cell models. Bright mitochondria specific fluorescent signal in treated cells lasted several days without noticeable toxicity.

General Significance

The probe AcQCy7 has been proofed to be a non-toxic agent for long-term mitochondria imaging.     

Mutation of bacterium Vibrio gazogenes for selective preparation of colorants

A novel marine bacterium strain effectively produced prodiginine type pigments. These colorants could dye wool, silk and synthetic fabrics such as polyester and polyacrylic and also show antibacterial properties against Escherichia coli and Staphylococcus aureus bacteria on the dyed products. Methyl nitrosoguanidine was used as a mutation agent to increase the genetic diversity and the production yield of the bacteria of the family of Vibrio gazogenes. The analysis of the mutated samples showed that two new main colorants as well as three previously found ones were produced. Liquid chromatography electro spray ionization mass spectrometry (LC‐ESI‐MS) and nuclear magnetic resonance (NMR) spectroscopic techniques were used to elucidate the structures of the newly produced colorants. Mass measurements revealed that the colorants C1, C2, C3, C4 have molecular masses of 321, 323, 351, and 295 Da. One unstable colorant C5 with molecular mass of 309 Da was detected as well. The mutated bacteria strains increased the yield of pigment production by about 81% and produced prodigiosin in 97% purity. The antibiotic activities of pure colorants are discussed as well. Based on their bio‐activity and excellent dyeing capabilities, these colorants could be employed in cosmetic and textile industries. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010     

Basic Blue 148: A Rapid Stain for T Helper Cells

After brief exposure to an aqueous solution of the oxazine textile dye C. I. basic blue 148 following fixation in 37% formalin, 95% ethanol and glacial acetic acid, T helper cell nuclei and cytoplasm in specimens of peripheral blood displayed a deep red-violet color. No other cell in normal blood or bone marrow specimens showed intense staining of this type. The total staining time is 1 min. Basic blue 148 stain is a promising technique for hematology and immunology laboratories as a rapid screening test for T helper cells in blood specimens using a microscopic slide and ordinary incandescent illumination.     

Impermeant potential-sensitive oxonol dyes: II. The dependence of the absorption signal on the length of alkyl substituents attached to the dye

Summary We have measured the potential-dependent light absorption changes of 43 impermeant oxonol dyes with an oxidized cholesterol bilayer lipid membrane system. The size of the signal is strongly dependent on the chain length of alkyl groups attached to the chromophore. Dye molecules with intermediate chain lengths give the largest signals. To better understand the dependence of the absorbance signal on alkyl chain length, a simple equilibrium thermodynamic analysis has been derived. The analysis uses the free energy of dye binding to the membrane and the on-off model (E.B. George et al.,J. Membrane Biol.,103:245–253, 1988a) for the potential-sensing mechanism. In this model, a population of dye molecules in nonpolar membrane binding sites is in a potential-dependent equilibrium with a second population of dye that resides in an unstirred layer adjacent to the membrane. Dye in the unstirred layer is in a separate equilibrium with dye in the bulk bathing solution. The equilibrium binding theory predicts a sigmoidally shaped increase in signal with increasing alkyl chain length, even for very nonpolar dyes. We suggest that aggregation of the more hydrophobic dyes in the membrane bathing solution may be responsible for their low signals, which are not predicted by the theory.     

Transforming Benzophenoxazine Laser Dyes into Chromophores for Dye‐Sensitized Solar Cells: A Molecular Engineering Approach

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.     

Supravital Uptake of Cationic Dyes by Mast Cell Granules: A Light and Electron Microscope Study

Methylene blue and neutral red were selected for staining mast cell granules by supravital injections. A new technique was applied for embedding in paraffin and Araldite® without dislocation or loss of dye. Stabilization and electron microscopic identification of the dyes were achieved by transforming them into electron-dense precipitates using phosphomolybdic acid dissolved in a paraformaldehyde-glutaraldehyde mixture to preserve the ultra structure of the tissues. It was found that in general the intensity of the light microscopic staining correlated directly with the electron density. Closer study revealed that not all cytoplasmic granules exhibited the same strong affinity for the cationic dyes. Furthermore, differences in dye distribution were observed within the granules themselves. The difference in the staining pattern can be explained by the heterogeneous occurrence of the anionic residues. Because of its high sensitivity and relatively low toxicity, the method described here is well suited for detecting the binding sites of organic cations in tissues under supravital or vital conditions     

A Hypochlorite-Fast Metachromatic Quick Stain for Human Megakaryocytes

Megakaryocytes in aspirates of normal and abnormal human bone marrow displayed rose-pink metachromasla when stained with a violet polymethine dye. The color of the megakaryocytes persisted when the stained sample was exposed to a dilute solution of sodium hypochlorite. Under the same conditions, other hematopoietic cells became colorless. This stain may be useful for demonstrating megakaryocyte from both healthy and diseased bone marrow specimens.     

A study on risk assessment of effect of hematoxylin dye on cytotoxicity and nephrotoxicity in freshwater fish: Food and water security prospective research

The cytotoxicity in freshwater fishes due to different industrial dyes in industrial effluents is a major worldwide issue. Hematoxylin dye has a wide range of uses in textile industries and laboratories. This study was aimed to evaluate the toxic effects of hematoxylin's sublethal effect in vitro in Cirrhinus mrigala. The fish was exposed to different grading concentrations of dye in the aquarium. Fish were sacrificed and dissected to remove the kidney after exposure to hematoxylin dye for specific time intervals. Nephrotoxicity and cytotoxicity induced by this dye were detected through histopathology by using the paraffin wax method. Immediate mortality of fish was noticed against the exposure to 0.08 g/L (LC₅₀) concentration of dye, but at 0.008 mg/L and 0.018 mg/L, it showed tremendous tissue damage in the kidneys, significant reduction in fish growth. This dye induced many alterations in the kidney such as tubular degeneration, vacuolation, shrinkage of a glomerulus, reduced lumen, congestion in the kidney, glomerulonephritis, absence of Bowmen space, necrosis of the hematopoietic interstitial tissues, clogging of tubules, necrosis in the glomerulus and increased space between glomerulus and bowmen's capsule. Although this dye has a wide range of biological and industrial applications, a minute amount of hematoxylin released in effluents is quite toxic to aquatic fauna.     

A database on natural and transgenic luminous microorganisms: BiolumBase

The database BiolumBase was designed for the collection and systematization of available information on microorganisms containing bioluminescent systems; it includes two sections: natural and transgenic luminous microorganisms. By now, logic schemes of these sections have been developed, classification of the objects has been performed, ways of presentation of characteristics and structure of fields for input of information have been elaborated, and the necessary program modules have been developed. The database is filled on the basis of published data and our own experimental results; subsequent linkage of the database to the Internet is envisaged. Users will be able to obtain not only catalogues of strains but also information concerning the properties and functions of the known species of luminous bacteria, the structure, regulatory mechanisms, and application of bioluminescent systems and genetically engineered constructions with lux genes, as well as to find references and to search strains by using any set of attributes. The database will provide information that is of interest for the development of microbial ecology and biotechnology, in particular, for the prediction of biological hazard from the application of transgenic strains.__________Translated from Mikrobiologiya, Vol. 74, No. 2, 2005, pp. 278–286.Original Russian Text Copyright © 2005 by Medvedeva, Boyandin, Lankin, Kotov, Kargatova, Rodicheva, Popova.     

Impermeant potential-sensitive oxonol dyes: III. The dependence of the absorption signal on membrane potential

Summary We have measured potential-dependent changes in the absorption of light by oxidized cholesterol bilayer lipid membranes in the presence of impermeant oxonol dyes. The magnitude of the absorption signal increased linearly with the size of potential steps over a range of 500 mV. The signal also increased when the offset voltage of the pulse train was increased from –150 to +150 mV. The data are consistent with the on-off mechanism proposed by E. B. George et al. (J. Membrane Biol.103:245–253, 1988) in which the probe undergoes potential-dependent movement between a binding site in the membrane and an aqueous region just off the surface of the membrane. An equilibrium thermodynamic analysis of the experimental data indicates that the negatively charged oxonol chromophore senses only 5–10% of the total membrane potential difference across the membrane when it is driven into a nonpolar binding site on the membrane.ASW, Carnegie-Mellon University     

A novel method for measuring human hepatic lipase activity in postheparin plasma

The objective of this study was to establish a hepatic lipase (HL) assay method that can be applied to automatic clinical analyzers. Seventy-four hyperlipidemic subjects (men/women 45/29) were recruited. Lipase activity was assayed measuring the increase in absorbance at 546 nm due to quinonediimine dye production. Reaction mixture R-1 contained 50 mM Tris-HCl (pH 9.5), 0.5 mM glycerol-1,2-dioleate, 0.4% (unless otherwise noted) polyoxyethylene-nonylphenylether, 3 mM ATP, 3 mM MgCl(2), 1.5 mM CaCl(2), monoacylglycerol-specific lipase, glycerol kinase, glycerol-3-phosphate oxidase, 0.075% N,N-bis-(4-sulfobutyl)-3-methylaniline-2 Na, peroxidase, ascorbic acid oxidase. Reaction mixture R-2 contained 50 mM Tris-HCl (pH9.5), 0.15% 4-aminoantypirine. Automated assay for activity was performed with a Model 7080 Hitachi analyzer. In the lipase assay, 160 microl of R-1 was incubated at 37 degrees C with 3 microl of samples for 5 min, and 80 microl of R-2 was added. Within-run coefficient of variations was 0.9-1.0%. Calibration curve of lipase activity was linear (r = 0.999) between 0 and 320 U/l. Analytical recoveries of purified HL added to plasma were 96.6-99.8%. HL activity in postheparin plasma measured in this method had a closer correlation with HL mass by a sandwich ELISA (r = 0.888, P < 0.0001) than those in the conventional method using [(14)C-]triolein (r = 0.730, P < 0.0001). This assay method for HL activity can be applied to an automatic clinical analyzer.     

A New Organic Dye-Based Staining for The Detection of Plant DNA in Agarose Gels

Ethidium bromide (EtBr) is used to stain DNA in agarose gel electrophoresis, but this dye is mutagenic and carcinogenic. We investigated N-719, which is a visible, reliable and organic Ruthenium-based dye, and five fluorescent alternatives for staining plant DNA. For prestaining and poststaining, N-719, GelRed, and SYBR Safe stained both DNA and PCR product bands as clearly as EtBr. SYBR Green I, methylene blue, and crystal violet were effective for poststaining only. The organic dye N-719 stained DNA bands as sensitively and as clearly as EtBr. Consequently, organic dyes can be used as alternatives to EtBr in plant biotechnology studies.