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1.
A method is described for the purification of the dye azure B in quantities sufficient for biological staining experiments on a larger scale. The method is based on the use of column chromatography. Two columns are employed. In column A with silica gel as adsorbent the azure B fraction is isolated from a suitable substrate ('technical' azure B gained by a modification of Bernthsen's synthesis of methylene blue, or plychrome methylene blue) using an acetate-formate mixture as eluent. In column B, on an Amberlite polyineric adsorbent (XAD-2) the acetate-formate anions are exchanged for chloride. Regeneration of both columns is possible: KMnO4, Na2S2O4 and water are run through column A, 5% NaOH, methanol and water through column B. Purification of azure B on economic terms is thus attained. The opinion is expressed that this method is also applicable to the purification of other cationic dyes.  相似文献   

2.
Column and paper chromatography of four thiazin dyes revealed both inorganic and organic impurities. In thionin, azure A, azure B and methylene blue, sodium and other metal cations were found as inorganic impurities. The analysis for organic impurities revealed that the dyes were mixtures; specifically each dye contained one or more of the other dyes as impurities. Inorganic impurities were detected by ashing the dyes in the presence of H2SO4 and chromatographing the sulfate salts on paper. They were removed by filtration through ion exchange resins. Organic impurities were detected by paper chromatography and removed by column chromatography on Woelm's neutral alumina.  相似文献   

3.
SYNOPSIS. Studies on the composition of commercial Giemsa stain and its effect upon staining quality are reported. These studies were supplemented by observations on the preparation of the components of Giemsa stain and their staining properties in aqueous solution, in Nocht's solution, and in laboratory prepared Giemsa stains containing one azure component. Five groups of commercial batches were differentiated on the basis of their staining reactions on thick and thin films of bovine blood containing Babesia bigemina and B. argentina. Spectrophotometric and chromatographic analysis showed that four groups differed in the proportions of the thiazine components present, while the fifth-group did not appear to be Giemsa stain. Comparison of their staining effects with those obtained with each component in laboratory prepared stains indicated that the major effects of commercial batches on both blood cells and parasites were due to the thiazine component or components in highest proportions, with satisfactory staining of protozoa associated with those batches containing high proportions of methylene blue and azure B and low proportions of the remaining thiazine components.
The function of each component of Giemsa stain is defined and the need for the proper balancing of thiazine eosinates with free azure is shown. Close correlation was obtained between analysis by spectrophotometry and chromatography and direct staining tests when samples initially with low MX values were re-examined spectrophotometrically after removal of their methylene violet content. The existence of a leuco form of eosin is reported and its possible significance to the Romanowsky effect is discussed.  相似文献   

4.
豆腐柴为一种民间用作制作传统观音豆腐的小型灌木。通过对所采集的鲜豆腐柴叶经pH值3.5的稀酸性溶液保温,70℃杀菌15min,使叶中果胶酶等酶失活后,于60℃烘干至恒重;干叶用料液比为1:20的盐酸进行酸解,滤液用2.5倍体积的食用酒精进行沉淀、纯化果胶。结果显示每千克干叶可得到纯化果胶0.27kg,果胶得率为27%,酯化度为53%,符合国家对果胶规定的标准,表明该提取方法可行。  相似文献   

5.
An investigation has been made of the staining properties of eight dyes of the thionin group. The dyes studied are as follows: tetra-ethyl thionin, asymmetrical di-ethyl thionin, tetra-methyl thionin (methylene blue), tri-methyl thionin (azure B), asymmetrical di-methyl thionin (azure A), symmetrical di-methyl thionin, mono-methyl thionin (azure C), and unsubstituted thionin. The staining properties were tested on sections of paraffin embedded material following five different methods of fixation. No counterstain was employed. It was shown that there was a general correlation between the extent of ethylation or methylation of the dyes and their staining properties. As one passes from tetra-ethyl thionin down the series to thionin itself, there is a progressive decrease in the amount of green showing in the preparations, and an increase in the amount of red present, also an increase in the metachromatic effects, and in the intensity of nuclear staining. There seems, also, to be a similar relation between staining qualities on the one hand and the color and solubility of the dye base on the other.  相似文献   

6.
An investigation has been made of the staining properties of eight dyes of the thionin group. The dyes studied are as follows: tetra-ethyl thionin, asymmetrical di-ethyl thionin, tetra-methyl thionin (methylene blue), tri-methyl thionin (azure B), asymmetrical di-methyl thionin (azure A), symmetrical di-methyl thionin, mono-methyl thionin (azure C), and unsubstituted thionin. The staining properties were tested on sections of paraffin embedded material following five different methods of fixation. No counterstain was employed. It was shown that there was a general correlation between the extent of ethylation or methylation of the dyes and their staining properties. As one passes from tetra-ethyl thionin down the series to thionin itself, there is a progressive decrease in the amount of green showing in the preparations, and an increase in the amount of red present, also an increase in the metachromatic effects, and in the intensity of nuclear staining. There seems, also, to be a similar relation between staining qualities on the one hand and the color and solubility of the dye base on the other.  相似文献   

7.
Olive oil hydrolyzing fraction (F-3) of Mucor lipase was separated into two fractions, F-3A and F-3B, by means of CM-Sephadex column chromatography. Both fractions were homogeneous and F-3A was crystallized. The pH optimum for olive oil hydrolysis of F-3A was at 9.0 and that of F-3B was at 8.0.

Chain specificities of the both enzymes were different with each other. Sedimentation coefficient (S20, w) of F-3A was 2.8 S and that of F-3B was 3.1 S.

Molecular weights calculated from sedimentation equilibrium data were 25,400 for F-3A and 29,000 for F-3B.  相似文献   

8.
以Wistar大鼠肝为材料,确立了一个简便的纯化鼠肝DNA甲基化酶的程序,包括:细胞的超声破碎、去内源核酸、硫酸铵盐析、磷酸纤维素亲和层析、DEAE-SephadexA-50柱层析及SephadexG-150凝胶过滤。用不同浓度聚丙烯酰胺凝胶电泳和孔梯度凝胶电泳检测,纯化后的酶已达电泳均一,且酶的比活力提高112倍。以聚丙烯酰胺孔梯度凝胶电泳测得其天然酶的分子量为365kD,以SDS-聚丙烯酰胺凝胶电泳测得该酶有两种亚基,大亚基为95kD,小亚基为85kD,推测该酶由两个大亚基和两个小亚基组成。  相似文献   

9.
In 29 thiazine and 12 oxazine dyes, greater metachromatic activity was found in thiazines than in their oxazine analogues. In the oxazine group only brilliant cresyl blue and the naphthophenoxazines showed marked mctachromasia. Metachromasia was not shown by members of the thiazine series with the following N-substituents: —NPr2; —NEt2; —NEtMe; —N(piperazino) and —N(morpholino). C-methyl substitution in positions 1 and 9 of the thiazine appeared to increase absorption in the beta peak relative to the alpha, even though the dye were nonmetachromatic; a peculiarity seen also in the naphthophenoxazines. Details of preparation, isolation and identification of the dyes are given.  相似文献   

10.
Antiviral interferon activity in any one species can be exhibited by a variety of substances that differ in their physical and chemical properties, but the nature of these differences is not understood. Conditions that can lead to the formation of diverse types of interferons have been outlined. Reasons have been adduced why, for certain purposes, purification of interferons is desirable or even necessary, and examples have been presented to show how and to what extent this has been achieved. In spite of some very high purification factors, not a single interferon has been obtained as a pure substance. Therefore, all available knowledge of physical and chemical properties has been obtained by indirect means.  相似文献   

11.
The purity of 27 commercial pyronin and rhodamine samples was studied by thin-layer chromatography and visible spectroscopy. Seven different red dyes were detected and separated. The chemical identities of 6 of these were established by nuclear magnetic resonance spectroscopy. The identities of samples sold as rhodamine B and rhodamine 6G were as labelled 8 out of 9 times, the pyronin (G)Y samples were as labelled 5 out of 8 times and the 10 samples sold as acridine red, pyronin B, rhodamine 36 and rhodamine S were always incorrectly labelled. The dextrin and salt contents of the dyes were determined by solvent extraction of the dye with dry methanol or ethanol. Amounts of dextrin and salt varied from none to nearly 90%. Practical methods for identification, separation of coloured components and removal of dextrin and salt are given.  相似文献   

12.
目的:表达纯化hPRL-1重组蛋白,分析其理化性质及酶学特性。方法:热激法将重组pET15b质粒转化入E.coli BL21中,IPTG诱导表达出His-tagged hPRL-1蛋白。使用Ni-NTA亲和层析法结合Mono Q离子交换层析法纯化。用SDS-PAGE法和Western Blot法进行表达情况的定性定量分析,并使用HPLC法鉴定蛋白纯度,计算出蛋白分子量,圆盘等电聚焦电泳分析重组蛋白等电点。比较分析以pNPP、4-MUP和DiFMUP为底物时的酶促反应动力学。同时以pNPP为底物测定酶的最适pH值;以4-MUP为底物测定酶的最适温度,分析探讨缓冲液离子强度与蛋白酪氨酸酶通用抑制剂钒酸钠对酶活力的影响。结果:以亲和层析和离子交换层析结合,可以纯化得到纯度约为95%的蛋白。测得蛋白分子量为24.54kD,等电点为9.11。以pNPP、4-MUP和DiFMUP为底物时Km分别为3720μmol/L,130μmol/L和50μmol/L。酶的最适pH值为7.6,最适温度为34℃。结论:纯化所得蛋白为目的蛋白hPRL-1;两步纯化相结合可以得到纯度较高的蛋白;三种底物特异性依次为DiFMUP>4-MUP>pNPP。  相似文献   

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16.
A study was made of the composition and biochemical behaviour of the drug, Laetrile, distributed for clinical trial in the United States and Canada. It was established that the Canadian and the American product are different pharmaceutical formulations, displaying different physicochemical and biochemical properties. The investigation demonstrated, furthermore, that neither preparation can be considered as a palliative in cancer therapy on the basis of the biological rationale advanced by their manufacturers.  相似文献   

17.
A number of antigens in unfertilized eggs and embryos of the sea urchin Paracentrotus lividus were characterized with respect to both immunological and physicochemical properties. Experiments involved single diffusion in agar (Oudin technique) combined with mutual dilution, serial dilution, and heating of antigenic extracts, as well as immunoelectrophoresis with normal and heated extracts and agar electrophoresis followed by staining of the antigenic spots with protein specific dyes. The gradual transition in migration rates of bands of precipitates in Oudin tubes following mutual dilution of either extracts or antisera allowed the identification of 6 immunologically identical antigens in eggs and embryonic stages. Similarities with respect to diffusion coefficients, sensitivity to heat, electrophoretic mobility, and reaction to protein specific dyes indicated that the antigens in extracts of eggs and various developmental stages also had certain physicochemical properties in common. Such knowledge is of importance for an understanding of antigenic changes occurring during ontogenesis.  相似文献   

18.
Summary An extracellular protease ofSerratia marcescens produced during growth on skim milk medium was isolated by ethanol precipitation. The protease was purified by salt fractionation, DEAE-cellulose ion exchange chromatography and gel filtration chromatography on Agarose P-100. It has a broad optimum from pH 6.0 to 9.0 and a temperature optimum of 45°C for proteolytic activity on casein. It was classified as a metallo-protease by virtue of its inactivation by metal-ion chelators and reactivation by ferrous ions. Proteolytic activity was not affected by diiso-propylfluorophosphate, p-chloromercuribenzoate and dithiothreitol.  相似文献   

19.
Two forces are in general, hypothesized to have influenced the origin of the organization of the genetic code: the physicochemical properties of amino acids and their biosynthetic relationships. In view of this, we have considered a model incorporating these two forces. In particular, we have studied the optimization level of the physicochemical properties of amino acids in the set of amino acid permutation codes that respects the biosynthetic relationships between amino acids. Where the properties of amino acids are represented by polarity and molecular volume we obtain indetermination percentages in the organization of the genetic code of approximately 40%. This indicates that the contingent factor played a significant role in structuring the genetic code. Furthermore, this result is in agreement with the genetic code coevolution hypothesis, which attributes a merely ancillary role to the properties of amino acids while it suggests that it was their biosynthetic relationships that organized the code. Furthermore, this result does not favor the stereochemical models proposed to explain the origin of the genetic code. On the other hand, where the properties of amino acids are represented by polarity alone, we obtain an indetermination percentage of at least 21.5%. This might suggest that the polarity distances played an important role and would therefore provide evidence in favor of the physicochemical hypothesis of genetic code origin. Although, overall, the analysis might have given stronger support to the latter hypothesis, this did not actually occur. The results are therefore discussed in the context of the different theories proposed to explain the origin of the genetic code. Received: 10 September 1996 / Accepted: 3 March 1997  相似文献   

20.
Two lectins, Leaf Lectin I and Leaf Lectin II (LLI and LLII) were purified from the leaves of Sophora japonica. Like the Sophora seed lectin, LLI and LLII are tetrameric glycoproteins containing a single subunit with respect to size. The subunits of LLI (32 kilodaltons) and LLII (34 kilodaltons) are slightly larger than those of the seed lectin (29.5 kilodaltons). The three Sophora lectins display indistinguishable specificities, amino acid compositions, specific hemagglutinin activities, and extinction coefficients. Although very closely related to the seed lectin, the leaf and seed lectins are not immunologically identical and they differ in subunit molecular weights, carbohydrate content, and in the pH sensitivity of their hemagglutinin activities. N-terminal amino acid sequence analysis shows that although they are homologous proteins, the three Sophora lectins are products of distinct genes.  相似文献   

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