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Direct ELISA was performed using normal human sera and human colostrum, to analyse the presence of antibodies which react with pharmacologically active pectic polysaccharides isolated from plants used in traditional Japanese herbal (Kampo) medicine. All sera and colostrum were shown to contain IgM, IgG, IgA and secretory IgA class antibodies which react with the active pectic polysaccharides to different degrees. The reacting IgG antibody in normal human serum recognized the ramified regions (rhamnogalacturonan core with carbohydrate side-chains) of the pharmacologically active pectic polysaccharides as the active sites for complement-activating activity. Correlation analysis indicated that a significant and positive correlation was observed between reactivity with the reacting antibody of IgG class and the degree of complement-activating activity of the active polysaccharides.The reacting IgG class antibody, which was purified from normal human serum by affinity chromatography on bupleuran 2IIc (a pharmacologically active pectic polysaccharide from the roots of Bupleurum falcatum)-immobilized Sepharose, showed cross-reactivity not only with some other pharmacologically active pectic polysaccharides from other medicinal herbs but also with autoantigens such as single-strand DNA, myosin and tublin from mammals.  相似文献   
3.
The 2,3-Dihydro-lH-pyrrolo[l,2-a]indole ring system was synthesised by the condensation reaction of toluquinone and 2-cyanomethylenepyrrolidine.  相似文献   
4.
Six subunits of arachin were isolated in urea solution. They were then reassociated by removing urea by co-dialysis against 20 mM sodium phosphate buffer (pH 7.9), containing 30% sucrose, 0.1 M> sodium chloride and 7 mM β-mercaptoethanol, without agitation at 25°C. The reconstitution yield was greater than 90%. The reconstituted molecule was indistinguishable from intact arachin in disc electrophoretic mobility, subunit composition, sedimentation behavior depending upon ionic strength, circular dichroism, ultraviolet absorption and fluorescence emission spectra, and stabilities against heating, proteases and guanidine hydrochloride. The reconstituted arachin was, therefore, suggested to be in native state.

On the other hand, we found that co-dialysis of four or five subunits of arachin formed hexamer which contained the corresponding four or five subunits. These hexamers were more labile than intact arachin against heating. These facts suggest that the assembly of all six subunits to a hexamer will most advantage the quaternary structure of arachin.  相似文献   
5.
The formation of D-pantothenic acid-α-glucoside (PaA-α-G) was found from D-pantothenic acid (PaA) and maltose in incubation mixtures of microorganisms, especially Saccharomyces yeasts and Sporobolomyces coralliformis IFO 1032. The reaction conditions were investigated for formation of PaA-α-G by resting cells of Spor. coralliformis. The formation of the compound increased with PaA concentration (3~20 mg/ml). The yield was maximum at 5~10 mg/ml of PaA. Cetyl trimethyl ammonium bromide (0.1 %) promoted the formation of PaA-α-G. Sucrose was the optimal α-glucosyl donor. When 30 mg/ml of sucrose was fed to the reaction mixture (initial sucrose, 100 mg/ml; and PaA, 10 mg/ml) at 12-hr intervals, 5.74 mg/ml (3.30 mg/ml as PaA) of PaA-α-G was formed in 48-hr incubation at 28°C with shaking. PaA-α-G was also formed by yeast α-glucosidase, mold maltase and the cell-free extract of Spor. coralliformis. The compound showed approximately 9~10% and 0.1~0.3% (molar ratio) of activity of PaA for Saccharomyces carlsbergensis ATCC 9080 and Lactobacillus plantarum ATCC 8014, respectively. The compound had the same microbiological activity as authentic 4′-O-(α-D-glucopyranosyl)-D-pantothenic acid.  相似文献   
6.
Some benzophenones substituted with methyl, methoxy, hydroxy or halogen groups inhibited growth and induced chlorosis in various plants. The structure activity relationships about the chlorosis-inducing activity and the growth inhibitory activity of the 3-methyl-benzophenones were well expressed by use of hydrophobic contant π, and Hammett’s σ. The highest selectivity for phytotoxic activities against barnyardgrass and the rice plant was with 3,3′-dimethyl-4-methoxybenzophenone (Methoxyphenone).  相似文献   
7.
Various conditions for obtaining hybrids of the auxotrophic mutants SH1509 and SH1512 of Saccharomyces cerevisiae by electrofusion were investigated. An AC field of 400 Vp/cm and a DC field of 2 square pulses (7 kV/cm; 60/βsec each) at an interval of 0.5 sec were effective. Treatment with 0.2 (SH1509) or l.0 mg/ml (SH1512) Zymolyase for 1 or 1.5 hr was essential. As to the molarity of the osmotic stabilizer (sorbitol), the hybrid yield peaked at 0.6 m. The presence of CaCl2 (up to 0.4 mm) or 0.1 mm CaCl2 with 0.1 mm MgCl2 enhanced the yield. The temperature of the spheroplast suspension during pulsations also affected the yield, the most suitable temperature being 28°C.  相似文献   
8.
Dimethylglycine oxidase was purified to homogeneity from the cell extract of Cylindrocarpon didymum M–1, aerobically grown in medium containing betaine as the carbon source. The molecular weight of the enzyme was estimated to be 170,000 by the gel filtration method and 180,000 by the sedimentation velocity method. The enzyme exhibited an absorption spectrum characteristic of a flavoprotein with absorption maxima at 277, 345 and 450 nm. The enzyme consisted of two identical subunits with a molecular weight of 82,000, and contained two mol of FAD per mol of enzyme. The flavin was shown to be covalently bound to the protein. The enzyme was inactivated by Ag+, Hg2+, Zn2+ and iodoacetate. The enzyme oxidized dimethylglycine but was inert toward choline, betaine, sarcosine and alkylamines. Km and Vmax values for dimethylglycine were 9.1 mm and 1.22 μmol/min/mg, respectively. The enzyme catalyzed the following reaction: Dimethylglycine+O2+H2O → sarcosine+formaldehyde+H2O2.  相似文献   
9.
Cryostorage is one suitable method to preserve various desired types of cells. However, all cells do not survive after storage in liquid nitrogen. This suggests the possibility that the properties of the cells which survive after the storage differ from those of the unfrozen original cells.

Therefore, we did the same freeze-thaw procedure of cultured green Lavandula vera cells over again and compared the metabolic and the differentiation potentials of the cells which survived after the repeated freeze-thaw procedures with those of the unfrozen original cells. The results we found were that the frequency of colony formation of the cells which survived after the procedures was high, but that the biosynthetic capability for biotin and the differentiation potentials such as chloroplast formation and plantlet formation of the cells were equal to those of the unfrozen original cells. Cryostorage of cells in liquid nitrogen is discussed in terms of the preservation of various desired types of cells.  相似文献   
10.
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