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901.
902.
Colorimetric determination of phytate in unpurified extracts of seeds and the products of their processing 总被引:7,自引:0,他引:7
The addition of orthophosphate (up to 20 micrograms/ml of phosphorus) and chlorogenic acid (up to 50 micrograms/ml) does not impair the colorimetric assay of phytate based on the decoloration of Fe3+-sulfosalicylate complex (M. Latta, and M. Eskin (1980) J. Agric. Food Chem. 28, 1313-1315). Phytate was determined in 14 samples of seed meal and protein isolates containing inorganic phosphate and chlorogenic acid. There was no difference between the results of the analysis using crude extracts and those using purified extracts. It is therefore possible to avoid the preliminary purification of extracts as in the original method, thereby simplifying and accelerating the phytate assay to a considerable extent. 相似文献
903.
A number of acetoxycarboxylic acid esters were hydrolysed enantioselectively by Saccharomyces cerevisiae Hansen leading to chiral hydroxycarboxylic acid esters of high optical purity. The scope and limitations of this method with respect to the substitutional pattern of substrates were investigated. Subcellular localization of the hydrolytic activity on the plasma membrane led to the assumption that unspecific carboxyl esterases are responsible for hydrolysis of this type of substrate. Comparative experiments using viable cells and lyophilized cells as source of enzyme revealed the latter to be superior with respect to enantioselection and ease of handling. 相似文献
904.
The present study reports the isolation and characterization of a cadmium-containing glycoprotein from the water-soluble fraction of an aquatic insect. The isolated glycoprotein contained 0·67% cadmium, 62·1% carbohydrate, and 37·2% protein. The glycoprotein appears to be involved in the detoxification of cadmium, because species insensitive to cadmium contain five times the amount of the glycoprotein as do species sensitive to cadmium. 相似文献
905.
906.
SYNOPSIS. A new species of Microsporida, Burenella dimorpha sp. n., representing a new family, Burenellidae fam. n. and genus, is described on the basis of light- and electron-microscope observations. The family is characterized by 2 sequences of sporogony, each sequence having morphologically different sporonts and spores. The parasite infects the tropical fire ant, Solenopsis geminata (Fabricius), producing distinct pathologic manifestations (clearing of the cuticle and eye malformation) and death in the pupal stage of development. Transmission of the infection per os to healthy S. geminata, to the Southern fire ant, Solenopsis xyloni McCook, and to the red and black imported fire ants, Solenopsis invicta Buren and Solenopsis richteri Forel, is reported. 相似文献
907.
Iu B Lishmanov T V Fedotova M I Titov 《Biulleten' eksperimental'no? biologii i meditsiny》1989,107(6):704-706
The protective action of enzymatically stable analogue of Leu-enkephalin (D-ala-2-leu5-arg6), injected intraperitoneally, in the course of stress- and epinephrine induced myocardial damage was demonstrated in animal (129 white rats) experiments. Two effect of enkephalin were sufficient for the cardiac protection: enkephalin-stimulated prostacyclin biosynthesis and simultaneous inhibition of thromboxane production. 相似文献
908.
909.
910.