Topic
Color reaction
About: Color reaction is a research topic. Over the lifetime, 1194 publications have been published within this topic receiving 19579 citations.
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09 Mar 1981
TL;DR: The polyene antibiotic substance T-23-W having the following characteristics: elemental analysis, C 63.03%, H 5.87%, O 31.10%; molecular formula, C 27 H 30 O 10 ; melting point, 149W150°C; solubility, soluble in ethanol and methanol, hardly soluble in acetone and ethyl acetate, insoluble in water, chloroform and hexane; color reaction, negative to ninhydrin reaction, ferric chloride reaction, and aniline phthalate reaction; appearance, acidic yellowish powder
Abstract: NEW MATERIAL:The polyene antibiotic substance T-23-W having the following characteristics: elemental analysis, C 63.03%, H 5.87%, O 31.10%; molecular formula, C 27 H 30 O 10 ; melting point, 149W150°C; solubility, soluble in ethanol and methanol, hardly soluble in acetone and ethyl acetate, insoluble in water, chloroform and hexane; color reaction, negative to ninhydrin reaction, ferric chloride reaction, and aniline phthalate reaction; appearance, acidic yellowish powder. USE: Antimicrobial agent having excellent activity against molds, yeasts, nematodes, etc. PROCESS: Gluconobacter oxidans T-23-W (AJ11665, FERM-P No.5896) which is a bacterial strain belonging to Gluconobacter genus, is cultured aerobically in a medium containing a cultivation liquid medium of mold such as Neurospora crassa, etc., and preferably the pH of the medium is made acidic. The medium is extracted with a water-immiscible organic solvent, dried, and purified to obtain the objective antibiotic substance T-23-W. COPYRIGHT: (C)1982,JPO&Japio
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TL;DR: In this article, the ammonium concentration of the fermentation broth sample containing sodium sulfite, including some microorganism cells, could be determined satisfactorily by the Berthelot color reaction method modified.
Abstract: Sodium sulfite seriously interfered ammonium measurement in fermentation broth by Berthelot color reaction methodPretreatment of samples by adding proper amount of sodium hypochloride was found effective to remove the interferenceThe adding amount of sodium hypochloride,pretreatment time and sample pH were investigatedIt was confirmed by ion chromatography analysis that the ammonium concentration of the fermentation broth sample containing sodium sulfite,including some microorganism cells,could be determined satisfactorily by the Berthelot color reaction method modified
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TL;DR: A hitherto undescribed reaction produced by the D vitamins, producing a clear and limpid blue colour which is thought to be used for quantitative estimations is found.
Abstract: While making a comparative study of the colour reaction of steroids and triterpenes, we have found a hitherto undescribed reaction produced by the D vitamins, producing a clear and limpid blue colour which we think might be used for quantitative estimations. We carry out Pettenkofer's reaction for the biliary acids as follows: to 1–2 mgm. calciferol is added 1-2 mgm. saccharose, and the whole is dissolved completely in 1–2 c.c. of absolute ethanol. Then we add two drops of concentrated sulphuric acid, giving a red colour; then six drops of sulphuric acid are added, giving a stark blue colour. The test-tube is shaken to mix the two layers. The colour diffuses throughout the liquid, and the definitive colour is a pale limpid blue.
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TL;DR: In this article, a new chromogenic reagent for a rapid, simple, selective, direct and non-extractive spectrophotometric method is developed for the determination of mercury (II) in aqueous dimethyl formamide (DMF).
Abstract: 2-acetylfuran isonicotinoyl hydrazone (AFINH) has been synthesized and proposed as a new chromogenic reagent for a rapid, simple, selective, direct and non-extractive spectrophotometric method is developed for the determination of mercury (II) in aqueous dimethyl formamide (DMF). The reagent gives deep yellowcoloured, 1:1 (M: L) complexwithmercury (II) in sodium acetate-acetic acid buffer medium of pH 5.5 at emax 365 nm. The colour reaction is instantaneous and the absorbance remains constant for about 12 hrs. The molar absorptivity ofmercury complex is 2.3 x 103 Lmol- 1 cm-1 and sandellÂÂÂs sensitivity are found to be 0.0888 µgcm-2. The method was successfully applied to a number of environmental, biological and soil samples. The results were comparable with those obtained by dithizone method. The proposed system produced satisfactory results for the determination ofHg (II). The results are quite encouraging and can bring awareness among the public. iÂÂÂÂ 2013 Trade Science Inc. - INDIA.
1 citations