Saburo Kanno

Formation of cyanide ion or cyanogen chloride through the cleavage of aromatic rings by nitrous acid or chlorine. XI

Cyanogen chloride was formed by the reactions of purine bases (adenine and guanine) with hypochlorous acid in the presence of ammonium ion. The origin of the carbon and nitrogen atoms of cyanogen chloride formed from adenine was investigated by use of synthetic adenines variously labeled with the isotope of nitrogen ( 15 N) or carbon ( 13 C)

Studies on Analysis of Food Additives (VIII)

The existing method for determining nitrite ion in fish sausage, for example, themethod being included in “Standard Methods of Sanitary Inspection Guide” issued by the Ministry of Health and Welfare was studied.The authors clarified the following points through analytical experiments.1) The nitrite ion in a test solution prepared from fish sausage disappeared completely when the solution was distilled. Therefore, the test solution should be developed without distillation, though it is colored or turbid, and in this case, the test solution should be used as a control.2) The phosphate buffer solution (pH 7) as an extracting solvent for nitrite ion (NO2-) was more effective than water. Because the loss of the nitrite ion was less with the use of the buffer solution than water.3) Thirty minutes were quite enough to extract nitrite ion from fish sausage.

Hygienic Chemistry of Cyanide in Waste Water

It has been discussed and proposed by the Central Pharmaceutical Affairs Council of Japan that the maximum allowable concentration of cyanide ion (CN-) in plating waste water should be under 2 ppm. The standard value of 2 ppm is not applied to such complex cyanides as ferrocyanide and ferricyanide, but to the free cyanide which is liberated by aeration through the test solution at pH 5.0 and 50∼55°C, because the toxicity of the complex cyanide is less than onethousandth of that of the free cyanide. The determination procedure of free cyanide ion listed in Japanese Industrial Standard (JISK0102-1964) was modified to improve in several points, for example, pH control of the test solution and the adoption of ball filter in aeration apparatus and 1N NaOH solution as absorbing solution for HCN. The methods for removal of HCN, such as alkali-chlorine method and Fe-complex method, were reviewed shortly.

Determination of alkyl benzene sulfonate in water

従来のメチレンブルーを用いる水中のアルキルベンゼンスルホン酸ナトリウム(ABS)の定量法において,他のアニオン活性剤による妨害を除く目的で,まず塩酸煮沸を行ない妨害物を除去したのち,Longwell-Maniece(L.M.法)法によった.すなわち,ABSとして0.02～0.14mgを含むよう検水を適当量とり,希釈または濃縮して約50mlとし,これに塩酸25mlを加え,還流冷却器をつけ,1時間静かに煮沸する(たとえば,ラウリル硫酸ナトリウム1mgが加水分解される).放冷後,水酸化ナトリウム溶液で中和し,水で約100mlとし,これについてL.M.法を適用した.定量範囲は波長654mμ,セル幅10mmにて0.02～0.14mgABS/50mlクロロホルムである.

Studies on Analysis of Nitrofuran Derivatives (V)

α-Furyl-β- (5-nitro-2-furyl) -acrylic acid amide (AF-2) and nitrofurazone (NFS) in meat products were analysed separately. Nitrofurylacrylamide (NFA) combines with protein. AF-2, after washing the sample with petroleum ether, was extracted with toluene and determined at 395mμ. NFS, after extracting AF-2 with toluene from the sample, was reacted with henylhydrazine and determined at 440mμ. Each of the photometric methods were not interferred by other components. The recoveries of each components were above 70-85%.

On Nitrofurasone and Nitrofurylacrylic acid amide in Food

During our experimentation on the analysis of nitrofurasone (NFS) and nitrofurylacrylic acid amide (NFA) in food (meat, fish meat, and bean juice), it was clarified that NFS was found at the recovery rate of about 80% but NFA was difficult to be diticted.That is presumably because NFA combines with protein. Judging from the fact, the effectiveness of NFA as an antimicrobial agent will be doubtful.

Determination of Minute Amounts of Arsenic by means of Detector Tubes

従来行われているヒ素の微量定量法としてのGutzeit法は定性法としては十分であるが,定量法としては,なお若干の難点がある。すなわち,ロ紙の幅,表裏,ガラス管への挿入状態等によって着色層の長さが異なり,かつその先端が明瞭でないこと等のためにその測定値の精度が低いことである。著者らはGutzeit法を改良する目的で着色装置としてロ紙の代りに検知管を用いることにより,これらの欠点を克服しようとした。まずヒ化水素により鋭敏に着色する試薬の探索を行った結果,塩化金を採用し,この一定量をシリカゲル粒に吸着,乾燥し,鋭敏に白色から濃紫青色に変わる検知剤をえ,これを細いガラス管に一定量充填して検知管を作製した。次にGutzeit法の試験装置のうち,臭化第二水銀紙細管の代りに検知管を用い,ヒ化水素を40分間発生させ,生じる検知管の着色層の長さから微量のヒ素の含有量を求めた。その結果はAs2O3として0.5～40γのヒ素を精度よく本法により定量できた。