タール系食用色素の多成分混合物をクロマトグラフ的分離を行わずに, 二波長測光法によって直接分別定量することを試みた. この際, 通常の光分析におけるマトリックス法を加味した.
2種 (B-1・R-2・Y-4およびB-1・R-2・Y-4) の三成分混合物系と2, 種 (B-1・R-2・Y-4およびB-1・AV-6・R-3・Y-4) の四成分混合物系について, それぞれ0.02N酢酸アンモニウム溶液として4種類の混合溶液系を調製し, 適当な測定波長 (λ₂) と対照波長 (λ₁) 間の差吸光度に対して主副検量線を作成後, 分別定量した結果, 2種の三成分混合物系では添加量 (1～6μg/ml) と定量値間の回帰分析を行ったところ, 標準誤差は0.022～0.098μg/ml, 相対標準誤差は0.75～3.90%であった. 2種の四成分混合物系でも各スペクトルの重畳が少ないような条件下では前者と同程度の定量確度が得られた. しかし, 一般的には三成分までが二波長測光的考慮での定量分析の限界と考えられる. さらに化学構造および可視吸収スペクトルの酷似した厳しい条件下での混合物としてキサンテン系食用色素4種についての多成分混合物を対象として同様の検討を行い, 定量分析法としての可能性の限界を検討した.
4種の三成分混合系のうち, R-6・R-3・R-105系では各混在色素量1～6μg/mlの範囲において, 添加量と定量値の回帰分析をした結果, 標準誤差0.035～0.058μg/mlであった. 他の三成分系も標準誤差0.055～0.402μg/ml (Table 5参照) を示した. 全色素を混合した四成分系では. 互いのスペクトルの重畳が著しく, 赤色106号を除いて定量は困難であった. したがって, 本法によるキサンテン系色素の定量法の限界は三成分までと考える. しかし, 今後, マトリックス法による消去が機械的に行われれば, このような類似スペクトルを有する食用色素の多成分混合製剤に対しても, 食品から溶出した色素混合物に対しても, さらに簡便で正確な多成分二波長分別定量法の確立が可能となるだろう.

抄録全体を表示

On the standpoint of dual-wavelength spectrophotometry, each component in 156 groups of two-components mixture consisting 11 kinds of food colors and of 2 kinds of similar colors was directly analyzed with ordinary spectrophotometer without chromatography. Measurement for calibration equations was made in the 0.02N ammonium acetate solution ranging in concentration of these dyes from 0 to 10μg/ml.
The reference wavelength (λ₁) and measurement wavelength (λ₂) chosen were shown in Table 2, and difference absorptivity between λ₁ and λ₂ were also shown in Table 3. Mean standard deviation between amounts of added dye and those of found dye in monoazomonoazo mixture was 0.03μg/ml (analyte+interfering dye=5μg/ml). In the case of acid red interfered by another dye, 0.099μg/ml was obtained, but the total mean standard deviation was 0.067μg/ml for all mixture groups. Dye contents in commercial dye were quantitatively analyzed by this procedure.

抄録全体を表示

Each dye in three-components mixture for food was quantitatively determined with the absorption multiplier attached to a dual-wavelength spectrophotometer. When there are no isoabsorbance wavelengths on the absorption spectrum of a material in two-components mixture because of their linearity, it may be desirable to take two wavelengths (λ_m, λ_r) between which the analyte in the mixture show an appreciable difference absorbance. If the ratio (masking factor=m/r) of the absorbance at wavelengths λ_m and λ_r is known, the absorbance error caused by changes in concentrations of that is eliminated electrically by the absorption multiplier. Thus, the apparent difference absorbance of the analyte can be measured between measuring wavelength λ_m and reference wavelength λ_r in the presence of the other.
Absorption spectra of two colors in the two-components mixture, may have two points (λ_m and λ_r) of intersection on absorbance curves by alternation of their concentrations. Then, the analyte must possess the appreciable absorption between the above points. The apparent absorbance of analyte may be measured after the instrumental masking of other interfering components by multiplication of the absorptivity at λ_r by the masking factor (m/r). All measurements were made with a Model UV-300 Shimadzu double beam/difference/dual-wavelength recording spectrophotometer on the solutions (0.02N ammonium acetate) ranging in concentration of these dyes from 0 to 20μg/ml.
For six kinds of three-components system, calibration equations were obtained between the apparent difference absorbances and the content of an analyte (0-11.5g/ml) in the presence of other interfering components (total 10μg/ml). For six kinds of three-components mixture, each dye was determined by using an artificial mixed solution (each 33.33%) with the recovery of 92-107% (Table 2) and the contents of commercial samples were analyzed by this procedure with. recovery ranging from 86 to 105% for labelled amoutes for seven species (Table 3).
This method may be easily useful for a quantitative analysis of multicomponent mixtures for food.

抄録全体を表示

Absorption coefficients at characteristic wavelengths on absorption and derivative spectra (1st and 2nd order) were obtained for 11 kinds of food colors and 2 kinds of similar dyes on the 0.02N ammonium acetate solutions ranging in concentration of these dyes from 0 to 20μg/ml. The time derivative method for 1st and 2nd derivative spectrophotometry was introduced and facilitate more the detection of each component in dye mixture for food from the shape of standard derivative spectrum (especially, the spectrum of 2nd-order derivative) than the ordinary derivative method with duochrometer, and also facilitate more accurately the determination of the component even in the case of turbid solution.
Several kinds of synthetic two-components mixture (each: 0-10μg/ml) were simply and rapidly identified and determined with the recoveries of 98-133% by 1st deravative spectrophotometry and of 99-106% by 2nd derivative method. For eight kinds of threecomponents mixture containing equal amounts of dyes (each: 33.3%), each component dye was also identified and determined with the recoveries of 86-112% by 2nd derivative spectra. This method was satisfactorily applied to the rapid analysis of food colors in seven kinds of commercial three-components mixture.

抄録全体を表示

小麦グルテン, リジン添加小麦グルテン, 大豆粉末および脱脂大豆粉末を水とアルカリでそれぞれ抽出したタンパク質について, リジノアラニン (LAL) の生成に対する温度とアルカリの影響を調べるとともに, LALの分解についても検討した.
1) いずれの試料でも, 水に浸して室温, 100または150°に60分間加熱した場合およびアルカリに浸して室温に60分間放置した場合, LALの生成はみられなかった. アルカリに浸して100または150°に60分間加熱した場合, LALは生成し, 総リジン量はやや減少した. これに対して180°に30分間加熱した場合には, アルカリの存在に関係なくLALは検出されなかった.
2) 小麦グルテンにL-リジンを添加した場合, アルカリに浸して加熱すると, 小麦グルテン単独の場合よりLALの生成が増加した.
3) 室温において, 脱脂大豆粉末から水で抽出したタンパク質では, LALは検出されなかったが, 0.2N水酸化ナトリウム溶液で抽出したタンパク質では, LALの生成がみられた. 一方, 水抽出タンパク質をアルカリの存在下で加熱すると, LALが生成したが, その生成量は1) の場合に比較してかなり少なかった. また, アルカリ抽出タンパク質を加熱すると, 加熱前よりLALの量が増加したが, その増加量は大きいものではなかった.
4) LAL画分をアルカリの存在下で, 100, 120および130°に加熱すると, LALは順次減少して, ゴジンが増加した. 130°ではLALはほとんど検出されず, リジンが理論値の約69%生成した.

抄録全体を表示

1. カキ90例のうち24例 (26.6%) から耐性を示す大腸菌群を分離した. 耐性菌の種類はE. coli, C. freundiiおよびK. aerogenesであった.
2. 分離菌の大多数は多剤耐性で, 単剤耐性は12%にすぎなかった. 菌種別にみると, 多剤耐性菌はE. coliでは13/15株 (86.7%), C. freundiiでは53/57株 (93%) であった. 主な耐性型は, 前者ではSM・SAおよびTC・CP・SM・SA・APCであり, 後者ではS・M・APCであった.
3. 分離菌75株中10株がRプラスミドを保有し, その耐性型はすべて多剤耐性であった. 菌種別にみると, E. coliは7/15株 (46.7%) がRプラスミドを保有し, その耐性型は [TC・CP・SM・SA・APC] および [SM・SA] であった. C. freundiiでは3/57株 (5.3%) がRプラスミドを保有し, 耐性型はすべて [TC・SM] であった.
4. RプラスミドのE. coli K-12 ML1410への伝達頻度は供与菌当たり10-2～10-3程度であった.
5. 検出されたRプラスミドのfi型はfi^-およびfi⁺の2型であった.

抄録全体を表示

食品中の残存亜硫酸を, ヘッドスペース法とFPD付きGCを組み合わせて定量することを検討した結果, 以下のとおりであった.
1) 亜硫酸標準溶液を用いて, 定量法の基礎的条件を検討したところ, 再現性が認められた.
2) 本法の定量限界は亜硫酸として2μgであり, 測定範囲は2～50μg/gである.
3) 抽出操作をpH 7.0～7.5の範囲で行うことにより, 結合型亜硫酸も測定可能となった. また, ある種の食品に含まれると考えられる有機イオウ化合物による定量妨害もなかった.
4) 各種食品に亜硫酸を添加した際の回収率は95.3～101%であった.

抄録全体を表示

NDMをラットに経口投与した場合, 大部分は速やかに腸から吸収され, 肝臓で分解された. 投与量が多量 (50mg/kg) になると, 一部は尿中に直接排せつされた.
あらかじめNDMを50mg/kg投与したラットの肝臓と, 非投与のラットの肝臓とのin vitroにおけるNDM分解能を比較すると, 投与ラットにおいてはNDM分解能は正常ラット肝の51%に低下し, さらに1日1回2日連続投与では41%に減少した.

抄録全体を表示

The muscle of rudder fish (one of the deep-sea fishes, Centrolophus niger: Stromateidae) contained a large amount of lipid which showed an extremely higher value for unsaponifiable matter contents and lower saponification value than of other fishes. Moreover the lipid showed very low triglyceride contents. The trimethylsilyl derivatives of unsaponifiable matters were analyzed by the methods of gas-liquid chromatography and mass spectrometry. These results assured that the unsaponifiable matters had the 1, 2-diol structure, and were presumed to be glyceryl ethers. We also investigated about the muscle lipids of some deep-sea fishes (silver king fish: Rexea solandri, silver fish: Sriollela punctata, Black cod: Anopiopoma fimbria). The triglyceride was the major constituent of their muscle lipids. Among them, silver king fish had the lowest saponification value and the highest contents for unsaponifiable matters which showed the same properties as that of rudder fish.

抄録全体を表示

In the previous paper, it was assumed that the unsaponifiable matters of rudder fish and silver king fish had the 1, 2-diol structure. This paper showed the existence of the C-O-C bond (ether bond) by means of infrared spectroscopy and hydrogen iodide degradation. Therefore the unsaponifiable matters were presumed to be glyceryl ethers and the molecular weights were measured by the mass spectroscopy of their isopropyridene derivatives. The glyceryl ethers bind two carboxylic acids and exist as diacyl glyceryl ethers in the lipids. It may be that the low eyolution, the inhabitation of deep-sea and the function of the body were considered as the cause of the existence of diacyl glyceryl ethers. It is suspected that diacyl glyceryl ethers in rudder fish may cause diarrhea for somebody.

抄録全体を表示

熱媒体として使用されたKC-400のPCDF濃度は市販KC-400の8.4倍 (277ppm) および15.5倍 (510ppm) になっており, 主成分は4～6塩化PCDFで, 長期間, 高温で使用するほど, 高塩化PCDFの割合が多くなっていた. PCDF組成は油症原因油中のPCDFに比較的類似していたが, PCDF/PCB濃度比は1～2オーダー低いものであった.
一方, 閉管ガラスアンプル中でPCBを加熱すると, 180～300°ではPCDFの生成は少なく, 360°にすると急激に生成し, PCDF濃度は2～2.8倍に増加した. ステンレススチールはPCDF生成に触媒的に作用することが判明し, さらに, 水はPCBからPCDF生成を増加させ, 反応に関与することが明らかになった. しかし, 生成したPCDFは3～5塩化物が多く, 油症原因油のPCDF組成と異なっていた.

抄録全体を表示

The nitrosation of methyl N-methylanthranilate (MMA), which is permitted to be used to foods as flavor in Japan, with equimolar nitrite was measured at 37°C at the concentrations of 10^-1-10mM of both reactants. MMA was nitrosated very easily, and when 0.1mM of MMA was reacted with equimolar sodium nitrite at pH 2.0 fbr 5min and at pH 3.0 for 20min, the yields of methyl N-methyl-N-nitrosoanthranilate (NO-MMA) were 89.5% and 82.6%, respectively. The rate of nitrosation was found to be dependent on the acidity of reaction mixture and the highest yields of NO-MMA was obtained below pH 2.0 at the MMA concentration of 0.2mM for 5min. A mutation test of NO-MMA was carried out, but NO-MMA was non-mutagenic to Salmonella typhimurium tester strain TA 100 and TA 98 in the presence and absence of the metabolic activation system (S9 mix).

抄録全体を表示

Levels of nitrosatable compounds in saliva and urine were determined. The mean value, which was calculated as equivalent to dimethylamine (DMA) in 25 human saliva samples cellected from 11 subjects was 0.3±0.2ppm. When a subject ingested the foods containing low levels of volatile nitrosatable compounds the concentration of nitrosatable compounds in saliva was less than 0.2ppm over the day, but increased to 1.0ppm 1hr after the ingestion of 100mg of DMA·HCl with 100ml of water. DMA remaining in the oral cavity after the ingestion of DMA·HCl disappeared within 20min. No changc in the concentration of nitrosatable compounds was observed when the saliva collected 1hr after the ingestien of DMA·HCl was incubated a t 37°C for 2hr. DMA was identified as the main nitrosatable compound in saliva, which was cellected after the ingestion of DMA·HCl, by thin-layer chromategraphy and gas liquid chromatography. The pattern of the time course of urinary excretion of nitrosatable compounds after the ingestion of DMA·HCl was almost similar to that of the salivaly secretion. About 95% of DMA ingested was presumcd to be excreted as nitresatable compounds into 24-hr urine.
The mean value of the amounts of nitrosatable compounds excreted in the 24hr urine collected from 9 subjects was 21.1±9.3mg and that of volatile nitrosatable compounds contained in the foods and beverages ingested for the experimental period was 10.4±6.9mg.

抄録全体を表示

During the period from July 1975 through October 1976, a total of 3, 551 samples of commercial food, consisting of 730 soybean curd (Tofu), 698 sandwiches and salad, 698 European type of cake, 485 boiled Japanese noodle, 259 Japanese cake, and 681 miscellaneous foods in Tokyo, was subjected for the presence of Bacillus cereus. Of them, 398 (54.5%) of soybean curd, 79 (11.3%) of sandwiches and salad, 74 (10.6%) of European type of cake, 44 (9.1%) of boiled Japanese noodle, 15 (5.8%) of Japanese cake, and 57 (8.4%) of miscellaneous foods were found to be contaminated with B. cereus. The most highly contaminated food was soybean curd with a maximum amounts of 10⁶/g of the organisms, while other foods were found to be contaminated with 10²-10⁴/g of the organisms.
When 667 B. cereus isolates were typed by their flagella antigens by the method described by Taylor and Gilbert, 150 (22.5%) isolates were typed into their 1-18 serotypes and 276 (41.4%) were typed into the additional our own T1-T12 serotypes, while the rest of 241 (36.1%) were untypable. Of the typed isolates, 88 were typed as T11, 48 as type 1, 31 as type 4, 30 as T8, and the rest of the isolates as various serotypes except types 2 and 6. Most of the T11 strains were the ones isolated from soybean curd.

抄録全体を表示

A great number of papers have been published on mercury residues in rice grains and mercury contents in Japanese human hair. In those papers, however, little attention has been given to the relationship between the mercury contamination in human hair and in rice grains. In this paper it was described that mercury residues in polished and in unpolished rice grains decreased rapidly since 1968 when the use of mercury pesticide was prohibited in rice fields, and were reduced to the back ground levels (0.01-0.02ppm) in 1972. Whereas mercury contents in Japanese human hair showed almost no decrease during the period of twelve years from 1965 to 1976.
Although it is reported that mercury contents in human hair is an indicator of mercury contamination in food, the correlation between the mercury contents in hair and the amounts of daily intakes of mercury was not found In this work. This might be an indication that we should reconsider the toxicological significance of mercury residues in human hair.

抄録全体を表示

海水経由ならびに無機水銀餌料, メチル水銀餌料経由の水銀の取り込みをマダイ・スズキを用いて調べた.
1) 海水からの直接の取り込みは, 飼育開始直後から急速に起こり, 脾・腎への移行が目立った. また, メチル水銀餌料からの取り込みは徐々に起こり, マダイでは腎, スズキでは筋肉部に最も蓄積があった. 無機水銀餌料によるものでは, 両魚種ともほとんど蓄積が起こらず, 塩化第二水銀の腸管吸収率は5%以下と推定された.
2) 塩化第二水銀の形で海水経由, 餌料経由で与えられたものでは, メチル水銀の増加は観察されなかった. 海水中の水銀形態を考えるとき, 魚体中のメチル水銀は食物連鎖によるところが多いと推定された.

抄録全体を表示

1976年10月～1977年3月の間に, 主として東京都中央卸売市場に入荷した生カキ405検体を対象に, それらの大腸菌による汚染状況をECテストにより調査した. その結果, 三陸地方, 三重および広島県産カキはともに検体の50%以上から大腸菌が検出され, そのうち39検体 (9.6%) は230/100g以上の大腸菌による汚染を示し, 中でも広島県産カキの汚染が高かった. また, 12月に入荷したカキは, 他の月のものに比較して高い汚染が認められた.
分離した大腸菌138株のエンテロトキシン産生能を試験したところ, 4株に毒素原性が認められた. そのうち1株はLT産生株で広島県産カキから, 他の3株はST産生株で岩手および三重県産のカキから分離されたものであった. これらの血清型は, LT産生株はO型別不能H2, ST産生株は1株がO25: H42, 他の2株は運動性を欠きO20およびO型別不能であった.

抄録全体を表示

N-Methylcarbamate insecticides, 3-methylphenyl N-methylcarbamate, 3, 4-dimethylphenyl N-methylcarbamate and naphthyl N-methylcarbamate, and their N-nitroso derivatives were tested for mutagenic activity to Salmonella typhimurium TA 98 and TA 100 in the presence and absence of metabolic activation system (rat liver microsomal preparation, “S-9 mix”). The nitroso derivatives were mutagenic for strain TA 100 without S-9 mix but not for strain TA 98, indicating that the nitroso derivatives were potent base-change mutagens. The mutagenic activity of nitroso derivatives for strain TA 100 was found to disappeared in the presence of S-9 mix. Neither strain TA 100 nor strain TA 98 responded to N-methylcarbamate insecticides with or without S-9 mix.

抄録全体を表示

今回, こしょうなどを中心に, 香辛料の糸状菌の分布状況, AF産生が疑われる菌株などについて検討を行った.
1. ガーリックの汚染度は比較的低かった.
2. 七味, 一味では, A. glaucusが主に分布しており, 両試料とも1例から, A. flavusが分離されたが, AF非産生株であった.
3. 粉状こしょうでも, A. glaucusが主に分離され, 1試料ではあるが, 汚染度の高いものが見いだされた.
4. 粒状黒および白こしょうには, A. flavusが主として分布しており, AF産生株が, 粒表面基質から分離きれた.

抄録全体を表示