The effect of some synthetic food dyes on RNA-synthesizing reaction was studied by employing the DNA-dependent RNA polymerase purified from Escherichia coli. And the modes of inhibition by ponceau 3R and rose bengale were discussed.
Ponceau 3R, ponceau R and orange I strongly inhibited the polymerase reaction at the concentration of 1mM. Among them, ponceau 3R was assumed to prevent the polymerase activity by interacting with the initiating region of RNA-transcription on DNA. The dye, however, showed a weak affinity to DNA.
Xanthene dyes which contained halogen atoms such as eosine, erythrosine, rose bengale and phloxine strongly inhibited the polymerase at 0.1mM. Since acid red showed no effect on the polymerase at higher concentrations, it was presumed that halogen molecule was essential to the inhibitory effect of xanthene dyes. The inhibition took place even in the dark, indicating no essential participation of photo-chemical reaction by these dyes. Rose bengale seemed to inhibit the RNA synthesis by binding with the polymerase molecule.
Naphthol yellow S and indigo carmine gave on inhibition for the polymerase reaction.

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Sodium carboxymethylstarch (Na-CMS) labeled on the position of 2-C carboxymethyl group was prepared, and its 2% aqueous solution was administered to the rat by gastric intubation, and the resultant radioactivity of the solution was estimated at 0.8Ci/ml.
The author found that 5.6% of the radioactivity was expired as CO₂ within 96 hours, 1.8% excreted into the urine and 83% found in the faeces.
The urine was tested by thin layer chromatography using cellulose powder as adsorbent. As the result, three bands were conspicuous to some extent than the others. The first band, which was regarded as Na-CMS contaminated with faeces, was found on the starting line, the second band at the point of the Rf value 0.37 regarded as glucose derivative, and the third band at the point of the Rf 0.67 whose entity was not known.
Na-CMS in the faeces was determined with 2, 7-dihydroxynaphthalene, which was 79.1% of the dosage administered.

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During the period of 1965-69, a total of 90 outbreaks of staphylococcal food poisoning was reported in Tokyo. Of them, 55 cases were confirmed bacteriologically in our laboratory, as those cases showed complete agreement on the coagulase types of the isolates both from incriminated foods and from patients. Incriminated foods of 36 (66%) outbreaks were found to be typical Japanese style processed foods which had been mainly composed of rice, i. e., 17 (31%) outbreaks by Nigirimeshi (rice ball), 8 (15%) by Sushi (rice ball with raw fish), 6 (11%) by Japanese cake and 5 (9%) by delivered luncheon, while the remainder scattered to 8 (15%) by cake, 4 (7%) by baked egg, 3 (5%) by salad, 2 (3.5%) by bread and 2 (3.5%) by other miscellaneous food, respectively. As for the coagulase types of the causal isolates, 14 outbreaks were proved to be caused by the type II organisms, 16 outbreaks by type III, 11 by type VI, and 14 by type VII respectively. Whereas none of the organism belonged to the coagulase types I, IV or V was detected throughout the investigation.

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The distribution of triglycerides constituting various fats and oils was determined by gas liquid chromatography, and it was confirmed that only the distribution of triglycerides in raw milk fat was different from those in other fats and oils.
On this finding, the authors devised a criticism to discern whether ice creams contained foreign fats and oils.
The evaluation was made that when the distribution of triglycerides constituting ice cream fats was similar to that of milk fat, the ice cream fat did not contain other fats and oils except milk fat. On the other hand, the distribution differing from milk fat, it was suggested that the ice cream fat contained foreign fats and oils. In cases of the latter, quality and quantity of foreign fats and oils added to the ice cream were also estimated.

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Several kinds of determination methods of saccharin sodium in foods have been published, but most of them do not base on the specific reaction for saccharin, for example the method of the neutral titration.
In this report, gas chromatographic method for the new determination of saccharin sodium was studied.
The principle of this method bases on the fact that saccharin sodium is converted to thiophenol derivative by the reaction with 1ml of hydrochloric acid and 2g of zinc at 90°C, and it was extracted with 3ml of methyl isobutyl ketone (containing 0.01w/v% pyrene as internal standard) and then injected to Shimadzu (GC-1C type) gas chromatograph. Chromosorb G containing silicone DC-11 (2%) is suitable as the column for thiophenol derivative or pyrene. The relation between peak heights of thiophenol derivative and amount of saccharin sodium was linear in the range of 1-100mg.
This method was applied to fruit juice and canned fruit, into which 500ppm of saccharin was added.
The gas chromatography was not interfered by the components contained in food and the recovery rates were over 97%. The minimum limit of detection was approximately 1 μg as saccharin.

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[in Japanese]

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