Of the analysis method for the neutral amino acids, two dimensional chromatography is very commonly used. But, this method is not so convenient, for it takes a long time to obtain the results. In our recent reports, the investigation was made on the determination of basic amino acids; lysine, arginine, histidine, by using highvoltage-paper electrophoresis method. In this paper, owing to its advantage, we tried to use highvoltage-paper electrophoresis on one side of the two dimensional chromatography for the separation of neutral amino acids so as to shorten the time requiring for this procedure. As the results of the experiment, a clear diagram of separated 11 neutral amino acids, except leucine and iso-leucine was obtained with in a half period of usual procedure.
Endurability to the cold became an urgent problem in the South Polar Expedition, and many universities and institutes therefore took up collaborate investigations on this subject in order to establish the most pertinent method for estimation of human tolerance to the cold, consequently contributing to physiological appraisal of the above problem. Though a large number of experiments were conducted from both physiological and biochemical view points, it was first confirmed from the work alloted to us that variation of energy metabolism serves as a good methodology for this purpose. Furthermore, as skinfold thickness has an inverse proportional relationship to energy metabolism we have reached the abbreviate conclusion that higher skinfold thickness results in higher endurability to the cold.
In the previous report the quantity and quality of fats and oils consumed by the ordinary households were surveyed in Tokyo and the neighboring cities. The survey was expanded on the patients of hypertension, and this time 18 elderly men and women who had been suffering from the hypertension were the subjects of the survey. Their daily fat intake calculated from the recipes recorded by them was on an average 32.5g, which was higher than that of all Japanese average(The National Nutrition Survey), and the ratio of fat calories to total calories was 17.3%, which was also higher than other surveys. Of all the fat intake the proportion of animal fat and vegetable oil was 6:4, and this ratio was reverse in case of Japanese average. The pure fats and oils were consumed about 10g a day a person, and vegetable oil occupied as much as 70%, but of the total ingested fat the animal foods were the main sources. The composition of the fatty acids of the fats and oils ingested by these patients was also investigated because the quality of the fatty acid is said to have much to do with hypertension and other heart diseases. The important saturated fatty acids, palmitic and stearic were 26%, whereas the unsaturated fatty acids, oleic, linoleic and linolenic were 22% in all.
The previous papers have reported that the vegetable oils generally have no rising effect of serum cholesterol level, moreover safflower, corn, sunflower oils lowered distinctly its level. In this report the rice oil which expression is specially conducted abundantly in Japan is put to the test. The rice oil showed a remarkable lowering effect supposed much more than three kinds of oils above mentioned. This effect may be attributed to its unsaponifiable matters, because its linoleic acid content is only 36% that is much less than the other oils' and the cholesterol lowering effect of the rice oil is different by the refine methods.
As a part of a series of studies on the surface activation of medicinals, higher alkylsulfates of l-lysine were synthesized. In this report, physicochemical properties of these compounds were investigated from the view point of pharmaceutical preparation. With increasing number of carbon atoms in the alkyl group, the salts become sparingly soluble in water at room temperature, displaying Krafft's phenomenon, one of the characteristics of ionic surfactants, showing a sudden elevation of solubility at a certain temperature. They form a micelle in aqueous solution and indicate a strong surface activity. They were stable and less hygroscopic in the form of powder. They were found to have more efficiency of emulsification and solubilization for fatty-soluble vitamin than that of sodium alkylsulfate.
Investigation was made on the physicochemical properties of thiamine disulfide (TDS) dialkylsulfate from the view point of pharmaceutical preparation. They form a micelle in aqueous solution and indicate a strong surface activity as well as thiamine dialkylsulfate. With increasing number of carbon atom in the alkyl group, the salts become extremely sparingly soluble in wat er at room temperature, but due to their surface activity they are easily dispersed in water as fine particles, and become soluble in some organic solvents, such as alcohols and chloroform. It was shown that TDS dicetylsulfate is stable in a suspension not only in acidic environment, but in weak alkalin. The powder of TDS dicetylsulfate is very stable even when mixed with vitamin C or calcium carbonate. The blood total thiamine levels after oral administration of TDS dicetylsulfate or its related compounds were determined using rabbits and it was found that TDS dicetylsulfate was more absorbable than TDS or thiamine hydrochloride.