[in Japanese]

View full abstract

Influence on brain serotonin (5-HT) as a parameter of brain function was investigated when rats were given diets contained amino acid mixture.
The results obtained were as follows:
(1) In the rats fed the diet without competing amino acids, serum total and free tryptophan (Try), brain 5-HT were elevated.
(2) In the rats fed the diet containing half amount of competing amino acids, plasma total and free Try did not change, but free valine, leucine, isoleucine, phenylalanine, and tyrosine levels in plasma decreased, whereas brain Try and 5-HT increased.
(3) In the rats fed the diet added 0.5% Try, total and free Try in plasma, brain Try and 5-HT increased and the competing amino acids except phenylalanine did not change.
(4) In the rats fed 30% fat diet, plasma free Try increased but plasma total Try, competing amino acids except phenylalanine, and brain Try and 5-HT did not changed.
The multiplecorrelation coefficients between brain Try and plasma total Try and plasma total Try with competing amino acids were higher than the correlation coefficients between brain Try and plasma free Try.
This result suggests that brain Try and 5-HT turnover were influenced by plasma total Try and competing amino acids but not by plasma free Try.
It's presumed that difference of amino acid composition in food influences quickly and complicatedly on brain 5-HT concentration, and that effects of diets on usual brain function are important.

View full abstract

The present study was focussed on examining the influence of reproductive function in rats kept in lamp light and continuous darkness conditions with different dietary tocopherol respectively (Toc-supplement group, Toc-nonsupplement group). dl-Alpha-tocopheryl acetate was used for the dietary tocopherol. Male rats of Sprague-Dawley strain were fed the diets for 45 days. The following are results of our experiment.
1) The weight of the accessory reproductive organs were significantly decreased in Toc-nonsupplement group under continuous darkness condition, but the decreasing was restrained in Toc-supplement group under continuous darkness condition.
2) It was not observed that growth of spermatocyte and spermatid in Toc-nonsupplement group under lamp light and continuous darkness conditions. On the other hand, it was observed in Toc-supplement group under lamp light and even continuous darkness conditions.
3) Total-tocopherol in plasma of rats kept in continuous darkness condition was realized tendency of the decreasing.
4) From these results, it was suggested that alpha-tocopherol have influence on maturity of the genital organs of rats which were restrained by continuous darkness condition.

View full abstract

In regard to inhibition with polyphenols against formation of the strong carcinogenic nitrosamines, the reaction of nitrite with polyphenols, especially catechol, was studied in relation to their browning reaction.
1. Polyphenols reacted comparatively rapidly with sodium nitrite, causing remarkable browning. The rate of browning decreased in the order of gallic acid>tannic acid>pyrogallol>catechol>p-benzo-quinine.
2. The reaction of sodium nitrite with catechol was accellerated at a strong acidic pH range (pH 2.0 and pH 4.0) and caused an intense browning color followed the rapid decrease of sodium nitrite.
3. The browning reaction products of sodium nitrite-catechol system was fractionated by Sephadex G-25 column chromatography into three components. The formation of the reducing browning reaction products showing absorption UV range and the reducing ability to the 2.6 dichlorphenolindophenol was reconfirmed from the results of paper chromatography.
4. Catechol inhibited the formation of nitros dimethylamine in the reaction of dimethylamine and sodium nitrite.

View full abstract

A modified starch, dicarboxyl starch (DCS), was prepared from potato starch by periodate oxida-tion following chlorite oxidation. The compound had the binding ability to metals in vitro. Under the lower nutritional level (10% casein and lower level of calcium and phosphorous), rats were fed with diets containing strontium or cadmium with or without DCS for several weeks. The growth rates of rats fed diets containing cadmium (0.005 and 0.02%) seemed to be improved by the addition of DCS. Strontium concentration in the tibia and cadmium in the liver were decreased by the addition of either 2 or 3% DCS to the diet. Strontium concentration of the tibia of rats fed the strontium diet without DCS was significantly higher than that of rats fed the strontium diet with DCS. These results indicate that DCS added to diet seemed to prevent the intestinal absorption of strontium or cadmium in rats.

View full abstract

Selenium (Se) contents of Japanese foodstuffs were measured by neutron activation analyses with the TRIGA-II reactor in Atomic Energy Research Laboratory, Musashi Institute of Technology. Freeze-dried samples (200-500mg) were irradiated in the pneumatic tube (thermal neutron flux, 1×10¹²n·cm^-2·sec^-1) for 10sec, and ^77mSe produced was counted for 30sec in a γ-ray spectrometer system equipped with a Ge (Li) detector. Samples containing less than 0.05ppm Se and the processed foods of high salt contents were analyzed with radioactivities of ⁷⁵Se after irradiation in the central symble (thermal neutron flux, 4×10¹²n cm^-2 sec^-1) for 5 hours, digestion in the HNO₃-HClO₄ mixture, and then purification by a precipitation process. Foodstuffs of animal origins contained more Se than those of plant origins. Se contents were as follows in the descending order: fish, meats, cereals, vegetables, and fruit. Daily per capital intaked of Se was in the range of 100-200μg, as calculated for and as found by analysis of composite diets representing ordinary Japanese meals.

View full abstract

The two high-quality brands of Chinese green tea, “Pi Lo Chun” and “Hwang Shan Mao Fong”, were investigated for their aroma characteristics. A Japanese green tea sample made from var. Yabukita was used for comparison. Aroma concentrates were prepared from these three samples and analyzed by a combined gas chromatography-mass spectrometry technique; polar and apolar columns were used in the gas chromatography. The result showed that 1-pentene-3-ol, cis-2-pentene-1-ol and pentanol were present in larger quantities in “Pi Lo Chun” than in the Japanese tea and geraniol, 2-phenylethanol and benzylalcohol occurred in much larger quantities in “Hwang Shan Mao Fong” than in the Japanese tea. Both of these Chinese tea brands were characterized by minor contents of linalool, nerolidol and indole which generally existed in the Japanese tea.

View full abstract