This review summarizes our work on some aspects of amino acid and protein metabolism in B₆-deficient rats.
1. Functions of B₆ enzymes of mitochondrial origin, especially aspartate and ornithine transaminases, were studied. The former enzyme was shown to produce aspartate from glutamate efficiently by coupling with TCA cycle. The latter enzyme catalyzed an efficient conversion of α-ketoglutarate, a member of TCA cycle, to glutamate.
2. In rat liver some B₆ enzymes predominantly exist as holoenzymes while others exist as apoenzymes to a considerable degree. The changes of absolute amounts as well as apo/holo ratios of representative B₆ enzymes in B₆ deficiency were studied.
3. Severity of B₆ deficiency in the rats fed 70% or 10% casein diet was compared. Severe deficiency was observed in the rats fed 70% casein diet as evidenced by a retardation of growth, and decreases in pyridoxal content and enzyme activities in the livers.
4. Metabolic disorders were studied in the rat fed the 70% casein B₆-deficient diet. a. In B₆ deficient rats, the changes of hepatic enzyme activities did not necessarily reflect the degrees of impairment of amino acid metabolism. In the deficient animals, metabolism of glycine, serine, threonine and some members of urea cycle was markedly impaired. b. Fatty liver was induced in the deficient rats as a result of accumulation of triglyceride and cholesterol ester.

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The present experiments were carried out in an attempt to investigate the tyramine formation in Koji and Miso with relation to the process of making Miso under aseptic conditions.
Koji was made of steam sterilized rice by inoculation with Aspergillus oryzae and Miso in fermentation process by inoculation of Aspergillus oryzae or lactic acid bacteria into admixtures of boiled soybean with the above-stated Koji. Samples were taken from the Koji and analyzed for tyramine.
Koji prepared by inoculation with Aspergillus oryzae was observed to contain no tyramine, while Koji prepared by inoculation with lactic acid bacteria was found to produce approximately 3mg% of tyramine, which were decreased gradually with time.
In the case Miso prepared by inoculation with lactic acid bacteria, tyramine was also produced in almost the same amount as mentioned above, but calcium carbonate fortified Miso was higher in tyramine content than the control under the same conditions of moisture and sodium chloride contents of Miso.
Furthermore, by the experiments with Miso free from tyramine, the formation of tyramine was found to decrease with increasing concentration of sodium chloride in Miso. But, in the case of Miso with a low concentration of sodium chloride the tyramine formation was increased considerably by addition of glucose and calcium carbonate.

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Since mid-19 century, Wasanbon-to has been manufactured in Japan by a unique traditional refining procedure. The Togi step is based principally upon polishing with water, and pressing-off of molasses the Oshi step. No reports have been published on the substances responsible for the unique flavor of Wasanbon-to.
In the present paper the contents and compositions of the amino acids, the organic acids and carbohydrates in Wasanbon-to were studied by chromatographic techniques. The samples were 1st press-off molasses, 5th press-off molasses and finally refined sugar.
The results are summarized as follows : Aspartic acid was the predominant free amino acid followed by asparagine and alanine. The content of γ-amino butyric acid was 0.88 mg% in the final product. Of organic acids, the content of cis-aconitic acid was 30.89 mg%, making 49.4% of the total organic acids excluding unidentified ones ; Pyroglutamic acid was 11.4% of the total. Glucose, fructose and sucrose was detected and determined by gas-chromatography in the final product.
The refining technique remaines impurities in the products, which appear to contribute to the unique flavor of this traditional sugar.

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Nutrient intake, calory consumption, nitrogen balance, and blood properties were determined in 29 male patients with Duchenne type PMD (6 to 18 years) and by the controls of 12 male tuberculous patients (6 to 15 years) who were hospitalized at the National Tokushima sanatorium.
The heights and body weights of 650 male patients (6 to 20 years), who were hospitalized in 18 medical institutions in all parts of Japan were measured with Duchenne type PMD.
Results were as follows:
1. Although amounts of nutrients ingested by PMD patients were markedly smaller than those under control, there was no difference between the two groups, when amounts were calculated in terms of unit of body weight. PMD patients ingested larger amounts of animal proteins than those under control.
2. The intake and consumption of calory in PMD patients were barely balanced, but the intake was not satisfactory, when the safety coefficient was considered. Moreover, the rate of N accumulation was slightly low.
3. PMD patients had low values in the total blood specific gravity, serum specific gravity and serum urea N in comparison with those under control. Concentrations of free amino acids, particularly essential amino acids, in their bloods were significantly low, indicating that the patients were in the state of so called malnutrition.
4. The growth curves (rates) of heights and body weights of patients, began to decline already around six years of age in comparison with healthy persons, and, particularly in the body weight growth curves, there were marked differences between the two groups before the growth period in puberty, and the gap increased more and more with aging there after.

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Free radical signals were detected on the freeze-dried powder of the nondialysable and dialysable fractions of the melanoidins produced in the enzymatic browning systems of “apple enzyme·catechol” and “apple enzyme·catechol·methionine. ” Notwithstanding the dialysis of the browning systems, the coexistence of methionine in the systems and the reaction time of the enzyme, the g values were 2.004 in all specimens determined when the signal of DPPH had been comparatively determined as the standard of the value, or 2.007 in the case of Mn²⁺ as the standard.
The relative concentration of the radicals in the nondialysable fractions was dependent on the concentration of catechol and the enzymatic activity in the browning systems. The maximum of the relative concentration was observed at early stage of the reaction when the enzymatic activity was much higher.
The relationship between the antioxidative activity of the nondialysable fractions against linoleic acid and the relative concentration of the free radicals in them was suggested.

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Nitrite contents in cow's milk, milk products and human milk were determined colorimetrically at 540 nm by a diazo-coupling reaction with sulfanilamide and N- (1-naphthyl) ethylenediamine dihydrochloride in a slightly acid solution, and nitrate contents were determined as nitrite after reduced to nitrite by passing a cadmium column (1.8 X 10 cm, flow rate : 4.6 ml/min).
Nitrate nitrogen levels in cow's milk varied from 0.2 ppm to 0.5 ppm, but high nitrate levels (1-5ppm) was found in human milk. No nitrite nitrogen (<0.01 ppm) could be detected in cow's milk.

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It is known that pectic substances are hetero polysaccharides constituted with several kinds of neutral sugars besides galacturonic acid.
For the purpose of obtaining basal information on the suitability for cooking and processing of pectic substances, we examined constituent sugars of pectic substances extracted from 20 kinds of fresh fruits and those of 4 kinds of commercial pectin.
The contents of anhydrogalacturonic acid in the pectic substances from fruits were 26.2% in banana pulp, 36.9% in banana peel, 38.8% in loquat and 39.8% in Japanese persimmon, while those from the other fruits were 50.4 to 74.7%.
The fractionation of neutral sugars by liquid chromatography showed that the amounts of neutral sugars contained in each pectic substances were variable, but their kinds are almost similar. Arabinose or galactose was the largest in amount. The next largest ones were rhamnose and xylose. Mannose was very small in amount and the ribose amount was a trace. No constant result was obtained with glucose.

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Trial manufacture of POV and TBA test papers for detecting lipid oxidation was attempted. One drop of oxidized oil is placed on the POV test paper and let stand for one min. Then the paper is put into water, and blue color appears depending on the oxidation degree. On the TBA test paper, one drop of oxidized oil and three drops of water are placed. The paper is heated under infrared lamp for 5 min, and pink color is developed.

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