The current paper attempts to review the studies on plastein synthesis reaction, with emphasis on its applications in the food and nutrition area. This reaction is known as an enzymatic process in which, reverse to the conventional proteolysis, a peptide mixture grows to polymerize under an unconventional condition of incubation, with formation of the so-called plastein. A topical finding has been made that almost arbitrary amounts of amino acids can be incorporated during the plastein reaction when they are esterified on use. It is thus possible to enhance the essential amino acid levels of food proteins. Their eating qualities also can be generally improved through the plastein reaction. Significance of this enzymatic process was discussed in special relevance to the peptide nutrition in animal and also to the food utilization of protein resources.

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Nutritive values of raw Euphausia superba (E. superba) protein concentrate, raw E. superba powder and preboiled E. superba powder were compared with that of whole egg protein in rats and the following results were obtained.
(1) Average weight gains of rats fed with raw E. superba protein concentrate and preboiled E. superba powder were not significantly different from that of rats fed with whole egg protein. On the other hand, the group fed with raw E. superba powder showed a slightly lower growth than those fed with whole egg protein.
(2) Biological value, digestibility and not protein utilization of raw E. superba protein concentrate fed group closely resembled to those of whole egg protein group. But, raw E. superba powder and preboiled E. superba powder groups obtained low values in comparison to whole egg protein group.
(3) A/U×intake protein value in the raw E. superba protein concentrate group was similar to that of whole egg protein group. Moreover, raw E. superba powder and preboiled. E. superba powder groups gave low values significantly different from that of whole egg protein group.
The above results indicate that the E. superba protein has a good quality.

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The effects of sex hormones on the development of the alcoholic fatty liver were studied on the castrated rats with or without compensatory administration of the sex hormones.
Groups of Wistar rats were fed for a defined periode on a commercial stock diet (obtained from Oriental Company, Japan) and castrated. At 30 days after the castration ethanol was given by a stomach tube (6g/kg body weight) following the administration of testosterone, estrogen or progesterone. The amount of neutral fat and glycogen in the liver, and nonesterified fatty acids (NEFA) and glucose in the blood were estimated. The results obtained are summarized as follows:
1) In castrated male rats the administration of testostrerone increased the amount of neutral fat in the liver and improved the lowering action of the castration on the alcoholic fatty accumulation. In female rats the administration of follicular hormone repaired depressive effect of the castration on alcoholic fatty accumulation.
2) In castrated male rats the lowered level of NEFA in the blood seemed to be nearing the value of the control after the administration of testosterone. Progesterone raised the level of NEFA in the blood of female rats.
3) The amount of glycogen in the liver was decreased by the administration of ethanol in both male and female rats.
4) The blood sugar was decreased by the administration of ethanol in both sexes.

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Authors have reported the physiological roles of anserine (β-alanyl-N^π-methylhistidine) and carnosine (β-alanyl-histidine) by the experiments using male rats. In this paper it was shown that the contents of anserine and carnosine in the gastrocnemius muscle were not affected by testisectomy or adrenalectomy, but anserine decreased remarkably to 1/2 levels of that in control group and carnosine decreased slightly by the thyroidectomy. Effects of thyroidectomy were completely restored by thyroxine administration to the thyroidectomized rats.
Changes in these dipeptide contents in the gastrocnemius muscle were examined on rats fed diets containing several protein (casein) levels for 2 weeks. β-Alanine and carnosine contents in muscle were decreased remarkably by feeding the low protein diets (0%, 5%), whereas they were maintained on normal level by the high protein diets. Although the dietary protein levels did not show any influence upon the anserine content, urinary N^π-methylhistidine in rats fed 60% protein diet increased three-fold as compared with that in control group.
From these results it was suggested that anserine and carnosine contents in muscle were metabolically controlled with the close relation to dietary protein level as one of the external factors and to the thyroidal balance as one of the internal factors.

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1. A significant correlation between the Rohrer index (Y) and skin fold thickness (X) was found in 240 male patients with Duchenne type PMD (r=+0.748, p<0.001). The regression line was Y=2.449X+71.945.
2. Judging by the extent of deviation from the means of Rohrer index, 17.1% and 17.4% of the patients were obese and emaciated, respectively on 650 PMD patients.
3. To determine the favorable physique of the patients, the Rohrer index was examined in relation to the stages of disease, degrees of scoliosis or of deformity in lower extremities, vital capacity, and creatine phosphokinase activity in serum. Patients having 10% to 20% more indexes from the mean showed the least disorders.
4. Body weights on one month before death, were investigated on 159 patients in connection with the cause of death. Most patients lost their weight markedly and tended to die from the infection, while far less numbers of the patients were still obese and had a tendency to die from heart failures.

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The fatty acids distribution of triglycerides (TG) of human milk fats in Canada has been known. However, little knowledge has been obtained on TG of human milk fats in Japan. So TG extracted from Japanese milk (mature milk and colostrum) and infant formulas were subjected to stereospecific analysis.
1) In spite of the difference of fatty acids composition of human milk fats among Japanese and Canadian, fatty acids distributions of TG of both milk fats were similar. That is, the fatty acids composition of positions 1, 2 and 3 was not random. C_14:0, C_16:0 and C_16:1 were preferentially esterified with position 2 (p-2) of TG. On the other hand, the unsaturated acids of C18 were not esterified with p-2, but with position 3 (p-3). C_18:0 of mature milk was associated with position 1 (p-1). C_18:0 of colostrum, although it showed some scatter, was found in p-3. The short chain fatty acids such as C_10:0 and C_12:0, were mainly esterified with p-3.
2) The TG extracted from colostrum contained more C_16:0 and less C_18:2 than those of mature milk. However, there was no remarkable difference of stereospecificity between colostrum and mature milk except C_18:0.
3) The TG of infant formulas' fats extremely differed from those of human milk fats. The amount of C_16:0 at p-2 was small (22%), but that of C_18:2 was large. C_12:0, it was abundantly contained in infant formulas' fats (13%), was found in p-2. C_16:0 and C_18:0 were preferentially esterified with p-1. C_10:0 and C_16:1 were associated with p-3. The seresults indicate that it is necessary to change the distribution of fatty acids in infant formulas' fats for improvement of the absorption of those fats in infants.

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Studies were conducted to detect and identify proteinase inhibitors in rice bran. Water extracts of rice bran exhibited significant inhibitory capacities against trypsin (EC 3.4.21.4) and pepsin (EC 3.4.23.1), but little and practically no inhibitory capacities against α-chymotrypsin (EC 3.4.21.1) and elastase (EC 3.4.21.11) respectively. The trypsin inhibitor appeared to be a thermolabile proteinaceous substance which was relatively abundant in the germ portion. The pepsin inhibitor distributed relatively evenly over the whole bran fraction, and was a highly thermostable substance containing phosphorus in its molecule.
Kinetic analyses of pepsin inhibition by the water extracts of rice bran revealed that the inhibitor combines with the substrate protein so rendering the protein poorly available for the peptic action. Dispersibility of the substrate protein, measured in the media of varied pH, was found to be significantly lowered by the added bran extracts especially under the pepsin assay conditions. Authentic phytate showed essentially the same effect on the protein dispersibility as observed with the bran extracts. Pepsin inhibitory capacities of cereals and soybean paralleled with their phytate contents. These results and other considerations lead to the conclusion that phytate is a factor which accounts for most of the pepsin inhibition by the bran extracts, and also suggest the possibility that the inhibition by phytate may be of some nutritional significance in animals that consume relatively large amounts of phytate.

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Euphausia superba has been studied by many workers due to its importance as a new protein source.
Composition, ecology and processing method as well as its catching have been widely reported. Further Euphausia superba's practicable utility is also understood and its products are made available. Authors are actively engaged in research on this important species, and the present paper reports the results of Euphausia superba protein extractibility, main characteristics of its protein including amino acid composition, and artificial digestibility.
Euphausia superba obtained from Antarctic Ocean was freezed on board immediately after catching. The protein from Euphausia superba was extracted using 0.05% NaOH. This protein showed very similar amino acid pattern to that of whole egg protein. Disc electrophoresis data of Euphausia superba protein was different from that of prawn protein. Artificial digestibility tests of Euphausia superba protein conducted with pepsin, showed similar digestibility with that of whole egg protein.

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