Isolation and purification of protein from bacterial cells (Alcaligenes sp.) which had grown on nparaffin were investigated with the purpose of utilization of microbial cell protein for human food.
Protein was extracted with 2% NaOH from the dried cells. Protein isolates obtained from the extract by isoionic precipitation and following lyophilyzation showed a similar pattern of essential amino acids to that of the dried cells except for methionine, the content of which significantly decreased in the protein isolates. The first limiting amino acid was the sulfur containing amino acids for the both cases. In vitro digestion test by pepsin showed an increased digestibility of the protein isolates, which neared that of milk casein.
Dialysis of the alkali extract against water resulted in removal of an unpleasant odor and elimination of the cell wall materials. Protein fractions were isolated from the dialyzate by addition of calcium salt and the following dialysis against water, the ethanol precipitation and the isoionic precipitation. The protein fractions of high purity were obtained in relatively good yield by those simple procedures.

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Studies reported here were undertaken to determine the feasibility of producing for human food a protein isolate from rice bran. Various extractants and conditions were evaluated for effectiveness in solubilizing and recovering the protein of the defatted rice bran. As the result of the evaluation, the following isolation process was determined to be very effective: (1) The defatted rice bran is stirred with 20 times volumes of 0.05% NaOH for 2 hrs. at 37°C. (2) The solubilized protein is recovered from alkaline extracts by isoelectric precipitation at pH 4.5 to 5.0. (3) The precipitated protein is soaked with 85% ethanol for 1hr. at room temperature and freeze-dried.
The above process yielded an odorless protein isolate of a very light-gray color and 94 to 99% protein (dry basis) which has excellent essential amino acid pattern and high digestibility. About 30 to 40% of total crude protein in defatted bran is recovered as the protein isolate.

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Changes in content of free amino acids in kidney bean seeds and their etiolated seedlings were studied. Amino acids and peptides were separated by two dimentional thin-layer chromatography, and then amino acids separated were determined by the Yemm and Cocking's ninhydrin method. The determination of pipecolic acid was made by the modified method of the Schenk's, based on the reaction with ninhydrin under acidic condition.
By the immersing the seeds overnight in the water, the content of pipecolic acid increased apProximately two times as much as that of dry seeds. From 3 days germination, pipecolic acid content was kept constant, and decreased gradually in the cotyledons and increased in the young plants.
Several unknown ninhydrin positive spots were obtained on the chromatograms. One of which produced pipecolic acid after acid hydrolysis, and other two of which produced glutamic acid after mild hydrolysis.

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1) The lipid contents of various organs of mice were examined. The phospholipid contents were considemably different between them and decreased in the following order: brain, liver, kidney, lung, intestine and muscle. The neutral fat contents decreased in the following order: limbic muscle, kidney, abdominal muscle, brain, intestine, lung, spleen and heart.
2) Generally speaking, fatty acid composition of neutral fat, with exception of brain, showed the similar tendency between them. The content of saturated fatty acids was larger in lung than in any other organ.
3) Organs of mice examined could be classified into the following three groups on the basis of the distribution pattern of fatty acid in phospholipids.
1. heart, limbic muscle, abdominal muscle, liver, kidney and intestine
2. lung and spleen
3. brain
Lung and spleen were divided from the first group by their high palmitic and low linoleic acid contents.
The fatty acid composition of brain was much different from those of the former two groups.
4) The exsistence of a polyunsaturated acid, docosahexaenonic acid was verified in the several organs, especially heart, limbic muscle, kidney and abdominal muscle.

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The protein content of nonglutinous and glutinous upland rice grains of 45 varieties from the Ibaraki Agricultural Experiment Station (experiment I) and of 47 samples of 19 varieties purchased by the government (experiment II) was determined. There was no difference in protein content between the nonglutinous and glutinous types. However, the results showed that the upland rice grains were high in protein content. The average protein contents of the grains on dry weight basis from experiment I and II were 11.52 and 11.82%, respectively.

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Six kinds of soybean milk were prepared by extraction of soybean immersed in water for thirty minutes at 50, 60, 70, 85, 100 or 120°C, respectively. Control soybean milk was prepared without heating and the effect of heating on the physicochemical properties of protein in soybean milk was studied, comparing the results with those obtained by heating of skimmilk.
1. It was observed by use of electron microscope that protein particles of soybean milk tended to aggregate at lower heating temperature forming giant particles above 100°C, than those of skimmilk.
2. On higher heating temperature the increase of acid-soluble nitrogen compounds was observed both with soybean milk and skimmilk.
3. From the study on the effect of heating on centrifugal sedimentation (6, 590 X g) of nitrogen Compounds, it became clear that on heating between 50-100°C, 20-50% of total nitrogen of soybean milk was present in the sediment. Heating to 120°C caused a remarkable increased in the rate of total nitrogen sedimentation. Similar tendency was observed with skimmilk.
4. The rate of trichloroacetic acid-soluble nitrogen in acid-soluble nitrogen compounds was larger with soybean milk than with skimmilk.
5. The soluble and insoluble fractions in saturated magnesium sulfate solution were found to decrease in both soybean milk and skimmilk with higher heating temperature. With heating above 100°C, these fractions disappeared wholly.

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This experiment was performed to investigate the possible difference in protein metabolism between conventional and germfree rats. First, the concentration of free amino acids and protein in plasma were determined in germfree rats as well as in conventional ones. The both groups were trained to take diet quantitatively within one hour.
The total free amino acid level in plasma of the conventional rats was higher than that of the germfree at 3, 5 and 18 hours after feeding, and reached the same level after 24 hours. Forty-eight hours after feeding the plasma total free amino acid level of the conventional rats was lower than that of the germfree rats. The highest concentration of total free amino acids in plasma was obtained in both groups at 5 hours after feeding. The time curves of individual amino acid levels in plasma differ from each other, but in respect to the same amino acid from both groups a similar trend in the plasma level change was observed. At 3 hours and 5 hours after feeding the molar ratio of arginine, proline, alanine, leucine and tyrosine of conventional to germfree rats was higher than that of glutamic acid and phenylalanine. Glutamic acid level in plasma of conventional rats was found nearly the same as that of germfree. Phenylalanine concentration in plasma was significantly lower in conventional rats than in germfree ones.
The difference between the total free amino acid levels at 5 and 24 hours after feeding was significantly greater in the conventional rats than in the germfree.
Protein concentration in plasma also increased after feeding in both groups, but the germfree rats showed lower protein concentration than the conventional ones throughout the experiment.
Stomach and liver weight of the conventional rats were heavier than those of the germfree ones. The ratio of stomach and liver weight to body weight was also higher in the conventional rats than in the germfree ones.
As mentioned above some differences were observed in amino acid metabolism between the germfree and the conventional rats, but the significance of the differences is not obvious.

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A new method for the estimation of the available iron within the foodstuffs was developed, the principle of this method was based on the solubilization of food's iron by means of the successive digestion by the artificial gastric and intestinal juices.
The digestion of the protein contained was also watched in the same experiments simultaneously. The ratio of the iron extracted by this method from food to the total iron was examined with 16 kinds of foodstuffs, which are taken daily in Japanese meals. The average extraction ratios are 42.0% for iron and 61.0% for protein. When the ratio of this extractable iron to the total was ranged in the decreasing order, this is as follows: fish, soy bean products, green vegetables, livers and animal meat. The least ratio was gained with egg yolk. The amount of iron which can react directly against ophenanthroline in the presence of thioglycolic acid is measured with the homogenates of these foodstuffs. The average percentage of this to the total iron content is found to be 67.4% with the above mentioned 16 kinds of food.

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Both male and female adult rats were fed ad libitum on a methionine-deficient diet containing 20% performic acid-oxidized casein.
Amino acid composition of skeletal muscle protein was determined after 24 days of feeding.
Only few of variations in the amino acid composition were observed as compared with the controls fed on 20% casein, except that of tyrosine and tryptophan which was slightly decreased.
The lysine content in the protein-deficient rat was lowered as has been suggested by several investigators, while none of variation of the basic amino acids was observed in the methionine-deficient rat.
A peculier phenomenon was also noted that the body weight of female rats was not recovered even after the supplement of methionine to oxidized casein;

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The enzymic activity of Galactose-1-phosphate uridyl transferase in the liver which plays an important role in galactose metabolism is large in the period of suckling and decreases with the depletion of milk. In order to elucidate the mechanism of this physiological change of the enzyme, the following experiment was performed.
From the assumption that the induction of the enzyme may occur by galactose which is contained in milk, galactose was given to albino rats of various stages of developments. The enzymic activity, however, did not show any significant changes. The effects of adrenocortical hormone, cortisone and hydrocortisone on the enzymic activity in the period of suckling was remarkably decreased by the administration of the hormone but was not influenced by the hormone in the periods of weaning and depletion of milk.
On the other hand the blood concentration of the hormone is low in the period of suckling, and increases with the process of development. Therefore, it is well considered that the changes of the enzyme in the liver with depletion of milk is controlled by the adrenocortical hormone. Galactose-1-phosphate (Gal-1-P) uridyl transferase

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It was devised to estimate the freshness of muscle by thin-layer chromatography, using K value which has been proposed by T. Saito et. al., in 1959.
K=B/A X 100
A: original optical density of perchloric acid extract of muscle
B: sum of optical densities of inosine and hypoxanthine eluted
Separation of inosine and hypoxanthine from nucleotides in acid extract of muscle was made on thin-layer chromatography and elution from it was in excellent recovery.
This technique is found to be more convenient than that of ion exchange chromatography. For the application of this methad, only a little amount of muscle extract (0.016-0.024ml of equal valume acid extract of wet muscle) was proved to be sufficient, and the K value estimated by thin layer chromatography was also proved to coincide with that of ion exchange chromatography.
The freshness of various kinds of muscle was successfully estimated by this method.

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The effects of vitamin E deficiency, produced by linseed oil on degenerative changes of the kidney and testes in rats was investigated along with other deficient signs.
NaCl fortification under vitamin E deficiency was also studied to find whether NaCl could promote renal damage or not.
Young rats were subjected to three diets, a basal ration deficient in vitamin E (B. R.), B. R. +50mg dl-α tocopherol per week, BR. +2.5% NaCl for 10 weeks.
All animals exhibited renal abnormality, and the deficient animals were more severely affected. No abnormality could be observed in the testes. Vitamin E deficient signs such as organ enlargement, sharp renal autolysis, elevated erythrocyte hemolysis and creatinurea were observed with a high water intake and other side-effects of linseed oil. There was the tendency of a sharp decrease in lecithin and sphingomyelin with an increase in cephalin in kidney phospholipids, and an increase in the testes sphingomyelin fraction.
NaCl fortification, unexpectedly, gave somewhat satisfactory results in initial growth, hemolysis, creatinurea and water intake. However, renal lesions were more markable than the other groups. The renal phospholipid pattern except cephalin which further increased was closer to the control animals but the lecithin content was still low.
Vitamin E, under this condition, partially protected against linseed oil toxicity.
Vitamin E deficiency appears to cause a decrease in tissue lecithin thus leading to degenerative changes.

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The effect of the intake of ‘Konjac’ powder on human serum cholesterol level was examined. Sixteen students (girls) and three patients were selected as the experimental subjects, and these students were divided into three groups following their daily serum cholesterol level. To A and B groups, ‘Konjac’ powder (12g per day) and butter (70g per day) were supplied for four days, while to C group, only ‘Konjac’ powder was supplied for the same period, to the patients, 3g of ‘Konjac’ powder were supplied for about one month.
The results were as follows: 1) The intake of 70g of butter per day increased the serum total cholesterol level. 2) The intake of ‘Konjac’ powder decreased gradually the cholesterol level, and, in case of the patients, after the termination of the ‘Konjac’ powder administration period, the state of decrease was retained for a while. 3) The ratio of esterified cholesterol to total cholesterol was not influenced by this administration.

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Seven kinds of grains (polished rice: Pr, polished barley: Pb, wheat: W, dried KUKSOO: Dk, bread: B, buck wheat: Bw, Italian millet: Im) and 3 kinds of legumes (soy bean: Sb, small red bean: Srb, small green bean: Sgb) were dried at low temperature and pulverized so as to pass the 40-60mesh. They were then hydrolyzed with barium hydroxide or hydrochloric acid for 6 to 8 hrs. (Try) at 120°C, kg/cmcm². After that, 8 kinds of essential amino acids were determined with Leuconostoc mesenteroides P-60, Lactobacillus arabinosus17-5 andStreptococcus faecalis R by means of micro-bioassay, obtaining the chemical score of each food, and then the amino acid pattern similarity was calculated. The following are the results of the improvement in the chemical score by mixing different foods with polished rice and wheat.
The greatest quantity of total essential amino acids was found in Im (2997mg/Ng), followed by Srb, Sb, Pr, Bw, W, Pb, Dk, B, and Sgb.
The chemical score was the highest in Pb (66%), followed by W, Pr, Bw, Dk, B, Srb, Sb, Im and Sgb. Limiting amino acids were determined to be lysine (Pr, W, Dk, B, Im) and methionine (Pb, Bw, Sb, Srb, Sgb).
As to the amino acid pattern similarity between these foods and the egg (the ideal food form) it was found that the similarity was greatest in Bw (0.98) followed by W, Im, Pr, Dk, Srb, Pb, B, Sb, and Im (0.88) being the least similar.
Regarding foods mixed for the purpose of improving the chemical score, the greatest improvement was obtained, from 61 (Pr) to 75, when Pr and Sb were mixed in the ratio of 90%: 10%, and from 61 (Pr) to 73 when Pr and Bw were mixed in the ratio of 80%: 20%, but no significant improvement was seen in mixing Pr and Im. An improvement, from 62 (W) to 64, was obtained when wheat and Sb were mixed in the ratio of 90%: 10%.

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