Peanut protein extracted with tris-citrate buffer (pH 8. 60) was investigated by starch-gel electro-phoresis in the discontinuous buffer system (pH 8. 60) of 0.076M tris-citrate for the gel and 0.3M borate-NaOH for the electrodes, and following results were obtained.
1) Four bands were detected when used the gel without urea and mercaptoethanol, the dissociating agents, whereas more and clearer bands occurred as the concentration of urea increased in the gel, consequently ten-odd bands in the presence of 5M urea and 0.02M mercaptoethanol.
2) Electrophoresis was carried out on 34 varieties of Virginia, Spanish and Valencia types using the gel containing 5M urea and 0.02M mercaptoethanol. Similar electrophoretic patterns were obtained in same types, respectively, with few exceptions. However, the difference inthe pattern was found between Virginia and Spanish-Valencia groups.
3) The above difference occurred between the arachin fractions of the two groups, whereas the conarachin fraction gave identical pattern of all varieties.

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Iron deficient rats (from Donryu strain) were prepared by feeding of iron poor diet for two months. The rats fed on the iron poor diet+deionized water became within this period: body weight 526±4.5→ 201.2±29.3g, hemoglobin 11.6±1.2→9.7±1.5g/dl and liver nonhemin iron 11.6-15.1μg/g. The control rats fed on the iron poor diet+iron supplemented drinking water grew as follows: body weight 52.1±4.7→228.4±32.0g, hemoglobin 11.6±1.2→15.4±1.4g/dl and liver nonhemin iron 112.6μg/g.
The rate of iron absorption was assayed after the administration of FeSO₄ which was given in ten doses of 0.3mg Fe per os. Intestinal absorption of ⁵⁹Fe given with the first dose of iron was 30.8-43.4% in the iron deficient rats and that of control animals was 7.8%. Hemoglobin value of the iron deficient rats recovered to 12.5-14.6g/dl, but the value of the control showed few change. Accumula-tion of liver nonhemin iron increased in iron deficient rats. From these results the following equations were calculated between hemoglobin values (x g/dl) and percentage of iron absorption (y) : y=10895x-2.579, and between hemoglobin values (x g/dl) and liver nonhemin iron (y μg) : y=2.032×10^-4x^5.413.

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Male adult rats were starved for 0 (control), 4, 8, 12 days and period for death (22 or 26 days). Contents of deoxyribonucleic acid, ribonucleic acid and nitrogen in muscle of paired hind limbs and liver, and amount of urinary nitrogen were determined at the end of experimental period.
Total DNA contents of the muscle and the liver were not affected by starvation for 4, 8, or 12 days, but these values of the muscle and the liver decreased by 6% and 28% respectively in the rats which were starved till the death. This result suggests that in skeletal muscle, DNA serves as a suitable reference standard for tissue analysis when animal is not starved till the death. RNA to DNA ratios in the muscle and the liver decreased rapidly at the first 4 days on starving, during the proceeding 8 days these values decreased rather slowly, and just before the death these values seemed to decrease more rapidly than the first period. Changes in nitrogen to DNA ratios of the muscle and the liver were nearly parallel to those found for RNA to DNA ratio.

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Paddy, brown and polished rice grains, respectively, packaged with a plastic laminated film, were stored over a year in the water of Lake Biwa. The chemical and biological changes during the storage period were analyzed and compared with those of rice grains stored by the conventional method at an atmospheric temperature.
The water proofness of the laminated film under the grain storage conditions, i. e. in the water for a relatively long period, was proved to be highly satisfactory; increment in the moisture content of the grains after one year storage period was lesser than 0.5% in every case. Chemical composition of the grains stored in the water were almost similar to those of the grains in the store house of controlled low temperature. The under-water storage prolonged the storage life of the grains. Original freshness of the grains even after the prolonged under-water storage was evidenced by the facts that considerably higher biological activities such as germinative capacity, and catalase and peroxidase activities were detected for the grains stored in the water than those kept in the atmospheric conditions.
Palatability of the grains stored in the water was found satisfactory. Strength of stale-flavor as determined by the amount of volatile carbonyl compounds, rheological characteristics as measured by texturometric indices and cooking qualities as revealed on boiling, showed that the deterioration pro-ceeded in considerably lower rate for the grains stored in the water than those of the atmospheric storage. Cooking rice prepared from the grains stored in the water for the period of 7 months, as judged by 18 panels, were almost similar to those stored at controlled low temperature, in views of its appearance, aroma, taste, adhesiveness, hardness and overall remarks.
As to the atmosphere within the bags of the laminated film, carbon dioxide enriched one was found more effective than air one in preventing the changes in chemical compositions, in lowering the diminu-tion of peroxidase activity, and in retarding the development of stale-flavor.

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Reactions between Ca and casein were investigated at Ca concentrations ranging from zero to ten mM. α_s-Casein began to precipitate at Ca 3 mM and was completely stabilized by κ-casein. κ-Casein tended to aggregate randomly in the presence of 5 mM Ca. S_{20, w} values were 14.4 and 1.8 for κ-casein and α_s-casein, respectively, in the absence of Ca. Caseins were found in gel filtration to be brought into polymerization at such low Ca concentrations that no aggregated particles were visible. α_s-^κ Complex did not grow as fast as α_s-casein did in the presence of Ca. The amounts of Ca bound to caseins were determined at pH 7 and 8 in the presence of 1 to 10 mM Ca using the followings; equilibrium dialysis, gel filtration and centrifugation. The minimum amount of Ca to be necessary for the initiation of α_s-casein precipitation was about 12 moles per mole casein. Weak adsorption of Ca, due to some structural factor, was indicated since the amounts of bound Ca obtained by centrifugation were remarkably lower than those determined by the other methods. The states of bound Ca were studied by gel filtration of ⁴⁵Ca-caseinates with an eluant containing no Ca. More Ca was bound to the α_s-^κ complex in the early stage of the reaction than to the same quantity of α_s-casein only. But the amount of Ca bound to the complex did not vary with reaction time while that bound to α_s-casein increased greatly accompanied by the progress of polymerization. The binding intensity of Ca in κ-casein was so weak that only a small amount of Ca was eluted together with κ-casein in the gel filtration of Ca-κ-caseinate.

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κ-Casein was chemically modified in various ways. Modified groups include the followings; NH₂ group, COOH group, tyrosine, tryptophan, lysine, SH group, serine, histidine, arginine, and methionine. These groups and residues were probably not completely modified, because κ-casein was not dissociated into single molecules under the conditions used. Normally κ-casein has an S_{20, w} of about 14, which decreases to about 3 when dispersed by alkali or urea. Modification of NH₂ and COOH groups resulted in almost complete loss of the stabilization ability. Modification of histidine and tyrosine fairly well promoted a decrease in this function. Reduced κ-casein stabilized interestingly more α_s-casein than native κ-casein did. Modification of other amino acids had little effect on the stabilization ability. Results of isoelectric focusing indicate that κ-casein was unable to maintain its stabilization function when its isoelectric point in 6M urea moved toward acidic side beyond pH 5. Six components of reduced, κ-casein were clearly separated by isoelectric focusing in 6M urea. We observed that components with isoelectric points at the neutral pH were most susceptible to modification. These components seem to occupy the surface of the κ-casein complex. Chemical modification was shown to result not only in changes in molecular charge, but in changes of molecular size.

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Effect of pH on browning and polyphenol oxidase activity were comparatively investigated using a model system, “ apple enzyme-catechol”. It was observed that the browning as well as the O₂ uptake by the system was equally the highest at pH 6 but not estimated below pH 4, while a difference between the browning and O₂ uptake was found when the system had been supplemented by some substances such as cystine and cysteine. The relative browning of the system at various pH was also estimated for different time. At pH 6 and 5, the optical density reached to the maximum value in a short time and decreased then. On the other hand, the degree of the browning was increased with time at pH 8 and 7 and the highest coloration was established at pH 8 for longer time. Incidentally, absorption spectra of the reaction mixtures were determined. In the presence of sodium sulfite, cysteine and sodium chloride, the browning and O₂ uptake were also determined in the course of reaction. Especially, at pH 4, the browning was accerelated by sodium chloride of low concentration. The absorption spectra of the model system in the presence of sodium chloride were determined and discussed.

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In a continuing study on nutritional values of S-methyl-L-cysteine sulfoxide (methiin), a sulfur containing amino acid extracted from cabbage, authors investigated anticholesterolemic effect of this substance for experimental hypercholesterolemia rat.
Addition of S-methyl-L-cysteine sulfoxide to a cholesterol containing diet markedly prevented the increase of serum cholesterol level of rat, in contrast the control rats produced a hypercholesterolemia by cholesterol containing diet feeding.

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In order to clarify the destructive effects of phenolic compounds in the presence of o-diphenol oxidase on the nutritive value of protein, the effect of increasing the concentration of o-di phenol was studied.
o-Diphenol oxidase preparation used for the preparation of discolored proteins was made from the acetone powder of leafstalks of Fuki (Petasites japonicus Miq.). Discolored proteins were prepared by the reaction of casein with varying amounts of o-diphenol in the presence of o-diphenol oxidase for four hours at pH 6.5 and 35°C. Amounts of o-diphenols added per 50g casein were as follows: isochlorogenic acid-2.78g (Casein-D), 5.54g (Casein-H) ; caffeic acid-0.9g (Casein-G₁), 1.8g (Casein-G₂), 6.08g (Casein-G₃).
The amino acids of casein-H and G₃ were determined by means of ion-exchange chromatography. It was demonstrated that the interaction of casein and o-diphenol in the presence of o-diphenol oxidase caused damage principally to lysine.
The biological value and true digestibility of discolored caseins were determined by modified Mitchell-Carman's balance method with male rats. The following values were obtained for biological value and true digestibility, respectively: casein-D, 79.4 and 94.9; casein-H, 76.1 and 87.6; casein-G₁, 74.5 and 95.6; casein-G₂, 73.4 and 93.7; casein-G₃, 69.1 and 85.3. From the results it is evident that a greater decrease in the biological value and true digestibility of discolored casein was caused by increasing the amount of o-diphenol added in the reaction mixture.

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Young rats weighing about 80g fed a diet low in either tryptophan or methionine showed a decrease in serum protein level. Decreases of gamma globulin were observed in rats fed a low tryptophan diet and that of albumin in rats fed a low methionine diet. But it was not so clear as in the previous report on rats weighing about 45g.
A low level of liver protein was observed in rats fed a low tryptophan diet as same as a previous paper, whereas a tissue atrophy was not so significant in rats fed a low methionine diet as observed previously.

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Following the surveys carried out in 1964 and 1967, with the ratio of thiamine and riboflavin actually determined to various enriched foods to the amounts supposed to be added, further investigations were made in 1968 with 109 items of thiamine enriched and 49 items of riboflavin enriched foods.
The results showed that 43% of the former items and 45% of the latter items fell within 60-119% in ratios of the vitamins found to the amounts tc be enriched.
It was observed among the samples investigated throughout the period of 1964-1968 that some foods including noodles showed large coefficients of variation in ratios of the vitamins found to the amounts supposed to be added.

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