In order to get a clue explaining the change of the absorption spectrum of apple juice due to browning, spectra were determined on a model system of apple enzyme and pyrogallol, catechol or chlorogenic acid. In the case of pyrogallol, 2 shoulders at 275mμ and 370mμ and smaller one at 420mμ were observed at the first stage and then flattened except that at 275mμ. However, the maximum increase of the optical density was observed at 300mμ throughout the reaction. With catechol, distinct peak was formed between 380mμ and 390mμ in a short time, probably dependent to quinone forming, and then diminished. However, the peak of catechol at 275mμ was changed into shoulder. Thus, the change of the optical density having the maxima at 290mμ and 250mμ and the minimum at 275mμ was observed, although the peak at 380mμ had been seen in the beginning of the browning. In the case of chlorogenic acid, the peak was first formed at 400mμ and then flattened. The maximum increase of the optical density was determined at 400mμ which was then moved to 380mμ. Incidentally, in the UV range, 2 peaks of chlorogenic acid at 325mμ and 293mμ were disappeared and the new one was formed at 250mμ which was decreased again. Thus, the highest increase of the optical density was observed at 260mμ and the maximum decrease at 300mμ. By comparing the changes of these spectra, it was suggested that the browning of apple juice, at least, could not be attributed only to chloragenic acid.

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An attempt to simplify the A. O. A. C. method for determination of sugars in honey was made to evaluate the quality of commercial honey. For determination of reducing sugars 3, 6-dinitrophthalic acid color reaction was used, for the amount of sample on charcoal column chromatography was reduced to onefifth comparing of A. O. A. C. method.
Charcoal column chromatography separated honey sugars to following three fractions; 1) H₂O eluate (glucose and fructose), 2) 7%EtOH eluate (disaccharides), 3) 50% EtOH eluate (higher oligosaccharides). On the H₂O eluate, total sugars (color reaction) and glucose (I₂ oxidation method) were determined and fructose content was calculated from glucose and total sugars contents. On the 7% EtOH eluate, maltose was determined by color reaction and sucrose was determined after hydrolysis under condition which maltose was not hydrolysed.
The proposed method was applied to four commercial honeys and beekeeper's honeys and the obtained result was comparable to that of A. O. A. C. method.

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The effects of chlorophyll a, pheophytin and chlorophyll metal derivatives on the photochemical decomposition of L-ascorbic acid (AAH₂) and also the photochemical decomposition of chlorophyll-AAH₂ system with co-existence of potassium ferri-cyanide, p-quinone and β-carotene as fluorescence quenching agents was studied.
1. The photochemical decomposition of AAH₂ was greatly accelerated by the existence of chlorophyll a and pheophytin, and the photodecomposition rate was also promoted with Cu-chlorophyllin-Na and Fe-chlorophyllin-Na, especially, by the former. Cu-chlorophyllin-Na itself oxidized AAH₂.
2. The photodecomposition of chlorophyll-AAH₂ system was protected with the co-existence of K₃Fe (CN)₆, p-quinone and β-carotene. However, the effect of p-quinone seems to be accelerated the photodecomposition of chlorophyll-AAH₂ system in higher concentration.
3. Chloropyll, and pheophytin have comparatively strong fluorescence intensity, whereas Cu-chlorophyllin-Na and Fe-chlorophyllin-Na have week fluorescence intensity. The mutuality relationship was found between the fluorescence intensity of the reaction system and the photochemical decomposition of AAH₂.

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Effect of exercise or fasting on the total carnitine content of liver, myocardiac and skeletal muscles were studied in rats. When one hour-swimming was loaded to rats, the level of total carnitine increased significantly in myocardiac and gastrocnemius muscles. In fatigued animals, which were loaded three times one hour-swimming exercise with half an hour rest between the swimming program, total carnitine content of gastrocnemius muscle increased as those of one hour-swimming animals, but that of myocardiac muscle was lowered significantly. Liver total carnitine content was decreased by one hour-swimming work but was recovered to the control level by the heavier swimming exercise.
In fasted animals total carnitine levels increased in both cardiac and gastrocnemius muscles, especially in the latter, but there found no significant change in liver.

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Contents of β-alanine, anserine, carnosine, RNA and DNA were compared in liver and gastrocne mius muscle of β-aianine-treated rats and control for eight weeks after weaning. Effect of β-alanine administration was found greatest in the first week when the metabolism was supposed to change greatly. It is concluded that the increase of RNA contents during growth is repressed, but no effect on DNA. Also accumulation of β-alanine and effect on formation on anserine and carnosine are the most prominent at this point.

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Effect of various carbohydrate sources in diet on activities of glucose-6-phosphate dehydrogenase [EC 1.1.1.49] (G-6-P DH), NAD-specific xylitol dehydrogenase [EC 1.1.1.9] (XDH), and transaldolase [EC 2.2.1.2] (TA) was studied in rat liver.
1) Sequential changes of these enzymes in the liver of rat fed 70% corn starch or 70% sucrose as carbohydrate source were observed: Within 3 days after feeding corn starch diet. cytoplasmic G-6-P DH activity increased to 220% of the normal, and then the activity began to decrease and returned to normal level on the 7th day after feeding. On the other hand, in rat fed sucrose diet, G-6-P DH was 270% of normal level on the 3rd day, 170% on the 7th day and 120% on the 11th day after feeding. In the both groups of corn starch and sucrose diets, activity of TA reached maximum, 140% of the normal, on the 7th day and returned to normal level on the 11th day, and activity of NAD-specific XDH did not change so much as that of G-6-P DH.
2) Rats weighing 70g were fed on various sources of carbohydrates (glucose, fructose, sorbitol, xylitol, sucrose, corn starch, or potato starch) for 3 weeks, and activity of cytoplasmic G-6-P DH was measured: Glucose diet showed 89% of relative activity on the basis of normal level taken as 100%; fructose, 155%; sorbitol, 180%; xylitol, 93%; sucrose, 119%; corn starch, 82%; and potato starch, 69%. This result shows that either fructose or sorbitol makes remarkable dietary induction of G-6-P DH.
3) Rats were adapted to sugar-alcohol (sorbitol or xylitol) diet by. increasing sugar-alcohol content up to 20% step by step for 3 weeks: NAIJ-specific XDH was induced by xylitol diet, but not by sorbitol diet.

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When freeze dried egg white is autoclaved at 100°C, for 30min. or at 120°C, for 30min., its digestibility by rat remarkably decreases. Changes in DNP-available lysine and in vitro digestibility with several proteases were studied for the autoclaved freeze dried egg white samples. DNP-available lysine in the freeze dried egg white decreased by autoclaving but the decrease of available lysine was not sufficient to explain the severe depression of nutritive value of the freeze dried egg white in the feeding experiment with rats. Maximum digestibilities of the freeze dried egg white by several proteases in vitro was generally observed when the samples were autoclaved at 100°C, for 3 to 5min., and the longer autoclaving sharply depressed the digestibilities. However, the digestibilities of the freeze dried egg white autoclaved at 100°C, for 30min. were not lower than those of the values obtained with unautoclaved sample except for pepsin. Only digestibility by pepsin significantly decreased by autoclaving. It was discussed whether the low digestibility of autoclaved freeze dried egg white in vivo is mainly due to the resistance for pepsin or not.

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One of albumin, tannin, sodium chloride, ferrous chloride, and starch was added to the solution of sodium 5′-guanylate, then phosphorus-32 was added as a tracer, and the mixture was boiled. After centrifugation, amount of residual phosphorus-32 and ribose in the supernatant was determined. Of the above substances added, presence of ferrous chloride alone effected marked decrease of phosphorus-32 in the supernatant, with concurrent decrease of ribose. The rate of decrease was greater in phosphorus than ribose. In the solutions that became turbid or formed a precipitate, such as in those added with protein or starch, residual phosphorus-32 in the supernatant tended to decrease but the decrease of ribose was not so marked.

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The autoxidation of L-ascorbic acid (AA) and erythorbic acid (EA) in alkaline solutions was investigated polarographically.
By standing (or the aeration) in the alkaline solutions of pH 9-13, the first and the second oxidation waves of both AA and EA were observed to disappear, while another oxidation wave and a new reduction wave were found to be produced.
The time-course of the autoxidation differed of AA and EA from each other though slight, and was influenced by pH of the alkaline solutions. These courses were classified into four types as shown in Fig. 3.
For the third oxidation wave the half wave potential (E 1/2) in the pH range studied, varied from +0.04 to -0.14 (vs. S. C. E.), and for the reduction wave, from -0.88 to -1.21 (vs. S. C. E). These half wave potentials of the autoxidation product coincided with those of hydrogen peroxide in the same alkaline solutions. Further, these two waves disappeared by adding platinum metal (or platinum chloride solution) into the electrolyte solutions.
Hydrogen peroxide has been concluded as the autoxidation product of AA or EA which showed the third oxidation wave and the reduction wave in the polarogram in alkaline solutions.

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Although animal protein is practically essential to human beings of all ages from nutritional point of view, and cholesterol, being dissolved in animal fat which generally coexists with animal protein in food, is suspected to be related to atherosclerosis, which will be a cause of other diseases such as myocardial infarction, cerebral thrombosis etc. It seems desirable, therefore, to determine the cholesterol content in various animal foods, since such analysis may be very significant in selecting low cholesterol animal protein and, consequently, in prevention of certain diseases.
In this connection, we propose tentatively “cholesterol crude protein index” or “C. C. P. I. ”, which indicates the milligrams of cholesterol in each 100g crude protein. Among various Japanese foods, 196 samples were analysed and their C. C. P. I. values computed; as shown in the following order from lower to higher C. C. P. I. values:
light or white fish meat, crustacea, dark or blood fish meat, cheese, cephalopoda, fish testicles, fish ovaries, shellfish, egg, whale, chicken, cattle, skin of fish, fish viscera and butter

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The distribution of lipoxidase which oxidizes polyunsaturated fatty acid in various foods of plant origin, especially in soybean and its products was studied. Lipoxidase preparation from soybean showed higher resistance against heating in dry state than that treatment in wet state. When the coasely ground soybean was heated in dry state at 80°C, for ten hours, yet 15% of activity was remained. When the soybean lipoxidase was added to the substrate containing antioxidant such as BHA or FG, little ettect were observed in the first stage (i. e. for about thirty minutes) on both of them, however, their effects gradually began to appear thereafter. It was also shown that the lipoxidase activity was extremely low in various foods other than soybean.

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The plasma cholesterol-lowering effect of cereals was studied in rats fed hypercholesterolemic diets. In the Ist experiment, the effect of several cereals were compared with potato starch diet. The plasma cholesterol and liver lipid were significantly reduced by milled, pressed barley and, to a lesser extent, by wheat and rice compared with potato starch. In the IInd experiment, whole barley and milled barley were compared. In comparison with the potato starch, both whole and milled, pressed barley caused marked decrease of plasma cholesterol and liver lipid. However, there was no significant difference between whole and milled barley. In the IIIrd experiment, the plasma cholesterol-lowering effect of the defatted whole barley and the extracted barley oil were investigated. As shown in Table 6, supplementation with the defatted whole barley caused a significant decrease in the plasma cholesterol, whereas the barley oil was less effective than whole barley. From these results, it appears that somewhat non-fat substance of barley contributes to the plasma cholesterol-lowering effect.

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