This study was performed to know the relation between changes of components of Japanese radish and changes of its crisp palatability in the manufacturing processes of pickled one (takuan zuke). Changes of carbohydrates of Japanese radish, especially pectin and activities of some enzymes related to their degradation in the first ten days of the salting were investigated. The results obtained were as follows:
1. Moisture was decreased and ash was increased during this period. But the amounts of crude fiber, crude fat, crude protein, nitrogen-free extract, starch, pectin, soluble total sugar and reducing sugar were hardly changed.
2. Main components of the radish pectin were soluble ones in 0.5% ammonium oxalate and 0.05N hydrochloric acid. It was observed that the former was decreased and the latter was increased during the salting.
3. Polygalacturonase activity was decreased and could not be detected after 3 days of the salting. α-Amylase activity was not changed.
4. Pectin methylesterase activity was markedly increased after 2 days of the salting and quickly decreased after 5 days. Methoxyl contents in radish pectins were decreased and this tendency was notable in 0.05N hydrochloric acid soluble-pectin.
5. By chromatography of 0.05N hydrochloric acid-soluble-pectin on DEAE-cellulose, the retention volume of pectin from the 10 days salted radish needed more 50ml than that from the fresh radish by 50ml.
6. Viscosity of 0.05N hydrochloric acid soluble pectin was markedly increased.
7. Calcium content was increased.
From these results, it was presumed that the increase of viscosity of the radish pectin along with the decrease of methoxyl group content and the increase of the degree of cross-linkage of the pectin resulting from the increase of calcium content were causes of the change of the crispness of the Japanese radish during the salting.

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The tyrosine toxicity that occurs in rats fed a 10% casein diet containing 5% tyrosine can bealleviated by supplement of extra casein or methionine plus threonine.
In this study, the effects of addition of extra casein or methionine and threonine on the ability of tyrosine oxidation were measured using radioactive tyrosine. Weanling rats were fed ad libitum the 10% casein, 10% casein containing 0.66% L-methionine and 0.90% L-threonine, and 30% casein diets, with or without 5% L-tyrosine for 1 or 2 weeks. After a 12 hours fast, animals were ingested a difinite amount of each experimental diet, then injected intraperitoneally with 2μCi of L-tyrosine-U-¹⁴C, and expired CO₂ was collected at hourly intervals for 10 hours. In all groups under investigation the rate of tyrosine oxidation was very rapid and reached a maximum in 1 or 2 hours after injection of radioactive tyrosine, then fell sharply to a much lower level. The catabolic rate of radioactive tyrosine to ¹⁴CO₂ was high in rats fed the diets containing excess tyrosine, but not further increased by the addition of extra casein or methionine plus threonine under the experimental condition.

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The Effect of Thyroid Hormone, Growth Stage and Dietary Protein Level on the Growth and the Liver Arginase in the Mice Kunioki HAYASHI, Yuichiro TOMITA Department of Zootechnical Science, Faculty of Agriculture, Kagoshima University, Kagoshima-shi, Kagoshima The experiments were conducted with intact male mice of the dd strain to investigate the effects of growth stage (23, 33 and 60 days of age) or dietary protein level (5-35%) on the responses of growth and liver arginase to the changes in thyroid function.
To change the thyroid function, L-thyroxine sodium salt (10μg/100g b. w., daily injected) and 2-thiouracil (mixed 0.05% in the diets) were used. Experimental diets were synthetic and they were fed ad libitum during 7 days experimental period. Results are summarized as follows.
1. Though thyroxine promoted the growth in 23 day old mice group, this promoting effect was not observed in the other age groups. Thiouracil suppressed the growth in 33 day old mice group, but not in the other age groups. Furthermore, at low protein (5-15%) diets, it was found that the growth promoting effect of thyroxine was not observed. The relationship between thiouracil effect and dietary protein level was not examined.
2. Liver arginase activity decreased in the thyroxine treated mice groups and increased in the thiouracil treated mice groups at all growth stages. However, when the dietary protein level was ex-tremely low (5%) liver arginase activity increased in the hyroxine treated mice groups.

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The effect of fructose feeding on fructose transport was studied in rat intestinal everted sacs.
Small intestinal everted sacs were made from rats (120-150g) meal-fed a high fructose diet for two weeks.
The time course of the fructose uptake into the everted sacs was observed.
The fructose uptake of rats meal-fed the high fructose diet was approximately 15% greater than that of rats meal-fed the glucose diet. With addition of NaF to the incubation medium, the fructose uptake of rats meal-fed the high fructose diet decreased to approximatelly two-thirds the original amount, but the fructose uptake of rats meal-fed the high glucose diet did not change much from that without NaF in the incubation medium.
Na⁺, K⁺-ATPase activity of the everted sacs showed a remarkable decrease in the presence of NaF.

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In the previous papers, the authors reported on the results of antioxidative effects of metabolites from tryptophan (Trp) to 3-hydroxyanthranilic acid (3-OH-An. A) on the autoxidation of lard. In this paper, the authors investigated the antioxidative activities of metabolic products of several amino acids (proline, phenylalanine, sulfur-containing amino acid and threonine) and metabolites from Trp to serotonine using A.O.M. and DPPH method (1, 1-diphenyl-2-picrilhydrazil).
The results obtained were as follows;
1) 5-oxyindolacetic acid was the most effective and followed by serotonine, 5-hydroxy-L-Trp, Trp in decreasing order in the case of metabolites from Trp to serotonine.
2) In the metabolites of proline, the proline was the most effective and followed by 5-hydroxy-proline, pyruvic and glyoxylic acids in decreasing order.
3) In the metabolites of phenylalanine, the homogentisic acid showed great antioxidant activity on the autoxidation of lard and the next were 2, 5-dihydroxylphenylpyruvic acid and phenylalanine.
4) In the metabolites of sulfur-containing amino acid, the order of antioxidative activities was cysteine>homocysteine>taurine, cystine>cystathionine
5) In the metabolites of threonine, the glycine was the most effective and followed by amino-butyric acid, threonine in decreasing order.
6) When oil was heated for 5hr, antioxidative activity of homocysteine and tocopherol was de-creased, but homogentisic and 3-OH-An. A still kept the activity.

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The spectrophotometric studies of chlorogenic acid were made in several alkaline aqueous solutions, and on the greening phenomenon occurring by the reaction with various nitrogen-containing compounds in such alkaline media.
It was found that chlorogenic acid was autoxidized by the course passing through the yellow sub-stance (366 substance) having λ_max at 366nm in alkaline aqueous solution of nearly pH 9, and that the greening compound was formed from the reaction of the 366 substance with amino compounds such as alanine, phenylalanine, and methylamine.

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To clarify the effect of PCB, DDT and other organochloride compounds on thiamine metabolism, rats were separated into six groups and placed on different admixed diets. Group 1 was fed a normal diet; group 2, a PCB supplemented diet; group 3, a DDT supplemented diet; group 4, a BHC supple-mented diet; group 5, a diphenyl supplemented diet; group 6, a carbon tetrachloride supplemented diet. After 50 days of these dietary regimens all animals were sacrificed and various studies were done on the excised tissues.
In PCB treated rats, thiamine levels in blood, liver and sciatic nerve decreased, transketolase ac-tivity in erythrocytes and liver decreased and TPP effect in erythrocytes and liver increased. In DDT treated rats, thiamine levels in blood, brain and liver decreased, transketolase activity in brain and liver decreased and TPP effect in brain and liver increased. In other groups, no significant changes were observed regarding thiamine metabolism. These findings provide direct evidence that changes occur in thiamine metabolism in PCB and DDT poisoned rats.

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Lipolytic activities of 60 samples of human milk obtained from 21 mothers at 5 to 155 days after parturition were determined. The activity was extensively stimulated by addition of 1.0 to 10.0mg of bile acids such as cholic acid, deoxycholic acid and taurocholic acid to 1.0ml of human milk. In the presence of 5.0μmoles (2.0mg) of cholic acid, 36.1±5.0μmoles of free fatty acids were liberated from 1.0ml of human milk at pH 8.0 after 120 minutes incubation at 37°C; the hydrolysis ratio of the fat was 33.9±7.2%. On the other hand, without cholic acid, the amount of liberated free fatty acids was only 4.3±3.2μmoles and the hydrolysis ratio was 3.9±3.2%. The activity observed in the presence of cholic acid was negatively correlated with the stage of lactation (r=-0.437, p<0.01) and positively with fat (r=0.595, p<0.01) and nitregen (r=0.541, p<0.01) contents of human milk.
In the presence of cholic acid, human milk lipase showed the maximum activity between pH 7.8 and 8.8. It was comparatively active under acid conditions even at pH 4.0 but was almost inactive above pH 9.5. It was completely inactivated by heating at 55°C and 60°C for 10 minutes and 2 minutes, respectively.

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