The effect of dietary zinc deficiency in rats on serum zinc, hormone, glucose, lipids, and nitrogen compounds contents and enzyme activities was studied.
Serum zinc contents was decreased to less than half of normal level in zinc-deficient rats which were fed a diet containing 1.6 ppm zinc, while it was not changed in zinc-restricted rats which were fed a diet containing 4.9 ppm zinc. However, growth was retarded considerably even in zinc-restricted rats.
Serum alkaline phosphatase, leucine aminopeptidase, and amylase activities were decreased, and glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, and lactate dehydrogenase activities were increased in zinc-deficient rats. The decrease of amylase activities seemed to be related to decreased food intake.
Serum urea-nitrogen, uric-acid, bilirubin, cholesterol, triglyceride, and β-lipoprotein contents were affected by the decrease of zinc intake. Among those, the decrease of urea-nitrogen contents were apparently due to zinc deficiency, but the other effects seemed to be related to decreased food intake. Serum glucose, creatinine, and phospholipid contents were not altered.
Serum triiodothyronine, thyroxine, testosterone, and insulin contents were decreased in zinc-deficient rats, and those effects were by not due to decreased food intake, but due to zinc deficiency.
Total serum protein contents were decreased, but γ-globulin fractions were increased by zinc deficiency. Other fractions of albumin and α- and β-globulins were altered but not in a certain tendency.
Zinc supplementation to zinc-deficient rats improved those symptoms almost perfectly and no lesions of zinc deficiency remained in restored rats with a few exceptions.

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In estimating amount of nutrients intake, various procedures are utilized to know amount of foodstuffs to be consumed or consumed. In this report, three dietary consumption survey methods, i. e. (1) weighing all foodstuffs prior to cooking (weighing method), (2) purchasing the same meal as consumed and separating it into foodstuffs (purchasing method), and (3) asking the housewives who cooked the meal to recall the composition and weight of foodstuffs used (recall method), were tested for 30 meals from 10 housewives living in a village in Oita Prefecture in terms of estimating amount of protein and sodium consumption. The meals concerned were also subjected for nitrogen analysis by using an instrument for elements (C, H and N) analysis (Yanagimoto MT-2) and sodium analysis by atomic absorption spectrometry (Hitachi Zeeman 180-80). From the nitrogen value, crude protein values were calculated by multiplying nitrogen protein conversion factor, 6.25. The new version of Japanese Standard Food Composition Table (Supplements to the 3rd edition) was used for calculation of protein and sodium consumption.
Actually measured values of protein were well correlated with calculation values ; correlation coefficient is 0.933 for the weighing method data, 0.897 for the purchasing method data and 0.715 for the recall method data. However, sodium values actually measured correlated with only purchasing method data with a statistical significance (r=0.478).

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The exudation rates of minerals from dry seaweeds (Konbu, Wakame and Hijiki) into immersion water were determined. Ninety percent of I in Konbu exuded into water during 20 min immersion, but the rate was only 30% for Wakame and Hijiki. There was no significant difference between Konbu, Wakame and Hijiki in exudation rate of minerals other than I : the rates were 60% for Na and K, 50% for P, 20% for Mg and less than 10% for Ca. These results suggest a possibility that the dietary iodine intake of Japanese people would not always be sufficient in their food life.

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We have been proposed the criteria for assessing cariogenic potential of foodstuffs. The criteria derived from four factors, i. e., 1) plaque-forming potential and 2) acid-producing potential as substrate utilized by cariogenic bacteria in the oral cavity, and 3) ingestion time (acting time until swallowing) and 4) clearance time (acting time after swallowing) as the intraoral acting time of substrate.
The purpose of this study was to assess the plaque-forming potential of foods in vitro. The plaque-forming potential was evaluated from the amount of insoluble glucan synthesized in the incubation of foodstuffs with glucosyltransferase of S. mutans 6715 at 37°C for 16 hours. Fourty-two kinds of snack foods, which are commercially available and popular in Japan, were tested. Sugar composition of these foods was also determined. A significant correlation between the amount of insoluble glucan synthesized and the sucrose content was noticed.
These results suggest that plaque-forming potential might be evaluated from the determination of the amount of sucrose in the foods.
However, maltose and maltotriose inhibited insoluble glucan synthesis by 40-50% when (maltose-maltotriose) /sucrose exceeded more than 0.5. This indicates that addition ofmaltose and/or maltotriose to the sweet snacks in a high rate reduced plaque-forming potential of the foods.

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Effects of calcium ion on bovine κ-casein components having different carbohydrate contents were investigated by means of ultraviolet absorption and fluorescence spectra. The blue shift of ultraviolet spectrum of each κ-casein component was observed by the addition of calcium ion and the difference spectrum indicated the absorption maximum at 282 nm and minima at 279 and 286 nm. All κ-casein components gave the same maximum or minima wavelengths in their difference spectra in spite of the difference of carbohydrate content. The extent of blue shift was proportional to the concentration of calcium ion. The effect of calcium ion on the κ-casein component having no carbohydrate was larger than other components which have carbohydrate. It was considered that the natural fluorescence of κ-casein was due to tryptophan residue. The maximum wavelength of fluorescence spectrum of κ-casein component containing most carbohydrates was shorter and the fluorescent intensity was smaller than those of other components. The red shift of the fluorescence spectra by the addition of calcium ion was observed for κ-casein components containing carbohydrates but not for the component having no car-bohydrate. It is considered from these facts that the hydrophobic region of the component containing carbohydrate is exposed to solvent in comparison to that of the component having no sugar, and that calcium ion induces the hydrophobic region to come to the surface of protein. The fluorescence maximum wavelength of unfractionated κ-casein was shorter than those of fractionated κ-casein components. This fact suggests that unfractionated κ-casein forms the stable complex as a result of gathering of κ-casein components having different carbohydrate contents. Furthermore, the following facts have been observed in our laboratory : a) unfractionated κ-casein forms the larger polymer than fractionated κ-casein components, b) the complex of unfractionated κ-casein with other casein components (α_s1- and β-caseins) was larger than corresponding complexes of fractionated κ-casein components with other caseins, c) unfractionated κ-casein is most heat stable. These facts suggest that the heterogeneity of κ-casein is effective on the stability of casein complex and the sugar part of κ-casein takes part in the stability.

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The fatty acid compositions of lipids and the stereospecific distribution of fatty acids in triacylglycerols were determined on the lipids extracted from marketed sheep bones (humerus, femur, scapula and rib) and on the fractionated bone marrow lipids.
Sheep bone marrow lipids were largely composed of neutral lipids, and the predominant fatty acids of lipids were C_{16: 0}, C_{18: 0} and C_{18: 1} acids. The phospholipid fractions contained less C_{16: 0} and C_{18: 1} acids, and more polyunsaturated fatty acids than the neutral lipid fractions of bone marrow lipids.
Of the saturated fatty acids, C_{16: 0} predominated in 1 position, and C_{18: 0} was abundant in 1 and 3 positions ; on the contrary, C_{18: 1} and C_{18: 2} acids were more at 2 position than 1 and 3 positions.
Generally, the fatty acid compostion and triacylglycerol structure of lipid was similar in all four bone marrow samples tested and resembled that of ovine or bovine muscle ipids.
Sheep bone marrow lipid was fractionated by acetone crystallization procedure to yield four fractions of which three were solid and one was liquid fractions. The separated fraction 1, 2, 3 and 4 were composed of 87, 72, 53 and 32% of saturated fatty acids, respectively.
Stereospecific analyses of these fractions revealed that C_{18: 0} was contained more in 1 and 3 positions than 2 position ; on the contrary, that C_{18: 1} and C_{18: 2} were contained more at 2 position than 1 and 3 positions. Although, in case of the fractions with high melting points (fraction 1 and 2) considerable amounts of C_{16: 0} and C_{18: 0} were esterified at 2 positions, contents of those acids at 2 position of fraction 3 and 4 were rather small.

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Seventy-nine young adult females collected their 24-hour urine according to the following time-schedule into separate seven parts : the urine was excreted at 9: 30, and each part of urine was collected at (1) 11: 30, (2) 13: 30, (3) 16: 00, (4) 19: 30, (5) before sleep, (6) after rising in the next morning, and (7) 9: 30, respectively. Sodium chloride, potassium and creatinine concentrations in each urine were measured. The intake of sodium chloride was calculated from the data of food consumption of each subject.
The mean daily excretion of sodium chloride corresponded to the mean figure of its intake, but the figures of the excretion and the intake did not always correspond to each other on the individual basis. Urinary sodium chloride excretion increased in the morning and decreased during sleep. About 21% of sodium chloride to daily total excretion was excreted during 7 hours sleeping period. This suggests a possibility to presume the daily intake of sodium chloride of a group from the excretion in the urine during sleep. Potassium excretion also deminished during sleep. Three peaks of Na/K ratio were observed in a day, corresponding after respective meals. Creatinine excretion decreased slightly during sleep. The decrement was so small that it is possible to estimate the daily sodium chloride excretion from the measurement of NaCl/creatinine ratio of the urine partially collected, especially that during sleep.

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This study aimed to establish a method for quantitative description concerning preschool children's eating behavior.
(1) Two time-sampling techniques were compared with each other : one was carried out by observing the behavior at an interval of 15 seconds (Method A) and the other, at an interval of 1 minute (Method B). From the observation recorded by Method A on 12 children of 3 years old, 210 actions recorded were categorized into 36 subcategories and subsequently into 5 categories such as“0”, rejection of eating; “1”, play not relevant to eating; “2”, play relevant to eating; “3”, actions associated with eating and“4”, eating itself. When the result was expressed as the rate of number of actions belonging to each category to total number of actions observed for individual child as well as the sum of whole subjects, the result by Method B was comparable with that by Method A.
(2) Next, two observation periods (10 days and 20 days) were compared with each other by using Method B, 10-day observations did not necessarily yield the identical result to that by a 20-day observation in terms of the quantitative rate of categorized actions, but a good accordance between the results by two observation periods was obtained for the rank of individual child in the rate of categorized actions to the total.
From these, Method B is judged to be applicable as similar as Method A, but a 20-day observation is rather preferable than a 10-day observation.

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Sugar components of some dry fruits were determined by gas-liquid chromatography. Reducing sugar and sucrose contents were also determined by Bertrand method. All samples were obtained from commercial source. Sugars were extarcted with 99.9% methanol and concentrated methanol solution was used for analysis. Quantitative gas-liquid chromatography was carried out on TMS derivatives of sugars using 3% silicon OV-1 column.
Glucose, fructose and sucrose were the major sugar components. Glucose and fructose were contained nearly at the same ratio except prune and black jujube. In prune, glucose was contained 2.3 times as much as fructose.
Sucrose was found in very small quantities in raisin, prune and banana. In other dry fruits sucrose was contained high percentage. Besides these sugar components sorbitol was found in both apricot and prune, while sorbose was contained in prune only.

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[in Japanese]

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