We investigated the effects of rice fiber on mineral balance in 5 healthy young Japanese men. The subjects were given 550g of brown rice daily for 2 weeks and 600g of polished rice for the next 2 weeks. Experimental diets including either rice contained 1.2g of protein per kilogram of body weight and adequate minerals. The K, P, and Mg intake was higher in the first 2-week period than in the second 2-week period because of the supply of brown rice.
The weight of the wet and dry feces on the brown-rice diet was twice as much as that on the polished-rice diet. The fecal excretion of K, P, and Mg was greater on the brown-rice diet than on the polished-rice diet. The amounts of K, P, and Mg absorbed were the same on both diets. The apparent absorption rate of K and P on the brown-rice diet was significantly less than that on the polished-rice diet. As the result, balance of absorption and excretion of Na, K, P, Ca, and Mg was similar on both diets. The concentrations of Na, K, Cl, P, Ca, and Mg in plasma were within the normal range on both diets.

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The present study dealt with the effect of intensity of exercise on the transient changes in urinary and dermal nitrogen losses. Six healthy men served as the subjects. The experiment consisted of four consecutive days, pre-control day, control day (C), 60% VO_2max exercise day (60% E) and 80% VO_2max exercise day (80% E). Exercise was loaded for 40min with bicycle ergometer at the intensity of 60% or 80% of VO_2max during exercise period (from 9: 00 to 11: 00).
Urinary nitrogen excretion was depressed, while dermal nitrogen loss was elevated by exercise loading, especially in 80% E. During recovery period (from 11: 00 to 19: 00), higher urinary excretion was observed in 80% E than in C or 60% E, but no significant difference in dermal nitrogen loss was observed in C, 60% E and 80% E. The sum of the urinary nitrogen excretion and the dermal nitrogen loss from 9: 00 to 19: 00, including both exercise and recovery period, was higher in 80% E than in C or 60% E.

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One hundred thirty-six kinds of foodstuffs, which appeared in the dietary records of a group of female college students, were purchased in the market and 101 kinds of dishes were cooked using these foodstuffs.
Zinc content of foodstuffs and dishes was measured by atomic absorption spectrometry after ashing with conc. HNO₃ in the high pressurized teflon vessel. 1) Zinc content of foodstuffs was generally smaller in the present analysis than in the value in literature. 2) Larger zinc content was recognized in the dish with animal foodstuffs than that with plant foodstuffs. 3) Either of two calculated zinc contents in dishes, i. e., calculation based on the analysed value on foodstuffs or that on the recently compiled reference table value, was highly significantly correlated with the analysed content of dishes. Correlation coefficient was 0.955 in the former and 0.922 in the latter. 4) Daily dietary intake of zinc in the menu concerned was mostly less than 10mg with an exception of 17.8mg which was in the day with consumption of oyster.

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Effects of Euglena dry cells on the absorption and metabolism of cholesterol were studied with rats by comparing the Euglena-diet, in which 75% of total protein was replaced with Euglena dry cells, with a casein diet.
No significant difference was found between the Euglena-diet and the casein-diet groups in body weight and relative weight of organs. Excretion of [¹⁴C] -labeled-cholesterol to feces was more in the Euglena-diet group than in the casein-diet group and retention time of cholesterol in digestive tract was shorter in the Euglena-diet group than in the casein-diet group, resulting in low tissue-distribution of cholesterol radioactivity in the Euglena-diet group. No significant difference was found between these two groups in tissue-distribution ratio of absorbed labeled-cholesterol radioactivity.

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Effects of dietary fibers (DFs) on function and morphology of gastrointestinal tract were examined in gastrectomized rats. Animals were gastrectomized and then were given a fiber-free diet er test diets containing 10% wheat bran, 10% solka-floc; cellulose powder or 5% pectin for ten weeks. The following results were obtained: (1) The feeding of pectin prevented the reduction of growth induced by the gastrectomy. (2) The feeding of DFs significantly reduced the apparent digestibility of dietary protein though this reduction did not influence the postoperative growth. (3) The intestinal transit time was significantly shorter in the DF-fed groups than in the control group. (4) The feeding of DFs influenced neither the tissue weight nor the sucrase activities of small intestine. However, the mucosal hyperplasia measured by the increase in DNA content was observed when rats were fed the diet containing solka-floc or pectin. (5) The cecal weight increased only in the pectin-fed group. (6) In the colon, the feeding of DFs caused the elongation of tissues and inhibited the decrease in the muscular weight induced by the operation. Both the solka-floc and the pectin caused the increase in DNA content in the colonic mucosa.

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Alcohol dehydrogenase (ADH) activity and protein content in the liver of SD rats were determined to clarify the differences in liver portion, sex and age. 1) ADH activity in each liver portion was not identical. ADH activity and protein content showed maximum values in the lobus hepatis sinistra lateralis. Both values of ADH activity and protein content in the processus caudatus and processus papillaris were significantly smaller than those in other portions. 2) ADH activity and total ADH activity in the liver of female rats were 2 times and 1.5 times higher than those of male rats, respectively. 3) ADH activity increased lineally from birth to about 12 days and reached the adult level 2 weeks from birth. Total ADH activity increased sigmoidally with postnatal days. The Michaelis constants for ethanol and NAD in rats from 3 to 215 days from birth were constant. The results indicate that the developmental change in ADH activity is attributed to the increase in the specific activity and not to the change in the affinity.

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The effect of the antarctic krill (Euphausia superba) chitin as a dietary fiber on the availability of protein and minerals (Ca, Mg and P) was studied in growing rats fed diets containing 5% krill chitin, lobster (Panulirus gracilis) chitin or cellulose for 10 days. The chitins were prepared by the modified Hackman's method (the treatment with 1 N HCl and 1 N NaOH and the following extraction by acetone) from the frozen blocks of raw krill or the shells of boiled and frozen lobster.
Total nitrogen and ash contents of both the purified chitins were 6.82% and 0.1%, respectively.
The settling volume in water (SV, ml/g) of the examined dietary fibers was 35.0 for krill chitin, 12.0 for lobster chitin and 3.4 for cellulose.
There were no differences in the net protein ratio and retention rate of dietary nitrogen (excluding chitin nitrogen), between krill chitin and the other two dietary fibers.
The most deteriorating effect of the dietary fibers on the mineral balances was observed for krill chitin, followed by lobster chitin. High correlation, |r|=0.707-0.943 (p<0.01), was found between each of the mineral balances (fecal, urinary and total excretion, apparent digestibility, retention and retention rate of the three minerals except urinary P excretion) and the log SV of each dietary fiber. These results show that the effect of krill chitin as a dietary fiber on the bioavailability of minerals can be partly ascribed to its high SV.

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The reaction processes of oxidation and reduction of hemoproteins in steer muscle by nitrite (NO₂-) were kinetically studied. Oxyhemoglobin (HbO₂) was used to compare with muscle hemoproteins in the oxidation process. Oxidation of muscle hemoproteins and HbO₂ by NO₂- proceeded according to the apparent first order kinetics and the sigmoidal mode, respectively. The addition of H₂O₂ or catalase clearly modified the oxidation of HbO₂ but not of muscle hemoprotein. Muscle hemes and HbO₂ differed significantly in the mode of oxidation of hemoprotein by NO₂-. The reduction rate of muscle met-hemes increased with the decrease of [NO₂-] / [heme] at pH 6.0 and 7.4 and at 5°C. The reduction rate of muscle met-hemes was about 20% higher at pH 7.4 than that at pH 6.0. When [NO₂-] / [heme] was 1 at pH 7.4, about 16 days were essential to the complete reduction of musclemet-hemes. The absorption spectrum of muscle hemes after complete reduction was similar to that of HbNO or MbNO.

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Four types of cookies (A, B, C, and D) were made by using each of the four kinds of wheat flour: A, unmodified flour; B, flour with modified starch; C, flour with modified gluten; and D, flour with modified starch and modified gluten. These cookies were made without the addition of fat and their shortness scores were evaluated by sensory tests. High scores were obtained from cookie B and cookie D. Their microstructures were similar to that of a highly shortened cookie made with a sufficient amount of fat. The dough from flour B was harder and that from flour C was softer than that from flour A. The gelatinization of wheat starch delayed as the amount of the added fat increased. The mobility of an oil-soluble free radical used as a spin probe was depressed when wheat starch was gelatinized. From these results it was proposed that the development of shortness in cookie was due to entrapment of alkyl moieties of the fat into the hydrophobic helical coils of starch molecules.

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Amount of zinc supply and consumption (both per day per person values) in Japan was estimated for a period of 1930-1983 using the Food Balance Sheets for the supply and the National Nutrition Surveys for the consumption, Two kinds of zinc content list for foodstuffs: one is the compiled reference from the values, in literature and the second, by our measurements on 136 foodstuffs, were used for calculation of zinc supply and consumption.
Both supply and consumption of zinc were estimated to have dramatically fallen down in 1946 just after the World War II and recovered remarkably until the mid-1950s. The pattern of secular change of zinc consumption resembled more to that of protein than energy consumption.
The estimation of zinc consumption on our actual measurement results revealed very close levels to those reported by the Market-Basket analysis of zinc consumption in Japan.

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Effects of dietary fibers (DF) on digestion and absorption of nutrients were investigated in ileorectostomized rats. After operation, rats were fed a fiber-free diet (FF diet), a FF diet with 10% (W/W) wheat bran, a FF diet with 10% (W/W) solka-floc a FF diet with 5% (W/ W) pectin for 4 weeks and then fed the diets, which casein was removed from those mentioned above, for 10 days. Decreases in the growth and the food intake were observed only in rats fed the FF diet with 5% (W/W) pectin among rats fed the FF diets. Fecal excretion and water excretion into feces increased significantly with the addition of DF to the FF diet. Both apparent digestibilities of dietary protein, lipid and ash and a net digestibility of dietary protein were significantly lower in all rats fed DF than in rats fed the FF diet. Apparent absorptions of dietary Na, K, Ga and Fe also decreased with the DF feeding. Degrees of the decrease in these parameters were dependent on the type of DF.

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Various legumes were examined for their α-amylase inhibitory activities. The α-amylase inhibitory activities were found in 13 cultivars of kidney beans but not in other leguminous seeds. When cranberry beans were soaked in distiiled water for 15hr at room temperature, the inhibitory activity was lessened by 24% and completely lost after boiling treatment for 10min. The same treatment without presoaking reduced the inhibitory activity by 50% of the initial activity in 15min. However, dry heat treatment at 110°C for 30min caused no loss of the activity. The activity level of α-amylase inhibitor in the bean reached a maximum 4 days after germination. A similar change was observed for the trypsin inhibitory activity.

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