We studied vitamin B₁ (VB₁) intake in some farm workers (26 men and women living in H-cho, Fukuoka Prefecture) said to have a comparatively high carbohydrate intake, and asked them to eat VB₁-enriched rice over a long period to examine its effect through determination of thiamine levels and transketolase activity in blood. 1) VB₁ intake, allowing for loss during cooking, was 0.67±0.20mg for males and 0.60±0.21mg for females, the rate of intake relative to the standard requirement being low (72.2±25.7% and 89.5±30.8%, respectively). 2) The level of thiamine was significantly improved from 23.3±5.8ng/ml before feeding to 42.5±7.9ng/ml thereafter. 3) The proportion of increase in the thiamine level after intake of VB₁-enriched rice was 192±70% compared with that beforehand. Examination of the dietary contents of three groups, showing high, moderate and low degrees of increase, revealed significant differences in rice intake, celeals energy ratio, and protein energy ratio. 4) A positive correlation was noted between the level of thiamine and the intakes of protein and Ca, and negative correlations were noted between the serum VB₁ level and alcohol (in terms of ethanol) for males and between the serum VB₁ level and glucide and cereals energy ratios for females. 5) Examination of dietary contents in terms of the proportionate increase in thiamine level confirmed the usefulness of eating VB₁-enriched rice especially in a group with a high rice intake and a low protein energy ratio.

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We measured the intakes of total fatty acids, non-saponifiable lipids and cholesterol by 28 female students for 3 days (84 meals), and the figures were 30.0, 2.3 and 0.26g/day, respectively. One group (51 meals) which took eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids (intake group) showed higher intakes of non-saponifiable lipids and cholesterol than another group (33 meals) which did not take EPA and DHA (non-intake group). There was no difference in the intake of n-6 polyunsaturated fatty acids between the two groups. However, the amounts of n-3 polyunsaturated fatty acids for the intake and non-intake groups were 1.3 and 0.8 g/day, respectively. The amount of α-linoleic acid was about 0.8 g/day in both groups. The sum of EPA and DHA in the intake group was0.4g/day. The ratios of n-6/n-3 in the intake and non-intake groups were 5.0 and 8.4, respectively. The ratios of P/S in the intake and non-intake groups were 0.83 and 0.68, respectively.

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Absorption and oxidation of medium-chain triglyceride (MCT) and long-chain triglyceride (LCT) infused in vivo into intestinal loops (Thiry-Vella loop) were studied. Thiry-Vella loops were formed in rat peritoneum using 20cm of jejunum resected from the same animal, both ends being attached open at the peritoneal wall. Thus each prepared loop was used as an in vivo intestine system free from bile and pancreatic juice. Normal absorbability in each loop was confirmed by infusion of a [¹⁴C] glucose. Three hours' cumulative absorption of [¹⁴C] MCT and [¹⁴C] LCT infused into the loop was assayed. The absorption rate of [¹⁴C] MCT was significantly higher than that of [¹⁴C] LCT, being 70.1±14.4% and 19.7±6.3%, respectively. Three hours' cumulative expired ¹⁴CO₂ was also measured in the same animal model as that for the fat oxidation assay. The ¹⁴CO₂ production from [¹⁴C] MCT was 18.8±6.1% of the infused dose, whereas that from [¹⁴C] LCT was only 1.7±1.1%. These results indicate that enterally administered MCT is a more effective energy source than LCT in the absence of bile and pancreatic juice.

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We studied the effect of barley on blood glucose response in normal and diabetic rats. In the first experiment, when male Sprague-Dawley rats were fed diets containing corn starch, barley, brown rice and wheat bran for 64 days, they were administered streptozotocin (4mg/100g body weight) intraperitoneally and the corresponding diet was continued for 46 days. Glucose tolerance was suppressed in normal and diabetic rats fed the barley diet. The effect of barley was especially marked in the diabetic rats. Fasting blood glucose in diabetic rats fed barley was improved to the normal level after 25 days. Such improvements in insulin secretion and in the metabolism of glucose might play an important role in the beneficial effect of barley on the blood glucose response. A second experiment was performed to ascertain the effect of barley on diabetic rats. Glucose tolerance in diabetic rats fed barley was improved as early as 9 days, and was lower than that of normal rats fed corn starch after 33 days. These results suggest that barley could be a useful therapeutic diet for diabetic patients.

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The effects of ingested oat and barley gums on plasma and liver lipid concentrations were examined in genetically obese and lean Zucker rats. Soluble gum preparations extracted from oat and barley were composed mainly of a nonstarchy glucan. Obese and lean male Zucker rats, aged 6 weeks, were fed a standard diet or diets containing gum preparations corresponding to 2% total dietary fiber for 34 days. Liver hypertrophy, fatty liver and hyperlipidemia were observed in obese rats fed a standard diet, compared with their lean littermates. Both oat and barley gums suppressed liver lipid accumulation and elevation of plasma cholesterol concentration in obese rats, whereas plasma triglyceride concentration in both gum groups was rather higher than that in the standard group. The influence of gums on plasma and liver lipid concentrations in lean rats was less marked than that in obese rats. These results indicate that ingested oat and barley gums ameliorate fatty liver and hypercholesterolemia in obese Zucker rats.

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Purified wheat bran (PWB) was prepared from wheat bran (WB) by washing with water and ethanol. The hemicellulose-A fraction (HC-A) and the hemicellulose-B fraction (HC-B) were extracted from WB with alkaline solution. The hypocholesterolemic effects of WB, PWB, HC-A and HC-B were examined in rats fed on a hypercholesterolemic diet containing 1% cholesterol and 0.25% sodium cholate. PWB, HC-A and HC-B significantly prevented the elevation of serum cholesterol level in comparision with WB. HC-B, which is water-soluble, had a more significant effect than HC-A, which is water-insoluble. No remarkable change in gastrointestinal transit time was observed between WB and PWB. Therefore, there was no relationship between the cholesterolemic effect and gastrointestinal transit time. Scanning electron microscopy and sugar component analysis of WB and PWB residues collected from each gastrointestinal tract indicated that the amount of non-cellulosic polysaccharide (hemicellulose) released from the PWB cell wall was significantly larger than that from the WB cell wall. From these results, it was considered that a soluble substance contributed to the hypocholesterolemic effect.

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Using an indigestible dextrin (PF: 58.2% dietary fiber and PF-C: 91.6% dietary fiber as determined by HPLC) obtained through pyrolysis of potato starch, its effects on cholesterol metabolism in rats were evaluated. The results are summarized as follows: 1) The levels of serum cholesterol and trigIyceride ia rats fed a cholester01-free diet for 5 weeks were significantly decreased from 119±7.6mg/dl and 218±39.0mg/dl to 94.2±6.0mg/dl and 145±20.0mg/dl, respectively, following supplementation of 10% PF-C; 2) When rats on a standard diet were supplied with tap-water admixed with 20% PF and 5-20% PF-C against a control for 5 weeks, serum and liver cholesterol levels were significantly decreased according to the magnitude of the change in dietary fiber content; 3) Total bile acid excretion in feces was significanly increased in both the PF and PF-C groups; 4) The content of total short-chain fatty acids, especially propionic acid, in fecal volume rose significantly in both the PF and PF-C groups; 5) Confirmation of the effect of PF-C on serum and liver cholesterol levels was made by switching the drinking water from ordinary tap-water to the PF-C solution.

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The effects of calcium (Ca) carbonate and bovine bone powder (BBP) as dietary calcium sources on Ca metabolism in plasma and bone of vitamin D-deficient rats were investigated. The rats were fed ad libitum on a diet with a high Ca content (1.2%) adjusted with either Ca carbonate or BBP under vitamin D-deficient or -replete conditions for 28 days. During and after feeding, the concentrations of Ca, phosphorus, 25-hydroxyvitamin D₃ (25-OH-D₃) and alkaline phosphatase activity in plasma were measured. Furthermore, femoral bone length, width, weight, strength, Ca and phosphorus contents and mineral density were determined. Under vitamin D repletion, both BBP and Ca carbonate significantly enhanced Ca metabolism in plasma and bone, and there was no significant difference between the bioavailabilities of both Ca compounds in plasma and bone Ca metabolism. In contrast, under vitamin D deficiency, BBP enhanced plasma and bone Ca metabolism in a similar manner to that observed in vitamin D repletion. On the other hand, Ca carbonate showed weaker effects on plasma and bone Ca metabolism than BBP. These results suggest that BBP could be an effective dietary Ca source.

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Norepinephrine-induced arteriole constriction was found to be inhibited by water extracts of prawn, salmon, flatfish, beef, pork, scallop, sea urchin and other species. On the other hand, water extracts of tomato, spinach, Japanese pepper, and sesame stimulated norepinephrine-induced arteriole constriction. Therefore, experiments were designed to identify the active principle in the extract of prawn. It was found that one of the active principles was AMP. It was postulated that AMP was absorbed by the intestine after converting it to adenosine. Adenosine was also found to inhibit norepinephrineinduced arteriole constriction. Based on these results, the physiological significance of biologically active substances in food was discussed.

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The effects of added oryzanol, BHT, sesamol and thiodipropionic acid on the decomposition of tocopherol (Toc), the coloring and oxidation of oils by heating, and their synergistic effects with ascorbyl stearate (As. S) were investigated. Vegetable oils (olive, soybean and hardened soybean oils) with or without additives were heated in glass tubes (2.7×20cm) at 180°C. The remaining amounts of Toc in the oils were determined by HPLC. Color, and the anisidine and carbonyl values of heated oils were determined by the JOCS official method 2. 3. 1. 1 b-7, 2. 4. 26-81, 2. 4. 22-73, respectively. Addition of oryzanol, BHT, sesamol and As. S had no, or only low preventive effects on the thermal decomposition of Toc in the oils. However, mixtures of oryzanol, BHT or sesamol and As. S showed high preventive effects (especially in olive oil). The synergistic effects of mixtures of oryzanol, BHT or sesamol and As. S on the thermal decomposition of Toc increased as the concentration of As. S became higher. A browning reaction of the oil due to heating was most pronunced in the oils containing sesamol than in oils containing oryzanol, BHT or As. S and mixtures of sesamol and As. S. On thermal decomposition of Toc, coloring or oxidation of oil mixtures with thiodipropionic acid and As. S showed greater preventive effects than mixtures of gallic acid, soya lecithin or catechin and As. S examined in the previous study.

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The autoxidative and thermal oxidative stabilities of oils mixed in various ratios were investigated. Vegetable oils (rape seed, soybean, palm, hardened soybean, cotton seed, safflower, high oleic safflower, sesame seed and olive oils) and their blend oils were oxidized in a beaker (4×5.5cm; oils, 10g) at 60°C, or heated in a glass tube (2.7×20cm; oils, 10g) at 180°C, and then the peroxide, anisidine and carbonyl values were measured. The autoxidative and thermal oxidative stabilities of soybean and rape seed oils were greatly increased by blending with palm oil. On the other hand, the extent of the thermal decomposition of tocopherol (Toc) in oils was increased by increasing the quantity of palm oil. Sesame seed oil and a mixture of soybean and sesame seed oils showed the highest stability against thermal oxidation, and moreover, the addition of sesame seed oil suppressed the thermal decomposition of Toc in oils. The most suitable blend ratios for thermal oxidative stability of oils were found to be as follows: The ratios between rape seed and palm oils, soybean and palm oils, hardened soybean and palm oils, cotton seed and olive oils, safflower and high oleic safflower oils, corn and hardened soybean oils, soybean and sesame seed oils were all 2: 8. The ratio between soybean and cotton seed oils was 6: 4, and that between soybean, rape seed and palm oils was 3: 3: 4.

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A study was carried out to investigate the effect of exercise intensity on urinary nitrogen excretion (UN), dermal nitrogen loss (DN) and nitrogen balance (NB). Three experimental periods were planned: control (C), 60% Vo2max exercise (60%E) and 80%Vo2max exercise (80 %E) periods. On the experimental days in each exercise period, exercise for 30min was conducted with a bicycle ergometer twice a day. UN values were of the order 80%E>C>60% E on average, but showed no signifieant differences. DN values were significantly higher in 60%E and in 80%E compared with that in the C period. No significant difference was found between the 60%E and 80%E periods. The sum of UN and DN was of the order 80%E>60%E>C, with significant differences between the C and 60%E periods. NB was negative in all three periods, but that in the 80%E period was more negative than in the other two periods.

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A study was conducted to estimate the daily intakes of calcium, phosphorus and magnesium, which are related to the absorption of calcium in children. Calcium, phosphorus and magnesium intakes were measured in the diet consumed by four children (3 years old) in Hanazono, SaitamaPrefecture, for two days each in February, April and June 1989. All food eaten by the children was purchased by the mother and stored at -24°C. Each foodstuff was subjected to estimation of calcium, phosphorus and magnesium using inductively coupled plasma spectroscopy (ICPS). The mean daily calcium intake was higher than the Recommended Dietary Allowance in Japan. The ratio of calcium against phosphorus was well balanced (1.4 to 1.7). In contrast, the Ca/Mg ratio was higher than the recommended range, although Mg intake was not low. It appeared that Snacks contributed much more to the intake of calcium, phosphorus and magnesium than usual meals.

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