We developed a food exchange list, including confectioneries and alcohol, based on the food exchange list for diabetes, and designed an intake unit record sheet to simplify daily diet. Thirteen healthy women (age: 39.2±7.0 years) filled out a diet diary and intake unit record sheet for seven days. When energy and nutrient intake calculated by the intake unit record sheet were compared with those calculated by the diet diary, the ratios for energy and for macronutrient intake were 0.97-1.09, and correlations were 0.97-0.99. For dietary fiber and for micronutrients, the ratios were 0.79-1.09, and the correlations were 0.70-0.93. The intake unit record sheet was more accurate than the list of food exchange for diabetes for calculating intake of carbohydrate and fat in healthy people who ingested confectioneries and alcohol. Our food exchange list and intake unit record sheet remained accurate when the database was revised to the fifth revised edition of the standard table of food composition in Japan. The developed method is effective for determining the energy and nutrient intake of people in normal health.

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A placebo-controlled study was conducted to examine the effect of Ginkgo biloba extract (ExGb) on blood pressure in 16 elderly volunteers with hypertension. The subjects were assigned to two groups. One group ingested 50mL of a drink containing 40mg ExGb daily for 12 weeks, and the other group ingested the same volume of artificial drink as a placebo for 12 weeks. In the ExGb group, systolic blood pressure, diastolic blood pressure and calculated mean blood pressure decreased significantly. No significant changes in blood pressure were observed in the placebo group. Blood uric acid concentration in the ExGb group had decreased significantly by the end of the study, but no significant change in uric acid was observed in the placebo group. No marked changes were observed in other indexes, including pulse rate, body weight, and serum variables in both groups. However, an increase of GOT and GPT were observed in one volunteer who had taken the ExGb-containing drink.

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Glucosyltrehaloses, such as 6-O-α-glucosyltrehalose, have both anti-dental caries activities and growth-promoting effects on the genus Bifidobacterium, which plays important roles in improving human fecal flora. Here we show the enzymatic formation of glucosyltrehaloses from trehalose as a sole substrate (glucosyl donor and acceptor) using a thermostable α-glucosidase from Bacillus sp. SAM1606. This enzyme has high transglucosylation activity and broad substrate specificity, and can efficiently act on trehalose. Reaction of the enzyme with 1.32M trehalose at 60°C and pH 6.0 yielded a significant amount of tri- and tetrasaccharides, which were found to be 6-O-α-glucosyltrehalose and 6-O-α-isomaltosyltrehalose, respectively, by MS and NMR analyses. We also analyzed the effect of mutations at position 273 of the enzyme on the reactivity and specificity of transglucosylation. All mutant enzymes showed reduced glucosyl transfer activity; in particular, mutants substituted with Lys, Arg, His, Phe, Trp, or Tyr showed virtually no glucosyl transfer activity to trehalose.

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We examined the effects of a 4% erythritol drink (drink 1) and a 4% glucose drink (drink 2) on alterations in concentrations of plasma glucose, blood lactate, and serum insulin, free fatty acids (FFA) and ketone bodies induced by 90min aerobic exercise. We further examined the effects of 2% erythritol/2% fructose drink (drink 3) and 2% erythritol/1.1% fructose/0.8% glucose drink (drink 4) on alterations in these parameters. Intake of drink 2 during exercise tended to increase the concentrations of plasma glucose and serum insulin, but intake of drink 1 did not. Concentrations of serum FFA and ketone bodies gradually increased with both drink 1 and drink 2, but the increases were higher with drink 1. The values immediately after exercise and 30min later were significantly different between the tests of the two drinks. The blood lactate concentration was not raised during exercise in either test and was not different between the two tests. Intake of drink 3 or drink 4 did not affect exercise-induced alterations in the concentrations of plasma glucose and serum insulin. On the other hand, exercise-induced increases in serum FFA and ketone body concentrations were greater in the test of drink 3, which did not include glucose, and the values after exercise were significantly higher in the test of drink 3 than in the test of drink 4. These results suggest that the fatty acid metabolism promoted by aerobic exercise is inhibited by intake of 0.8-4.0% glucose solution during exercise, but not by intake of 4% erythritol solution or 2% erythritol/2% fructose solution.

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Little known about the physiological and industrial applications of Rhodotorula mannan with repeated β-1, 3 and 1, 4 bonds, which is excreted from the cells of yeast and is different from Konjak mannan in its chemical structure. This study was carried out to examine the effects of mannan on serum and liver lipid concentrations in rats fed cholesterol-free and -enriched diets. The serum triacylglycerol concentration was lower in rats fed the diet supplemented with Rhodotorula mannan than in those fed the diet without Rhodotorula mannan, for both cholesterol-free and -enriched diets. For rats fed the cholesterol-enriched diet, the concentration of serum total cholesterol showed a tendency to become lower and the atherogenic index was significantly lower in the rats fed Rhodotorula mannan than in the control rats. The atherogenic index showed a significant interaction between cholesterol and Rhodotorula mannan, indicating that Rhodotorula mannan suppresses an increase in the atherogenic index induced by dietary cholesterol. Addition of Rhodotorula mannan to the cholesterol-enriched diet also lowered the concentration of total liver lipids, and interaction was observed between cholesterol and Rhodotorula mannan. Because ingestion of Rhodotorula mannan did not increase fecal excretion of bile acid or neutral steroids in the cholesterol-fed rats, the effect of Rhodotorula mannan in lowering the serum cholesterol level may be mediated by a mechanism other than enhancement of steroid excretion into the feces.

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The sterol regulatory element (SRE) is commonly found in the promoter region of genes that are down-regulated by an elevation of cellular cholesterol concentration. SRE-Binding proteins (SREBPs) were originally cloned as transcription factors binding to the SRE. Recent studies have shown that SREBPs not only regulate expression of cholesterol-metabolic enzyme genes, but also control expression of sugar and lipid-metabolic enzyme genes that are regulated by nutrients and hormones and are involved in fat metabolism, insulin-resistance, and diabetes mellitus.

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