Two healthy human females were loaded with D-phenylalanine-2′, 3′, 4′, 5′, 6′-²H (D-Phe-d₅) (8 mg/kg body weight) together with essential amino acids and a low-protein diet. Blood samples from these subjects were obtained immediately before, and at 1, 4 and 8 h after loading. D- and L-phenylalanine in the plasma were separated by high-performance liquid chromatography, and the molar ratio of Phe-d₅/Phe-d₀ in the L-isomer fraction was determined by gas chromatography-mass spectrometry with a multiple ion detector. The molar ratios of D-Phe-d₅ and L-Phe-d₅ to naturally occurring Phe-d₀ were calculated. The average minimum values of D-Phe-d₅/L-Phe-d₀ and L-Phe-d₅/L-Phe-d₀ were 0.38 (subject S: 0.16, T: 0.60) and 0.015 (S: 0.014, T: 0.015), respectively, both being obtained 1 h after loading. The average maximum values of D-Phe-d₅/L-Phe-d₀ and L-Phe-d₅/L-Phe-d₀ were 0.78 (S: 0.72, T: 0.84) and 0.043 (S: 0.045, T: 0.040), respectively, both being reached 4 h after loading. Thus, the existence of L-Phe-d₅ in plasma confirmed the conversion of D-phenylalanine to the L-form in the human body.

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According to the Market Basket Method proposed by the Japanese Ministry of Health and welfare, given types of fresh foodstuffs were purchased in October, 1985, at nine locations in Japan, i. e., Sapporo, Sendai, Tokyo, Kofu, Nagano, Osaka, Wakayama, Matsue and Kitakyushu. The foodstuffs collected were classified into six groups and each group was analyzed with reference to 23 kinds of food additives naturally present in foods, i. e., 8 kinds of organic acids, 4 kinds of nucleic acids, orthophosphate, benzoic acid, glycerol monostearate, sodium alginate, sulfur dioxide, nitrate, nitrite, mannitol, sorbitol, glycerol and ammonium hydroxide. By comparing the respective daily intakes from fresh foodstuffs with those from processed foodstuffs, it was classified that in the case of some food additives such as glycerol, acetic acid, benzoic acid and succinic acid, large proportions of each daily intake came from food additives artificially added to processed foodstuffs, but that many other food additives investigated, such as nitrate, sodium 5′-inosianate, sodium alginate, malic acid and lactic acid, were taken from natural sources.

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Hair samples cut close to the scalp were collected from 42 young adult women and the zinc concentrations in consecutive 1.5-cm sections from the proximal to the distal end of the hair were analyzed. Several subjects had remarkably elevated zinc concentrations in comparison with other subjects in proximal sections, irrespective of the fact that artificial hair-waving zinc concentrations increased with increasing distance from the scalp in some subjects. Zinc concentrations in two zinc pyrithione-containing cosmetics for hair washing were very high. From these results it was considered that artificial hair-waving produced only a minimal effect, if any, on zinc concentration in hair, and that variations of zinc concentration in hair from different individuals at different distances from the scalp would have resulted from absorption of zinc from cosmetics.

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In order to clarify the effects of dietary soybean phospholipid (SP) on hematological parameters, the concentrations of various lipids and proteins, and the activities of enzymes in serum and liver, a 20% casein diet containing 10% olive oil (OL) as a control, 2.5% SP+7.5% OL, SP+5%OL, 7.5% SF+2.5% OL, or 5% soybean oil+5% OL was fed to male Sprague-Dawley rats for 4 weeks. Weight gain and food intake in these dietary groups showed no significant differences, except for a slight suppression of weight gain in the 7.5% phospholipid group. Erythrocyte and leucocyte counts were similar among all groups, while platelet counts tended to increase with elevation of dietary phospholipid supplement. The concentrations of total lipid, total cholesterol, triglyceride, phospholipid and alpha-tocopherol in serum of rats from the 5% and 7.5% phospholipid groups were lower than those in the other groups. However, liver total cholesterol concentrations in all the phospholipid groups were significantly lower than those in the other groups. Activities of serum GOT, GPT and LDH tended to be elevated slightly by the phospholipid supplement. Concentrations of total protein, creatinine and A/G ratios in serum showed no significant differences in all groups. It was suggested from these findings that 5% or more dietary soybean phospholipid produced a specific physiological effect which might not be attributable to polyunsaturated fatty acids such as linoleate combining with the phospholipid.

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An anorexigenic substance (FS-T), inhibiting spontaneous food intake in rats, was isolated from feces of conventional rats and mice but not from germ-free animals. The bacterial species producing the substance were studied and the physiological effect was compared in germ-free and obese animals. The results obtained were as follows; (1) Saline diluents of feces from conventional rats were incubated aerobically. Six species of aerobic bacteria were detected, and each bacterium was grown in Eugon broth. The anorexigenic activity from the supernatant fraction was compared, and it was shown that only Proteus mirabilis and Escherichia coli excreted FS-T into the medium. (2) The effect of FS-T on food intake was compared between germ-free and conventional mice after i. p. injection. No significant difference could be detected. (3) Sensitivity against FS-T was compared between Zucker obese (fa/fa) rats and their lean litter mates. The percentage reduction in food intake induced by FS-T (0.7 unit/100 g body weight) was different, being 44. 0% in obese rats and 24. 7% in lean rats, respectively.

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Wet milled corn bran (pericarp) was mechanically refined for use as a new source of dietary fiber. Refined corn bran (RCB) was found to contain 85. 2% of neutral detergent fiber (NDF) as its main component. The effect of RCB on both growth rate and the digestibility of certain nutrients, and the changes in its chemical and morphological properties were examined in rats fed diets containing RCB at 5% or 10% as NDF for 4 weeks. Dietary RCB at either level did not depress the growth of wean ing rats, but showed a tendency to decrease dietary protein efficiency. The dietary addition of RCB at higher levels significantly reduced the food efficiency. In addition, RCB exerted weak inhibitory effects on the intestinal absorption of protein and other components. Apparent digestibility of NDF in RCB was estimated to be 18.5% and 13.8% at lower and higher levels, respectively. Observation of intact and fecal RCBs by scanning electron microscopy indicated that the RCB was made thinner and rough on the inner surface during passage through the digestive tract. The latter finding seems to demonstrate that some noncellulosic substances were removed from the intact RCB in the gut.

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Interlaboratory studies were conducted in order to evaluate and improve the neutral detergent method (ND method) and the enzymatic-gravimetric method. First, aliquots of five cereal samples were analyzed using the ND methods conventionally employed in six laboratories. As a result, Van Soest's ND method was modified to include enzymatic digestion with Termamyl and filtration using celite. Using this modified ND method, aliquots of the same samples were again analyzed and lower coefficients of variation (CV) were obtained than those obtained without modification. An improvement of the enzymatic-gravimetric method proposed by Prosky et al. and adopted by the AOAC was done for pretreatment of the sample, the celite washing procedure and the calculating formula. Using the modified method, six samples were analyzed by four laboratories. The CV was greatly improved in comparison with that obtained by Prosky et al. The dietary fiber contents of five samples were measured by the enzymatic-gravimetric method and the Southgate method. There was almost no difference in the results obtained by the two methods.

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The inhibitory effect of pheophorbide on the mutagenicity of benzo (a) pyrene with or without light irradiation was studied. Without light irradiation, 250 μg pheophorbide reduced the mutagenicity of benzo (a) pyrene to about 90%. This inhibitory effect was the same or stronger than that of hemin. On the other hand, pheophorbide was rendered mutagenic by exposure to light, and the mutagenicity was 40% that of 5 μg benzo (a) pyrene. When 5 μg benzo (a) pyrene coexisted with 250 μg pheophorbide under light irradiation, the mutagenicity of benzo (a) pyrene was apparently reduced to 30% because of the antimutagenic effect of pheophorbide.

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The distribution of enteroglial cells and enteric neurons (enkephalin and PHI) in wholemount preparations of the layers of the guineapig jejunum were studied by the peroxidaseantiperoxidase method using antisera to S-100b protein, enkephalin and PHI. The enteric nerve plexuses were composed of enteroglial cells and enteric neurons. There was a delicate network of enteroglial cells extending through the myenteric plexus and submucous plexus. The network formed by these nervous plexuses supported the somata and processes of the enteric neurons. In the myenteric ganglia, many somata of enkephalin-immunopositive neurons were present. PHI-immunopositive neurons were found in the submucous ganglia.

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The lipid characteristics of commercially available Wiener sausages were found to show distinct differences according to both the meat processing plants from which they originated and their grades (JOKYU, superior and HYOJUN, standard grades) according to the Japanese Agricultural Standard (JAS). The lipid content of JOKYU-grade sausages was significantly higher than that of HYOJUN-grade sausages. This finding was reflected in significantly higher amounts of saturated fatty acid (SFA), monounsaturated fatty acid (MUFA), polyunsaturated fatty acid (PUFA) and cholesterol (CHOL) in JOKYU compared with HYOJUN Wiener sausages. On the other hand, the a-tocopherol (α-TOC) levels and 2-thiobarbituric acid (TBA) value for JOKYU sausages were significantly lower than those of HYOJUN sausages. In pooled data from these two grades of Wiener sausage, significantly positive relationships were observed between lipid and CHOL content and between PUFA>18: 2 (PUFA with three or more double bonds) content and TBA value, whereas not significant relationship was seen between α-TOC level and TBA value.

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