The biological function of vitamin A for defense and suppresion of inflammation induced by varied causes has been investigated with respect to consumption of the vitamin A, and decrease in eicosanoid productions. In clinical study, it was observed that elevation of α_1-acid glycoprotein (AGP) and C-reactive protein (CRP), which are the acute phase reactants, closely related with decrease in vitamin A, RBP and prealbumin (PA) in patient with lower respiratory infection and mucocutaneus lymph node syndrome (MCLS). In rats, it was verified that absorption of vitamin A from the gut and its release from the liver were not suppressed by inflammation induced by burn injury and hypodermoclysis with terpene oil, and then, in the in vitro and in vivo studies, the enhanced consumption of vitamin A would be assumed under the condition accompained by inflammation. In additon, vitamin A suppressed the production of leukotrienes in macrophages from rat lungs after the stimulation with an endotoxin. These findings suggest that vitamin A deprevation is susceptible to infection due to increased production of leukotrienes.

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There are many advantages of using microorganisms as practical sources of long chain polyunsaturated fatty acids (PUFAs). After searching a wide variety of microorganisms, fungal mycelia were found to be new and rich sources of C-20 PUFAs of dietary and pharmacologically importance. A soil isolate, Mortierella alpina 1S-4, produced 4.3 g/l (274 mg/g dry mycelia) of arachidonic acid (Ara) on cultivation in a conventional carbohydrate medium. The value accounted for more than 65% of the total fatty acids in the extracted lipids from the mycelia. Eicosapentaenoic acid (EPA) was also produced, when M. alpina was grown at low temperature (i.e., 12℃). This temperature-dependent formation of EPA was found to be due to the activation of the enzyme, which catalyzes desaturation at the n-3 position of Ara, by low temperature. The fungus converted oils containing α-linolenic acid, such as linseed oil and perilla oil, to an oil containing EPA (yield, 1.88 g/l). This conversion was independent of the growth temperature. When grown in the presence of sesame oil, the same fungus produced dihomo-γ-linolenic acid (2.17 g/l) with an accompanying marked decrease in Ara production. This was found to be due to specific inhibition of Δ5 desaturase by sesamin and related lignan compounds preset in the oil. Rat liver microsomal Δ5 desaturase was also specifically inhibited by sesamin. Several unique physiological effects of sesamin to animals are also described.

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A modified microbiological assay (microplate assay) of cyanocobalamin (B_<12>) was studied by using a 96-well microplate. Under anaerobic conditions, the growth response of Lactobacillus leichmannii ATCC 7830 to B_<12> in the microplate was similar to that in the tube. The correlation coefficient between B_<12> values・obtained by the microplate assay and those obtained by the tube assay was 0.997. B_<12> autoclaved in the assay medium was converted to a substance which was different from the on-treated B_<12> by HPLC. In the microplate assay, the products of B_<12> autoclaved in the assay medium and treated by sodium bisulfite were biologically more active than non-treated B_<12> on the growth of L. leichmannii. When the microplate assay was used for B_<12> compounds altered by those treatments, standard B_<12> should be used in the sample procedure.

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We investigated the changes in nicotinamide metabolism and its bioavailability by measuring the urinary excretion of N^1-methylnicotinamide (MNA), N^1-methyl-2-pyridone-5-carboxamide (2-Py), and N^1-methyl-4-pyridone-3-carboxamide (4-Py), and calculating the resulting excretion ratios of (2-Py+4-Py)/MNA and 2-Py/4-Py when healthy men were administered daily 75 mg and 150 mg of nicotinamide as a multivitamin preparation for 44 weeks. During the experimental period, the significant variation such as seasonal change within the same group was not observed. In the ordinary dosage group (75 mg of nicotinamide), the respective urinary excretion of MNA, 2-Py, and 4-Py increased about 4.5, respectively, compared with the basal values. In the double dosage group (150 mg of nicotinamide), the respectively. The urinary excretion of nicotinamide was nearly the limit of detection even when the subjects were administered 150 mg of nicotinamide. The elevated values of the urinary excretion were rapidly returned to the basal values when the administration was ceased. The urinary excretion ratios of (2-Py+4-Py)/MNA and 2-Py/4-Py in the groups of ordinary dosage and double dosage were not observed a difference from the control group during the experimental period. From these results, it was concluded that men can fully metabolize and efficiently utilize the nicotinamide at least up to the intake of 150 mg/day.

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The inactivating effect of iron(II)-ascorbate complex ([Fe(II)-ascorbate]) on various phages was previously reported. This paper describes the inactivating effect of [Fe(II)-ascorbate] on phage T5, a phage less sensitive to [Fe(II)-ascorbate]. The inactivation of phage by [Fe(II)-ascorbate] was irreversible. The bubbling of nitrogen gas through the reaction mixture and the addition to the reaction mixture of reducing agents, Fe^<3+>, chelating agents, or radical scavengers inhibited the inactivation by [Fe(II)-ascorbate]. Addition of Fe^<2+> enhanced the inactivation, while H_2O_2, Cu^+, Cu^<2+>, Mg^<2+>, catalase and superoxide dismutase had little or no effect on the inactivation. These findings suggest the possible involvement of active oxygen in the phage in activation by [Fe(II)-ascorbate].

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