The inactivation of the enzymes by linoleic acid hydroperoxides (LAHPO) was tested in connection with the toxicity of oxidized fat. At the same time, the inhibition of enzyme activities by linoleic acid was also tested. Ribonuclease (RNase), trypsin, chymotrypsin and pepsin which are considered to be simple proteins and not to be SH-enzymes were chosen as the enzymes. RNase was largely inhibited by LAHPO, but the other enzymes were inhibited by linoleic acid as well as LAHPO. The inhibition of each enzyme occurred at different pH. This fact may show that the inhibition occurs by binding of such hydrophobic compounds to the enzyme, and that the surface exposition of hydrophobic region may depend on the pH. Not only the reaction of some specific amino acid residue in the protein molecules with LAHPO, but also the binding of these hydrophobic compounds must be remembered in the mechanism of inhibition.

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Pepsin was activated by incubating with linoleic acid hydroperoxides (LAHPO) at acidic region except at pH 4.0. Especially, the activation was best in pH 5.0 and 6.0 buffers, and the maximum activity attained was about 2 times of the original. It is still not certain whether LAHPO combined to the protein molecule or hydroperoxide groups reacted with some special amino acid residues in the protein molecule. The reactions were very sensitive to pH change and some conformational change of the protein molecule may be involved.

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Oxidation of 2-cis-α-ionylidene-ethanol (II) with active MnO₂ afforded a mixture of 2-cis and 2-trans-α-ionylideneacetaldehydes (III and IV). Reduction of methyl epoxy-α- and -β-ionylideneacetates (Vb, Xb XXIb and XXIIb) with LiAlH₄ gave the diols (VI, XI, XXIII and XXIV). The Wittig reaction of the hydroxyketones (XIII and XVIII) with carb-ethoxymethylenetriphenylphosphorane, followed by alkaline hydrolysis, yielded 5-(1'-and 2'-hydroxy-2', 6', 6'-trimethyl-l'-cyclohexyl)-3-methylpentadienoic acids (XIVa, XVa, XIXa and XXa). The reaction of α-cyclocitrylideneacetaldehyde (XXVII) and dihydro-a-ionone (XXXIII) with carbethoxymethylenetriphenylphosphorane afforded ethyl 3-demethyl-α-ionyli-deneacetate (XXVIIIb) and ethyl dihydro-α-ionylideneacetates (XXXIVb and XXXVb). Physiological activities of the above synthesized compounds on rice seedlings were examined.

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The ability of accumulating androsta-1, 4-diene-3, 17-dione (ADD) in the digestion of cholesterol by Arthrobacter simplex IAM 1660 was examined with 167 compounds and (i) chelating agents, (ii) Ni²⁺, Co²⁺, Hg²⁺, As³⁺, Sb³⁺, Bi³⁺, Cd²⁺, SeO₃^2-, and AsO₂^- ions, and (iii) redox dyes were found effective for ADD accumulation. Ionic state of the chelating agents was unfovorable for ADD accumulation but inactive ethylaenediamine tetraacetic acid could be turned effective with aid of surface active agents and penicilline. Lipophilic structure of the chelating agents was required probably for its penetration through the cell membrane. The target process of the ADD accumulating agents was supposed as 9α-hydroxylation and their possible mechanism of inhibiting 9α-hydroxylation is discussed.

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Seven weakly acidic compounds were newly detected as flavor components of roast barley by using column and gas-liquid chromatographies. These compounds were characterized and identified by MS, IR, UV and NMR spectroscopies and the mixed melting point test.
These are 5-hydroxymaltol, maltol, 5-methylcyclopent-2-en-2-ol-l-one, phenol, m-cresol, pyrocatechol, resorcinol and an unidentified compound (MW 128). Maltol, 5-methylcyclo-pent-2-en-2-ol-l-one and 5-hydroxymaltol have so-called “sugary flavor, ” and these compounds appear to concern with the sweet fragrant flavor of roast barley together with vanillin previously identified.
Phenol, m-cresol, pyrocatechol and resorcinol which have a strong characteristic odor are supposed to concern with the smoky flavor of roast barley.

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The intrinsic viscosity of ovomucin (B) from the thick white was higher than that of the thin white. The relative area of the fast moving component in the electrophoretic pattern of ovomucin (B) from the thick white was about twice that of the thin white. The hexose, hexosamine and sialic acid contents of ovomucin (B) from the thick white were higher than those of the thin white. The intrinsic viscosity and carbohydrate content of ovomucin from the egg white previously freed from lysozyme were low in comparison with those of ovomucin (B). The carbohydrate contents of crude lysozyme from the thick white were higher than those of the thin white, and crude lysozyme obtained from the thick white contained larger amounts of ovomucin-like material than the thin white. From these results, discussion were made about the relation between the properties of ovomucin (B) and ovomucin-lysozyme interaction.

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Changes in sensitivity to gamma and ultraviolet radiations of germinating spores of Steptomyces cacaoi var. asoensis were investigated. The results obtained are as follows: (1) The period highly sensitive to gamma irradiation was found at about 100 to 110 min of incubation in a germination medium, which was different in the timing from that sensitive to heat. (2) The patterns of changes in sensitivity to gamma and ultraviolet radiations during germination were not identical. (3) The presence of chloramphenicol in the germination medium remarkably abolished changes in radiosensitivity of spores druing the germination treatment. Mitomycin C also inhibited the development of rediation resistance during the late phase of germination. (4) Radioprotective effects of freezing and ethanol as a radical scavenger lead us to the view that indirect0type actions of radiation on spores may operate in increase of radiosensitivity during the early phase of germination. (5) The scheme for phase transitions in sensitivities to gamma and ultraviolet radiations during germination was presented in relation to the macromolecular synthesis and heat resistance. Different patterns of the time course were observed on sensitivities to gamma and ultraviolet radiations and heat.

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A considerable browning was observed especially in cortex tissue and along xylem of potato tubers harvested at Sakai in Osaka Prefecture, after irradiation with 10, 20 and 50 krad doses of cobalt-60 gamma rays. This phenomenon was accompanied by the marked increase in polyphenol content and peroxidase activity, and the transient increase in o-diphenol oxidase activity. Total reducing compounds in the tissue were also increased by gamma irradiation.
The browing phenomenon depended on the storage period from the harvest to gamma irradiation treatment. The browning and the transient increase in o-diphenol oxidase activity were completely suppressed in the case of tubers irradiated 3 months after harvest.
There was no significant change in α-amylase activity in all tubers tested.

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Antioxidant activity of d-α-, dl-β, d-γ- and d-δ-tocopherol was investigated with fatty acid methylester of milk fat from which unsaponifiable matter had been removed. Autoxidation was carried out at 50°C and its degree was indicated by peroxide value. α- or β- Tocopherol was more effective at lower concentrations (0.003 and 0.01%) than at higher concentrations (0.05, 0.1 and 0.5%). The antioxidant activity of γ- and δ-tocopherol was increased with the increase of tocopherol concentration within the range of 0.001 to 0.5%. The order of antioxidant activity of these tocopherols, which was compared in terms of the time to reach 30 meq of peroxide value, varied with the concentration; γ>β>δ>α at 0.001%, α>γ>β>δ at 0.003%, γ>δ>β>α at 0.01%, and δ>γ>β>α at the concentrations more than 0.05%. α-Tocopherol at the concentration of 0.003%, which correponded to the concentration in original milk fat, was more effective than other tocopherols at the same concentration and α-tocopherol at other concentrations. Synergism due to the combination of β-, γ-, or δ-tocopherol with 0.003% of α-tocopherol was not observed.

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Milk fat prepared from the same lot of cream by churning and by solvent-extraction was used as substrate for the studies of antioxidant action of added d-α-, d-γ- and d-δ-toco-pherols. The churned milk fat was more quickly autoxidized than the solvent-extrated milk fat at 60°C. α-Tocopherol added to the churned milk fat acted as pro-oxidant. The antioxidant activity of α-tocopherol added to the solvent-extracted milk fat was higher at 0.01% than at 0.05 and 0.1%. Addition of γ- and δ-tocopherols inhibited autoxidation of both the churned and the solvent-extracted milk fat, and antioxidant activity of γ- and δ-tocopherols was higher in the latter than in the former. It is likely that phospholipid acts as a synergist with tocopherol in the solvent-extracted milk fat.

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Among the syntheses of DNA, RNA and protein in Escherichia coli cells, the DNA synthesis was found to be preferentially inhibited at lower concentrations of showdomycin. At such lower concentrations of this antibiotic, serious decreases in the synthesis of deoxycytidine phosphates and in de novo synthesis of deoxythymidine phosphates were found in parallel with the decrease in the synthesis of DNA, although the syntheses of other pyrimidine nucleotides were not significantly diminished. The salvage synthesis of deoxythymidine phosphates was very resistant to this antibiotic. The inhibitory action of this antibiotic on DNA synthesis could be reversed by the concomitant addition of a thiol compound or a nucleoside. When a nucleoside was added after the completion of the inhibition by showdomycin, the recovery of the DNA synthesis from the inhibition was detected only after the recovery of the syntheses of pyrimidine ribotides, pyrimidine deoxyribotides and RNA have become distinct.

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The flavonoid constituents of the leaves of Viscum album Linnaeus var. coloratum Ohwi (Viscaceae) epihyting to Pyrus communis Linnaeus were examined. Three kinds of new flavonoids named Flavoyadorinin-A (I), C₂₃H₂₄O₁₂, mp 245_??_246°C, Flavoyadorinin-B (II), C₂₃H₂₄O¹¹•3H₂O, mp 203_??_206°C, and Homo-flavoyadorinin-B (III), C₂₈H₃₂O₁₅•3H₂O, mp 208_??_210°C (sint. at 130°C) were isolated form the leaves of this plant.
The structures of the Compound (I), (II), and (III) were showed to be 7, 3'-di-O-methyl-quercetin-3-O-mono-D-glucoside (rhamnazin-3-O-D-glucoside), 7, 3'di-O-methyl-luteolin-4'-O-mono-D-glucoside, and 7, 3'-di-O-methyl-luteolin-4'-O-D-glucoapioside, respectively.

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Effects of various factors including incubation time, water content of airdried cells, concentration and pH of KH₂PO₄-K₂HPO₄ mixture, D-glucose concentration, MgSO₄ concentration, GMP concentration, cell concentration, aeration and various kinds of carbohydrates on the fermentative production of GDP-mannose, GDP and GTP from 5'-GMP by air-dried cells of baker's yeast were investigated. The water content of air-dried cells was the most important factor in the fermentation. When the air-dried cells of baker's yeast (100mg/ml) were incubated with 5'-GMP (20μmoles/ml), D-glucose (800μ-motes/ml), potassium phosphate buffer (360μmoles/ml, pH 7.0), and MgSO₄ (20μmoles/ml), 2-hr incubation gave GDP in 20go yield and GTP in 61.1% yield, GDP-mannose being produced in 45% yield after 8-hr incubation. The phosphorylation of 5'-AMP, 5'-dAMP, 5'-dGMP 5'-CMP and 5'-UMP was also observed in high yields under the same conditions.

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Pigments IIIa and IIIb, the major components of flavones in green tea, were isolated in a pure state and identified as 6, 8-di-C-D-glucopyranosyl apigenin, from results of UV, IR, NMR spectra and other analytical data. They were also interconvertible by boiling with mineral acids. One of them, IIIb, gave an equilibrium mixture, which consisted of IIIb₁, IIIb₂, and IIIb₃, when its aqueous solution was heated for extended periods of time. These pigments were distinguished by their interconvertibility and degradation pattern with acid, from another known 6, 8-di-C-glycosyl apigenin, vicenin-2.

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Insecticidally active sulfur derivatives (VI) of dihydronereistoxin (VIa) were synthesized in one step sequence starting from 2-dimethylamino-1, 3-dichloropropane (III) or 1-dimethylamino-2, 3-dichloropropane (IV) by utilizing intramolecular SN 2 reaction.

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Nereistoxin (I) was synthesized from a variety of thiolester derivatives (II) of dihydronereistoxin (III) in fairly good yields. The reductive and oxidative products of nereistoxin (I) were isolated.

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Three new sesquiterpenoids were isolated from Parabenzoin trilobum Nakai as feeding inhibitors against a polyphagous insect, Spodoptera littoralis Boisd and an oligophagous insect, Trimeresia miranda Butler. Host selection of polyphagous insects is also discussed.

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Shiromodiol-diacetate, shiromool, and shiromodiol-monoacetate are insect feeding inhibitors isolated from Parabenzoin trilobum Nakai. On the bases of chemical and spectral evidence we deduced that these compounds have the structure shown in I, XVIII, and XI, respectively.

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