Adenosine triphosphatase (ATPase) activity of myofibrils isolated from fresh muscle and the muscle stored at 4°C have been measured.
An increase in Mg-activated ATPase activity of myofibrils was caused by lengthened homogenization.
With the progress of aging of muscle, Mg-activated ATPase activity of myofibrils increased remarkably.
When myofibrils from pre-rigor and rigor muscle in 0.16M KCl were treated with 0.6M KCl18mM Tris-maleate solution (pH 7.0), Mg-activated ATPase activity of myofibrils at low ionic strength increased markedly. However, the Mg-activated ATPase activity of the myofibril isolated from the muscle stored at 4°C for 8 days (8-myofibril) increased slightly after the similar treatment.
The dependence of myofibrillar ATPase activity on KCl concentration became greater with the progress of aging of muscle.
These results may show that, as long as ATPase activity and the dependence of ATPase activity on KCl concentration are concerned, 8-myofibril is the most similar to the isolated actomyosin among myofibrils, although actomyosin in muscle may exist in a different form from that in solution. It is suggested that, with the progress of aging, the structural alteration of myofibril occurred and the myofibril became more susceptible to ATP-induced transformation.

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An astringent tea constituent, (-)-epigallocatechin gallate strongly depresses the glossopharyngeal nerve responses of the toad to other green tea constituents and presents a response pattern similar to that of green tea liquor. This substance also exhibits an inhibitory effect on responses to quinine hydrochloride and sucrose, but enhances the response to sodium chloride.

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α-Tocopherol model compound, 2, 2, 5, 7, 8-pentamethyl-6-hydroxychroman was oxidized under oxygen bubbling. Four oxidation products of 2-(γ, γ-dimethylallyl)-3, 5, 6-trimethyl-1, 4-benzoquinone (B), 2, 2, 7, 8-tetramethyl-5-formyl-6-hydroxychroman (C), trimer (D) and tocopherylethane (G) were identified, and spirodimer (E) was tentatively identified by TLC. Two of them, (B) and (C) have not been obtained in the oxidation of α-tocopherol model compound with p-quinone, alkaline ferricyanide and other compounds as oxidizing agent. A scheme of oxidation mechanism of α-tocopherol model compound was also proposed.

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X-Ray diffraction analysis of the α-cyclodextrin complexes with a number of organic guest molecules were carried out. Several different kinds of the X-ray diffraction patterns were obtained. It was found that different guest molecules enclosed within the void of the dextrin cause large changes in the diffraction patterns of the complexes. However, most of the diffraction patterns could be reasonably interpreted in terms of the hexagonal unit cells with minor differences in the unit cell dimensions ranging a=b=27.0_??_27.8Å and c=14.7_??_16.7Å. The crystal structure of the complexes could be accounted for by a closest packing of channel cylinders that are made by coaxial alignments of the dextrin molecules and the cage structure in the crystal, in which the dextrin molecules align non-coaxially, may not be plausible.

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D-Glucose-isomerizing enzyme was purified in a crystalline form with a good yield
from the cells of Bacillus coagulans, strain HN-68, and some phsicochemical properties were investigated.
The purified enzyme was homogeneous on both ultracentrifugal and disc-electrophoretical analyses. The molecular weight of the enzyme was determined to be 175, 000 and 160, 000 from the sedimentation-viscosity method and the gel filtration method, respectively.
The sedimentation coefficient (s°_{20, w}), partial specific volume, E^1%_1cm at 280mμ, and the nitrogen content of the enzyme were determined to be 10.2×10^-13 sec., 0.705 cm³g^-1, 10.6 and 16.2%, respectively. The integral numbers of amino acid residues per molecule cal-culated on the basis of 160, 000 were as follows; Lys₁₂₀, His₄₉, Arg₆₁, Asp₁₈₂, Thr₈₇, Ser₇₀, Glu₁₃₆, Pro₄₄, Gly_l06, Ala₁₄₀, Half-Cys₀, Val₅₃, Met₂₇, Ileu₅₁, Leu₁₃₄, Tyr₅₈, Phe₉₆, Try_l3, and amide-ammonia₈₀.

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Purified enzyme preparation obtained from Bacillus coagulans, strain HN-68 requires Co²⁺ for D-glucose- and D-ribose-isomerizing activities and Mn²⁺ for D-xylose-isomerizing activity. The values of Km for D-glucose, D-xylose and D-ribose were 9×10^-2, 1.1×10^-3, 7.7×10^-2M and of the relative V_max were 0.52, 1.1 and 0.25mg/min at 40°C, respectively. D-Glucose-isomerizing activity was inhibited by D-xylose and D-ribose. However, there was not a difference among three activities of the enzyme with respect to following properties: Activation energy was 14, 600cal per mol. The enzyme was inhibited in a competitive manner by tris (hydroxymethyl)aminomethane, D-xylitol, D-sorbitol and D-mannitol, and the Ki values for these inhibitor were 3×10^-4, 2.5×10^-3, 2.9×10^-2 and 7×10^-2M, respectively. The ratio of three activities did not change by heat- and pH-treatments. Mn²⁺, Co²⁺ and Ni²⁺ protected strongly the enzyme from heat denaturation. The enzyme can isomerize D-glucose, D-xylose and D-ribose to their corresponding ketose, but the kinetic constants and induction studies indicated that D-xylose is the natural substrate for the enzyme.

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A 7S protein isolated from soybean globulins was dissociated into a similar slowsedimenting material (subunit) by the treatment of urea and sodium dodecyl sulfate (SDS).
Sedimentation coefficients of the subunits obtained by treating with 8M urea and 0.25% SDS were 1.35S and 2.00S, and molecular weights were 22, 500 and 34, 000, respectively. These subunits by the both treatments were apparently different in conformation from the results of optical rotatory dispersion, i.e., urea treatment caused the almost complete unfolding of the subunit structure. On the contrary, SDS treatment contributed new partial formation of_??_α-helical conformation for the subunits.
These dissociations were extremely disturbed by the presence of sodium chloride.

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Epoxidation of methyl dehydro-β-ionylideneacetates with perbenzoic acid afforded methyl 1', 2'-epoxy-dehydro-β-ionylideneacetates and then methyl 1', 2'-, 3', 4'-di-epoxy-dehydro-β-ionylideneacetates. 1', 2'-Epoxy-dehydro-β-ionone, obtained byepoxidation of dehydro-β-ionone, was treated with carbethoxymethylenetriphenlphosphorane to give ethyl 1', 2'-epoxy-dehydro-β-ionylideneacetates. Further, sensitive photooxidation of ethyl dehydro-β-ionylidenecrotonate, followed by alkaline hydrolysis, gave 1'-hydroxy-4'-keto-α-ionylidenecrotonic acid. Growth inhibitory activities of the above compounds on rice seedlings were examined.

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From the pyrolysis of L-serine, ten volatile compounds including several pyrazines were identified. Pyrazines were also found from the pyrolysis of L-threonine, but not from that of alanine and considered to be characteristic pyrolysis products of β-hydroxy amino acids. At the same time, diketopiperazines, amines and carbonyl compounds were also found in addition to those described above. Formation mechanism of pyrazine compounds was also discussed.

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In order to convert fumaric acid to l-malic acid continuously by hydrocarbon fermentation, the cultivation of Candida utilis IAM 4215 or Pichia membranaefaciens IAM 4122 which have a high fumarase activity was combined with fumaric acid fermentation by Candida hydrocarbofumarica.
Forty strains of yeasts were tested for their fumarase activities. P. membranaefaciens LAM 4122 and C. utilis JAM 4215 indicated the high activity. After C. hydrocarbofumarica was incubated in n-paraffin medium for 5 days, fumaric acid produced was converted to l-malic acid by the associated culture with P. membranaefaciens IAM 4122 for 4 or 5 days. Yields of l-malic acid based on n-paraffin were 72% and 70% by P. membranaefaciens and C. utilis, respectively.

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