The injurious action of fusarinic acid on plant growth is proved to be essentially ascribable to the check of plant's respiration, which is caused by the hindrance of formation of catalase and peroxidase etc. in plant tissue. The mechanism of this phenomenon is concluded principally to consist in the chelate-ring formation of fusarinic acid with metal ions, namely, in plant tissue a slight amount of metal ions (Fe, Cu, etc.) is caught with fusarinic acid chelation and then the check of formation of Fe-porphyrin oxidase (catalase, peroxidase, cyto, chrome etc) results.

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1. The enzymatically prepared glucose-l-phophate, formed by the phosphorolysis of starch and usually contaminated with the traces of catalytically active dextrin, was tested, in com-parison with the chemically synthesized one, for its availability in a study of activating ability of carbohydrate as the primer for potato phosphorylase. When the enzymatically prepared glucose-1-phosphate, recrystallized several times from dilute acetone and dilute alcohol successively, was used as the substrate, it was shown that there ere occurred no substaxltlal activation on potato phosphorylase, and that it could be used as the substrate like the synthetic one in a study of priming effect of carbohydrate in the starch-synthesizing reaction of phosphorylase.
2. A study of, the priming effect of glycogen, potato-starch amylose, potato-starch amylopectin, potato starch synthetic starch, and a polysaccharide consisting of 5 glucose units, on potato phosphorylase was carried out, and the color degree of iodine-starch complex formed in the reaction mixture was observed. It was found that the curves obtained, when the color degree was plotted against the time were characteristic for each polysaccharide. This suggests that the nature of the product synthesized from glucose-l-phosphate by the action of potato phosphorylase depends upon the kind and amount of the primer added.

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In view of the interest in the reported⁽¹⁾ herbicidal activity of 2, 4-dichlorophenoxy-acetic acid (I), we prepared it by chlorinating phenol according to the procedure of HOLLEMAN⁽³⁾ and reacting the resulting 2, 4-dichlorophenol⁽³⁾, m.p. 43_??_44°, with monochloroacetic acid in the presence of sodium hydroxide (86% yield), and of calcium hydroxide (80% yield), in the usual manner; the use of calcium hydroxide as a dehydrochlorinating and condensing agent in this reaction proved of industrial importance.
Further, the following metallic salts were prepared and, after recrystallization`from water, their solubilities in water were approximately determined at 20°, represented as g. (anhydrous salt)/100g. of solution: C₈H₅Cl₂O₃Na•H₂O, 5.2; C₈H₅Cl₂O₃K•H₂O, 4.9; C₈H₅Cl₂O₃•NH₄, 3.8; (C₈H₅Cl₂O₃)₂Mg•51/2 H₂O, 1.9; (C₈H₅Cl₂O₃)₂Ca•3H₂O, 0.53; (C₈H₅Cl₂O₃)₂Ba•12/3H₂O, 0.38; (C₈H₅Cl₂O₃)₂Mn, 0.47; (C₈H₅Cl₂O₃)₂Zn, 0.73; (C₈H₅Cl₂O)Cu•41/2H₂O, 0.07.
Furthermore, for characterization, the following derivatives were prepared: amide C₈H₅Cl₂ NO₂, m. p. 154.5_??_155.5° (literature⁽⁶⁾: 152°); anilide C₁₄H₁₁Cl₂NO₂, m. p. 110_??_111°; phenacyl ester C₆H₁₂Cl₂O₄, m. p. 87_??_88°. The last compound seems to be a new one.
The 2, 4-positions of the two chlorine atoms in 2, 4-dichiorophenol were confirmed, by nitrating it to yield known 4, 6-dichloro-2-nitrophenol, m. p. 122_??_123.5° and tcetylating the latter to give known 4, 6-dichloro-2-nitrophenyl acetate, m. p. 77_??_77.7°, which distinctly differs in its melting point from 2, 6-dichloro-4-nitrophenyl acetate (m. p. 150_??_152°), a new derivative we prepared of known 2, 6-dichlorophenol (m. p. 125° (decomp.))⁽⁵⁾. The constitution, of 2, 4-diphenoxy-acetic acid as prepared by us is thus decisively established.

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The kinetics of the formation of solid lignosulphonic acid (the sulphonation in the first stage of sulphite cooking) was carried out using the extracted spruce wood meal (100 mesh) and 12%Na₂SO₃+3%NaHSO₃ solution (pH 6.3) as cooking liquor (liquor ratio 1:10) at 97°, 120° and 137°. From the analysis of the cooking results the sulphonation in the first stage of sulphite cooking are separated into two different sulphonation reactions. If they are treated separately, both of them can be treated strictly as the first order reaction. One reaction (X-reaction) is very fast, and the other (Z-reaction) is slow. The content of the active group (S-group) sulphonated in the first stage of sulphite cooking was 3.8% in lignin, if it were represented as sulphur content. S-group is separated into two groups; X- and Z-groups are sulphonated in X- and Z-reactions, respectively. Their contents are same; 1.90%. The activation energies (temperature coefficients per 10°C. in range 95°_??_135°) of X- and Z-reactions are 16.5 and 35 Cal (1.74 and 3.22), respectively. It is supposed that X-group is a bare active group in the lignin molecule, such as -OH in vanillyl alcohol, and Z-group is masked in some form, such as in weak linkage with carbohydrates.

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A new methed of electrolytic preparation of pure sugar solution which had already been reported by Jun MIZUGUCHI [J. Pzarm. Soc. Japan, 70, 494_??_519 (1950)] was applied to the preparation of xylose from peanut shells.
The saccharified solution obtained by a new saccharification process (0.8 N HClO₄, 97_??_100°, 6 hrs.) was submitted to the electrolysis in the cathode chamber of the diaphragm cell. Then ClO₄, - and furfural ccntained in the saccharified solution were removed through electrolysis, aid HC1O₄ was recovered as anolyte. Thus the saccharified solution was deacidified (pH 4) and refined at the same time by this electrolytic process.
This refined solution was evaporated under reduced pressure to syrup, from which was solidified the crystalline mass giving a mp. of 98_??_104° with the yield of 13%. A more pure xylose was obtained by washing with acetic acid; giving a mp. 140_??_144°, furfural value 102%, and reducing value 98%, with the yield of 3.4%.

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Vitamin B₁-HCl (I), 4-hydroxy-vitamin B₁•HCl (II), 4-methyl-5-β-hydroxyethyl-thiazole•HCl. (III), 2-methyl-4-amino-5-hydroxymethyl-pyrimidine (IV), benzothiazolcmethiodide (V) and N-2-methyl-4-aminopyrimidyl-5)-methyibenzothiazoliumbromide•HBr (VI) were investigated. polarographically. Among these compounds, (I), (II), (V), and (VI) showed the anodic wave respectively, being ascribed to their SH-form which was due to the opening of thiazole ring by the reaction with the alkaline component of medium. Moreover, (V) and (VI) showed the cathodic wave whose height increased with decreasing of the height of anodic wave in the more acidic media. This wave might be ascribed to the reduction of the thiazole ring. In the case of B₁, this cathodic wave was covered with the consecutive current of catalytic hydrogen deposition in buffered solutions. This phenomenon was observed apparently by the method of differential polarography. In the unbuffered acidic medium, the catalytic hydrogen wave was. obtanied in the presence of (II)-(VI) as well as of (I). From these restlts, it was confirmed. that the quaternary thiazoles were changed to their SH-form and were reduced electrolytically to tertiary thiazole.

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Vitamin B₁ and its related quaternary thiazole compounds showed the polarographic catalytic wave in the NH₃-NH₄Cl solution containing cobaltous chloride as well as hexamino cobaltic chloride. In the dilute solutions of vitamin B₁, a double catalytic wave was observed and their two curves of the wave height against the concentration represented the crossing effect like that of protein double-wave. The catalytic wave of vitamin B₁ was suppressed by the reaction with p-chloromercuribenzoate in 0.5 N NH₃-0.1 N NH₄Cl (pH 10.6) containing cobaltous chloride but not in 0.1 N NH₃-0.1 N NH₄Cl (pH 9.6) and in 0.01 N NH₃-0.1 N NH₄Cl (pH 8.5). Bis-(dimethyl-thiocarbamyl)-disulfide produced 1the similar catalytic waves with di- or trivalent cobalt, but dithiodiglycolic acid only with divalent cobalt. From these observations, it was found that the sulfur-containing compounds of lower molecular weight as vitamin B₁ produced a new type of catalytic wave like the protein wave but different from the cystine wave.

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A thiothiazolone derivative of vitamin B₁ (3-[2′-methyl-4′-amino-pyrimidyl-5′]-methyl-4-methyl -5-hydroxyethyl-thiothiazolone) (I) was investigated polarographically. (I) produced neither proper reduction wave nor oxidation wave. However, (I) produced the typical double catalytic wave in NH₃-NH₄Cl solution with di- or trivalent cobalt. The influences of the concentrations of (I), of cobaltous chloride and of NH₃ on the catalytic wave were observed and considered. The catalytic wave of (I) was not suppressed by the reaction of monoiodoacetic acid which was the suppressive agent for the catalytic wave of vitamin B₁. From the observations in pre-sent and preceding papers, a new classification for BRDICKA's catalytic waves was offered.

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Potato phosphorylase was purified by the ammonium sulfate precipitation method, accompanied by heat treatment at 50° for 5min. and dialysis against runniting water. The purest. preparation showed the activity of 2.78 unit/mg. protein (38°), which is approximately in the same order with the purest preparations of the former investigators. The synthesis of starch from glucose-l-phosphate, as catalyzed by this enzyme, proceeds according to zero order reaction rate in itsearly stage until the value, P_inorg/(P_inorg+P_ester), reaches 0.2. The optimum pH of this reaction lies at pH 5.9 (5.5_??_6.3). The dissociation constant between the enzyme and glucoso-l-phosphate (MICHAELIS' constant), as determined by the graphic method, is 1.5×10^-3 M glucose-l-phosphate. The amount of activator polysacchaccharide which gives half maximal velocity is 41.1mg. soluble starch/100ml. The effects of various carbohyd-rate activators on the purifed enzyme were examined to give the results shown in Table 2, from which the behaviors of potato amylopectin, dextran and its hydrolyzates, and amylose produced by the action of isoamylase on glutinous rice starch are discussed. Temperature coefficient of this reaction between 17_??_42° is approximately 2, with the apparent activation energy of 12600 cal./mol. Energy, heat content, free energy, and entropy of activation of the dena-turation of this enzyme by heat (37_??_47°) were determined by using the theory of rate processes of EYRING with results of 49400 cal/mol., 48800 cal. /mol., 24000 cal./mol., and 78 cal./deg. mol., respectively; these results are in support of the protein nature of the enzyme. Purified potato phosphorylase does not require the presence of adenylic acid, cysteine and Mg for full activity. Equilibrium of the reaction, as catalyzed by purified enzyme at pH 6.6_??_6.8, is established when the value, P_i/(P_i+P_e), reaches 0.80_??_0.84; from this value, the equilibrium constant of this reaction is calculated as 4.0_??_5.3. The free energy change of this synthetic reaction is, therefore, approximately -1000 cal./mol. (pH 6.6_??_6.8).

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The effects of various inhibitors on the synthesis of starch from glucoso-1-phosphate, catalyzed by purified potato phosphorylase (18.7 u./ml. and 2.12 u./mg. protein at 37°), were tested and reprensentative results were summarized in Table 1, in which the results by GREEN and STUMPF⁽⁴⁾were also cited for comparison. Heavy metals such as Ag⁺, Cu⁺⁺, Zn⁺⁺, and Hg⁺⁺, had markedly inhibitory effects in very low concentrations, while Pb⁺⁺ was hardly effective in much higher concentrations. Phytohormones, such as α-naphthylacetate and 2, 44 dichlorophenoxyacetate, and adrenalin had more or less inhibitory effects on this enzyme. Insulin, on the contrary, had an activating effect on this enzyme, antagonizing with the inhibitory effect of adrenalin. Arsenate inhibited the phosphorolysis reaction of starch by competing wfth the enzyme with inorganic phosphate. The degree of inhibition by arsenate is nearly directly proportional to the molar ratio of As to P in the reaction mixture (cf. Fig. 1).

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SOKOLOV had already reported, in 1929, the presence of a uterus-contracting constituent in Sclerotinina Lib.
It seemed interesting to take up the study of Scl., which easily forms sclerotium under artificial culture as compared with ergot fungus. In addition, a mutant, Sm, which does not form sclerotium, was unexpectedly derived from original strain, Ss. Biochemical studies were -carried out comparing these two strains. Sm was higher than Ss in protease and β-glucosi-dase activities, but was lower in amylase and maltase activities.

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