A method for determining the isoamylase activity is devised. A properly diluted enzyme solution is allowed to act at 20°C on a 1% solution of glutinous-rice starch buffered to pH 6.2. After 24 hours, 0.2cc of then reaction mixture is mixed with 2cc of 0.01 N I₂ solution, and diluted to 25cc. Optical density (E) of the solu-tion at 620mμ is read in a Pulfrich photometer, using a 1-cm cell. The increment of E at 620mμ is proportional to enzyme activity within certain ranges. The amount of enzyme is expressed in the “isoamylase unit”, i.e., an increase of E 0.200 being taken as 10 units.
A pH-activity curve is given for yeast isoamylase, which shows a sharp maximum at pH 6.2.

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The β-glucosidase of apricot seeds was purified to a preparation contain a negligible trace amount of α-amylase.
The crystalline β-amylase hydrolyzed amylose to a limit at 73.4% as maltose, so the existence of the arrest point to the β-amylolysis was confirmed.
The purified β-glucosidase could not supplement the crystalline β-amylase, on the hydrolysis of amylose limit β-dextrin.
Hence it may here be considered that the presence of a β-glucosidase-labile linkage in amylose as described by Peat et al., is not convincible.

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The enzymatic hydrolysis of cycasin with cycad-emulsin, prepared from the seeds of Cycas revoluta, is described. As the complete degradation products we obtained about one mole each of formaldehyde, nitrogen gas, and methanol per mole of cycasin, in addition to glucose, the sugar component. These products are the same as those found in the acid hydrolysis of cycasin which has been reported previously. Therefore, it is concluded that the aglycone of cycasin can not be liberated intact as a single component, but decomposes into those smaller molecules as above even by means of the enzymatic hydrolysis.

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P. oryzae is able to grow by its utilization of DL-valine in the absence of a proper carbon source. The formation of α-keto acid, corresponding to the amino acid mentioned, dimethylpyruvic acid is the first step of utilization. This acid (dimethylpyruvic acid) was identified as its 2, 4-dinitrophenylhydrazone. A comparatively small amount of this keto acid could be recognized even in the culture medium containing both DL-valine and sucrose. This fact appears to indicate that certain parts of DL-valine, when added to a medium containing sucrose sufficient for growth, were utilized not as a nitrogen source but as a carbon source, pesecially in the early stage of incubation.

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From taxonomic study of the strain 2A-327 which produces antibiotics showing an especially inhibitory activity against Piricularia oryzae in vitro and in vivo, it was seemed that no species described in Bergey's Manual could agree with this. So this strain was named Streptomyces griseochro-mogenes Fukunaga. Czapek's medium proved to be most suitable as for active substance production by shaking culture.
The three fraction all showing growth inhibitory activity against various fungi, yeast and phytopathogenic fungi were obtained from the culture filtrate. They are seemed to differ from the known antibiotics shown in previous literature, in regard to ultraviolet absorption, solu-bility, paper chromatogram and antimi-crobial spectrum. Therefore, they are named blasticidin A, B and C.

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α-Spinasterol and α-spinasteryl D-gluco-side were isolated from sugar beet pulp. The α-spinasteryl D-glucoside was hydro-lyzed, and each component was identified with α-spinasterol and D-glucose respec-tively. Infrared data showed that α-spina-sterol was identical with that isolated from spinach. α-Spinasteryl D-glucoside has been found for the first time in natue.

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Addition of ethyl diazoacetate to ethyl α, δ-dimethyl-trans-sorbate gives adducts, and hydrolyses of these esters yield (±)-trans-, (±)-cis-3-(trans-2'-carboxypropenyl)-2, 2-dimethyl-cyclopropane-l-carboxylic acids and α, δ-dimethyl-γ-carboxymethyl-trans-sorbic acid. Their structures and configurations are confirmed and (±)-traps-3-(traps-2'-carboxypropenyl)-2, 2-dimethylcyclopropane-1-carboxylic acid is shown to be the race-mic form of the natural chrysanthemum dicarboxylic acid. Thus the geometrical configuration of the side chain of the chrysanthemum dicarboxylic acid is considered to be trans.

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Catalase has been isolated from toad liver in a crystalline form. Kat.-f. of the crystal is 21600 and its crystalline form is a square thin plate.
A recrystallized crystal shows a single boundary in electrophoretic analysis, and its mobility is -2.8×10^-_??_ cm²/V sec. at pH 7.0.
A cow liver catalase isolated at the same time has a mobility of -3.1×10^-5 cm²/V sec. at pH 7.0.
The activity of crystalline toad liver catalase has its optimum at 15° and this
temperature is in accordance with the optimum of the extracted solution, namely, the optimum temperature is constant even when the enzymes are purified to take crystalline forms.
The same experiments were made on the cow liver catalase and we have found that the optimum temperature of the cow liver catalase was 40° upon measuring both extracted solutions and crystalline enzymes.
These results show that the optimum temperatures of catalase are differ accord-ing to the sources from which they are extracted and that this difference is to be attributed to, the . protein parts of the enzyme molecules.

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We purified the catalases of both the spinach leaves and rice-plant leaves by the n-butanol treatment and isolated them into crystalline forms.
The absorption spectrum of the spinach leaf catalase is identical with that of the animal catalase.
The activity of the spinach leaf catalase has its optimum of 15°, but that of the rice-plant leaf catalase at 35°
These optimum temperatures have resemblance to the circumstances where they grow and are independent of enzyme purity.

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An improved method is described for separating saturated fatty acids by reversed-phase paper chromatography. The 2, 4-dinitrophenylhydrazides prepared from saturated fatty acids from C₂ to C₂₂ are run upward on paper impregnated with tetralin, using 90% methanol-acetic acid-tetralin, 80% ethanol-acetic acid-tetralin, or 90% methanol-tetralin as the moving solvent. The simultaneous separations of all even-carbon acids from C₆ to C₂₂, all odd-carbon acids from C₇ to C₁₉, and also all odd- and even-carbon acids from C₇ to C₁₉ can be successfully performed by means of this paper chromatography. The method is useful for the detection of component saturated fatty acids in natural fats.

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