Xylose isomerase, an enzyme isomerizing xylose to xylulose, was produced adaptively when Can-dida utilis, a fodder yeast, was grown in a medium containing xylose. This experiment was carried out in order to isolate and purify the enzyme, and to clarify properties of the enzyme. As a result, it was revealed that the enzyme could be solubilized by plasmolysis, and was purified by dialysis, salting out with ammonium sulfate, precipitating with acetone, and adsorbing to calcium phosphate gel. The enzyme requires some divalent metal ions for its action and among them manganese ion is the most effective. The enzyme is inhibited particularly by ethylenediamine-tetraacetic acid and has somewhat thermotolerant character.

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Phosphodiesterase has been found in the particulate and soluble fractions from young wheat roots. The intracellular distribution of this enzyme was studied by using RNA, oligo DNA and DNPP as the substrates. When oligo DNA was used, 50 to 60 per cent of PPDase activity was found in the soluble fraction and 30 to 40 per cent in the microsomal fraction. Besides magnesium ion, calcium, cobalt, manganese and nickel ions were effective for its activity. The pH optimum of the enzyme was found at 6.0. This PPDase produced 5'-nucleotides from RNA at pH 6.9 on addition of magnesium chloride.

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Attempts were made to form 5'-mononucleotides from non-proliferating cells of various kinds of yeasts. It was found that yeasts were devided into four groups according to their ability to excrete compounds absorbing at 260mμ, the first of which excreted UV-absorbing materials at the acid pH (I), the second at the alkaline pH (II), the third both at the acid and alkaline pHs (III), and the fourth showed weak ability to excrete UV-absorbing materials at both pHs (IV). In general. 3'-mononucleotides were excreted at the acid pH and 5'-mononucleotides at the alkaline pH. Rhodotorula pallida, however, excreted 5'-mononucleotides both at the acid and alkaline pHs.

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A method for the quantitative determination of flavanols in tea leaf and green tea is described. Separated flavanols on two-dimensional chromatogram are revealed by spraying dilute diazosulfanilic acid solution and eluted by hot water. To these eluates is added diazosulfanilic acid buffered with sodium acetate and after sufficient color development the absorbances of them are measured spectrophotometrically.

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The effect of high protein intake on the turnover rate of the proteins as well as the protein content of liver cellular fractions has been studied in young rats. When rats fed diets containing high levels of casein, the protein content was increased in various cellular fractions of liver. The incorporation of intraperitoneally injected methionine-S³⁵ into the proteins of these fractions was in the following decreasing order: microsomal, supernatant, mitochondrial and nuclear fraction. The rate of disappearance of radioactivity in various fractions was not so much different from one another, but those of microsomal and supernatant fractions were slightly greater than those of the other fractions. The turnover rates of proteins in all cellular fractions and whole homogenate gradually elevated as the casein level in diets increasing from 25 to 60%. However, the inhancement occurred to a lesser degree than that in the turnover rate of liver proteins with increase in the casein level from zero to 25% which was reported previously.

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Polyphosphoric acid and ethyl polyphosphate were newly applied as catalyst to the syntheses of O-glycosides, glycosylamines and purine nucleosides in good yields by fusion reaction of fully acetylated sugars with some aglycons. The isolated ones were the acetylated phenyl 0-glycosides of β-D-glucofuranurono-6, 3-lactone in 82% yield, of methyl α, β-D-galactopyranuronate in 83% yield, of β-D-glucopyranose in 76% yield, of α-cellobiose in 25%, yield and of α-L-rhamnopyranose in 55% yield, p-cresyl 2, 3, 4, 6-tetra-0-acetyl-β-D-glucopyranoside in 70% yield, the acetyl derivatives of N-p-tolyl β-, N-phenyl α-, N-2-naphthyl α- and N-m-nitrophenyl α-D-glucopyranosylamines in the yields of 70, 55, 81 and 12%, respectively, N-7-(2', 3', 4', 6'-tetra-O-acetyl-β-D-glucopyranosyl) theophylline in 83% yield, N-7-β-D-glycosyl theophylline of D-glucopyranose, of D-xylopyranose and of D-ribopyra-nose in the yields of 63, 43 and 35%, respectively, and N-9-(2', 3', 4', 6'-tetra-O-acetyl-β-D-glucopyra-nosyl)-6-benzamidopurine in 25% yield. The anomeric configuration of the produced glycosides was discussed in relation to the dissociation constants of aglycons.

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Degradation of gibberellin C afforded methyl 1, 7-dimethyl-2α-hydroxy-8-oxo-7α-gibb-4a(4b)-ene-1, 10-diearboxylate, from which gibberellin C was reconstructed. Reactions of desoxogibberellin C are also described.

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This paper deals with the partial correction of our previous paper¹⁾ and with some new results in regard to ammonolysis of the epoxide ring of 2, 3-anhydroribofuranoside derivatives.
Treatment of methyl 2, 3-anhydro-5-deoxy-α-D-ribofuranoside, prepared from D-xylose, with ammonia gave methyl 2-amino-2, 5-dideoxy-α-D-arabinoside and no methyl 3-amino-3, 5-dideoxy-α-D-xyloside which we reported to obtain previously.
The exclusive attack of the nucleophilic reagent at C-2 is inconsistent with a result of C. D. Anderson et al.⁶⁾ in regard to ammonolysis of methyl 2, 3-anhydro-α-D-ribofuranoside.
In contrast to α-anomer, methyl 2, 3-anhydro-5-deoxy-β-D-ribofuranoside gave mainly methyl 3-amino-3, 5-dideoxy-β-D-xyloside. The difference of ammonolysis products between α- and β-anomer will be due to existence of steric hindrance.

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