The molecular formula of decumbin is C₁₆H₂₄O₄. The four oxygen atoms correspond to two free secondary hydroxyl groups and a lactone moiety. The five rings or double bonds required by the molecular formula are assigned to a strain-free α-β unsaturated lactone ring, the lactone carbonyl, a second unit which absorbs a mole of hydrogen perhaps a cyclopropane ring, and another more stable ring presumably a five or six-membered carbocycle. There is only one C-methyl group by the Kuhn-Roth procedure. Decumbin and a more recently reported compound called brefeldin A are evidently identical.

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The comparative studies were carried out on the effects of heat on the sodium αs-, K- and β-caseinate solutions, when they were heated at temperatures ranging from 100° to 140°C for periods up to sixty minutes. The results obtained are as follows:
1. By heating, non-protein nitrogen was liberated most from K-casein and least from β-casein. The phosphorus in each casein fraction was liberated almost completely by heating at 140°C for sixty minutes.
2. Trypsin, as well as pepsin, digested the unheated αs- and K-caseins better than β-casein. By heating, the digestibility of K-casein by trypsin and of αs- and, β-caseins by pepsin were increased a little.
3. By heating at 120°C for thirty minutes, K-casein lost its ability to stabilize as-casein against calcium ion.
4. The esdimentation constant and relative electrophoretic mobility of αs- and K-caseins decreased by heating, while those of β-casein increased. No newly formed component was observed in heated casein both by sedimentation and electrophoretic analyses. Acknowledgement. This study was supported by the research grant of The Morinaga Hoshikai, to whom the authors wish to express their sincere thanks.

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The formation of glutamic dehydrogenase was stimulated by either γ-glutamic hydrazide or hydrazine. The stimulating effects of analogues on the enzyme formation were partially reduced by L-glutamine, L-ethionine, 8-azaguanine, 2, 4-dinitrophenol, sodium azide and chloramphenicol.

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The condensation of alkyl and alkenyl halides (C₁-C₁₀) with mesityl oxide in liquid ammonia afforded a mixture of α-alkyl or α-alkenyl α-isopropenyl (III) and α-alkyl or α-alkenyl α-isopropyli dene acetone (IV) in good yields. These alkyl mesityl oxides are the useful intermediates of methyl alkyl ketones.

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Alkyl mesityl oxides can be converted to methyl alkyl ketones such as methyl heptanone and hexa-hydropseudoionone by means of the two different methods, i.e., acidic cleavage and ozonolysis followed by alkaline cleavage. Thus, a new synthetic method of methyl ketones (RCH₂COCH₃) from alkyl halides (RX) has been established. The condensation of acetone with alkyl or alkenyl halide in liquid ammonia has been also described.

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1. The effect of fatty acid on the formation of L-glutamic acid and its dependence on the derived chemical structure are summarized in the following Figure.
2. C₈ to C₁₈ acids in free form were effective on the accumulation of L-glutamic acid in the culture medium containing sufficient biotin (20 μg/l), particularly myristic, palmitic and margaric acids exhibited considerable effect.
3. In the form of polyoxyethylene sorbitan or polyethylene glycol ester, the effects of palmitic and stearic acids were enhanced remarkably, and yet the effect of lauric acid wass conversely lessened.
4. Striking dissimilarity in the effect was obesrved between polyethylene glycol derivative with ester linkage and that with ether linkage. Polyoxyethylene ethers of higher alcohols were all ineffective.
5. Glycerol or sorbitan esters of fatty acids, which possess slightly hydrophilic property, had little effect in spite of their ester linkages.

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The effect of penicillin G (k) was first investigated on L-homoserine production by Micrococcus glutamicus 534-Co 147 (a threonine requiring mutant). The addition of 4μ/ml of penicillin, 7 to 9 hours after inoculation, brought about the conversion of L-homoserine to L-glutamic acid production. Similar phenomena were observed in L-lysine and L-valine fermentations. In these cases, a homoserine requiring and a leucine requiring mutant of M. glutamicus were used respectively. A marked conversion from lysine and valine to glutamate accumulation occured by penicillin addition. However, in L-isoleucine fermentation with Brevibacterium ammoniagenes ATCC 6871, no glutamate accumulation took place and isoleucine yields were remarkably decreased.

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Oxidations of epigallocatechin in the presence of catechol or pyrogallol with tea oxidase as well as with an oxidizing reagent and the isolation of the oxidation products, categallin (II) and pyrogallin (III), in crystalline form are described. Their absorption spectra are compared with those of pigment P (I) obtained by the oxidation of epigallocatechin and epicatechin, and their structural relationships are discussed.

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A simplified preparative method of 2'-ribonucleotides has been devised. RNA is chemically hydrolyzed with sodium hydroxide and treated with 3'-nucleotidase of Bacillus subtilis. Then, each of four 2'-nucleotides is easily isolated from concomitant 2'-nucleotides, nucleosides and phosphoric acid, by using ion exchange resins.
Besides, the specificity of the 3'-nucleotidase was proved to be strictly restricted only to 3'-isomers of AMP, GMP, CMP and UMP. Possibility of the use of this enzyme in the determination of 3'-ribonucleotides in mixtures with other isomers was also indicated.
Molar ratio of 2'-to 3'-isomer of each nucleotide in the alkaline hydrolysate of the employed RNA is presented.

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