Acetoin is not usually produced from E. coli. However E. coli 32 produced acetoin when glucose, fructose or xylose was added to bouillon medium. There was high carboligase (CGase) activity which condensed the hydroxyethyl-TPP complex with free acetaldehyde. Acetaldehyde was required for acetoin formation, and ¹⁴C acetaldehyde was incorporated into acetoin in a cellfree system of E. coli 32 without acetolactate decarboxylase. The results indicated that the acetoin-biosynthetic pathway of E. coli 32 was the same as that of eucaryote.
The addition of glucose to the culture medium resulted in derepressing CGase and in stimulating the production of pyruvate and acetaldehyde. The affinity of CGase for pyruvate was significantly higher than that of acetolactate synthetase (ALSase) involved in valine biosynthesis, and ALSase was inhibited by acetaldehyde. It was, therefore, suggested that the production of acetoin from pyruvate by E. coli 32 aided in removing excess pyruvate produced by sugar catabolism.

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The roots of Arctium lappa L. were examined for polyacetylenes. (11 E)-1, 11-tridecadien-3, 5, 7, 9-tetrayne. (3 E, 11 E)-1, 3, 11-tridecatrien-5, 7, 9-triyne and (3 E)-3-tridecen-5, 7, 9, 11-tetrayn-1, 2-epoxide were found as C₁₃-polyynes. The presence of (4 E, 6 E, 12 E)-4, 6, 12-tetradecadien-8, 10, 12-triyn-1, 3-diyl diacetate and (4 E, 6 Z, 12 E)-4, 6, 12-tetradecadien-8, 10, 12-triyn-1, 3-diyl diacetate, (4 E, 6 E)-4, 6-tetradecadien-8, 10, 12-triyn-1, 3-diyl diacetate and (4 E, 6 Z)-4, 6-tetra-decadien-8, 10, 12-triyn-1, 3-diyl diacetate was demonstrated by comparison with the observed ¹H-NMR analysis with a microcomputer, unclear usage. Further, (8 Z, 15 Z)-heptadeca-1, 8, 15-trien-11, 13-diyne was obtained as C₁₇-polyyne.

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A modified method for efficient extraction of lipids from miso and for successive determination of ethyl esters, total glycerides and free organic acids was developed. By this method, glycerides and ethyl esters of fatty acids were extracted with diethyl ether after adjusting the pH of the miso cake emulsion to 12.0 with 0.02N sodium hydroxide solution. In the conventional celite method, the miso emulsion is filtered on celite and the residue is extracted with diethyl ether. Ethyl esters of fatty acids were determined by direct GC analysis of the first ether extract from the alkaline miso emulsion using DEGS columns. The amount of total glycerides is shown by subtracting the ethylesters of fatty acids from the value obtained by transesterification with BF₃-methanol of the first ether extract of miso. On the other hand, the aqueous layer separated from the first ether extract was acidified to pH 2.0 and then extracted with diethyl ether continuously for 4 days. The resulting acids in the second extract were methylated with diazomethane to determine the amounts of free fatty acids and various non-volatile organic acids. The yield of the first ether extract obtained by our method was about 2-times higher than that by the celite filtration method. The present procedure provides a rapid and reliable method for fractional determination of miso fatty and organic acids as ethyl ester, glycerides and in free forms.

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