Oxalic acid is commonly found in spinach and in other vegetables and some microorganisms. Aspergillus niger produces large amounts of citric acid, and yields gluconic, fumaric and oxalic acids as by-products. As the expectable intermediates producing oxalic acid, pyruvate, citrate, glyoxylate or oxaloacetate was separately added to the growing mycelia of Aspergillus niger during fermentation, and the amount of oxalate was determined during cultivation. Oxalate was produced in all media tested, and was degraded later and a small amount of formate was present in the media. When oxalate was used as a substrate, it decreased, so that it was probably not an end product. Furthermore, it was confirmed that the cell-free extracts of the mycelia in the growth culture had enzyme activities which produced oxalate from both oxaloacetate and glyoxylate and degraded oxalate to formate. Oxalate seemed to be yielded via both oxaloacetate and elvoxvlate and that formate was an intermediate in the nathwav to oxalate deeradation.

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Color, taste and flavour are the most important factors in alcoholic beverage production. Organic acids are effective components in taste and for buffering of “sake.” The composition of organic acids produced by mutants derived from M. anka Nakazawa et Sato IFO 4478 was determined. The organic acid compositions were very similar to the parent strain (IFO 4478) composition, but the amount of lactic acid was reduced by about a quarter. This decrease in lactic acid content did not effect the quality of the alcoholic beverage.

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Alcohol fermentation of uncooked corn and rice grain at a mash temperature between 20°C and 25°C resulted in less dissolution of nitrogeneous substances and a lower production of lactic acid. But the alcohol yield was not affected by this control. Proteinase is usually contained in commercial glucoamylase preparations. In alcohol fermentation of uncooked rice grain, proteinase-free glucoamylase had a depressive effect on the production of lactic acid and dissolution of nitrogeneous substances, and the rate of alcohol fermentation was significantly reduced, but this enzyme showed no effect on alcohol fermentation of uncooked corn grain.
The lactic acid produced and nitrogeneous substances dissolved in the alcohol fermented beer of corn or rice seemed to lead to formation of acetoin and several volatile acids in the acetic acid fermentation, because the amounts of these substances were roughly in parallel with those of the former substances.

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Cell wall components of industrial yeasts incubated in potassium-sufficient (K-4m_M, Na-2m_M) and deficient (K-0m_M, Na-2m_M) medium were analysed. Contents of glucose, phosphorous and protein in the cell wall of yeasts incubated in potassium-sufficient medium were higher than those of yeasts in potassium-deficient medium. But content of glucosamine increased in cells incubated in potassium-deficient medium. In the same manner, proline content was increased in cells incubated in potassium-deficient medium.

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