Spherical or oval particles, 1_??_3.5 μ in diameter, were usually found in the fresh feces and the night-soil, 5.2×10⁹/g and 2.6×10⁸/g in density respectively. The particles were isolated in a purified preparation, to be protein particles: the chemical composition was 11.1% of total nitrogen, 9.7% of amino acid nitrogen, 16.0% of crude fat and 3.5% of ash; starch was undetectable; no cellular structure, but the concentrical striation lines were observed under the light microscope. When the particles were removed, the feces decreased in BOD, and were more efficiently processed by the activated sludge. Thirty three strains of actinomycetes isolated from feces and activated sludges by use of a medium containing the protein particles as a carbon source, showed the significant activities of decomposing the particles.

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This paper deals with some observation on the dispersion state of kerosin-in-water emulsions stabilized with soya-lecithin at varied concentration of lecithin in the oil phase. The emulsions were prepared at various concentrations of lecithin ranging from 0.2 to 20% wt./wt. Volume fraction of the disperse phase was 0.5 for all specimens tested.
With increasing concentration of lecithin, the mean diameter of the dispersed globules in the fresh preparations decreased rapidly, then increased gradually through a minimum value at 2% wt./wt. of lecithin, although the size distribution of the globules can be approximated to the log-normal distribution function in all the cases. The higher durability also appeared in the specimen stabilized with 2% wt./wt. lecithin. Oil was separated from the emulsified phase rather slowly in the concentration range lower than 2% wt./wt., on the other hand, in the higher range, separated more rapidly during aging. Addition of salt showed a minor effect to the emulsification of any conditions for the lecithin stabilized systems described above.

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A strain of Basidiomycetes was isolated which was capable of producing an acid protease having a strong milk clotting activity. The fungus was identified and designated as Trametes ostreiformis K-1.
In slant culture of the fungus, there observed an abundant formation of basidium bearing four spores on it. The shape of the spore was in a characteristic form resembling to a sheath of pea.
The fungus produced milk clotting enzyme in a high yield on the media added with several sort of meals containing polysaccharides or skim milk.
The purified enzyme was obtained through ion-exchange chromatography and gel filtration. The molecular weight of the enzyme was estimated as 35, 000. The enzyme coagulated specifically κ-and β-casein.
Gohda type cheese was made with the enzyme preparation obtained from culture filtrate of T. ostreiformis K-1.

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When preserving Lactobacillus bulgaricus B-62, B5b, L. acidophilus IAM1043, or L. casei LC-3, in frozen condition at -30°C for 7 to 85 days in 10% skim milk, 5% sucrose, fresh cream, 0.9% NaCI or 1% gelatine, the percentage of injured cells in the survived population (the rate of the cells which became susceptive to Na-acetate) was relatively small and the acid producing activity was scarcely decreased.
In comparison with this, L. helveticus HN showed considerably high injured rate and 99% of survived cells after preserving in frozen condition for 85 days in sucrose solution became susceptive to 0.25M acetate (pH 5.3), and acid production of these viable cells in skim milk was delayed average about 4 hr compared with intact cells. Inoculating these frozen stored L. helveticus in 10% skim milk, and incubating at 37°C, the rapid recovery was recognized in about 4hr and most of the injured cells were repaired within 7 to 8hr.
L. bulgaricus and L. jugurti (intact cells) were found to be relatively sensitive to acetate compared with other lactobacilli and especially the growth of L. jugurti was almost inhibited under the existence of 0.13M Na-acetate.

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1. Incubation of egg yolk with a commercial fungal enzyme preparation sold as an acid proteinase at pH values around 4.0 resulted in increase in the yield of isopropanol extractable lipids.
2. Also, when centrifuged, the incubation mixture was separated into three layers. The top layer was neutral lipids with a small quantity of free fatty acids. The middle layer was consisted of phospholipids, neutral lipids and small quantities of their hydrolysis products, and the bottom layer, a mixture of amino acids and peptide derived from yolk protein by the proteinase action and contained almost no lipids.
3. The separation of lipid of egg yolk by the enzymic method was found to take place by the combining action of acid proteinase and a small quantity of lipase.

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Two groups-four samples of sterilized concentrated skim milk were prepared in order to examine the effects of storage-temperature and heat-treatment for sterilization on the changes of casein complex during storage. Samples I and II were sterilized at 130°C flashly. The former was stored at 30°C and the latter at 5°C. Sample III was sterilized at 130°C flashly and sample IV at 130_??_135°C for 15 sec. Both the samples were stored at 30°C.
The formation of visible sediment was observed in sample I on the 60 th day of storage, while, in sample II, gelation occurred without formation of visible sediment on the 150 th day of storage. The amount of destabilized casein complex increased at latter stage of storage in sample II than in sample I. In sample Il the amount of soluble casein increased till the 30 th day of storage and was kept constant thereafter, though it increased in sample I also after the 30 th day of storage.
The amount of destabilized casein complex increased at earlier stage of storage in sample IV than in sample III. The increment of soluble casein was larger in sample IV than in sample III till the 30 th day of storage but the relation was reversed thereafter.
At the early stage of storage, the increase of soluble casein seemed to be correlated with the increase of destabilized casein complex, but did not seem to be correlated with the changes of calcium and magnesium in the ultracentrifugal whey.

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1. Mechanism of the deodorization of soybean milk by the conidiospores of Aspergillus oryzae was investigated.
2. Aldehydes in soybean milk were reduced to form the corresponding alcohols by the conidiospores, and the degree of reduction was shown to be roughly proportional to the sensory score.
3. Optimum conditions for the deodorization of soybean milk and/or the reduction of n-hexanal were as follows; Optimum temperature was 37°C, optimum pH was 6_??_9 and maximum activity was observed in the conidiospores of 5_??_9 day's cultivation.
4. Activity was lost when the conidiospores were suspended in nutritional medium for 3 hours at 30°C, and it was partly restored with the elongation of hypha, whereas the ones suspended in distilled water for 3 hours showed higher activity than original, which lasted for about 9 hours and then decreased.
5. Possibility of participation of another mechanisms in deodorization was discussed.

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Effects of carbon sources on fatty acid compositions of Lipomyces sp. No. 33 isolated in our laboratory were studied.
The yeast capable of accumulating a large amount of fats in its cells was cultivated in the three kinds of media, namely those containing glucose, D-xylose and sodium acetate, respectively.
In any fat produced from the three carbon sources, the fatty acid compositions and general properties were essentially similar, although some differences were observed in quantities and the iodine values of the solid and liquid fatty acids obtained from the mixed fatty acids. However, five minor fatty acids were detected only on the gas chromatogram of the mixed fatty acids from the fat produced from sodium acetate. Of these minor components, the component X₅, which seems to be vernolic acid, was obtained in the highest yield (7.4%).

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Control of anthracnose on fresh banana clusters by N-benzoyl-L-leucine was studied. Efficacy was juged from the number of lesions formed on banana rind inoculated with spores of Gloeosporium musarum. Soaking a banana cluster into 1000 ppm N-benzoyl-L-leucine after inoculation was more effective than preliminary treatment of the fungicide.
The inhibitory action of N-benzoyl-L-leucine on the fungus was clearly recognized under a microscope as the inhibition of hyphal elongation.
This information might be useful for conservation of banana during long distance transportation

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The volume-changes produced by the reaction of HCl with β-casein were measured with a Carlsberg-type dilatometer. The experiments were carried out under the tempera-ture between 5 and 30°C at pH range from 5.5 to 7.0. Under these conditions the increased volume-changes were observed under constant temperature in all cases. The magnitude of the volume-changes was dependent on temperature, for the volume-changes were greater at high temperature than that at low temperature while similar amount of proton was bound to casein. This change of volume, which was dependent on temperature, seemed to be related to the physico-chemical properties of β-casein which had a tendency to associate with rising temperature. In oder to clarify this point, 4M urea was used, because, the association of β-casein with the increase of temperature is completely inhibited under this condition. Increasing of H⁺ concentration showed a decrease of volume to a minimum value 80ml per 10⁵ g casein when 9 moles of H⁺ were bound. However, when the amount of H⁺ bound exceeded this point, a steady increase in volume as well as the H⁺ concentration was observed. The volume-change produced by the protonation in urea solution was substantially lower than that in solution containing 0.15M KCI. The evidence suggests a conclusion that the temperature, which affected the changes of volume in casein, was a intricate one, owing to the fact that it was associated with rising temperature.

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