Two kinds of cell wall mannans were isolated from Sake yeast strain, Kyokai No. 7 by two methods. In the first method, Mannan-7K was extracted by agitating with a vibrator in 25% methanol-2.25% KCl and purified by the Sevag method. This preparation procedure failed to produce a good yield of yeast mannan, but the Mannan-7K isolated by this method appeared to have more native cell wall mannan. In the other method according to Peat, Mannan-7P was extracted by heating in 0.2M citrate buffer solution and was purified by formation of insoluble Fehling copper complex. This method resulted in excellent yields of yeast mannan.
In this paper, the molecular weight and structure of the two cell wall mannan preparations were investigated. The molecular weight was determined by the ultracentrifugation method. The molecular weight of Mannan-7K was approximately 100, 000, but that of Mannan-7P was shown to be half of Mannan-7K.
Significant differences were not present between the structure of Mannan-7K and Mannan-7P, by methylation analysis, periodate oxidation, acetolysis and partial acid hydrolysis.
Results of these structural studies indicated that two cell wall mannan preparations from Sake yeast Kyokai No. 7, belonging to Saccharomyces cerevisiae, had essentially the same structural features as that of baker's yeast mannans established by Ballou and his coworkers. The structure of baker's yeast mannan has a backbone of α-1, 6-linked D-mannopyranose units with side chains of mannose units attached to the backbone by α-1, 2-linkages. However, the structures of Sake yeast mannans differed from that of baker's yeast mannan in having mannotetraose side chains consisting of two α-1, 3- and one α-1, 2-linkag-es.

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In this report, side chains of mannans of various brewer's yeasts belonging to Saccharomyces cerevisiae were compared with those of baker's yeast mannans. The mannans of Sake yeasts (6 strains), wine yeasts (5 strains), beer yeasts (4 strains), Shochu yeasts (2 strains) and spirit yeasts (4 strains) were acetolyzed, and the fragments were separated by thin-layer and paper chromatography. All brewer's yeast mannans gave similar acetolysis finger prints, which were distinguished from those of baker's yeasts (5 strains) by the presence of a pentasaccharide component, in addition to the mono-, bi-, tri- and tetrasaccharide.

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Waste waters discharged from heated potato juice contains a large amount of coagulated protein (decanter waste). The supernatant of heated potato juice (clarifier waste) showed more than 10, 000ppm of COD and contained more than 500ppm of SO₂. Treatment of these two wastes was examined using yeasts. Several yeast strains grew well in both wastes (S0₂ 500ppm) and reduced COD by more than 80%. The favourable 2 yeast strains, Saccharomyces cerevisiae var. ellipsoideus and Hansenula anomala were used to the further experiments. The favourable conditions for growth of the former strain and COD reduction were: pH 5, SO₂ 500_??_1000ppm and temperature 30_??_35°C. Aeration rate and SO₂ concentration affected yeast growth. Continuous treatment of clarifier waste using these 2 yeast strains were examined under conditions of aeration rate 1vvm, temperature 30°C, dilution rate 1/24 hr_-1, pH 4.5 and SO₂ 500ppm. Whereas the waste contained 13, 000_??_17, 000ppm of COD, the supernatant of the waste treated using H. anomala contained about 1000ppm of COD. Continuous treatment of the decanter waste with S. cerevisiae var. ellipsoideus using a fermenter (capacity one m³) was examined from September to November under conditions of: aeration rate 0.07_??_0.2vvm, pH 5, temperature 35°C and dilution rate l/12_??_l/24 hr^-1. The effluent from the fermenter was separated by centrifugation, and the resulting solids were dried with a drum dryer. The mean value of waste COD was 14, 200ppm, but the supernatant of the effluent contained 3480ppm and 1.75% (dry matter) of solid, of which 0.39% seemed to originate from yeast cells. The reducing sugar content in the waste affected COD reduction and the solid yield. The yielded solid contained 63.9% crude protein. From experiments on feeding chickens, the yielded solid had the highest percentage of digestable protein (92.2%) compared with feed products, such as dried brewery yeast and soy bean oil extract residues.

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Anti-yeast substance F 16-2 was isolated from the culture filtrate of Bacillus subtilis 16-2 and purified by column chromatography. F 16-2 was an oligopeptide but had no specific ultraviolet absorption. It was similar to bacilysin from its properties and also inhibited the growth of both Gram positive and negative bacteria. The growth of Saccharomyces sake Kyokai No. 7 was inhibited by F 16-2 in sake mash. Fermentation was suppressed, and the final concentration of alcohol reached 17.2% in sake mash infected by F 16-2 whereas 20.0% in normal sake mash.

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Succinylated and maleylated samples from sesame 13S globulin were prepared to compare their solubilities, ultracentrifugal patterns, electrophoretic patterns, titration curves and gelation properties. Both succinylation and maleylation were found to be effective for solubilizing the sesame 13S globulin in water. Up to 1.0M the succinylated sample differed from the maleylated sample on solubility in NaCl solution. Dissociation of both samples increased as their degrees of modification increased. The molecular weights of the subunits and intermediary subunits of sesame 13S globulin were not altered by modification, their disulfide bonds remaining intact. The modification shifted the isoelectric points of the subunits and the intermediary subunits to approximately pH 4.5. The titration curve of the succinylated sample in pH range 7_??_10 was gentler than that of the original sesame 13S globulin. On the contrary, the titration curve of the maleylated sample showed a steeper slope in pH range 7_??_8. Samples with a succinylation degree of 37% and a maleylation degree of 81% were found to form a gel when each sample was dissolved in water at a protein concentration of 24%, heated to 90°C for 20min and then cooled in an ice bath for 10min.

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Four classes of wax lipids (sterylester, longer alkylester, shorter alkylester and hydrocarbon) were isolated from rice bran, and their chemical characteristics and constituents investigated. The main component fatty acids were linoleic, oleic and palmitic acid for sterylester; behenic, lignoceric and palmitic acid for longer alkylester; and oleic and palmitic acid for shorter alkylester. The representative molecular species were sitosteryl linoleate (linoleoyl sitosterol) and sitosteryl oleate (oleoyl sitosterol) for sterylester; dotriacontanyl behenate (behenoyl dotriacontanol), octacosanyl palmitate (palmitoyl octacosanol) and tetratriacontanyl behenate (behenoyl tetratriacontanol) for longer alkylester; and methyl oleate, methyl palmitate and ethyl oleate for shorter alkylester. Straight-chain alkane and alkene, and branched-chain alkene (squalene) were detected as hydrocarbons. The principal carbon number of alkane was C₂₉ and C₃₁ and that of alkene, C₂₉, C₃₁ and C₃₃.

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