The proteolytic enzymes produced by naturally occurring microorganisms during the bread-making process were investigated. We isolated one Gram-positive and aerobic endospore-forming rod bacterium designated B. subtilis M2-4 producing a proteolytic enzyme from traditional and naturally fermented wheat flour. An analysis of the 16S rRNA sequence of the isolated strain revealed it to be 99% identical to Bacillus subtilis. We purified the proteolytic enzyme to electrophoretic homogeneity from the culture supernatant by column chromatography. The calculated molecular mass of the purified enzyme determined by gel filtration was 33 kDa. The proteolytic enzyme showed optimal activity at 55°Cand pH 11.0, and was stable below 50°C and in the pH range of 5.0-11.0. The N-terminal amino acid sequence of the purified protease from B. subtilis M2-4 was AQSVPYGISQIKAPA, the same as other subtilisins. However, this is the first report of its isolation from traditional fermented wheat flour. The purified protease digested acid casein into fragments with hydrophilic and hydrophobic amino acids at the C-terminal, in particular Arg, Glu, Val and Ile.

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The relationship between the hardness of dried Japanese radish root and the pectin content was investigated. When extracted with boiling water, the amount of pectin extracted from dried Japanese radish root was less than that from raw Japanese radish root. On the other hand, when the pectin was successively extracted with boiling water and a hot oxalate buffer solution (pH 4.3), the dried Japanese radish root was easily softened due to the removal of calcium from the tissue. The amount of pectin extracted from the dried radish root was almost the same as that from raw Japanese radish root. The results of gel-permeation chromatography and DEAE-Toyopearl chromatography showed that the pectin from the dried Japanese radish root had been degraded into low-molecular-weight substances. However, while the dried Japanese radish root did not macerate in a boiling water and acidic solution, it did when boiled in a neutral solution, the result of a β–elimination reaction.

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布を1枚あるいは2枚装着した回転ガラス瓶中の温水から外気への熱移動実験により種々の素材の布に対する熱移動係数を測定した。布2枚を装着したときの総括熱移動抵抗と布1枚のときの総括熱移動抵抗の差から布1枚の熱移動抵抗を決定した。繊維の熱伝導率と体積分率が等しい場合、布の熱移動係数は布厚に反比例する。また、綿や麻は熱伝導率が大きいので、これらの布の熱移動係数は羊毛、絹あるいはポリエステルの布に比べて顕著に大きくなった。布の熱移動係数は、熱移動係数の最大値を与える布中の繊維の配列が布面に垂直になっているモデルと、熱移動係数の最小値を与える繊維の配列が布面に平行になっているモデルによる計算値の加重平均により推算できることを示した。また、文献中のモデルによる布の熱移動係数の推算値と実測値の比較を行った。

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The oil mist or kitchen exhaust diffuses into various parts of a house as well as the kitchen itself, the mist is responsible for the formation of oil stains on the surface of respective rooms, i.e., the surface of the ceiling and walls. With an open type kitchen, a range of the oil mist diffusion tends to expand, and the authors believe that the condition of the living-cum-dining room might be deteriorated as a result. Twelve residences in Niigata City were chosen to clarify the extent of the oil stain accumulation. In the first place, four to five Teflon sample plates (20×40 mm) were installed at four corners of the ceiling of the kitchen and living-cum-dining room. Three months after the installation, a process of removing the plates that had been installed in the corners of the ceiling started: the plates were removed one at a time in an interval of one month in order to measure the color difference ( E ^∗ab reading) by chroma meter. Furthermore, in some of the houses chosen, the sample plates were installed in the other rooms as well. It was confirmed that E ^∗ab reading in all residences had increased in accordance with the passage of time. It was noted that the oil stain had a high tendency to accumulate at points where the ventilation stayed, and that the sagarikabe wall was effective for preventing the diffusion of the oil mist. It is also to be noted that the kitchen layout as well as the cooking performance at respective homes had much to do with the accumulation as well as the condition of the oil stains.

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