β-Glucosidase from an extreme thermophile, Thermus sp. Z-1, has a wide substrate specificity and a strong β-galactosidase activity. ¹H-NMR analysis was performed on the structure of oligosaccharides produced in the presence of the enzyme by a transglycosilation reaction, during hydrolysis of lactose, at a high temperature. Oligosaccharides were prepared from a 0.88 M lactose solution by reacting with β-glucosidase from Thermus sp. Z-1 at the concentration of 1.4 U/ml at 70℃ for 120 min.
　Newly transgalactosylated oligosaccharides containing disaccharides and trisaccharides in the reaction mixture were isolated by gel filtration chromatography (Bio Gel P-2) and preparative paper chromatography (PPC), followed by an analysis with ¹H-NMR.
　In trisaccharides, the major component was Galβ1→3Galβ1→4Glc (3'-GL) and Galβ1→6Galβ1→4Glc (6'-GL) and another oligosaccharides were also determined by ¹H-NMR.
　These results suggested that the β-glucosidase from Thermus sp. Z-1 was characterized, preferably by the transfer of galactosyl residue at the non-reducing end by β1→3 linkage.

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　The effects of excess intake of a fermented milk, specially prepared with Lactobacillus plantarum ONC141, on blood biochemical parameters and condition of defecation were studied in 11 healthy adults (average age 30±9 years). The subjects consumed 600 ml/day for six weeks. Ten healthy adults consumed the same amount of regular whole milk as the control group. Serum total cholesterol levels in the fermented milk group increased significantly in the 4th week of ingestion, however this was only temporary. The milk group showed a similar change. There were no other paticular changes in any of the other blood biochemical parameters in either group. Diarrhea was observed in the fermented milk group as 1.9% of the total defecation by frequency, but at a lower percentage than in the milk group (6.3%). No change was seen in either group in defecation frequency, fecal quantity and fecal hardness. There was a tendency of improvement in feeling of defecation in the fermented milk group. No paticular subjective symptoms were observed during fermented milk ingestion. These results suggest that excess intake of the specially prepared fermented milk may not cause any problematic adverse reactions in healthy people.

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　Practically pure α_s1-casein was separated from bovine skim milk by the precipitation procedure in 50% ethanol and urea solutions. It was hydrolysed by cathepsin D at 37℃ in 0.1 M sodium phosphate buffer (pH 6.0). A number of degradation products were observed by urea-polyacrylamide gel electrophoresis (PAGE) after the action of cathepsin D on α_s1-casein but these components as well as undegraded α_s1-casein were mostly precipitated by the addition of 2% (W/V) trichloroacetic acid (TCA). The addition of urea to the precipitation system partly released degradation products into the supernatant. In a precipitation system, 2% TCA-3.3 M urea, inclusion of ethylenediamine-tetraacetic acid (EDTA) up to 40 mM somewhat promoted precipitate formation. By adding Triton X-100 (0.1%) to the precipitation system, a considerable part of components released into the supernatant. This increase in solubility was further promoted by the addition of both Triton X-100 and EDTA. These facts suggest that hydrophobic interactions between peptides including undegraded protein must be taken into account in performing fractionation of enzymatic degradation products of α_s1-casein.

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