• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.136-141
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• 1988

Susceptibility of a thermophilic strain (D-71) of Saccharomyces cerevisiae and an osmotolerant strain (SR-S) of Zygosaccharomyces rouxii to Zymolyase-20T were studied in various renditions. Content of glucan and mannan in cell wall of Saocharomyces cerevisiae D-71 were 14.5% and 14.8%, and Zygosaccharomyces rouxii SR-S were 24.0% and 19.0%, respectively. Susceptibility of Saccharomyces cerevisiae D-71 cultured in Wickerham synthetic medium containing 0.5% of methionine and 0.1% of glucose to Zymolyase-20T was 66%, and $K_2$HPO$_4$ and aminobenzoic acid were greatly effective to susceptibility. Susceptibility of Zygosaccharomyces rouxii SR-S cultured in Wickerhnin synthetic medium containing 0.5% of peptone, 0.15% of methionine and 0.l% of glucose to Zymolyase-20T was 80%, and KI and pyridoxine were greatly effective to susceptibility. Susceptibility of Saccharomyces cerevisiae D-71 stationary cultured in YMPG medium at $25^{\circ}C$ for 12 hours was 16o1e and Zygosaccharomyces rouxii SR-S stationary cultured in YMPG medium at $25^{\circ}C$ for 30 hours was 82%.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.242-248
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• 1979

To detect proper lytic assay conditions of the crude zumolyase from Arthrobacter luteus, effets of the various factors involved in the lytic system of Sacchromyces sake cultured with shaking in the malt extracts medium were investigated. The results are summarized as follows : 1. The susceptibilities of viable cells of S. sake from logarithmic growth phase to the lytic enzmye were much greater than those of the cells in lag and stationary phases. The cells cultured for 18 hr were the most susceptible to the enzyme. 2. Lytic activity of the enzyme toward the viable cells of S. sake was very low. It was, however, enhanced 4 folds of more by the pretreatment of the cells with 0.05 M sodium sulfite. 3. Lytic activity of the enzyme toward commercial baker's yeast cells was negligible, and the effect of sodium sulfite on the lysis of the cells also was nothing but a little. 4. The lyophilized cells of the baker's yeast showed more susceptibility to the lytic enzyme than viable cells of the yeast. No definite effect of sodium sulfite on the lysis of the lyophilized cells, however, was observed either baker's yeast of S. sake. 5. It appeared that the relationship between the reaction rate and the enzyme concentration on the lysis of the yeast cell walls followed enzyme kinetic theory, but one between the reaction rate and concentration of the yeast cells as substrates showed different pattern from that in enzyme kinetic theory. 6. After the preparation of crude zymolyase was kept at $7^[\circ}C$ for 10 days in the 0.05 M phosphate buffer, pH 7.5, the remainning lytic activity was about 80 %.