• Journal of Life Science
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• v.23 no.2
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• pp.222-227
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• 2013

An effective leavening yeast was isolated from raisin broth. The isolate was identified as Saccharomyces cerevisiae by comparing the homology of 18S rDNA ITS sequences and named as S. cerevisiae MF10003. S. cerevisiae MF10003 showed a 1.9-fold and 3.1-fold increase in $CO_2$ production and leavening ability, respectively, compared with the wild yeast S. ellipsoideus KCTC7243, and the dough had a rich and volatile flavor. When glucose, sucrose, fructose, and maltose were added to the culture broth as a carbon and energy source, $CO_2$ was produced in 4 hr.

• Microbiology and Biotechnology Letters
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• v.14 no.3
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• pp.213-218
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• 1986

Hybrid plasmid pEA24, shuttle vector YRp7 carrying amylase gene of Bacillus amyloliquefaciens, was transformed to yeast Saccharomyces cerevisiae, and the expression of B. amyloliquefaciens amylase gene in yeast was investigated. The frequency of transformation to S. cerevisiae DBY747 with YRp7 was increased by treatment of 40% polyethylene glycol (MW 4, 000), PH 7.0, at 3$0^{\circ}C$, and by regeneration used 2% top agar. The amount of cellular amylase activity produced by S. cerevisiae containing pEA24 was 2% of that secreted from B. amyloliquefaciens, but in case of S. cerevisiae transformant, the amylase secreted was not detected. A comparison of genetic stability of pEA24 and YRp7 plasmids in yeast was carried out by cultivation of transformants in tryptophan-supplement-medium. The pEA24 plasmid was more unstable than YRp7 in S. cerevisiae. The size of pEA24 extracted from S. cerevisiae transformants was found to be identical with that from E. coli transformants by agarose gel electrophoresis.

• 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%.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.293-297
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• 2002

The cyclodextrin glucanotransferase (CGTase) gene from Bacillus stearothermophilus NO2 was expressed in Saccharomyces cerevisiae 2805 under the adhl promoter. The CGTase was purified from S. cerevisiae 2805/pVT-CGTS. The purified enzyme exhibited a optima of activity around pH 7.0 and $65^{\circ}C$. Thermal stability of the enzyme was increased fairly as compared with the CGTase of B. stearothermophilus NO2. The conversion yield of cyclodextrin (CD) and the production ratio of $\alpha$-, $\beta$,-, ${\gamma}$-CD from starch were showed similarly aspect to the CGTase of B. stearothermophilus NO2.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.21-25
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• 1997

A study on the removal of mercury by Saccharomyces cerevisiae and Aureobasidium pullulans was done, in which the model of adsorption isotherm and adsorption rate was proposed. The adsorption isotherm of mercury by S. cerevisiae was accorded with Langmuir model but A. pullulans was followed to Freundlich model. The amount of mercury removed by A. pullulans was higher than that of S. cerevisiae, but the adsorption rate of mercury by A. pullulans was slower than that of S. cerevisiae. In a rapid adsorption process, therefore, it is more useful to use S. cerevisiae as a biosobent.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.73-80
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• 2004

Coenzyme Q is a quinone derivative that acts as a lipid electron carrier in the respiratory chain located at mito-chondrial inner membrane in eucaryotes or plasma membrane in procaryotes and also functions as antioxidant. A putative Neurospora crassa coq-4 gene was cloned and functionally expressed in Saccharomyces cerevisiae coq4 mutant. Complemented S. cerevisaie mutant strain was able to produce coenzyme $Q_{6}$ and showed a normal growth rate. They also showed less sensitivities to polyunsaturated fatty acids such as linoleic acid or linolenic acid. The predicted sequence of N. crassa COQ4 is consisted of 347 amino acids with a molecular mass of 39.7 kDa and showed 35% identity and 52% similarity with that of S. cerevisiae.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.131-135
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• 1988

Lactobacillus acidophilus KFCC12731 and Saccharomyces cerevisiae KFCC32017 were incubated together in soymilk and the conditions for acid production were investigated. The acid production of Lactobacillus acidophilus was much higher when this organism was incubated with Saccharomyces cerevisiae in soymilk than when it was incubated alone. Optimum acid production by the mixed cultures of Lactobacillus acidophilus and Saccharomyces cerevisiae was achieved with the following conditions; a temperature of 34$^{\circ}C$, a 3:7-8:2 (OD 660) ratio of Lactobacillus acidophilus to Saccharomyces cerevisiae at inoculum, a 1.5% level of sucrose fortification or a 2.0-3.0 % level of skim milk powder fortification and a culture time of 12 hours or more.

• Food Science and Biotechnology
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• v.17 no.6
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• pp.1160-1164
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• 2008

An novel amylolytic yeast, Saccharomyces cerevisiae HA 27, isolated from nuruk, displayed resistance against high sugar (50% glucose) and alcohol (15%). Maximal production of amylolytic enzyme by S. cerevisiae HA 27 was achieved on 9 days of cultivation at the optimal temperature $20^{\circ}C$ and pH 6.0. The activity of amylolytic enzyme produced by S. cerevisiae HA 27 was stable, even at $70^{\circ}C$, and over a broad pH range (4.0-11.0). Also, the amylolytic enzyme of S. cerevisiae HA 27 showed optimal activity in pH 5.0 at $50^{\circ}C$. S. cerevisiae HA 27 exhibited 6.2%(v/v) alcohol fermentation ability using starch as a carbon source.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.753-757
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• 2003

Escherichia coli and Saccharomyces cerevisiae have been used as host for production of recombinant proteins. It is known that S. cerevisiae has advantages such as good folding and secretion capability, and safety as host over E. coli. But S. cerevisiae has shortcomings of low expression level which is just 20% of that of E. coli. To solve this problem, directed evolution method was tried to enhance the GAP promoter strength of S. cerevisiae in this study. As result, modified GAP promoter that has increased expression level of about 360% compared to that of wild type was selected.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.878-884
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• 1995

In order to use whey lactose in alcohol fermentation, we investigated fermentation conditions of Saccharomyces cerevisiae and Kluyveromyces fragilis in lactose-hydrolyzed whey with ${\beta}-D-galactosidase$. and optimum conditions of the above two yeasts through oxygen regulation by Pasteur effect which is the characteristic of the yeasts were determined. In addition, optimum condition for application of fermented whey in Tak-ju process was also examined. With 0.7% ${\beta}-D-galactosidase$, 93% lactose was hydrolyzed at pH 6.5 in 30 minutes. Because S. cerevisiae is unable to ferment galactose, the production of ethanol by S. cerevisiae was lower than that of K. fragilis in lactose-hydrolyzed whey. But ethanol productivity by S. cerevisiae was higher than that by K. fragilis in glucose added whey. In fermentation with oxygen regulation and addition of 60 g/l glucose, the ethanol productivity of K. fragilis and S. cerevisiae were 18.9 g/l (11.8% increase) and 43.5 g/l (22.1% increase), respectively. It appeared that the ethanol productivity of S. cerevisiae was higher than thst of K. fragilis under the above conditions. In ethanol fermentation added rice starch, Aspegillus oryzae hydrolyzed 80% of starch in 60 hours, and the production of ethanol was 80.2 g/l