• Applied Biological Chemistry
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• v.28 no.3
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• pp.196-201
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• 1985

Several interesting aromas could be produced from the cultures of Saccharomyces cerevisiae depending on the amino acids used as sole nitrogen source. The yeast produced a fusel oil odor in leucine-medium, an aroma of traditional Korean rice wine in aspartic acid-medium and a floral note in phenylalanine-medium, respectively, Ethanol, iso-amyl alcohol, iso-butanol and n-propanol were found as major volatile con stituents in all the above three cultures. In addition to these compounds, phenethyl alcohol was present as major volatiles both in the aroma concentrates of the phenyl alanine and aspartic acid cultures, and phenethyl acetate only in the phenylalanine culture.

• Journal of Life Science
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• v.18 no.7
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• pp.947-951
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• 2008

Zinc is an essential trace element participating in many physiological functions and notably an important function for sperm physiology. Zinc-enriched yeast strain, Saccharomyces cerevisiae, isolated from tropical fruit rambutan. This strain contained 306 ppm zinc concentration and other components contained by K 28,640 ppm, Mg 2,342 ppm, Na 1,048 ppm, Ca 366 ppm, Fe 236 ppm and Mn 4 ppm. The serum concentration of testosterone was decreased in ethanol treatment rats. As compared with ethanol treated control rats, the zinc-enriched yeast strain supplementation showed significantly increased the testosterone concentration in serum. In addition, zinc concentration in serum was decreased in alcohol treatment, but this reduction was significantly increased by zinc-enriched yeast strain supplementation in ethanol feeding rats. These results indicate that zinc-enriched yeast Saccharomyces cerevisiae strain could play an important role in the sperm physiology by the marked elevation of serum testosterone concentration.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.826-830
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• 2018

A Cre/loxP-${\delta}$-integration system was developed to allow sequential and simultaneous integration of a multiple gene expression cassette in Saccharomyces cerevisiae. To allow repeated integrations, the reusable Candida glabrata MARKER (CgMARKER) carrying loxP sequences was used, and the integrated CgMARKER was efficiently removed by inducing Cre recombinase. The XYLP and XYLB genes encoding endoxylanase and ${\beta}$-xylosidase, respectively, were used as model genes for xylan metabolism in this system, and the copy number of these genes was increased to 15.8 and 16.9 copies/cell, respectively, by repeated integration. This integration system is a promising approach for the easy construction of yeast strains with enhanced metabolic pathways through multicopy gene expression.

• Korean Journal of Microbiology
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• v.28 no.2
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• pp.120-127
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• 1990

Intraspecific fusion frequency between Filobasidium capsuligenum CBS6122-2 ade and met trp or met strains was $2.9\times 10^{-3}$ and $8.5\times 10^{-3}$, respectively. And intergeneric fusion frequency between Folobadidium capsuligenum CBS 4318 (cys his) and Saccharomyces cerevisiae 262-12-1 (hom3 thr1) or X2180-1A (ade thr) was $8.8\times 10^{-6}$ and $9.5\times 10^{-4}$, respectively. Nuclear fusion appears to occru in fusants between intraspecies and intergenera as strongly suggested by DNA content, nuclear staining, comparison of survival rate to UV light and mitotic segregation analysis. It was also found that $\alpha$-amylase and glucoamylase activity from intraspecific hybrids was 1.6-2.1 fold increased when compared with that from thier parents.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1597-1604
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• 2006

To screen for an anti-yeast substance (AYS), many bacteria were isolated from soil and a strain AY2000 was selected. The strain AY2000 was identified as Rahnella aquatilis by morphology, biochemical properties, and 16S r-RNA nucleotide sequence analyses. The strain AY2000 showed anti-yeast activity against Candida albicans and Saccharomyces cerevisiae, whereas R. aquatilis ATCC33071 as a type strain did not show the activity against the yeasts under the same condition. The growth of yeast cell was significantly inhibited by AYS produced by the strain AY2000, as shown by optical density and MTT assay. The minimum inhibitory concentration (MIC) of the AYS against S. cerevisiae and C. albicans at $28^{\circ}C\;was\;20{\mu}g/ml\;and\;60{\mu}g/ml$, respectively. The MIC of AYS against hyphae of C. albicans at $37^{\circ}C\;was\;600{\mu}g/ml$. Scanning electron microscopic analysis revealed that yeast cells treated with AYS had an irregular form with a wrinkled and rough surface.

• Microbiology and Biotechnology Letters
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• v.2 no.2
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• pp.83-88
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• 1974

The water pollution by waste water is one of the important issue and the short of animal feed is too, in Korea. So, this experiment is accomplished to treat alcohol distillers' waste by micro-organisms and planning to produce yeasts, which can be used as animal feed, pharmacy and condiments. 1. The raw material, alcohol distillers' waste, of this experiment consists of insoluble solids (residue) and filterate (supernatant). The residue contains 33.08％ of crude protein, 19.96％ of total sugar. and 2.06％ of ash, respectively. On the other hand the flterate through the Toyo filter paper No. 5C, contains 2.48％ of crude protein, 1.54％ of reducing sugar, and 0.43％ of ash, respectively. 2. Optimum pH of the basal medium for the growth of Saccharomyces cerevisiae YF-1 is 4.0. Optimum culture condition of this is as follows : when 0.43g of urea, 0.43g of potassium phosphate monobasic, and 0.21g of magnesium sulfate are added to the 100m1 of basal medium. Optimum temperature and optimum incubation time are 30$^{\circ}C$ and 24-28 hrs. 3. Under these conditions, the maximum yield of dry yeast is 1.38％ to the medium. 4. The composition of dry yeast, produced under these conditions, is as follows: crude protein, 56.96％, lipid, 1.30％. total sugar, 6.53％, and ash 9.62％.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.4
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• pp.307-318
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• 2005

This study was conducted to examine effects of brewery meal-based fermented feedstuff supplemented with Aspergillus oryzae(AO) or Saccharomyces cerevisiae(SC) on luminal micro-organism of Korean native cattle. Two cows equipped with luminal cannulas were used as experimental animals. Experiment was done with three treatment groups: $71.5\%$ of commercial feed and $28.5\%$ of com silage(control): $45.0\%$ of commercial feed, $26.5\%$ of fermented feedstuff supplemented with AO and $28.5\%$ of corn silage(TAO): $45.0\%$ of commercial feed, $26.5\%$ of fermented ffedstuff supplemented with SC and $28.5\%$ of corn silage(TSC). The number of total viable bacteria (p<0.05), anaerobic fungi and protozoa(p<0.05) was higher in TAO and TSC than in control. The number of proteolytic bacteria(p<0.05), cellulolytic bacteria and xylan fermenters tended to be higher in TAO and TSC than in control. The dry matter recovery (DMR) of protozoa was higher in TAO and TSC than in control(p<0.05). The crude protein (CP) content of total microbes and protozoa was higher in TSC than in control and TAO (p<0.05). The CP content of bacteria was higher in TAO and TSC than in control(p<0.05). The ether extract(EE) content of the total microbes was higher in TAO than in control and TSC(p<0.05), and the EE of protozoa and bacteria were higher in TSC than in control and TAO(p<0.05). The ratio of essential amino acids of total microbe was higher in control than in TAO and TSC(p<0.05). The ratio of methionine and alanine of bacteria was higher in TAO and TSC than in control(p<0.05). The results suggested that the feeding of fermented feedstuff supplemented with AO or SC had an influence on the numbers of ruminal microorganism and the changes of microbial body composition.

• Korean Journal of Microbiology
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• v.52 no.1
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• pp.98-109
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• 2016

The study was aimed to investigate the mixing ratio of kiwi and persimmon juices for the production of good quality wine by Saccharomyces cerevisiae Y28. Firstly, the optimum condition of rapidase treatment for the kiwi and persimmon juices was established, thereafter various mixing ratio (10:0, 9:1, 8:2, 7:3, 6:4, 5:5) of kiwi and persimmon was investigated regarding physiochemical properties and flavor compounds of wine. As the result, the optimum conditions were obtained as 0.3% rapidase for 1 h in kiwi and 0.3% rapidase for 3 h in persimmon. According to higher ration of persimmon, the pH of wines increased from 3.69 to 3.77, while the acidity of wines decreased from 2.07% to 1.51% at 14 days fermentation. The ranges of brix and reducing sugar in wines were decreased which ranges around 9.6 to 8.8 and 6.07 to 6.90 g/L, respectively, after fermentation. Major organic acid in wines were identified as tartaric acid, malic acid, and citric acid. A small amount of free sugar such as sucrose and glucose were detected in wines, but fructose was completely absent. The soluble phenolic contents were decreased that ranges around 1.00 to 1.25 g/L, in contrast, browning degree were increased ranges around 0.212 to 0.412 after fermentation. The major flavor components were identified as ethyl acetate and hydrazine, and 1,1-dimethyl. Importantly, phenylethyl alcohol was detected from the all wines that have a typical rose like flavor. But sensory test results and preference of kiwi-persimmon (7:3) mixing wine was better than the other wines.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1026-1032
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• 2015

This study attempted to find an efficient method for the preparation of high-purity galactooligosaccharides (HP-GOS) using ${\beta}$-galactosidase and yeast fermentation. GOS prepared using Lactozym 3000L showed the greatest enhancement in total GOS of the six ${\beta}$-galatosidases tested. GOS alone achieved 51% conversion of initial lactose. GOS production was enhanced by fermentation with commercial yeast (Saccharomyces cerevisiae); its concentration reached 71% after 36h fermentation with 8% yeast. Component sugar analysis with HPLC indicated that HP-GOS fermented with S. cerevisiae showed significantly increased levels of 4'/6'-galactosyllactose and total GOS as well as a significantly decreased glucose level. HP-GOS facilitated the growth of Lactobacillus sp. (L. acidophilus and L. casei) and Bifidobacterium sp. (B. longum and B. bifidum). In sum, high-purity GOS has been successfully produced through both an enzymatic process and yeast fermentation. GOS encourages the growth of bacteria such as Lactobacillus and Bifidobacterium that may be beneficial to human gastrointestinal health.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.187-191
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• 1970

This experiment was carried out to isolate osmophilic yeasts for higher concentration of NaCl than 20 per cent may affect greatly the fermentation of soy sauce. 6 strains of yeasts were selected from the soy sauce mashes at the fermentating periods and identified observing their morphological characteristics. Their salt-resistance and effects upon the flavor of soy sauce were examined. The results obtained were as follows: (1) The strain $T_3,T_5,$ and $T_{11},\;T_8,\;T_9,\;and\; T_{10},$ selected were identified Saccharomyces cerevisiae group II, Debaryomyces nicotianae, Saccharomyces chevalieri, Saccharomyces rouxii and Saccharomyces rosei, respectively. (2) They were more salt-resistant on the liquid media than on the solid media in the case of cultures on the media containing more than 26 per cent of NaCl. (3) They were grown on the media containing 5-23 per cent of NaCl better than containing none of NaCl. (4) The strain $T_3,\;T_8,\;T_9,\;and\; T_{10}$ were grown on the media containing up to 28 per cent of NaCl, and $T_5\;and\;T_{11}$ up to 32 per cent of NaCl is the case of liquid cultures. (5) Among them, the strain $T_9$ showed the best alcohol fermentation ability and the best fermentative flavor, and $T_5\;and\;T_{11}$ formed moldy smell and pellicle.