• Korean Journal of Microbiology
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• v.19 no.2
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• pp.52-62
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• 1981

In order to interpret the effect of IAA on the phosphate metabolism and biosynthesis of organic compounds, Saccharomyces uvarum were cultured in the media treated with various concnetration of IAA $(10^{-3}M,\;10^{-5}M,\;10^{-7}M)$. Sampling at the beginning and intervals of culture, yeast cells fractionated were traced the contents of inorganic phosphate and organic compounds of various fractions. 1. Growth of Saccharomyces uvarum were enhanced by IAA $(10^{-3}M,\;10^{-5}M)$ and phosphate contents in DNA and RNA fractions treated with IAA were accelerated 2.3 times and 2 times in comparison with those of control. 2. Amounts of poly-P"A" and poly-p"B" were increased but poly-P"C" decreased during the culture. Therefore, it is considered that poly-P"C" play on most important role as a phosphate pool. 3. It is suggested that because phosphate contents in DNA, protein and lipid fractions increased, inorganic phosphates required phosphates required RNA were transferred from phosphates in cytoplasm, because these increased slowly during the culture. 4. Alkali-labile protein were accelerated by IAA and alkali stable protein only were inhibiction were enhanced by IAA while, ethanol : ether soluble fraction was induced by $10^{-7}M$ IAA in comparison with those control.X> IAA in comparison with those control.

• The Korean Journal of Mycology
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• v.14 no.3
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• pp.201-207
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• 1986

In order to study subcellular locality and characteristics of ribonuclease in Saccharomyces uvarum, subcelllar fractions $45,000{\times}g$ pellet fraction, post ribosomal fraction and ribosome fraction were extracted during late log, stationary phase and sugar starvation conditions. Ribonuclease activity was significantly increased in ribosomal fraction under stationary and sugar starvation conditions. Ribosomal ribonuclease was extracted by EDTA plus streptomycin sulfate and ammonium sulfate precipitation. The amount of ribosome in stationary and sugar starvation condition was decreased three to six fold as compared to that in the early log phase. The end products of ribosomal ribonuclease were detected by thin layer chromatography. It is postulated that the increase of ribosomal ribonuclease activity under sugar starvation results from 5'-rRNase, while the increase of rRNase activity under stationary phase results from 3'-rRNase.

• Preventive Nutrition and Food Science
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• v.2 no.1
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• pp.66-70
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• 1997

A mixed-culture of Gluconobacter suboxydans IFO 3172 and Saccharomyces uvarum IFO 0751 was per-formed in a synthetic medium. the optimal inculum ratio of G. suboydans and S. uvarum for mixed-culture fermentation was 150:1. The optimum pH, incubation temperature and aeration rate for mixed-culture fer- mentation were 5.0, 3$0^{\circ}C$ and 2.25vvm, reapectively. As a result of batch pure-and mixed-culture fer-mentation, specific growth rate in pure-culture of both strain was lower than that in mixed-culture. The yield of cell mass from S. uvarum exclusively decreased. The growth rate of the mixed-culture was very similar to the pure-culture in the begining of culture, but it has been decreased after 16hrs. In the mean time, S. uvarum in mixed-culture fermentation could grow due to fructose converted, but it could not row in pure-culture fermentation. Thus, the relationship was a sort of commensalism. The kinetic parameters cal-culated through steady-state results during continuous fermentations are as follows :{TEX}$$\mu$_{max1}${/TEX}=0.118({TEX}$h^{-1}${/TEX}), {TEX}$Ks_{1}${/TEX}=0.330(g/L),:{TEX}$$\mu$_{max2}${/TEX}=0.162({TEX}$h^{-1}${/TEX}), {TEX}$Ks_{2}${/TEX}=0.038(g/L). The yield of bacterial cell mass relatively constant, but yield of yest cell mass was gradually decreased.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.739-745
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• 1999

This study was carried out to investigate the oligosaccharide and amino acid utilization by mixed cultures during soy yogurt fermentation. Three types soy yogurt were prepared by fermenting with Lactobacillus acidophilus and Streptococcus thermophilus, Streptococcus thermophilus and Saccharomyces uvarum, Lactobacillus acidophilus and Saccharomyces uvarum. The utilized amount of oligosaccharide and amino acid was determined by HPLC during the fermentation period. The oligosaccharide and amino acid utilization efficiency of S. thermophilus and Sac. uvarum was greater than the other mixed cultures. It was found that Sac. uvarum produced enzymes which can convert oligosaccharide and common sugars in soy milk into glucose, galactose and fructose which can be fermented by L. acidophilus and S. thermophilus, and in turn stimulated acid production and amino acid utilization of the latter.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.84-89
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• 1985

The effect of exogenous phosphate supply on the regulation of phosphate metabolism was investegated during catabolic repression and catabolic derepression in yeast (Saccharomyces uvarum). As the results, when sugar was supplimented in cells cultivated under phosphate free, the growith rate was low but it was capable of cell division. Polyphosphate "B" was accumulated highly in proportion to amount of phosphate added to the medium. Without regard to phosphate supply of the medium, the total amount of polyphospgate was almost similar, although each polyphosphate was turned over. Activities of all phosphatases remained continuousoy high in the cells cultivated in the phosphate free medium. Especially under catabolic repression, the function of polyphosphate system was shown to compensate the ATP/ADP system as phosphate donor, energy source and regulator.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.33-38
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• 1983

As flocculent strains are likely to have considerable potential for internal cell recycle, kinetic studies on glucose medium with flocculent Saccharomyces uvarum were carried out in batch and continuous culture. Using a mathematical model, the kinetic parameters at each temperature and pH were estimated in order to establish optimal conditions. It was found that an overall optimum temperature for growth and ethanol production in the range 33-35$^{\circ}C$ was desirable. With regard to the effect of pH, ethanol production by S. uvarum was found to be relatively insensitive to pH value between 4 and 6, with an optimum pH of around 5. At these optimal conditions a maximum ethanol productivity of 12 g/$\ell$/h was determined using semi-batch process together with 5. uvarum.

• Food Science and Preservation
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• v.31 no.1
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• pp.197-198
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• 2024

• The Korean Journal of Mycology
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• v.13 no.3
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• pp.141-148
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• 1985

To investigate cellular regulation of phosphate metabolism between catabolically repressed and derepressed states in Saccharomyces uvarum, the activities of polyphosphatases, the analysis of polyphosphate and cytochemical observation of volutin granules were examined according to the culture phase and under various phosphate concentrations. As the results, tripolyphosphatase activity was increased more than six-fold during catabolic repression as compared with those of catabolic derepression and the polyphosphatase activity increased at the time of maximal accumulation of acid insoluble polyphosphate 'B'. Of the low molecular weight polyphosphates, tripolyphosphate was mainly detected by thin layer chromatography. When the synthesis of volutin granules in derepressed cells was observed cytochemically, acid insoluble polyphosphate localizing at the cell wall was primarily synthesized and then transferred into the cytoplasm, nucleus and/or vacuole.

• Korean Journal of Food Science and Technology
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• v.19 no.4
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• pp.355-360
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• 1987

Among the several lactic acid bacteria, Lactobacillus acidophilus showed the highest acid production when it was cultured mixed with Sacchasomyces uvarum in soymilk. The highest acid production was obtained in 16 hrs of cultivation when the inoculation ratio of L. acidophilus and S. uvarum was 2:1 and the temperature was $30{\sim}37^{\circ}C$. The acid production was greatly enhanced by the addition of 2.0% sucrose. However, skim milk was not stimulatory in mixed culture. During mixed culture in soymilk, acid production was affected by the enzymatic reaction of yeast.

• Journal of Ginseng Research
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• v.5 no.2
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• pp.139-147
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• 1981

The effect of ginseng extract and ginseng saponins on alcoholic fermentation was studied 1. Alcoholic fermentation on gllicose medium at 30$^{\circ}C$. by Saccharomyces coveanus and Saccharomyces uvavum was stimulated when the media contained 5% and 10 % of ginseng extract, respectively. But that of Saccharomyces cerevisiae was inhibites by the addition of 10% of ginseng extract. 2. Saponin did not stimulate the alcoholic fermentation by Saccharomyces uvarum. 3. The yeast cell counts was increased remarkably by addition of ginseng extract while that of ginseng saponins was increased slightly. Dried cell weight of the broth which Contained 5% of ginseng extract was 3 times than that of control.