• Journal of Ginseng Research
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• v.18 no.1
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• pp.49-52
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• 1994

A yeast was isolated from the spoiled ginseng product. The isolate was ellipsoidal shaped yeast measured around 2.0 to 2.5 w in diameter. The strain formed pseudomycelium on potato-dextrose agar medium. The isolated yeast used glucose as fermentable sugar, and showed assimilation activity for glucose, sorbitol and mannitol. The strain was also able to grow in the presence of 1% acetic acid and 50% (w/v) glucose-yeast extract agar. The isolated osmophilic yeast was identified as a strain of Zygosauharomyce sp.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.555-564
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• 2019

Biodiesel is produced through the transesterification process in the presence of alcohol and a catalyst that catalyzes the conversion of triglycerides to esters and glycerol compounds. A more optimal product conversion can be achieved using enzymes, such as lipase. Lipase is reported to be produced in osmophilic yeasts due to the low water content in their natural habitats. Wild forest honey is one of the osmophilic natural habitats in Indonesia. However, lipase-producing yeast has not been reported in the Indonesian honey. In this study, we screened the lipase-producing yeasts isolated from wild forest honey collected from Central Sulawesi. The production profile and activity of lipase were determined at different pH values and temperatures. One promising yeast was isolated from the honey, which was identified as Zygosaccharomyces mellis SG 1.2 based on ITS sequence. The maximum lipase production (24.56 ± 1.30 U/mg biomass) was achieved by culturing the strain in a medium containing 2% olive oil as a carbon source at pH 7 and 30℃ for 40 h. The optimum pH and temperature for lipase activity were 6 and 55℃, respectively. The enzyme maintained 80% of its activity upon incubation at 25℃ for 4 h. However, the enzyme activity decreased by more than 50% upon incubation at 35 and 40℃ for 2 h. This is the first study to report the lipase producing capability of Z. mellis. Further studies are needed to optimize the enzyme production.

• Korean Journal of Microbiology
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• v.8 no.3
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• pp.103-106
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• 1970

The cultural conditions of the osmophilic red color yeasts (Strain L${1$, $L_2$, $L_3$ and $L_4$) isolated and identified in the previous report were examined and the results obtained were as follows ; 1. The optimum medium for growth of these osmophilic red color yeasts was soy sauce medium. 2. These strains were grown exceedingly well on the medium containing 3 percent of NaCl but somewhat restrained on the medium containing 6% or more. 3. The optimum temperautre for growth of these strains was $25^{\circ}C$ and their lethal temperature was $68^{\circ}C$(treatment for 5 minutes). 4. The optimum pH for growth of these strains was 6.0.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.708-712
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• 2003

This study was carried out to examine the effects of fermentation conditions on the production of erythritol by osmophilic yeast Candida magnoliae. It was found that sucrose was superior to glucose as carbon source and 109 g/L erythritol was produced from 400 g/L sucrose. When yeast extract was used as nitrogen source, maximum values of yield and productivity for erythritol were obtained at 15 and 20 g/L of yeast extract, respectively. A mixture of 15 g/L yeast extract and 3 g/L ammonium phosphate allowed more efficient utilization of sucrose and hence resulted in 149 g/L of erythritol, 0.37 g erythritol/g sucrose of erythritol yield and $0.78\;g/L{\cdot}hr$ of erythritol productivity. A batch fermentation supplemented with 40 g/L KCl resulted in an erythritol concentration of 167 g/L and an erythritol yield of 0.42 g erythritol/g sucrose.

• Korean Journal of Microbiology
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• v.9 no.2
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• pp.55-60
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• 1971

Among 50 yeasts of red pepper paste isolated and identified in the previous report, 12 strains of yeast which possess osmophilic and non-film characteristics were examined their growth rates and alcohol fermentation ability in red pepper medium. 5 strains of yeast possessing powerful growth rates and excellent alcohol fermentation ability were selected as excellent yeasts in this experiment. And their cultural conditions, salt resistance and red pepper concentration upon the growth were examined in this report. The results obtained were as follows ; 1) Among 12 strains of yeast, Saccharomyces cerevisiae group II(strain $D_1$), Saccharomyces oviformis($D_2$), Saccharomyces steineri($M_3$), Saccharomyces rouxii($D_9$) and Saccharomyces mellis($G_8$) were selected as excellent yeasts. 2) Among 5 strains of yeast selected, the strain $D_1$ and $D_2$showed the best alcohol fermentation ability and the best fermentative flavour. 3) The optimum temperature for growth of the strain $D_1$ and $D_2$ was $25^{\circ}C$$M_3$, $D_9$ and $G_8$ $30^{\circ}C$$D_1$ and $D_2$ was $62^{\circ}C$$M_3$,$D_9$ and $G_8$ ws 60.deg.C with treatment for 10 minutes. 4) The optimum pH for growth of all strains was around 5.0. 5) The strain $D_1$ and $M_3$were grown exceedingly well on the emdia containing 3 percent of NaCl and $D_2$,$D_9$ and $G_8$ on the media containing 6 percent of NaCl. 6) In the case of 5 percent of red pepper liquor added 5 percent of glucose was more nutritional than in the case of 5 percent glucose only. However, the growth rates of yeasts were restrained by the increase of red pepper concentration.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.272-276
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• 2005

Candida tropicalis, an osmophilic strain isolated from honeycomb, produced xylitol at a maximal volumetric production rate of 3.5 g $l^{-1}$ $h^{-1}$ from an initial xylose concentration of 200 g $l^{-1}$. Even with a very high xylose concentration, e.g., 350 g $l^{-1}$, this strain produced xylitol at a moderate rate of 2.07 g $l^{-1}$ $h^{-1}$. In a fed-batch fermentation of xylose and glucose, 260 g $l^{-1}$ of xylose was added, and xylitol production was 234 g $l^{-1}$ for 48 h, corresponding to a rate of 4.88 g $l^{-1}$ $h^{-1}$. To increase the xylitol production rate, cells were recycled in a submerged membrane bioreactor with suction pressure and air sparging. In cell-recycle fermentation, the average concentration of xylitol produced per recycle round, total fermentation time, volumetric production rate, and product yield for ten rounds were 180 g $l^{-1}$, 195 h, 8.5 g $l^{-1}$ $h^{-1}$, and 85%, respectively. When cell-recycle fermentation was started with the cell mass contratrated two-fold after batch fermentation and was performed for ten recycle rounds, we achieved a very high production rate of 12 g $l^{-1}$ $h^{-1}$. The production rate and total amount of xylitol produced in cell-recycle fermentation were 3.4 and 11 times higher than in batch fermentation, respectively.

• Applied Biological Chemistry
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• v.14 no.2
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• pp.121-129
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• 1971

During the Brewing of Soy Sauce on an industrial scale, Saccharomyces rouxii $T_9$ was cultured and added to the soy sauce mash. The comparative experiments of soy sauce mash in non-addition and addition group of yeast were examined in this report. The yeast flora and chemical composition of Soy sauce mash through out the brewing were observed and the results obtained were as follows. (1) The number of Osmophilic yeast in one ml of soy sauce mash showed $185{\times}10^3$ 1 month after mashing and $750{\times}10^3$ 4 months after mashing in case of yeast group, while presented as $98{\times}10^3$ 1 month after mashing and $394{\times}10^3$ 4 months after mashing in case of non-yeast group. And the number of Osmphilic yeast in yeast group was twice of that in non-yeast group. (2) The number of ordinary yeast of TTC red group was shown as $2132{\times}10^3\;to\;3252 ×10^3$ 5 to 6 months after mashing in case of yeast group, while presented $752{\times}10^3\;to\;1251{\times}10^3$ in case of non-yeast group. And the yeast group was shown more than non-yeast group in ordinary, red pink and pink yeast number. (3) TTC red yeast were strongly appeared in both addition and non-addition group of yeast from 1 month after mashing to 6 months after mashing. (4) Though total nitrogen, pure extract, pH and buffer action contents of soy sauce showed similiar tendency in yeast and non-yeast group, alcohol and color density contents were highly appeared in yeast group and reducing sugar content was in non-yeast group respectively. (5) By the results of Organic function test of soy sauce mash, the difference of taste quality in yeast and non-yeast group were not evidently appeared, however, the appearance and flavour of the soy sauce were better in yeast group than in non-yeast group.

• Journal of Microbiology and Biotechnology
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• v.8 no.5
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• pp.543-546
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• 1998

The effect of glucose concentration on the production of erythritol by Trichosporon sp. was mainly studied. The specific growth rate and production rate of erythritol gave the highest values of $0.23 h^{-1}\; and\; 4.2 g/\ell/h,\; respectively,\; on\; 100 g \; glucose/\ell$ of medium. The conversion yield of erythritol during the exponential phase and the stationary phase was constantly maintained at 19% and 51 %, respectively, while the glucose concentration in the medium varied from 100 g/$\ell$ to 400 g/$\ell$. The maximum overall erythritol conversion yield of 47% was obtained when the glucose concentration in the medium was 400 g/$\ell$. It corresponded to a 74% increase compared with the 100 g/$\ell$ glucose medium. The diauxy growth of this microbe was also observed. It grew exponentially consuming glucose, then after the second lag phase, biomass slowly increased using glycerol and erythritol.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1056-1069
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• 2015

Osmotic pressure is a critical factor for erythritol production with osmophilic yeast. Protein expression patterns of an erythritol-producing yeast, Yarrowia lipolytica, were analyzed to identify differentially-expressed proteins in response to osmotic pressure. In order to analyze intracellular protein levels quantitatively, two-dimensional gel electrophoresis was performed to separate and visualize the differential expression of the intracellular proteins extracted from Y. lipolytica cultured under low (3.17 osmol/kg) and high (4.21 osmol/kg) osmotic pressures. Proteomic analyses allowed identification of 54 differentially-expressed proteins among the proteins distributed in the range of pI 3-10 and 14.4-97.4 kDa molecular mass between the osmotic stress conditions. Remarkably, the main proteins were involved in the pathway of energy, metabolism, cell rescue, and stress response. The expression of such enzymes related to protein and nucleotide biosynthesis was inhibited drastically, reflecting the growth arrest of Y. lipolytica under hyperosmotic stress. The improvement of erythritol production under high osmotic stress was due to the significant induction of a range of crucial enzymes related to polyols biosynthesis, such as transketolase and triosephosphate isomerase, and the osmotic stress responsive proteins like pyridoxine-4-dehydrogenase and the AKRs family. The polyols biosynthesis was really related to an osmotic response and a protection mechanism against hyperosmotic stress in Y. lipolytica. Additionally, the high osmotic stress could also induce other cell stress responses as with heat shock and oxidation stress responses, and these responsive proteins, such as the HSPs family, catalase T, and superoxide dismutase, also had drastically increased expression levels under hyperosmotic pressure.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.201-207
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• 1998

In order to evaluate the effects of addition of soybean boiling waste liquor (SBWL) and sugar and inoculation of the lactic acid bacteria and yeast starter culture in Korean traditional kanjang mash, three types of kanjang were prepared in a clay pot of 100 l volume and compared the characteristics of lactic acid fermentation. The mashing compositions of the types of kanjang were as follows: (1) control treatment mash was prepared with meju : 20% salt solution (1:4) and SBWL, (2) kanjang mash with 3.5% added sugar to the control type mash and (3) kanjang mash with 3.5% added sugar and inoculation of the lactic acid bacteria and yeast starter culture 35 days after mashing to the control type mash. (1), (2) and (3) of kanjang mash were found to be effective in increasing the lactic acid content and improving the organoleptic characteristics of kanjang. But the effect of yeast starter culture was not clear because osmophilic yeasts were inhibited by metabolite(acetic acid) produced by lactic acid bacteria. The lactic acid content of (1), (2) and (3) kanjang was 2.05, 2.38 and 2.91% respectively in 90 day-matured kanjang.