• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.41-44
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• 2000

Fermentation characteristics of recombinant Saccharomyces cerevisiae containing the xylose reductase gene from Pichia stipitis were analyzed in an attempt to convert xylose to xylitol, a natural five-carbon sugar alcohol used as a sweetener. Xylitol was produced with a maximum yield of 0.95 (g xylitol/g xylose consumed) in the presence of glucose that is used as a cosubstrate for cofactor regeneration. However addition of glucose caused inhibition of xylose transport and accumulation of ethanol. Such problems were solved by adopting glucose-limlted fed-batch fermentation. This process done with S, cerevisiae EHl3.15:pY2XR at$30\;^{\circ}C$ resulted in 105.2g/L xylitol concentration with maximum productivity of 1.69 g $L^{-1}$ $hr^{-1}$.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.120-122
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• 2005

Phospholipases C (PLCs) from B. cereus 318 and recombinant Pichia pastoris were immobilized on sol-gel coated glass beads. The pH and temperature on immobilized PLC activity were investigated. Operational and storage stability of the immobilized PLCs was measured by spectro- photometric assay. The PLCs immobilized on sol-gel coated glass beads were photographed by scanning electron microscope (SEM).

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.435-438
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• 2003

Epoxide hydrolase(EH) catalyze the enantioselective hydrolysis of racemic epoxides to corresponding diols. A recombinant Pichia pastoris with EH from Rhodotorula glutinis has been constructed by reverse transcriptase-polymerase chain reaction(RT-PCR). The recombinant biocatalyst enantioselectively hydrolyze (R)-styrene oxide faster than (S)-enantiomer. The catalytic activity of recombinant biocatalyst was 7-fold higher than that of wild-type strain. The recombinant EH biocatalyst can be used for kinetic resolution for the production of enantiopure styrene oxide.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.264-269
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• 2014

For the production of ethanol from seaweed as the source material, thermal acid hydrolysis and enzymatic saccharification were carried out for monosugars production of 25.5 g/l galactose and 7.6 g/l glucose using Gelidium amansii. The fermentation was performed with Pichia stipitis KCTC 7228 or Saccharomyces cerevisiae KCCM 1129. When wild P. stipitis and S. cerevisiae were used, the ethanol productions of 11.2 g/l and 6.9 g/l were produced, respectively. The ethanol productions of 16.6 g/l and 14.6 g/l were produced using P. stipitis and S. cerevisiae acclimated to high concentration of galactose, respectively. The yields of ethanol fermentation increased to 0.5 and 0.44 from 0.34 and 0.21 using acclimated P. stipitis and S. cerevisiae, respectively. Therefore, acclimation of yeasts to a specific sugar such as galactose reduced the glucose-induced repression on the transport of galactose.

• Microbiology and Biotechnology Letters
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• v.25 no.5
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• pp.435-441
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• 1997

Forty seven strains of yeast were isolated from traditional Meju and were identified as Saccharomyces spp. (7 strains), Zygosaccharomyces spp. (7 strains), Kluyveromyces spp. and Hansenula spp. (each 5 strains), Rhodotorular spp. (8 strains), Candida spp. (12 strains), Pichia spp. and Debaryomyces spp. from results of their microbiological characteristics. The optimal medium for growth of all the yeasts was YM media and the optimal initial pH of the medium was 6.0. The optimum temperature for growth was 30$circ$ and among them, Sacch. exiguus OE-5, Sacch. cerevisiae OE-16, Sacch. kluyveri C-1 strains were thermotolerant yeasts which could grow at 40$circ$C.

• KSBB Journal
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• v.4 no.2
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• pp.69-73
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• 1989

Batch fermentation runs were made with initial xylose concentrations of 2%, 4%, 8%, and 10%. The maximum yields were 0.46, 0.45, 0.43, and 0.42g ethanol/g xylose for 2%, 4%, 8%, and 10% xylose respectively. Xylitol formation was insignificant over a wide range of sepcific oxygen supply rates and xylose concentrations. The maximum specific productivities were 0.110, 0.110, 0.241, and 0.0961g ethanol/hr-g DCW for 2% through 10% xylose concentration.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.199-204
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• 2009

Three plant growth-promoting yeasts and two rhizobacteria were tested for controlling tomato wilt caused by Fusarium oxysporum f. sp. lycopersici under green-house and field conditions. Under greenhouse and field conditions, all treatments were significantly reduced disease severity of tomato wilt relative to the infected control. The highest disease reductions in pots (75.0, 67.4%) and field (52.5, 42.4%) were achieved by Azospirillum brasilense and Bacillus subtilis compared to infected control. Under field condition all treatments produced the highest tomato yield compared to the control plants inoculated with the pathogen.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.2
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• pp.95-102
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• 1981

From various sources of natural habitat yeasts, which coo 14 transform the constituents of tobacco Powder into flavors, were isolated and three isolates. YOII, M4-1, and M 19-1, were selected These were identified, by their biological characteristics, as Hansenuia ciferri, Pichia acaciae and Candida tropicalis, respectively. Their ferments were extracted with petroleum ether and fractionated into basic, neutral and acidic fractions. The major organoleptic properties of the fermented flavors were detected in the neutral fractions by the sensory test and the yields and threshold values of those fractions were determined and the organoleptic characteristics were described as well.

• Korean Journal of Microbiology
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• v.8 no.2
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• pp.77-84
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• 1970

The author attempted the taxonomical studies on yeasts in Takju mash. The samples used for the isolation of yeasts were collected from Takju breweries in Seoul. The yeasts obtained from Takju were identified as follows using the methods of Lodder et al. ; Saccaromyces cerevisiae group II, Saccharmyces cerevisiae group III, other group of Saccharomyces cerevisiae, Hansenula anomala and Pichia polymorpha. Saccharomyces cerevisiae II & III and other group Saccharomyces cerevisiae which were considered as wild yeasts have shown their major role in the fermentation process of Takju brewing. It seems that Hansenula anomala has much connection with the flavour of Takju. Other strains which are poor in their acoholic fermentation and lower in activity of acid production are not considered to be important in Takju brewing.

• Journal of Dairy Science and Biotechnology
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• v.36 no.1
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• pp.26-31
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• 2018

Tarak is a traditional Korean fermented milk product, which is prepared by the addition of rice wine to milk. The major microbial strains found in Tarak are Leuconostoc citreum, Lactobacillus plantarum, Lactococcus lactis, Saccharomyces cerevisiae, and Pichia kudriavzevii. The activity of lactic acid bacteria isolated from traditional Korean foods of Taraki against the carcinogenic bacteria Helicobacter pylori, Escherichia coli O157:H7, and Cronobacter sakazakii was characterized. Tarak extract significantly increased the proliferation of T-lymphocyte Jurkat (clone E6-1) cells. Tarak also inhibited the tyrosinase activity and melanin biosynthesis induced by an ${\alpha}$-melanocyte-stimulating hormone in pituitary intermediate lobe.