• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.669-674
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• 1997

This study was attempted to express human lactoferrin gene that has importance as a functional additive in food industry. Lactoferrin has distinctive antibacterial properties. Also, a number of phy-siological roles have been postulated for the lactoferrin in the modulation of immune and inflamatory responses and as a growth factor. Since it did not show feasible growth inhibition by antimicrobial test against HLF, Pichia pastoris was selected the best lactoferrin expression host. HLF expression plasmid pHIL-SI was integrated into the genomic DNA of P. pastoris GSl15. The integration was confirmed not only with 2.4Kb fragment of HLF gene by PCR(polymerase chain reaction) product, but also with same size of specific signal by southern blotting. Among the various pichica transformants, the JY-1 cell showed a positive response for the expression of HLF by the immunoblotting anaysis. The recombinant HLF protein was started to be secreated at 48hr of culture and reached at the highest secreation level at 96hr.

• Journal of Animal Science and Technology
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• v.44 no.3
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• pp.289-296
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• 2002

A broiler experiment was conducted to investigate the effect of supplementing yeast culture (Saccharomyces cerevisiae, Pichia pastoris) on the growth performance, small intestinal microflora and immune response in broiler chickens. One thousand hatched broiler chickens(Ross$^{(R)}$) were assigned to 6 treatments: control (basal diet), CTC; chlorotetracycline 100ppm, YC-SC; yeast culture(Saccharomyces cerevisiae) 0.3%, YC-PP; yeast culture(Pichia pastoris) 0.3%, RPPC-0.1; refined Pichia pastoris culture 0.1%, RPPC-0.3; refined Pichia pastoris culture 0.3%. There were no significant differences in growth, feed intake, feed efficiency and mortality among the treatments. However, chickens fed diets with yeast cultures showed numerically higher weight gain than those fed the control diets. Supplementation of yeast cultures and CTC improved feed efficiency and decreased mortality compared to control. Nutrient digestibilities were not affected by the dietary treatments. Total number of Lactobacilli in small intestine was higher while that of Cl. perfringens was lower with yeast culture treatments than control. Small intestine E. coli population of RPPC-0.3 treatment was significantly lower than that of the control. The serum IgG concentration tended to be higher in broilers fed yeast cultures than those fed the control and CTC diet. In conclusion, the supplementation of yeast culture products showed, although not significant but, numerical advantages in productivity and profile of microbial flora and serum IgG compared to the control and CTC supplementation.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.219-224
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• 2014

In order to develop a new anti-diabetic ${\alpha}$-glucosidase inhibitor, we compared the ${\alpha}$-glucosidase inhibitory activity of the cell-free extracts of 48 strains of yeasts isolated from Korean fermented foods, and found that Pichia burtonii Y257-7 exhibited the highest ${\alpha}$-glucosidase inhibitory activity of 55.6%. The ${\alpha}$-glucosidase inhibitor was maximally produced when Pichia burtonii Y257-7 was cultured in LB broth (initial pH of 6.0) at $28^{\circ}C$ for 24 h. The ${\alpha}$-glucosidase inhibitor, partially purified by Sephadex G-50 gel permeation chromatography and systematic solvents extraction, revealed potent hypoglycemic effects in normal rats and streptozotocin-induced diabetic rats after the oral administration of starch.

• Proceedings of the Korean Nutrition Society Conference
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• 2003.10a
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• pp.152-152
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• 2003

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.435-443
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• 1989

The regulation of the synthesis of alcohol-oxidase(E. C. 1. 1. 3. 13) was investigated in the methanol-utilizing yeasts during growth on different carbon sources. For this experiment, Pichia pastoris CBS 2612 and Pichia pastoris CBM 10 were cultured in mineral salt medium by changing its carbon sources. The production of alcohol-oxidase was varied by the carbon sources. For example, alcohol-oxidase was undetectable in all strains submitted to the test in the medium with glucose, but its production was rapidely increased when the carbon source was changed from glucose to methanol after 48hrs of incubation. Moreover, this enzyme was not synthesized during growth on the primary aliphatic alcohols alone(ethanol, propanol, butanol or pentanol) or on the mixed substrates(0.5% methanol+0.5% primary aliphatic alcohols). When cells were grown on the various carbon sources(glucose, xylose, lactose, glycerol, galactose, saccharose, sorbose, lactic acid or acetic acid), The alcohol-oxidase activity was detected a very little amounts. These carbon sources together with methnol yieled far better synthesis of alcohol-oxidase than in case of carbon sources alone. Especially, the alcohol-oxidase activity of the cells grown on sorbose, lactose or lactic acid together with methanol was far better or similar than that of cells grown on methanol alone. The apparent Km values for the methanol of Pichia pastoris CBS 2612 and Pichia pastoris CBM 10 enzymes were 1.92 and 210 mM, respectively. It is also active towards alcohols of shorter alkyl-chain length than $C_7$, insaturated alcohols(allylalcohol, crotyl-alcohol) and secondary alcohols (iso-amylacohol, iso-butylalcohol). The affinity of alcohol-oxidase for this alcohols decreased with the increasing length of the alkyl-chain.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1135-1142
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• 2003

The purification and characteristics of the biosynthesis enzyme of vitamin C from microorganisms related with kimchi fermentation were investigated to define vitamin C biosynthetic pathways in yeast. A yeast strain (Pichia onychis 16-4) which synthesizes vitamin C with galacturonic acid as substrate at high rate was isolated from kimchi. The enzyme $L-galactono-{\gamma}-lactone$ oxidase isolated from the yeast was purified and characterized. The specific activity of the crude enzyme was 7.26 unit/mg protein, which increased to 4,698 unit/mg protein with a chromatography of Sephacryl S-200HR; indicating a 647.1-fold level of purification. The molecular weights of the dissociated enzymes were estimated to be 31,000, 39,000, and 50,000 KD. Among the substrates tested, $L-galactono-{\gamma}-lactone$ was the most effective. The enzyme showed optimum activity ah pH 7.8 and 35c. The purified enzyme uses $O_2$ as the electron acceptor for oxidation of $L-galactono-{\gamma}-lactone$.

• KSBB Journal
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• v.25 no.3
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• pp.283-288
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• 2010

We investigated the feasibility of bioethanol production from hydrolysate of brown seaweed Sargassum sagamianum. Prior to bioethanol production using yeasts, six yeast strains were compared and the best ones in terms of the ethanol production levels were selected. Pichia stipitis ATCC 7126, Pichia stipitis ATCC 58784, and Pichia stipitis ATCC 58376 were superior to others in terms of ethanol production. These yeast strains were used for producing bioethanol by the shaking bottle culture and the fermentor culture. Out of approximately 30 g/L reducing sugar, about 3~6 g/L and 4~7 g/L bioethanol were produced in the bottle culture and the fermentor one, respectively. Furthermore, it was observed that around 12~28 g-bioethanol was produced from 1 kilogram of Sargassum sagamianum. Compared with those previously published, these data were almost three to eight times higher in value.

• Journal of the Korean Wood Science and Technology
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• v.46 no.4
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• pp.415-422
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• 2018

Terpenoids have a wide range of biological functions and have extensive applications in the pharmaceutical, cosmetic, and flavoring industry. The white-rot fungus, Polyporus brumalis, is able to synthesize terpenoids via terpene synthase, which catalyzes an important step that forms a large variety of sesquiterpene products from farnesyl pyrophosphate (FPP). To improve the production of sesquiterpenes, the terpene synthase gene was isolated from Polyporus brumalis and was heterologously transformed into a Pichia pastoris strain. The open reading frame of the isolated gene (approximately 1.2 kb) was inserted into Pichia pastoris to obtain a recombinant enzyme. Five transformants were obtained and the expression of terpene synthase was analyzed at the transcript level by reverse transcription PCR (polymerase chain reaction) and at the protein level by SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis). Expression of the terpene synthase gene product was elevated in the transformants and as expected the molecular weight of the protein was approximately 45 kDa. These recombinant enzymes have potential practical applications and future studies should focus on their functional characterization.

• Journal of Microbiology
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• v.38 no.2
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• pp.88-92
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• 2000

A human ribosomal protein S3 (rpS3), which also functions as a DNA repair enzyme(UV endonuclease III), was expressed in a methylotrophic yeast, Pichia pastoris, and biochemically characterized. UV endonuclease activity was preiously characterized, and this activity of mammalian rpS3 was found to be non-specfic upon purification and storage. Under the Pichia expression system, the subcloned cDNA of the human rpS3 gene revealed a peptide of 42 kDa by SDS-PAGE and Western blot. The secreted form of human rpS3 rendered no endonuclease activity while the intracellular form showed UV specific endonuclease activity by the nick circle assay.

• Journal of Dairy Science and Biotechnology
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• v.39 no.3
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• pp.87-93
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• 2021

This study analyzed and compared growth characteristics under large-scale fermentation at 35℃ of three microorganisms with the ability to reduce odor-producing substances in livestock. The three microorganisms (Bacillus subtilis FWC1, Bacillus amyloliquefaciens NAAS1, and Pichia farinosa NAAS2) evaluated in this study have been proven effective in reducing odor-inducing substances. Bacillus subtilis FWC1 exhibited the highest viable cell count when using 2% maltodextrin as carbon source, 0.05% soy-peptone as nitrogen source, and 0.3% yeast extract. The optimum media composition for B. amyloliquefaciens NAAS1 was 1.2% modified-starch with 0.8% yeast extract. The spore formation rate in the mass production of the Bacillus strains was over 90%, indicating that optimal growth medium compositions have been identified. In the case of P. farinosa NAAS2, our optimized growth medium [2% (w/v) glucose and 1% (w/v) yeast extract] improved biomass production.