• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.23-23
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• 2014

There are many yeast strains have been discovered for industrial usage in global scale. In the point of view for the alcoholic fermentation performance and producing alcoholic beverage products, recently many countries have known about the importance of microorganisms as a valuable resource. Discovered with well performed yeasts have potential industrial application in diverse ways such as foods, beverages, cosmetics, pharmaceutical functions, and so on. In Korea, the yeast research has not been sufficiently performed especially for distilled spirits industry. As a result, not so little manufacturers use exotic yeasts from overseas even included the expensive royalties. Besides of those, to produce distilled spirits, many manufacturers do not use specialized yeast for distilled spirits. Distiller's characterized yeasts such as whisky, brandy, vodka, Japanese shochu and awamori, are all well-known industrialized. For decades, the distillers, except us, have selected, developed, and practised yeasts in accordance with distilled spirits characters. This study is about selection and industrial application of yeasts for the Korean pot distilled spirits. Finally 7 yeast strains were selected among over 1,000 yeasts from the traditional Nuruks, through the essential related tests based on brewing and distilling science. The selected yeasts show the appropriate characteristics of distilled spirits. The result of this study could help our distilled spirits industry be activated and stand independent from the exotic microbes.

• Korean Journal of Microbiology
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• v.8 no.4
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• pp.141-150
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• 1970

As a part of taxonomical and ecological studies on the yeasts in marine environments, several kinds of yeasts were isolated from Zostera marina several invertebrates (penaeus, Meretrix and Neptunus) and surface sea water, which are collected at the two established sites of estuarine areas ; Dolsan isaland in Youchun district and Baiksu-ri in Youngkwang district. The obtained results can be summarized as follows. 1. Ascosporgenous Yeasts. Hansenula sp I and Hansenula sp II were isolated from Zotera marina and Hanse nular sp I from penaeus. 2. Asporogenous Yeasts. Trichoporon fermentans, Torulopsis, ernobii and Toruopsis dattia were isolated from Zostera marina, Candida krusei from Meretrix and Neptunus, Torulopsis pinus from surface sea waters, and Phodotorula aurantiaca from Penaeus. 3. More notable isolations of several species from Zostera marina than the other sources could be assumed as related to the higher sugar concentration of this plant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.2
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• pp.232-238
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• 1998

To developed natural food preservatives, ethanol and water extracts were prepared from the defatted camellia(Camellia japonica L.) seeds. Antimicrobial activities were examined against 14 microorganisms which were food borne pathogens and/or food poisoning microorganisms and food-related bacteria and yeasts. Ethanol extract showed antimicrobial activities against several microorganisms tested, but not on lactic acid bactria. Especially, minimum inhibitory concentrations(MIC) for yeasts were as low as 1mg/ml. Water extract exhibited antimicrobial activities for the yeasts tested, but almost bacteria were not observed. The ethanol extract was fractionated in the order of hexane, chloroform, ethylaetate and butanol fractions to test antimicrobial activity. The strongest activity for the tested yeasts were found in the butanol fractions, but bacteria were chloroform fraction. Hansenula anomala treated with ethanol were observed by scanning electron micrograph, and the results exhibited morphological changes, including the irregularly contracted cell surface and expanded ellipsoidal shape.

• Journal of the Korean Society of Food Culture
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• v.15 no.4
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• pp.233-239
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• 2000

In order to optimize the quality of pine sprout tea, its chemical properties were analyzed and the yeasts associated with the quality of pine sprout tea during the storage were isolated and identified. In proximate composition moisture content was 20.13%, but other components except sugar were relatively low. Sugars such as glucose(30.15%), fructose(19.57%), and sucrose(9.27%) were major sugars which contained up to 76.73%. Total vitamin C and soluble tannin contents were 11.31 mg% and 68.31 mg%, respectively. Thirteen kinds of free amino acids were detected, but they were contained only in trace. In fatty acid composition 64.69% of fatty aids composed mainly of saturated fatty acids and major fatty acids were oleic acid, palmitic acid, and tricosaenoic acid. Among 8 mineral elements detected, calcium content was highest with 79.00 mg% and followed by potassium(45.16 mg%) and magnesium(8.93 mg%). The sweetness of pine sprout tea was gradually decreased from $70^{\circ}\;Brix\;to\;63^{\circ}\;Brix$ and 3.2% of ethanol at the initial concentration was increased to 6.0% during the storage of 40 days. The yeasts associated with the quality and alcohol formation of pine sprout tea during the storage were identified by Biolog MicrostationlTM system, as Zygosaccharomyces rouxii, Kluyveromyces lodderae, Kluyveromyces wickerhamii, and Pichia fluxuum.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.444-447
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• 2000

The microbial changes during the fermentation of salted and fermented shrimp at different salt levels $(3{\sim}30%)$ were investigated to elucidate the effect of salt on the microflora of the fermented shrimp. During 22 weeks of fermentation, the numbers of total bacteria and yeasts of the fermented shrimp with 3, 8, 30% salt generally decreased with fermentation time, while those in the fermented shrimp of 18% salt increased. Halophilic bacteria were found only in the late stage of the fermentation at 18% salt. The greatest number of the halophilic yeasts was observed also at 18% salt level. The results indicated that 18% salt provided the most favorable environment for the microorganisms related to the shrimp fermentation.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.253-257
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• 1991

Cellular carbohydrates were hydrolysed and analyzed in the strains of Leucosporidium scottii and its related species of basidiomycetous yeasts by HPLC methods without any derivatization. Xylose was detected from the hydrolyses of the cellular carbohydrates of L. lari-marini, but not from those of three strains of L. antarcticum, L. fellii, and Rhodosporidium fluviales. not also from those of six strains of L. scottii contrary to other data reported. L. antarcticum and L. lari-marini were considered to be placed on the different genus of Cystofilobasidium or Mrakia, as based on the numerical analyses.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.7-12
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• 2010

The biochemical study of sugar uptake in yeasts started five decades ago and led to the early production of abundant kinetic and mechanistic data. However, the first accurate overview of the underlying sugar transporter genes was obtained relatively late, due mainly to the genetic complexity of hexose uptake in the model yeast, Saccharomyces cerevisiae. The genomic era generated in turn a massive amount of information, allowing the identification of a multitude of putative sugar transporter and sensor-encoding genes in yeast genomes, many of which are phylogenetically related. This review aims to briefly summarize our current knowledges on the biochemical and molecular features of the transporters of pentoses in yeasts, when possible establishing links between previous kinetic studies and genomic data currently available. Emphasis is given to recent developments concerning the identification of D-xylose transporter genes, which are thought to be key players in the optimization of S. cerevisiae for bioethanol production from lignocellulose hydrolysates.

• KSBB Journal
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• v.19 no.5
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• pp.352-357
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• 2004

Human ferritin H- and L-chain genes (hfH and hfL) were cloned into the yeast shuttle vector YEp352 containing the GAL1 (galactokinase) and GAL10 (epimerase) divergent promoters and the vectors constructed were used to transform Saccharomyces cerevisiae 2805. SDS-PAGE displayed expression of the introduced hfH and hfL in both recombinant strains of Y1H10L and Y1L10H. The ferritin subunits, that represented ca. $22\%$ and $15\%$ of the soluble proteins in Y1H10L and Y1L10H, were spontaneously assembled into active ferritin heteropolymers. The H subunit content of the purified recombinant human ferritin heteropolymers was proven to reflect the relative expression yield of the subunits. When the cells of 2d culture were incubated with 14.3 mM Fe(2), the cellular iron concentration of Y1H10L and Y1L10H was 1.7 and 2.0 times, respectively, that of the control strain. It is assumed that increase in the iron uptake of the recombinant yeasts is closely related to ferritin expression and H subunit content.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.293-297
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• 1997

To develope natural food preservatives of pine needle (Pinus densiflora Seib et Zucc.) extract, pine needle sap, ethanol and ether extracts were prepared for investigation of antimicrobial activities against food-related bacteria and yeasts. All extracts exhibited growth inhibiting activities for most of microorganisms tested. However, in general, growth inhibiting activities were higher in ethanol extract than in sap or ether extract. Minimum inhibitory concentrations (MIC) of ethanol extract for Lactobacillus casei, Pseudomonas aeruginosa or Escherchia coli were as low as 0.1 mg/ml, whereas MIC of sap or ether extract for most bacteria and yeasts were 0.25-0.8mg/ml, indicating that the ethanol extract showed the antimicrobial activity by 2.5 $\sim$8 times higher than the sap and ether extract. The antimicrobial activity of the ethanol extract was reduced by heating or alkali treatment. Moreover, growth of Pseudomonas aeruginosa was completely inhibited within 24 hours by the addition of at least 50ppm of ethanol extract. These findings suggest that pine needle, specially the ethanol extrat may play a role for natural food preservatives.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.791-797
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• 1999

This study was conducted in order to evaluate nutritive values of yeasts (Kluyveromyces fragilis and Candida utilis) according to growth stages (early log phase, log phase, stationary phase and death phase) and chemical treatment of their cell wall, Proximate, amino acids, fatty acids and nucleotides composition of the yeast samples was determined. Crude protein content was high in K. fragilis ($48\~59\%$) compared to C. utilis ($26\~43\%$). Crude lipid and fiber contents of the yeasts were below than $1.6\%$ and $3.3\%$, respectively. Conposition of aspartic acid, glycine, proline, leucine, Iysine and valine of K. fragilis were higher than those of C. utilis, and glutamic acid and arginine of C. utilis were higher than those of K. fragilis. Proximate and amino acids composition was not siginificantly influenced by growth stage of the yeasts. Major fatty acids of the yeasts in all growth stages were $C_{10-18}$. $C_{16-18}$ contents were relatively high in the early log or log phase and $C_{10-12}$ contents were relatively high in the stationary or death phase. However, n-3 highly unasturated fatty acids (C$\ge$20) in the all growth stages were not observed. This result indicated that these yeast strains could not be adequate as a dietary lipid source for marine fish. Composition of nucleotides and their related compounds (ATP ADP AMP, IMP and inosine) in the early log phase yeasts were lower than those in the log, stationary and death phase yeasts.