• 한국식품저장유통학회지
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• 제22권4호
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• pp.528-534
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• 2015

유청을 막걸리 제조시 용수로 사용하기 위해 효모에 따른 유당 분해능과 ethanol 생성능력을 측정하고, 유청 첨가 비율에 따른 막걸리를 제조하여 총산, pH, 환원당, ethanol 및 관능평가 등 품질특성을 확인한 결과는 다음과 같다. 유당 분해능은 K. marxianus KCCM 35455과 K. marxianus KCCM 50700이 가장 뛰어난 유당 분해능을 보였으며, ethanol 생성능력은 K. marxianus KCCM 50700 균주의 ethanol 함량이 가장 높은 것으로 나타났다. 따라서 유당분해능과 ethanol 생성능이 우수했던 K. marxianus KCCM 50700의 효모를 선정하여 유청 막걸리 제조 연구를 진행하였다. 유청 첨가비율에 따른 막걸리의 발효과정 중 총산은 K. marxianus KCCM 50700으로 담금한 시료구의 경우 S. cerevisiae로 담금한 막걸리의 산도보다 비교적 낮은 경향을 보였으며, pH는K. marxianus KCCM 50700로 담금한 시료구의 경우 S. cerevisiae로 담금한 막걸리의 pH보다 비교적 높은 경향을 보였다. 환원당 함량은S. cerevisiae 시료구에서는 유청 첨가비율이 높아짐에 따라 환원당 함량이 높아졌으며, K. marxianus KCCM 50700 시료구에서는 큰 함량차이가 나타내지 않았다. ethanol 함량 변화는K. marxianus KCCM 50700로 담금한 시료구가 S. cerevisiae로 담금한 시료구 보다 높게 나타났다. 관능평가는 향, 색, 맛 및 종합기호도면에서 K. marxianus KCCM 50700로 담금한 유청 100% 첨가 시료구가 높은 기호도를 보였다.

• KSBB Journal
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• 제30권3호
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• pp.125-131
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• 2015

Kluyveromyces marxianus is a well-known thermotolerant yeast. Although Saccharomyces cerevisiae is the most commonly used yeast species for ethanol production, the thermotolerant K. marxianus is more suitable for simultaneous saccharification and fermentation (SSF) processes. This is because enzymatic saccharification usually requires a higher temperature than that needed for the optimum growth of S. cerevisiae. In this study, we compared the fermentation patterns of S. cerevisiae and K. marxianus under various temperatures of fermentation. The results show that at a fermentation temperature of $45^{\circ}C$, K. marxianus exhibited more than two fold higher growth rate and ethanol production rate in comparison to S. cerevisiae. For SSF using starch or corn stover as the sole carbon source by K. marxianus, the high temperature ($45^{\circ}C$) fermentations showed higher enzymatic activities and ethanol production compared to SSF at $30^{\circ}C$. These results demonstrate the potential of the thermotolerant yeast K. marxianus for SSF in the industrial production of biofuels.

• 한국식품과학회지
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• 제30권1호
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• pp.161-167
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• 1998

치즈 제조시 생기는 부산물인 유청을 이용하여 알코올 발효 음료를 만들기 위해 유당을 이용하는 효모인 K. marxianus KCCM 32422와 유당을 이용하지 않는 S. cerevisiae KCCM 12028의 2종류의 효모 균주와 7균주의 젖산균을 혼합 배양하여 알코올 생성량 $CO_2\;gas$의 생산량, 적정산도의 변화, 그리고 관능적 특성을 조사하였다. K. marxianus KCCM 32422와 Lb. bulgaricus Lb-12를 혼합배양시에는 4일째 알코올 함량이 2.8%였으며, S. cerevisiae KCCM 12028과 Lb.bulgaricus Lb-12를 혼합배양시에는 4일째 알코올 함량이 0.2%였다. 효모를 첨가하는 최적시간은 K. marxianus KCCM 32422는 젖산균을 접종후 24시간에, S. cerevisiae KCCM 12028은 젖산균 접종후 16시간에 하는 것이 효과적이었다. K. marxianus KCCM 32422와 7균주의 젖산균을 혼합배양시에는 K. marxianus KCCM 32422와 L. lacis KCCM 32406가 배양 96시간에 알코올 2.3%, $CO_2\;gas$는 1.9%로 다른 젖산균에 비하여 알코올과 $CO_2\;gas$의 높은 생산량을 나타내었다. 배양 온도는 $37^{\circ}C$에서 하는 경우가 $20^{\circ}C,\;30^{\circ}C,\;42^{\circ}C$에서 발효시키는 것보다 높은 알코올과 $CO_2\;gas$생산량을 나타내었다. 전반적인 기호도는 L. lacits KCCM 32406가 신맛은 조금 강하고 쓴맛은 전혀 없으며 알코올 맛은 조금강하여 가장 적당하다고 평가되었다.

• 한국미생물·생명공학회지
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• 제45권1호
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• pp.57-62
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• 2017

최근 모균주인 K. marxianus ATCC 36907 보다 xylose reductase의 활성이 증대된 돌연변이 K. marxianus 36907-FMEL1 균주를 개발하였다. 본 연구에서는 효율적인 xylitol의 생산을 위해 발효기를 이용하여 교반속도에 따른 효과를 확인하였다. $30^{\circ}C$ 조건에서 발효를 진행한 결과 K. marxianus 36907-FMEL1 균주는 400 rpm의 교반속도에서 가장 높은 수율 (0.57 g/g)과 생산성($0.64g{\cdot}l^{-1}{\cdot}h^{-1}$)을 확인할 수 있었다. 흥미롭게도 온도 조건을 $40^{\circ}C$로 증가하여 발효를 진행한 결과 agitation 조건 최적화를 통해 수율과 생산성이 각각 21% (0.64 g/g)와 58% ($0.90g{\cdot}l^{-1}{\cdot}h^{-1}$) 증가하였다.

• Food Science and Biotechnology
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• 제16권1호
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• pp.133-137
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• 2007

The Strain TFM-7, Which has an antitumor effect, was isolated from Kefir and identified based on analysis using the API 50 CHL kit and 265 rDNA sequencing. Strain TFM-7 was confirmed to belong to the genus Kluyveromyces. Analysis of the 265 rDNA nucleotide sequences found strain TFM-7 to be related to Kluyveromyces marxianus. NRRL Y-828IT. K. marxianus. TFM-7 was cultured with potato dektrose broth medium at $27^{\circ}C$ for 72 hr, and its inhibition effects on the proliferation of seven tumor cell lines and a normal cell line were assessed using the MTT assay. The antitumor effects and growth characteristics of K. marxianus TFM-7 were investigated during a culture period of 7 days. By the $3^{rd}\;day$, K. marxianus TFM-7 showed a dry cell weight 2.39 g/L, a pH of 4.39, an ethanol content of 0.89%, and an inhibition effect on the proliferation of seven tumor cell lines above 50%, except for A-549 tumor cell line. K. marxianus TFM-7 was the most effective at inhibiting the growth of Hep-2 cell line among all tumor cell lines tested. Growth inhibition of a normal cell line, NIH/3T3, was less than 35%, suggesting a decreased level of cytotoxicity toward normal cells. These results indicate that K. marxianus TFM-7 may have used as a yeast strain with antitumor activity.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.447-450
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• 2005

Aspergillus niger inuE gene and Kluyveromyces marxianus INUI gene coding for exoinulinase were expressed in Saccharomyces cerevisiae under the control of K. marxianus INUI promoter. Recombinant S. cerevisiae expressing K. marxianus exoinulinase produced maximum 85 U/ml into culture medium, which was 9- to 14-fold higher than the activity produced by any other strain reported so far. In addition, K. marxianus INUI promoter produced 20- fold higher activity than S. cerevisiae glyceraldehydes phosphate dehydrogenase (GPD) promoter in S. cerevisiae.

• KSBB Journal
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• 제25권6호
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• pp.565-571
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• 2010

To develop thermostable ethanol fermentative yeast strain for lignocellulosic simultaneous saccharification and fermentation, high ethanol producing yeast, Saccharomyces cerevisiae CHY1012 and thermostable yeast, Kluyveromyces marxianus CHY1703 were fused by protoplast fusion. The thermostable fusant, CHY1612 was identified as a Kluyveromyces marxianus by phenotypic and physiological characteristics, as well as molecular analysis based on the D1/D2 domains of the large subunit (26S) rDNA gene and the internally transcribed spacer (ITS) 1 + 2 regions. For lignocellulosic ethanol production, AFEX pretreated barley straw at $150^{\circ}C$ for 90 min was used in a simultaneous saccharification and fermentation (SSF) process using thermotolerant CHY1612. The SSF from 16% pretreated barley straw at $43^{\circ}C$ gave a saccharification ratio of 90.5%, a final ethanol concentration of 38.5 g/L, and a theoretical yield of 91.2%. These results show that K. marxianus CHY1612 has potential for lignocellulosic ethanol production through simultaneous saccharification and fermentation with further development of process.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2001년도 정기총회 특별강연 및 춘계학술연구발표회(2)
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• pp.121-125
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• 2001

For the probiotic feed production, aerobic liquid fermentation of pulverized food wastes was attempted with a yeast Kluyveromyces marxianus. After grinding finely, optimal fermentation conditions of the substrate was investigated by shaking culture. The most active growth of the yeast was shown at solid content of 10%. The proper addition of urea(0.5g/l), o-phosphate(0.4g/l), molasses(4g/l), and yeast extract (1g/1) increased cell growth rate and viable cell count. For optimizing, the nutrients were all added to substrate and fermentation was carried in 2 litre jar fermenter. For the stimulation of hydrolyzing enzyme excretion, mixed culture with Aspersillus oryzae was also conducted. In 12 hours of fermentation, viable cell count of the yeast Kluyveromyces marxianus amounted to the number of 1.4 $\times$10$^{10}$ /1 in the culture medium.

• Journal of Microbiology and Biotechnology
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• 제30권12호
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• pp.1944-1949
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• 2020

Mutant sugar transporter ScGAL2-N376F was overexpressed in Kluyveromyces marxianus for efficient utilization of xylose, which is one of the main components of cellulosic biomass. K. marxianus ScGal2_N376F, the ScGAL2-N376F-overexpressing strain, exhibited 47.04 g/l of xylose consumption and 26.55 g/l of xylitol production, as compared to the parental strain (24.68 g/l and 7.03 g/l, respectively) when xylose was used as the sole carbon source. When a mixture of glucose and xylose was used as the carbon source, xylose consumption and xylitol production rates were improved by 195% and 360%, respectively, by K. marxianus ScGal2_N376F. Moreover, the glucose consumption rate was improved by 27% as compared to that in the parental strain. Overexpression of both wild-type ScGAL2 and mutant ScGAL2-N376F showed 48% and 52% enhanced sugar consumption and ethanol production rates, respectively, when a mixture of glucose and galactose was used as the carbon source, which is the main component of marine biomass. As shown in this study, ScGAL2-N376F overexpression can be applied for the efficient production of biofuels or biochemicals from cellulosic or marine biomass.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.346-351
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• 1995

To produce ethanol from Jerusalem artichoke powder efficiently, Kluyveromyces marxianus F043 cells were encapsulated in 2% sodium alginate and were cultured in a countinuous reactor to investigate the fermentation properties. Immobilized K. marxianus F043 cells were activated for 48 hours in a fermentor for continuous ethanol production. The culture in a CSTR using a Jerusalem artichoke substrate treated with 2% cellulase showed a decrease in ethanol concentration and an increase in residual saccharide concentration with a increasing dilution rate. Optimum conditions for high ethanol productivity and low residual saccharide output were clarified to be given at a dilution rate of 0.2 h$^{-1}$ and a Jerusalem artichoke medium concentration of 75 g/l. Ethanol productivity of 3.1 g/l-h and saccharide utilization of 62.6% were obtained under the optimum condition. When the fermentation was performed for 3 weeks under these conditions, the effluent medium showed stable ethanol concentrations of 16.3 - 17.9 g/l and viable cells of 6.60-7.16 log cells/ml without contamination. Trace amounts of methyl, n-propyl, iso-butyl, isoamyl alcohols besides ethanol were detected.