• 한국미생물·생명공학회지
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• 제50권3호
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• pp.404-413
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• 2022

The process of manufacturing craft beer involves a wide variety of spontaneous microorganisms, acting in different stages of the brewing process, that contribute to the distinctive characteristics of each style. The objective of this work was to compare the structure of microbial communities associated with two different craft beer styles (Doppelbock and Märzen lagers), at a late maturation stage, and to identify discriminative, or style-specific taxa. Bacterial and fungal microbial communities were analyzed by Illumina sequencing of 16S rRNA gene of prokaryotes and the ITS 2 spacer of fungi (eukaryotes). Fungal communities in maturating beer were dominated by the yeast Dekkera, and by lactic acid (Lactobacillus and Pediococcus) and acetic acid (Acetobacter) bacteria. The Doppelbock barrels presented more rich and diverse fungal communities. The Märzen barrels were more variable in terms of structure and composition of fungal and bacterial communities, with occurrence of exclusive taxa of fungi (Aspergillus sp.) and bacteria (L. kimchicus). Minority bacterial taxa, differently represented in the microbiome of each barrel, may underlie the variability between barrels and ultimately, the distinctive traits of each style. The composition of the microbial communities indicates that in addition to differences related to upstream stages of the brewing process, the contact with the wood barrels may contribute to the definition of style-specific microbiological traits.

• 한국식품영양학회지
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• 제13권2호
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• pp.171-175
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• 2000

Microbial proteases have certain unique characteristics, and are now widely used in food, leather, detergent, and pharmaceutical industries. Thermophilic Actinomyces producing the protease was isolated from soil in Wonju city. This strain was able to grow and produce protease at the culture temperature of 50$^{\circ}C$. The maximum protease production was obtained when 0.5% soluble starch and 0.4% yeast extract were used as carbon and nitrogen source, respectively. The other culture condition for the maximal productivity of the protease was 0.1% K2HPO4, and 0.05% CaCl2 at initial pH 8.0 for 48 hours.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.133-137
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• 2004

Tetrachloroethylene(PCE) dechlorination was investigated in an anaerobic enrichment culture from landfill soil. Anaerobic PCE dechlorinating microorganisms could convert 150mg/L of PCE via trichloroethylene(TCE) to cir-1,2-dichloroethylene(CDCE) within 2 days at the optimum temperature of 30 to 35$^{\circ}C$. The enrichment culture could dechlorinate TCE but did not degrade other chlorinated aliphatic compounds, such as cDCE, trans-1,2-dichloroethylene, 1,1-dichloroethylene, 1,1-dichloroethane, 1,2-dichloro- ethane, and 1,1,1-trichloroethane during 5 days incubation. Several isolates from the enrichment culture did not show dechlorinating activity of PCE. Microbial analysis of the dechlorinating enrichment culture by using Polymerase chain reaction-Denaturing gradient gel electrophoresis (PCR-DGGE) method showed that at least three microorganisms were related to the anaerobic PCE dechlorination in the enrichment

• Journal of Animal Science and Technology
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• 제45권6호
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• pp.987-996
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• 2003

본 실험은 수준별 산삼 배양액에 의한 반추위 내 미생물 발효성상에 미치는 영향에 대하여 조사하기 위해 실시되었다. 산삼 배양액의 수준에 따른 반추위 내 발효성상에 미치는 영향은 WGM을 3% 첨가한 처리구가 대조구 및 다른 WGM 수준 첨가 처리구에 비하여 미생물 단백질 합성량이 가장 높게 나타났다. 산삼 배양액 내에 존재하는 saponin의 영향으로 배양 초기 NH3-N 농도의 수준이 WGM를 첨가한 처리구가 대조구에 비해 낮은 경향(P〈0.05)을 보였으나, 미생물단백질 합성량은 WGM 처리구에서 6시간 이후 급격히 증가(P〈0.05)하는 경향을 나타내었다. 따라서 용해도가 높거나 급여 초기 사료의 이용율이 저하되는 급여 체계에서 산삼 배양액을 첨가는 초기 반추위 미생물의 이용율을 조절할 수 있을 것으로 사료된다. 반추위 내 프로토조아의 수는 WGM 처리구에서 전반적으로 배양 9시간까지 낮아졌고, 3% 처리구에서 가장 낮았는데(P〈0.05), 프로토조아 제거효과에 의해 반추위 미생물합성량 증진시키는 효과를 나타내었다. NDF와 ADF 소화율은 대조구와 모든 처리구에서 배양시간 경과에 따라 높아졌고, NDF 소화율은 대조구와 WGM 3% 처리구에서 그리고 ADF 소화율은 처리구별 차이가 없었다. Total VFA 생성량은 처리구가 대조구에 비해 낮았고, 배양 12시간부터는 5% 처리구에서 차이가 없게 나타났다. 따라서 용해도가 높거나 급여 초기 사료의 이용률이 저하되는 급여 체계에서 산삼 배양액을 첨가는 초기 반추위 미생물의 사료 이용률 증진과 프로토조아 제거효과에 의해 반추위 미생물합성량 증진에 도움이 될 수 있을 것이다.

• 한국환경농학회지
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• 제29권3호
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• pp.293-299
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• 2010

본 연구의 목적은 Bt 배추의 토양미생물 군집에 미치는 영향을 조사하기 위한 것이다. 토양미생물 조사에 앞서 토양 화학성분을 분석한 결과, Bt 배추와 일반품종 배추 근권토양간 화학성분의 유의성 있는 차이는 없는 것으로 조사되었다. 생육 최대 성숙기의 토양미생물 군집밀도를 조사했을 때 Bt 배추 근권토양의 미생물 군집밀도 범위가 일반 배추 근권토양의 미생물 군집밀도 범위내에 속하는 것으로 나타났다. 월별 DGGE 분석결과 일반품종 배추 근권토양 미생물 군집에 비해 Bt 배추 근권토양 미생물 군집의 변이는 없었다. 형질전환 벡터 유래 유전자부위를 이용하여 유전자의 수평이동성을 조사했을 때 Bt 근권토양 유래 DNA에서는 벡터 유래 유전자가 검출되지 않았다.

• 환경생물
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• 제22권
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• pp.38-46
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• 2004

다환 방향족 탄화수소(PAHs)에 의한 오염이 미생물군집구조에 미치는 영향을 파악하기 위하여 연안에 가까운 광양만 퇴적토를 대상으로 하여 2000년 3월과 8월 2회에 걸쳐 PAHs 오염도와 말단제한절편 다형성 (T-RFLP)분석방법을 이용하여 미생물 군집구조를 조사하였다. T-RFLP방법으로 조사한 미생물 군집은 계절에 따라 군집이 구분되었으며 월내천입구에 위치한 정점 1에서 3월에 다른 정점과 다른 독특한 군집구조를 형성하였다. 또한 상대적으로 PAHs 오염도가 높은 정점들에서 미생물 다양성도 높은 것으로 나타났다. PAHs 농후배양시료에서의 미생물군집구조 변화와 비교해 볼 때 조사대상지역 퇴적토의 미생물 군집구조는 PAHs의 오염에 부분적으로는 영향을 받지만 군집구조를 결정하는 주된 요인은 온도, 입도, 유기물 함량 등과 같은 환경요인인 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.892-896
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• 2003

High-level expression of the lipase B26 gene from Bacillus pumilus was achieved using Bacillus subtilis Chungkookjang isolated from the Korean traditional fermented bean paste, Chungkookjang. For the secretory production of recombinant lipase B26 in a Bacillus host system, pLipB26 was constructed by ligating the lipase B26 gene into the recently designed Escherichia coli-Bacillus shuttle vector, pLipSM, and that was then transformed into B. subtilis Chungkookjang. Among the various vector, medium, and host combinations, B. subtilis Chungkookjang harboring the pLipB26 exhibited the highest lipase activity in PY medium, and B. subtilis Chungkookjang secreted two times more enzymes than B. subtilis DB 104 under the same condition. When B. subtilis Chungkookjang harboring the pLipB26 was cultured in a 5-1 jar-fermentor containing 21 of a PY medium, the maximum lipase activity (140 U/ml) and production yield (0.68 g/l) were obtained during the late exponential phase from a cell-free culture broth. Although B. subtilis Chungkookjang also secreted extracellular proteases at the late exponential phase, these results suggested the potential of B. subtilis Chungkookjang as a host for the secretory production of foreign proteins.

• 한국미생물·생명공학회지
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• 제27권4호
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• pp.311-319
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• 1999

Leaves of Aloe vera Linne and bloods of domestic animal were composted in a soild state fermentation reactor (SSFR) by using microbial additive including a bulking and moisture controlling agent. From solid-culture of microbial additive, 10 species of bacteria and 10 species of fungi were isolated and, their enzyme activities including amylase, carboxy methyl cellulase CMCase, lipase and protease were detected. Optimum fermentation conditions of Aloe leaves and domestic animal bloods in SSFR were obtained from the studies of response surface analysis employing microbial additive content, initial moisture content, and fermentation temperature as the independent variables. The optimum conditions for SSFR using Aloe leaves were obtained at 9.45$\pm$73%(w/w) of microbial additives, 62.73$\pm$4.54%(w/w) of initial moisture content and 55.32$\pm$3.14$^{\circ}C$ of fermentation temperature while those for SSFR using domestic animal bloods were obtained at 10.25$\pm$2.04%, 58.68$\pm$4.97% and 57.85$\pm$5.$65^{\circ}C$, respectively. Composting process in SSFR was initially proceeded through fermentation and solid materials were decomposed within 24 hours by maintaining higher moisture level, and maturing and drying steps are followed later. After the fermentation step, the concentrations of solid phase inorganic components were increased while that of organic components were decreased. Also, concentrations of total organic carbon(TOC), peptides, amino acids, polysaccharides, and low fatty acids in water extracts were increased. As fermentation in composting process depends on initial C/N ratios in water extracts of two samples were increased because of increased water-soluble TOC. From these results, it was revealed that solid state fermentation reactor using microbial additives can be used in composting process of organic wastes with broad C/N ratio.

• 미생물학회지
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• 제53권3호
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• pp.170-179
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• 2017

차는 세계적으로 인기있는 음료로 불발효차(녹차), 반발효차(우롱차), 완전발효차(홍차)와 흑차(미생물발효차 or 후발효차)를 포함하고 구분된다. 미생물발효차는 차나무(Camellia sinensis)의 잎을 미생물 발효과정을 통해 제조된다. 삼국시대부터 전해 내려온 청태전은 한국 남해안지역에서 제조되며 돈차 또는 떡차로 불리는 독창적인 한국의 미생물발효차이다. 본 연구에서는 청태전에 우점하는 미생물군집구조 분석을 위해 16S rRNA 유전자를 이용하였다. 청태전에 우점하는 미생물은 ${\gamma}$-proteobacteria에 속하는 Pantoea sp.와 Klebsiella oxytoca가 우점하였다. 미생물 군집크기 분석을 통해 청태전의 미생물 군집크기가 다른 미생물발효차와 비교해 가장 큰 것을 확인하였다.

• 농업과학연구
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• 제43권3호
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• pp.387-393
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• 2016

This study was conducted to determine the fermentative characteristics of wheat bran inoculated with a starter culture of direct-fed microbes as a microbial wheat bran (DMWB) feed additive. Wheat bran was prepared with 1% (w/w, 0.5% Lactobacillus plantarum and 0.5% of Saccharomyces cerevisiae) starter culture treatment (TW) or without starter culture as a control (CW). Those were fermented under anaerobic conditions at $30^{\circ}C$ incubation for 3 days. Samples were taken at 0, 1, 2, and 3 days to analyze chemical composition, microbial growth, pH, and organic acid content. Chemical composition was not significantly different between CW and TW (p > 0.05). In TW, the number of lactic acid bacteria and yeast increased during the 3 days of fermentation (p < 0.05) and the population of lactic acid bacteria was significantly higher than in CW (p < 0.05). After 3 days, the number of yeast in TW was $7.50{\pm}0.07log\;CFU/g$, however, no yeast was detected in CW (p < 0.05). The pH values of both wheat bran samples decreased during the 3 days of fermentation (p < 0.05), and TW showed significantly lower pH than CW after 3 days of fermentation (p < 0.05). Contents of lactic acid and acetic acid increased significantly at 3rd day of fermentation in TW. However, no organic acids were generated in CW during testing period. These results suggest that 3 days of fermentation at $37^{\circ}C$ incubation after the inoculation wheat bran with starter culture makes it possible to produce a direct-feed with a high population of lactic acid bacteria at more than $10^{11}CFU/g$.