• Journal of Microbiology
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• 제35권3호
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• pp.193-199
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• 1997

From several industrial wastewaters, 14 bacterial strains which degrade benzene, toluene, o-xylene, m-xylene, or p-xylene (BTX) were obtained. These strains were characterized as to their species composition and the substrate range, kinetic parameters and the substrate interactions were investigated. Although BTX components have a similar chemical structure, isolated strains showed different substrate ranges and kinetic parameters. None of the strains could degrade all of BTX components and most of them showed an inhibition (Haldane) kinetics on BTX, BTX mixtures were removed under inhibitory substrate interactions with variation in the intensity of inhibition. For a complete degradation of BTX, a defined mixed culture containing three different types of patyways was constructed and all of the BTX components were simultaneously degraded with the totla removal rate of 225.69 mg/g biomass/h Judging from the results, the obtained mixed culture seems to be useful for the treatment of BTX-contaminated wastewater or groundwater as well as for the removal of BTX from the contaminated air stream.

• 한국토양비료학회지
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• 제26권4호
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• pp.265-270
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• 1993

우리나라 토양에서 분리(分離)된 수종(數種) YCK균주(菌株)의 경합여건(競合與件)에 따른 공중실소고정(空中室素固定) 즉 공생효과(共生效果) 변화양상을 조사코자, 우리나라 장백(長白)콩과 미국(美國)의 Clark콩에 대하여 YCK균주(菌株)를 단독(單獨) 및 USDA균주(菌株)와 혼합접종(混合接種)한 결과는 다음과 같았다. 1. YCK균주(菌株)들은 단독접종시(單獨接種時) 보다 USDA균주(菌株) 특히 USDA 110균주(菌株)와 혼합접종(混合接種)했을 때 공생효과(共生效果)의 증가 경향을 보였다. 2. YCK균주(菌株)와 USDA균주(菌株)의 혼합접종(混合接種) 조합별(組合別) 공생효과(共生效果) 경향은 대두품종에 따라 상이하였다. 3. YCK균주(菌株)들은 근류형성경함력(根瘤形成競含力)에 있어서 USDA110균주(菌株)보다 우수하였으나 USDA 127균주(菌株)보다는 저조하였다. 4. 공시(供試)된 YCK균주중(菌株中) 우리나라 장백(長白)콩에서 공생효과(共生效果)가 우수하였던 것은 단독접종시(單獨接種時) YCK 213, YCK균주(菌株)와 혼합접종시(混合接種時)는 YCK 141균주(菌株)였다 5. YCK균주(菌株)들는 USDA 123균주(菌株)와 혼합접종(混合接種)했을 때 근류형성상(根瘤形成上)의 길항작용(拮抗作用)을 보였다.

• 한국식품과학회지
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• 제29권1호
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• pp.150-155
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• 1997

소다 크레커에서 분리된 미생물은 대부분 젖산균인 Lactobacillus의 속이므로 약 20종의 기존에 분리된 Lactobacillus속의 미생물들을 스폰지 발효에 사용하였고, 이중에서 발효후 이취가 없고 총적정산도가 높은 6종의 젖산균을 선별하였다. 선별된 젖산균은 소다 크레커의 스폰지발효에 관여하는 주요 젖산균으로 보고된 L. brevis, L. delbrueckii, L. fermentum, L. leichmanii와 L. plantarum 등 5종과 San Francisco sour bread의 주요 젖산균인 L. sanfrancisco이었다. 선별된 6종의 젖산균을 10%의 밀가루 용액에 접종하여 스폰지 발효 동안의 pH, 총적정산도 및 유기산(lactic acid와 acetic acid)의 변화를 측정한 결과 L. brevis, L. fermentum과 L. plantarum의 pH는 많이 저하하였고 총적정산도는 많이 증가하였으며 L. delbrueckii의 경우는 유기산이 빨리 생성되었고 주 유기산인 acetic acid를 비교적 많이 생성하여 혼합균주의 조합으로 사용하였다. 4가지 균주의 여러 가지 조합중 L. brevis, L. fermentum과 L. plantarum의 혼합젖산균을 사용한 결과 총적정산도의 상승과 pH의 저하와 acetic acid의 생성력이 가장 뛰어나 이 혼합젖산균을 최적 스폰지 발효를 위한 가장 좋은 혼합젖산균으로 선택하였다.

• 한국키틴키토산학회지
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• 제23권4호
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• pp.285-292
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• 2018

음식물쓰레기 분해용 균주를 선발하기 위하여 전통발효식품과 토양으로부터 내염성, 내열성을 갖는 균주 분리를 시도하였으며, protease, amylase, cellulase 및 lipase의 효소활성도를 평가하였다. 5% NA 배지에서 분리된 균주는 212종이었으며, 전통발효식품의 경우 4가지 효소활성을 가지고, 토양의 경우 2가지 이상의 효소활성을 가지며, 억제환이 15 mm 이상의 크기를 지닌 79종의 균주를 우선 선발하였다. 선발된 균주를 대상으로 분자유전학적 동정을 진행한 결과, 중복성을 배제하여 11종의 균주를 최종적으로 선발하여 혼합균주로 사용하였다. 혼합균주의 최적 배양조건으로는 배양시간은 24시간, 배양온도는 $30^{\circ}C$ 그리고 pH의 최적 조건은 7.0 부근인 것으로 확인되었다. 최적배양된 혼합균주 처리에 따른 음식물쓰레기 분해능 평가 결과 멸균수 첨가군은 10 mesh ($2000{\mu}m$)에서 103 g, 혼합균주 첨가군은 10 mesh ($2000{\mu}m$)에서 18 g인 것으로 보아 혼합균주로 나타나 음식물의 고형분의 입자가 액상으로 분해되었음을 확인하였다.

• Journal of Applied Biological Chemistry
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• 제57권4호
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• pp.313-320
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• 2014

Black liquor (BL) is a by-product of rice straw pulping process. It is a low costs raw material for production value-adding proteins and enzymes, which has been paid more and more attention to reduce its environmental pollution. Mixed cultures of micelial fungi, Trichoderma reesei Northern Regional Research Laboratory (NRRL)11236, Trichoderma reesei NRRL 6165 and Aspergillus niger strains NRC 5A, NRC 7A, and NRC 9A were evaluated for their ability to produce xylanase using crude hemicellulose (CHC) prepared from BL and peat moss as an inert support under solid state fermentation (SSF). The most potent strains, A. niger NRC 9A (818.26 U/g CHC) and T. reesei NRRL 6165 ($100.9{\pm}57.14$ U/g CHC), were used in a mixed culture to enhance xylanase production by co-culturing under SSF. In the mixed culture, xylanase production ($1070.52{\pm}12.57$ U/g CHC) was nearly1.3 and 10.6-fold increases over the activities attained in their monocultures, A. niger NRC 9A and T. reesei NRRL 6165, respectively. Optimization of the culture parameters of the mixed culture SSF process, concentration of ammonium sulfate and corn steep liquor, CHC/peat moss ratio, inoculum size and ratios of the two strains, initial pH value, initial moisture content and incubation time, exhibited a significant increase ($2414.98{\pm}84.02$ U/g CHC) in xylanase production than before optimization.

• 한국식품과학회지
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• 제43권4호
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• pp.518-523
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• 2011

본 연구를 통해서 부추와 마늘의 생즙과 가루의 항균활성은 농도의존적으로 증가되어짐을 확인할 수 있었고, 그람음성균인 Escherichia coli, Salmonella enteritidis 보다 그람양성균인 Staphylococcus aureus 에 대한 항균력이 높음을 알 수 있었다. 부추는 생즙에 비해 가루의 항균활성이 떨어졌고, 마늘은 생즙과 가루의 활성이 유사하게 분석됨으로써, 냉동건조 후에도 항균활성이 유지됨을 확인할 수 있었다. 부추와 마늘간의 항균활성을 비교해보면, 생즙과 가루 형태에서 모두 부추보다 마늘의 항균활성이 높게 나타났다. 부추와 마늘 모두 항균활성 온도가 높을수록, 가열 시간이 길어질수록 저하되었고, 마늘가루가 부추가루보다 약한 열 안정성을 보였다. 또한 부추와 마늘 모두 pH에 따른 항균성의 변화는 일정하게 유지되어 pH 변화에 대해서는 비교적 안정한 것으로 나타났다. 부추와 마늘생즙, 부추와 마늘가루의 혼합 비율에 따른 항균성의 변화는 마늘비율의 증가에 따른 효과가 나타날 뿐, 시료간 혼합에 따른 상승효과는 나타나지 않았다. 또한 부추와 마늘가루는 복합균주에서 각각의 균주에 대해여 항균활성을 나타내었으며, 이는 단일균주에 나타난 항균활성과 유사한 것으로 나타났다.

• Parasites, Hosts and Diseases
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• 제48권1호
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• pp.23-33
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• 2010

An understanding of the nature of the immune response to asexual erythrocytic stages of malaria parasites will facilitate vaccine development by identifying which responses the vaccine should preferentially induce. The present study examined and compared the immune responses of NIH mice in either single or mixed infections with avirulent (DK) or virulent (DS) strains of Plasmodium chabaudi adami using the ELISA test for detecting and measurement of cytokines and antibody production. In both single and mixed infections, the study showed that both cell- and antibody-mediated responses were activated. In all experiments, an early relatively high level of IFN-$\gamma$ and IgG2a during the acute phase of the infection, and later elevation of IL-4 and IgG1, suggested that there was a sequential Th1/Th2 response. However, in the avirulent DK strain infection a stronger Th1 response was observed compared to the virulent DS strain-infection or in mixed infections. In the virulent DS infection, there was a stronger Th2 response compared to that in the DK and mixed infections. The faster proliferation rate of the virulent DS strain compared to the DK strain was also evident.

• 한국연초학회지
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• 제18권1호
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• pp.60-65
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• 1996

Chemicals including antibiotics and bactericides were screened for suppression of streptomycin-resistant Erwinia cmutouom subsp. cmutovom (Ecc) strains in laboratory and field conditions. Oxytetracycline, ethoquinolac and dichlorophen suppressed the growth of streptomycin-resistant Ecc strains in vitro. Fractional inhibitory concentration (FIC) indices of oxytetracycline and ethoquinolac mixed with streptomycin against the Ecc strains were equal to and less than one, respectively. Consequently the efficacy of those chemicals in mixture with sorptomycin were non-antagonistic But that of dichlorophen mixed with streptomycin was more than one, therefore the efficacy of the mixture was antagonistic. Spray of oxyteoucycline, ethoquinolac and agrimycin-100 on the topped burley tobacco plants was efficacious in reducing tobacco hollow stalk at the same level of sorptomycin treatment in three-year field trials, which suggests that those are promising chemicals to be alternative to streptomycin for control of tobacco hollow stalk.

• 한국미생물·생명공학회지
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• 제22권4호
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• pp.415-422
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• 1994

The biodegradation of aromatic compounds by a mixed culture GE1 was investigated in an artificial wastewater containing 250 mg/l of benzene, toluene, and phenol in semicontinuous culture. In the control group (no strains) with an aeration rate of 75 ml/l/min, 37% of phenol and 83% of benzene were volatilized during early 24 hrs and toluene was disappeared from the medium within 12 hrs. The biodegradation of benzene and toluene was effective in SB (strains + biofilm) treatment, while phenol was degraded more quickly in SG (strains + glucose) treatment including glucose as an additional carbon source. aromatic compounds added at a concentration of 250 mg/l were completely removed by SG treatment after 16 hrs or 32 hrs, respectively. The removal rate of COD was high as much as 80 mg/l/h in SG treatment during early period, but COD revealed a stable value of 116~140 mg/l after 12 hrs caused by increased biomass. Therefore, it is concluded that the mixed GE1 could be used for the wastewater treatment including aromatic compounds such as benzene, toluene, and phenol.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.685-691
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• 1994

The biodegradation of aromatic compounds by mixed and monoculture was investigated in an artificial wastewater containing 500 mg/l of benzene(B), phenol(P), and toluene(T) in various combinations. None of three strains utilized P-xylene(X) as a carbon source, but they grew well on p-xylene in mixtures with benzene and toluene. In the mixed culture on mixed substrate, the length of lag phase was different depending on the nature of mixture. Cell growths of Flavobac- terium sp. BEN2 and Acinetobacter sp. GEM63 were inhibited in the presence of a 500 mg/l of phenol. When the mixed culture of three strains was cultured in a bench-scale reactor containing artificial wastewater, each of benzene, phenol, and toluene was not detected at 30 hrs, 50 hrs, and 12 hrs after incubation in the treatment. The removal rates of COD$_{t}$(total COD) and COD$_{s}$,(soluble COD) of upper phase after centrifugation during early 50 hrs were ca. 80% and ca. 93.8%, respectively.