• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.390-393
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• 1990

A cellobiohydrolase was purified from the culture broth of Trichoderma uiride by using immunoaffinity chromatography. A single protein band in polyacylamide gel electrophoresis and isoelectrofocusing after immunoaffinity purification corresponded to cellobiohydrolase activity. A immunoaffinity purified cellobiohydrolase is more effective in the hydrolysis of highly crystalline cellulose than amorphous cellulose.

• The Microorganisms and Industry
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• v.20 no.2
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• pp.15-19
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• 1994

전기투석은 전하를 갖는 막과 전위차가 존재하는 장치에서 전해질을 분리하는 공정이다(fig. 1). 전기투석은 1980년대 이전까지는 주로 담수제조, 소금제조와 같은 무기이온제거에 사용되었으나 1980년대 들어 식품제조, 의약제조, 생물공정, 폐수처리 공정 등 다양한 방면으로 응용범위를 넓혀가고 있다. 전통적인 전기투석은 염, 산, 염기들을 수용액상에서 분리하거나 농축하는데 사용되었지만 근래에는 아미노산, 단백질을 분리하는데 전기투석의 활용연구가 시도되고 있다. 본 논문에서는 전기투석의 새로운 응용분야인 전기투석생물반응기에 대해 간단한 설명과 1980년대 후반부터의 연구논문의 소개, 그리고 전기투석에서의 간단한 물질전달이론 설명을 시도하고자 한다.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.345-354
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• 2001

The effects on arsenic geochemistry of indigenous microorganisms isolated from an area contaminated with high concentration of arsenic were investigated. Arsenite exerted higher inhibitory effects on the microbes' growth than arsenate. During incubation of the microbes in an arsenate-spiked medium over 24 hours, decrease in microbial growth was observed as arsenate content increased. Arsenate of 150 mM or over apparently inhibited cell growth. However, further incubation for up to 4 days in the high arsenate concentration medium resulted in cell growth, implying that the microorganisms adjusted their biochemical functions to detoxify arsenic and maintain growth. Two types of microbes were observed during 20 hours to reduce arsenate to arsenite in solution through a detoxification mechanism. As well, decrease in the total arsenic content occurred over a 4-day incubation with the same microbes in an arsenate-spiked medium. Therefore it is suggested that microorganisms can influence arsenic speciation in natural settings and this may be applied to efficient bioremediation of arsenic-contaminated sites.

• KSBB Journal
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• v.18 no.6
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• pp.466-472
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• 2003

Several microorganisms were isolated and characterized for the development of fermentation accelerator of animal manure. Firstly, 61 species were isolated from rice bran extract. Secondly, five strains of microorganisms were screened by the analysis of hydrolysis activities for organic compounds including protease, cellulase, amylase, and lipase. From a deodorization test for ammonia gas using the isolated strains, finally three bacterial strains were selected (NA 2, 12, 15). The selected strains, NA 2 and 15 were identified as Bacillus acidocaldarius and Planococcus sp. respectively. The media composition of key nutrients and pH for the mixed culture of the three selected strains were optimized using an experimental design method (response surface method) as follows : beef extract (4.59g/L), peptone (8.72g/L) and pH 6.3. Consequently, the isolated microorganisms seem to have potential applicability in the animal manure treatment.

• The Korean Journal of Mycology
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• v.18 no.1
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• pp.20-25
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• 1990

For the purpose of obtaining microorganisms producing high fructosyl transferase, the screening test was carried out. Among more than three hundred isolates, an isolate (C23-isolate) was selected for high fructosyl transferase producer from the dirts at the coffee vendig machine. The morphological and cultural characteristics of the isolate C23 on various culture media were studied and identified as Aureobasidium pullulans var. melanigenum.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.187-191
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• 2003

In an attempt to isolate myxobacteria from soil samples, we isolated swarm and fruiting body forming bacteria that have bacteriolytic activity on Coli-spot agar plate. For the classification of myxobacteria, 16S rDNA RFLP patterns were analyzed. Amplified 16S rDNAs of myxobacteria type strains (Family I, II, III and IV), negative control strains and soil-isolates were restricted with HaeIII, EcoRI and EcoRV, respectively. We found that the soil-isolates belongs to myxobacteria Family I, II, III.

• Membrane Journal
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• v.20 no.3
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• pp.173-184
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• 2010

Microbial fuel cell (MFC) is a promising renewable energy source that can generate electrical energy from organic wastes using microbe. This technology has been regarded as a future green alternative energy in that MFC makes use of organic-rich wastewater and also reduces waste sludges as well as produces electricity. To be practically realized, however, achieving higher power density than now is demanded, which may be possible by eliminating various negative factors to act as resistances in MFC operations. For instance, highly activated microbes, highly conductive electrode materials, and fast electron transfer between microbes and electrodes can lead to MFC with high power density. In particular, polymer electrolyte membranes are also a key component for improved MFC performance.

• Korean Journal of Microbiology
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• v.33 no.2
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• pp.131-135
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• 1997

Several microorganisms capable of producing protopectinase, which catalyzes dissociation of plant tissue to single cells, were isolated from soils. Crude enzymes prepared from culture supernatants of the strains released potato cells as a single cell from potato tissues. One of the isolated strains showing higher activity of protopectinase was selected and identified as Rhizopus sp. from the morphological characteristics. For preparing single cells from potato tissues, optimum enzyme activity of protopectinase, which was prepared from culture filtrate of Rhizopus sp. R2, was obescrved at $40^{\circ}C$ and pH 4.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.1
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• pp.103-108
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• 2023

In this study, basic research was conducted to secure microbial resources applicable to autonomous crack healing concrete. To this end, in this experiment, biomineral-forming microorganisms were separated from natural sources, and the ability of survival in cement and calcium carbonate precipitation were compared to secure suitable microbial resources. Bacillus-type bacteria forming endospores were isolated from the sample, and the amount of calcium carbonate produced by the six microorganisms identified by 16S rRNA sequencing was compared. Two types of microorganisms, Bacillus velezensis and Bacillus subtilis, with the highest calcium carbonate precipitation were selected, and the survival of the microorganisms was confirmed through phase contrast microscopy after being cured after being added to the mortar. In addition, it was confirmed that the autonomous crack healing capability by the crack healing material produced by microorganisms was confirmed by artificially generating cracks in the mortar.

• Journal of Korean Society of Archives and Records Management
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• v.1 no.1
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• pp.231-243
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• 2001

The sterilization method of records by fumigation using mixed gas of methyl bromide(MB) and ethylene oxide(ETO) has been generally used as a way to protect biological deterioration by microorganisms and insects. In this study, we confirmed sterilization effect of MB and ETO [86 : 14(Vol.%)] on and analyzed toxicity on microorganisms isolated from records. To analyze sterilization effect of fumigation on microorganisms and insect, we have fumigated microorganisms and insect with a various amounts mixed gas of MB and ETO, and various exposure time. Insect was sterilized at all experimental conditions. In microorganisms, sterilization effect was detected only when the mixed gas was treated at $120g/m^3$ concentration for at least 24 hrs. To test the possibility of isolated microorganisms as a threat to human health, it was investigated that toxicity test using yeast, radish and cancer cells on microorganisms. Only Aspergillus oryzae had an inhibition effect on growth of yeast. radish and cancer cells, respectively. These results demonstrate that sterilization effect can occur at low concentrations of the mixed gas on insect but requires higher concentrations of the mixed gas on microorganisms. In addition to, it is suspected that the possibility of the microorganism as a threat to human health is little.