• Journal of Applied Biological Chemistry
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• 제43권4호
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• pp.207-210
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• 2000

As a typical example of the screening for a microbial biocatalyst from nature, isolation of nitrilesynthesizing microorganisms, characterization of a new enzyme aldoxime dehydratase, and its function in the aldoxime-nitrile pathway are introduced. Catalytic properties of some of our enzymes were improved through a direct evolutionary approach.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.101-110
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• 1998

The extent of biological diversity being revealed by molecular techniques accentuates the need to develop methods to isolate and culture the large numbers of microorganisms that remain to be studied. The discovery and characterization of novel microorganisms will provide information useful in understanding microbial ecosystems and have the potential to lead to new products for the biotechnology industry. In this review, the use of innovative techniques and exploration of unusual ecosystems, that have begun to address the challenge of isolating the "uncultured" members of the microbial population, are examined.

• 한국수산과학회지
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• 제44권4호
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• pp.325-331
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• 2011

Nonylphenol (NP), which is well known as an endocrine disrupter, has been detected widely in untreated sewage or waste water streams. Given the necessity of discovering an eco-friendly method of degrading this toxic organic compound, this study was conducted to isolate NP-degrading microorganisms from the aqueous environment. NP-degrading microbes were isolated through NP-containing enrichment culture. Finally, a microbial consortium, SW-3, capable of degrading NP with high efficiency, was selected from the mixture sample. The microbial consortium SW-3 was able to degrade over 99% of 100 ppm NP in the culture medium for 40 days at $25^{\circ}C$. The microbial consortium SW-3 seemed to utilize NP as a carbon source, since NP was the sole carbon source in the culture medium. In order to isolate the NP-degrading bacterium, we further conducted single colony isolation using the microbial consortium SW-3. Four strains isolated from SW-3 exhibited lower NP-degradation efficiency than that of SW-3, suggesting that NP was degraded by the co-metabolism of the microbial consortium. We suggest that the microbial consortium obtained in this study would be useful in developing an eco-friendly bioremediation technology for NP degradation.

• 한국미생물·생명공학회지
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• 제20권1호
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• pp.110-113
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• 1992

In the screening process of anti- or desmutagenic substance from the various microbial metabolites with the method of Ames and Rec-assay, a desmutagenic substance producing bacterial strain which inactivates the mitomycin C-induced mutagenicity was isolated and identified as Psudomonas sp. AM-10.

• 생명과학회지
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• 제22권6호
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• pp.723-729
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• 2012

난배양성 미생물의 배양과 보다 다양한 미생물의 분리를 위하여 Filter plate microbial trap (FPMT)을 개발하였고, 이 장치를 사용하여 Greenland의 토양에서 세균을 분리하였다. FPMT는 배지와 하단부의 membrane filter(0.45 ${\mu}m$ pore size)로 구성되어 있다. 시료에 포함된 세균과 화학물질이 FPMT 내로 이동하고, 세균이 증식하는 원리이다. 그 결과, FPMT를 이용한 새로운 in situ 배양방법을 통해 통상적인 Petri dish 배양방법보다 더 많은 종과 기존의 방법으로는 배양할 수 없는 세균을 분리하였다. 이 장치는 앞으로 다양한 환경에서 난배양성 미생물을 분리하는데 유용함을 확인하였다.

• Natural Product Sciences
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• 제21권3호
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• pp.170-175
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• 2015

The present study aims to detect the rare flavonoids isolated from the leaves of Persicaria glabra. The known flavonoids: quercetin (1), isorhamnetin (2), avicularin (3) and new one isorhamnetin-3-O-α-L-(6''-E-p-coumaroyl)-rhamnoside (4) were identified by HPLC, UV, IR and NMR. P. glabra has used traditionally for its analgesic, anti-inflammatory and anti-rheumatic properties. To find out the ingredients responsible for the efficiency of this plant, we have used to study the anti-microbial and anti-inflammatory activities of different extracts.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.356-358
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• 2011

• 한국미생물·생명공학회지
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• 제24권2호
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• pp.178-184
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• 1996

Dryfilm method by using 3M Petrifilm$^{TM}$ has been examined to replace conventional agar method for isolation of microorganisms from foods. The objectives of the present study were to evaluate suitability of dryfilm method as a microbial isolation method and to determine the effect of antimicrobial agent on dryfilm for isolation of microorganisms from foods. Five different foods, milk, ground beef, fishery surimi, Takju and wheat flour were used to isolate the natural microflora in foods and the inoculated Escheri chia coli. Standard method agar (SMA, Difco) and Petrifilm$^{TM}$ aerobic count (PAC, 3M) were used to isolate total microorganisms from foods. Violet red bile agar (VRBA), brilliant green lactose bile (BGLB) broth and Petrifilm$^{TM}$ coliform count (PCC, 3M) were used to isolate coliforms from foods. E. coli broth (EC broth) and Petrifilm$^{TM}$ E. coli count (PEC, 3M) were used to isolate E. coli from foods. Acidified potato dextrose agar (APDA) and Petrifilm$^{TM}$ yeast & mold count (PYMC, 3M) were used to isolate yeasts and molds from foods. Total aerobic plate counts isolated from five different foods by SMA and PAC (3M) were riot significantly different each other at P<0.05 level and were highly correlated each other ($\geq$0.96). Mugwort extract as an antimicrobial agent did not affect microbial enumeratiion of Dryfilm. Significantly higher number of coliform colonies were formed on VRBA than PCC (3M) from ground beef, but they were not significantly different in coliform colonies from milk samples. PCC (3M) and BGLB were not significantly different for enumeration of coliforms in milk and beef samples. Significantly higher number of E. coli were isolated by EC broth than PEC from ground beef, but these were not significontly different for enumeration of E. coli from milk. Yeast and mold counts isolated from Takju and wheat flour by APDA and PYMC (3M) were not significantly different at P<0.05 level. These data indicate that dryfilm method by using 3M Petrifilm$^{TM}$ can be successively used as an alternative to conventional agar method for enumeration of microorganisms in various foods.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2003년도 International Meeting of the Microbiological Society of Korea
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• pp.128-131
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• 2003

• Environmental Engineering Research
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• 제14권1호
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• pp.3-9
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• 2009

Microorganisms play an important role in the geochemical cycles, industry, environmental cleanup, and biotechnology among other fields. Given the high microbial diversity, identification of the microorganism is essential in understanding and managing the processes. One of the most popular and powerful method for microbial identification is comparative 16S rRNA gene analysis. Due to the highly conserved nature of this essential gene, sequencing and later comparison of it against known rRNA databases can provide assignment of the bacteria into the taxonomy, and the identity of its closest relatives. Isolation and sequencing of 16S rRNA genes directly from natural environments (either from DNA or RNA) can also be used to study the structure of the whole microbial community. Nowadays, novel sequencing technologies with massive outputs are giving researchers worldwide the chance to study the microbial world with a depth that was previously too expensive to achieve. In this article we describe commonly used research approaches for the study of individual microorganisms and microbial communities using the tools provided by Ribosomal Database Project website.