• 한국미생물·생명공학회지
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• 제22권4호
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• pp.347-352
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• 1994

Cytotoxic test was performed by SRB assay on human epidermoid carcinoma HEp-2 cell line for screening the soil microorganism, secreting anticancer agent. One microorganism was selected among two thousand microorganisms for its highest cytotoxicity. And this microorganism was identified with Streptomyces species after performing of diaminopimeric acid and reducing sugar analysis of cell wall and analysing the cultural characteristics and named Streptomyces sp. SM 1119. The effect of anticancer agent in SM 1119 culture extract on the cell cycle was studied by using GG$_{o}$ synchronized NIH 3T3 cells. The extract inhibited the serum stimulation of GG$_{o}$ NIH 3T3 cell only within 1 hour after serum stimulation but not after 6 hours. The extract also reduced the amount of c-myc mRNA in Colo 320 cell. These results suggest that the anticancer agent in the extract inhibits the progression of cell cycle very early stages, probably from G$_{0}$ to G$_{1}$.

• 한국미생물·생명공학회지
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• 제37권4호
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• pp.408-412
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• 2009

A study on the screening and isolation of microorganism was performed for the removal of main malodor, such as ammonia, produced from the livestock farm. The main malodor components in livestock farm are ammonia, volatile fatty acids, sulfur compounds and trimethylamine. Damages to man and livestock were originated from malodors mainly due to ammonia, and thus ammonia reduction experiments were performed. Sludge of sewage treatment plant was inoculated in the sesame dregs culture, from which ammonia gas was produced. An aerobically grown, pure cultured isolated from the 10th enrichment culture was analyzed by 16S rRNA sequencing and identified as Alcaligenes sp. NS-1. This strain NS-1 precultured in the sesame dregs was found to remove ammonia gas with an efficiency of approximately 99-100% at an average concentration of 40 ppmv of ammonia gas. When the strain NS-1 sprayed to pig excrements, the removal efficiency at an average concentration of 100 ppmv of ammonia was approximately 60% after 16 hr.

• 한국균학회지
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• 제15권3호
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• pp.169-174
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• 1987

생전분 당화효소 생산능이 우수한 균주를 얻기위하여 방앗간의 폐수, 주정회사의 폐수와 산성막걸리 공장의 토양 등에서 생전분 당화효소 생산능이 있는 효모 29종, 세균 35종, 곰팡이 40종을 순수분리하고 이들중에서 가장 생전분 당화력이 강한 곰팡이 1종을 선정하여 동정한 후 효소생산 조건과 pH 안정성을 측정한 결과는 다음과 같다. 1. 생전분 당화효소 생산능이 가장 강한 분리균주는 Aspergillus sp. SN-871로 동정되었다. 2. 효소생산 조건은 pH 4.0, 온도 $30^{\circ}C$와 배양기간이 5일 일때 가장 좋았다. 3. 탄소원으로 생전분 종류에서는 1% raw cornstarch 첨가시, 생전분 대신의 첨가에서는 0.5% frutose 첨가시 효과가 가장 좋았다. 4. 질소원으로는 0.1%의 $NaNO_3$ 첨가가 가장 효과가 좋았다. 5. 조효소의 pH 안정범위는 pH 2.0에서 pH 5.0까지가 비교적 안정하였다.

• 산업기술연구
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• 제7권
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• pp.59-68
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• 1987

In order to obtain a strain of producing lipase which has resistance against alkaline and detergent, a screening test was carried out. Among 500 strains isolated from soil samples, the strain J-19 was selected for this study. The composition of the optimum medium for the highest lipase production was 2.0% glycerin, 1.0% corn steep liquor, 2.0% yeast extract, 0.1% $MgSO_4$ $7H_2O$, 0.2% $K_2HPO_4$, 1.5% soybean oil and 0.1% LAS(linear alkylbenzene sulfonate) with initial pH value of 10.0 and 3-day cultivation at $25^{\circ}C$. The lipase activity of the strain J-19 under optimal condition was 3.3. units/ml, which was increased about 1.3-fold than that of basal medium.

• Archives of Pharmacal Research
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• 제21권3호
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• pp.278-285
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• 1998

The microdilution assay recommended by NCCLS (National Committee for Clinical Laboratory Standards) is one of the standardized methods of antibiotic susceptibility test. This method has been widely used clinically to obtain MIC values of antibiotics on pathogenic microorganisms. It is more convenient, rapid and simple to test many samples than other test methods such as agar diffusion assay and broth macrodilution assay. The screening of antimicrobial agents from microbial extracts is too laborious in its process. Therefore, a number of screening methods having more simple procedure have been developed. In our laboratory, we applied microdilution assay for screening the antimicrobial agents. This assay showed dose-response results and was more sensitive than disc diffusion assay in our system. We tested 200 samples of microbial extracts originated from 100 microbial strains and selected several samples as potential candidates. In this report, we show that the microdilution assay is more convenient method in screeing of antibiotic susceptibility than those previously reported.

• Bulletin of the Korean Chemical Society
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• 제30권12호
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• pp.2993-2998
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• 2009

An enzyme-linked immunosorbent assay (ELISA)-on-a-chip (EOC) biosensor combined with cell concentration technology based on immuno-magnetic separation (IMS) was investigated for use as a potential tool for early screening of Listeria monocytogenes (L. monocytogenes) in food products. The target analyte is a well-known pathogenic foodborne microorganism and outbreaks of the food poisoning typically occur due to contamination of normal food products. Thus, the aim of this study was to develop a rapid and reliable sensor that could be utilized on a daily basis to test food products for the presence of this pathogenic microorganism. The sensor was optimized to provide a high detection capability (e.g., 5.9 ${\times}\;10^3$ cells/mL) and, to eventually minimize cultivation time. The cell density was condensed using IMS prior to analysis. Since the concentration rate of IMS was greater than 100-fold, this combination resulted in a detection limit of 54 cells/mL. The EOC-IMS coupled analytical system was then applied to a real sample test of fish intestines. The system was able to detect L. monocytogenes at a concentration of 2.4 CFU/g after pre-enrichment for 6 h from the onset of cell cultivation. This may allow us to monitor the target analyte at a concentration less than 1 CFU/g within a 9 h-cultivation provided a doubling time of 40 min is typically maintained. Based on this estimation, the EOC-IMS system can screen and detect the presence of this microorganism in food products almost within working hours.

• Journal of Microbiology and Biotechnology
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• 제15권5호
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• pp.1140-1145
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• 2005

MJM383, a rare actinomycete sp. strain originated from Chinese soils, was isolated through an antimicrobial screening system. The analysis of 16S rDNA sequences and biochemical characterization determined the strain to belong to genus Kitasatospora. Both NMR and ESI mass data of its purified bioactive compounds revealed Kitasatospora sp. MJM383 to produce two antitumor agents, streptonigrin and oxopropaline G, which have been known to be produced from Streptomyces species. This is the first report to demonstrate the presence of antitumor agents produced by genus Kitasatospora.

• 약학회지
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• 제32권5호
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• pp.304-307
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• 1988

394 strains of soil microorganism were isolated from the Korean soil samples. The isolated strains were shake-cultured in oat-meal medium. The filtrates of the cultures were screened for the production of ${\alpha}-amylase$ inhibitors. Five strains were identified to produce ${\alpha}-amylase$ inhibitors. And these strains were identified as Actinomycetes.

• Journal of Microbiology and Biotechnology
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• 제5권5호
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• pp.264-268
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• 1995

Sulforhodamine B(SRB) assay was performed on the human lung carcinoma, A549 cell line to screen soil microorganisms for production of anti-cancer agent. Among 4, 265 microorganisms, 45 isolates were selected for their cytotoxicity and tested for their effects on the expression of c-myc by RNA slot blot and Northern blot analysis resulting in selection of No.2303 isolate. This No.2303 was identified as Streptomyces sp. by ISP classification and the chemotaxonomic analysis method. NO.2303 inhibited the expression of cmyc in Col0320 DM and A549 cell lines. The culture extract of No. 2303 also inhibited the progression of the cell cycle of Go in NIH 313 cells, implying that the extract also inhibited the expression of c-myc in NIH 313 cell.

• 한국미생물·생명공학회지
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• 제25권6호
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• pp.586-591
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• 1997

In the course of screening for the tipA promoter-inducing substances, we isolated an active compound, sulfomycin Ia, from the mycelium of a microorganism designated 50634. The producing organism was identified as Streptomyces sp. on the basis of taxonomic studies. Sulfomycin Ia was purified from mycelial extract by silica gel column chromatography, LH-20 column chromatography, silica gel TLC, and preparative HPLC. The molecular weight of sulfomycin Ia was determined to be m/z 1129 (M+Na)$^{+}$ by FAB mass measurement and $^{1}$H NMR spectroscopic analysis. The structure was assigned as a derivative of sulfomycin I with thiazole, methyloxazole, oxazole, and pyridine rings by $^{1}$H NMR spectral data.