• 생약학회지
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• 제23권3호
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• pp.142-145
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• 1992

MeOH extract of twenty medicinal herbs were screened for their effects against protein kinase C (PKC) using bleb-forming assay and PKC enzyme assay. Smilax china and Sanguisorba officinalis showed potent anti-PKC activity. Campsis grandiflora and Galla Halepensis showed moderate inhibitory effect on PKC.

• 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.

• 생명과학회지
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• 제8권1호
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• pp.67-71
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• 1998

다량의 시료를 빠르게, 적은 격비로, 간다히 검색할수 있는 예비선별법을 찾던중, ccDNA와 sulforhodamine B를 각각 사용한 미생물배양액내의 신규항암후보물질의 탐색을 시도하였다. cccDNA법으로는 3.3%가 positive 반응을 나태내었으며, SRB assat에서는 A549와 SK-OV-3에 활성을 나타내는 4개의 발효여액을 확인한수 있었다.

• 생명과학회지
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• 제15권3호
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• pp.332-336
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• 2005

4-(p-Nitrobenzyl)pyridine (NBP)의 색깔변화를 이용한 epoxide hydrolase활성 측정법을 사용하여 다양한 미생물 세포유래의 epoxide hydrolase 활성을 측정하고 평가하였다. Epoxide hydrolase의 가수분해 반응에 의해 분해되고 남은 에폭사이드 기질에 의한 NBP alkylation 반응을 통한 색깔변화로 손쉽게 epoxide hydrolase 활성을 측정할 수 있었다. NBP 반응에서 triethylamine을 첨가하여 색깔반응 효율을 높일 수 있었으며, 10mM styrene oxide에 대한 최적 세포 사용량은 12.5mg/ml로 결정하였다. 본 연구에서 얻은 colorimetric assay조건에서 대용량의 미생물 후보군집으로부터 유용한 epoxide hydrolase를 가지는 신규 미생물을 효율적으로 선별할 수 있을 것으로 기대된다.

• 한국식품과학회지
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• 제31권5호
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• pp.1345-1348
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• 1999

고등어의 저장중 표피 오염 미생물 수를 신속하게 측정하여 신선도 판정을 위한 자료로 활용하고자 ATP bioluminescence assay에 의한 측정가능성을 파악하고자 하였다. 고등어를 $1^{\circ}C$에 저장하면서 표피를 swabbing 방법에 의해 미생물을 분리하여 총균수의 변화와 ATP bioluminescence assay에 의한 RLU 값을 측정하여 상관관계를 측정하여 본 결과 0.90 이상의 regression coefficient를 나타내어 유의적인 관계가 있음을 알 수 있었다. 따라서 ATP bioluminescence assay는 고등어 표피 오염 미생물의 신속 측정 방법으로 적합함을 알 수 있었으며 이 방법을 사용하였을 경우 기존의 48시간 이상 소요되는 전통적인 plate count 방법에 비하여 전처리를 포함하여 30분 이내에 결과를 알 수 있는 매우 신속하고 정확한 측정방법임을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1114-1118
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• 2015

Microbial fuel cells (MFCs) have gathered attention as a novel bioenergy technology to simultaneously treat wastewater with less sludge production than the conventional activated sludge system. In two different operations of the MFC and aerobic process, microbial growth was determined by the protein assay method and their biomass yields using real wastewater were compared. The biomass yield on the anode electrode of the MFC was 0.02 g-COD-cell/gCOD-substrate and the anolyte planktonic biomass was 0.14 g-COD-cell/g-COD-substrate. An MFC without anode electrode resulted in the biomass yield of 0.07 ± 0.03 g-COD-cell/g-CODsubstrate, suggesting that oxygen diffusion from the cathode possibly supported the microbial growth. In a comparative test, the biomass yield under aerobic environment was 0.46 ± 0.07 g-COD-cell/g-COD-substrate, which was about 3 times higher than the total biomass value in the MFC operation.

• 한국균학회지
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• 제8권1호
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• pp.69-71
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• 1980

To establish a competent method of microbiological assay for bacampicillin, one of new semi-synthetic derivatives of ${\beta}-lactam$ antibiotics, a comparison was carried out between different conditions for hydrolysis of bacampicillin into ampicillin which was then subjected to cylinder plate method. The results showed that the use of carboxylic ester hydrolase in vitro as a pretreatment of it in either pH value 6 or 8 was feasible and that the cylinder plate method with Sarcina lutea was adequate for potency estimation.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.689-689
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• 2003

• Journal of Microbiology
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• 제44권4호
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• pp.403-408
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• 2006

The purpose of this study was to determine the efficacy of a nucleic acid sequence-based amplification (NASBA) method of detecting noroviruses in artificially and naturally contaminated shellfish. We used 58 fecal samples that tested positive for noroviruses with electron microscopy (EM) to develop an NASBA assay for these viruses. Oligonucleotide primers targeting the polymerase coding region were used to amplify the viral RNA in an isothermal process that resulted in the accumulation of RNA amplicons. These amplicons were detected by hybridization with digoxigenin-labeled oligonucleotide probes that were highly specific for genogroup I (GI) and genogroup II (GII) of noroviruses. The expected band of 327bp appeared in denaturing agarose gel without any nonspecific band. The specific signal for each amplicon was obtained through Northern blotting in many repeats. All fecal samples of which 46(79.3%) belonged to GII and 12(20.6%) belonged to GI were positive for noroviruses by EM and by NASBA. Target RNA concentrations as low as 5pg/ml were detected in fecal specimens using NASBA. When the assay was applied to artificially contaminated shellfish, the sensitivity to nucleic acid was 100pg/1.5g shellfish tissue. The potential use of this assay was also confirmed in naturally contaminated shellfish collected from different ponds in Guangzhou city of China, of which 24 (18.76%) out of 128 samples were positive for noroviruses; of these, 19 (79.6%) belonged to GII and 5 (20.4%) belonged to GI. The NASBA assay provided a more rapid and efficient way of detecting noroviruses in fecal samples and demonstrated its potential for detecting noroviruses in food and environmental samples with high specificity and sensitivity.

• Journal of Microbiology and Biotechnology
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• 제25권11호
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• pp.1928-1935
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• 2015

Microbial growth kinetics is often used to optimize environmental processes owing to its relation to the breakdown of substrate (contaminants). However, the quantification of bacterial populations in the environment is difficult owing to the challenges of monitoring a specific bacterial population within a diverse microbial community. Conventional methods are unable to detect and quantify the growth of individual strains separately in the mixed culture reactor. This work describes a novel quantitative PCR (qPCR)-based genomic approach to quantify each species in mixed culture and interpret its growth kinetics in the mixed system. Batch experiments were performed for both single and dual cultures of Pseudomonas putida and Escherichia coli K12 to obtain Monod kinetic parameters (μ_max and K_s). The growth curves and kinetics obtained by conventional methods (i.e., dry weight measurement and absorbance reading) were compared with that obtained by qPCR assay. We anticipate that the adoption of this qPCR-based genomic assay can contribute significantly to traditional microbial kinetics, modeling practice, and the operation of bioreactors, where handling of complex mixed cultures is required.