• Mycobiology
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• 제35권3호
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• pp.162-165
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• 2007

Thirty seven species of Fusarium were evaluated for their ability of producing extracellular enzymes using chromogenic medium containing substrates such as starch, cellobiose, CM-cellulose, xylan, and pectin. Among the tested species Fusarium mesoamericanum, F. graminearum, F. asiaticum, and F. acuminatum showed high ${\beta}$-glucosidase acitivity. Xylanase activity was strongly detected in F. proliferatum and F. oxysporum. Strong pectinase activity was also found in F. oxysporum and F. proliferatum. Amylase activity was apparent in F. oxysporum. No clear activity in cellulase was found from all the Fusarium species tested.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.132-136
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• 2004

The LAL (Limulus amebocyte lysate) test for the detection and quantification of endotoxin is based on the gelation reaction between endotoxin and LAL from a blood extract of Limulus polyphemus. The test is labor intensive, requiring dedicated personnel, a relatively long reaction time (approximately 1 h), relatively large volumes of samples and reagents and the detection of the end-point is rather subjective. To solve these problems, a miniaturized LOC (lab-on-a-chip) prototype, 62mm (L) ${\times}$ 18 mm (W), was fabricated using PDMS (polydimethylsiloxane) bonded to glass. Using this prototype, in which 2mm (W) ${\times}$ 44.3mm (L) ${\times}$ 100 $\mu\textrm{m}$ (D) microfluidic channel was constructed, turbidometric and chromogenic assay detection methods were compared, and the chromogenic method was found the most suitable for a small volume assay. In this assay, the kinetic-point method was more accurate than the end-point method. The PDMS chip thickness was found to be minimized to around 2 mm to allow sufficient light transmittance, which necessitated the use of a glass slide bonding for chip rigidity. Due to this miniaturization, the test time was reduced from 1 h to less than 10 min, and the sample volume could be reduced from 100 to ca. 4.4 ${\mu}$L. In summation, this study suggested that the LOC using the LAL test principle could be an alternative as a semi-automated and reliable method for the detection of endotoxin.

• 한국식품영양과학회지
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• 제39권5호
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• pp.764-768
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• 2010

식품공전에 Cronobacter sakazakii 분리배지로 등재되어 있는 3종의 분리배지에 대한 평가실험을 실시하였다. Chromogenic Enterobacter sakazakii agar, Enterobacter sakazakii agar가 VRBG agar에 비하여 뚜렷한 색택과 모양의 집락을 생성하였다. 3종의 분리배지 모두 30종의 Cronobacter sakazakii에 대한 sensitivity가 100%로 측정되었지만 Cronobacter sakazakii 이외의 Enterobacteriaceae 균주를 이용한 specificity 실험에서는 Chromogenic Enterobacter sakazakii agar, Enterobacter sakazakii agar가 100%로 측정되었지만 VRBG agar는 0%로 측정되었다. 인위적으로 접종한 식품에서의 회수율은 실험에 공시된 3종 배지에서 커다란 차이가 없었다.

• 한국환경보건학회지
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• 제36권2호
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• pp.141-147
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• 2010

Indicator bacteria of fecal pollution were enumerated and compared by various detection methods for influent and final effluent of a sewage treatment plant. Total coliforms were enumerated by four methods including most probable numbers, chromogenic enzyme substrate test, membrane filtration, and plate counts and were about $10^4$ for influent and $10^2{\sim}10^3\;CFU/ml$ for final effluent. Fecal coliforms ranged between $10^3$ and $10^4$ for influent and $10^2\;CFU/ml$ for effluent by chromogenic enzyme substrate test and membrane filtration. Fecal streptococci counts were 1-log less than fecal coliforms counts, $10^2{\sim}10^3$ for influent and $10^1\;CFU/ml$ for effluent. Total coliforms numbers by plate count both in influent and in effluent showed 1-log higher than by the other three methods. Statistical analysis revealed that numbers of total coliforms by plate count in final effluent had the highest average of correlation (r=0.778, p<0.01) compared with those by the other three methods. In addition, total coliforms numbers by plate count showed most significant correlation (r=0.835, p<0.01) with those by chromogenic test which is well-known as its highest recovery efficiency. These results suggest that the plate count would be the optimum detection method for total coliforms in wastewater treatment plants which are the only microbiological standard of final effluent from wastewater treatment plants in the Republic of Korea, considering economic aspects and difficulties in laboratories.

• KSBB Journal
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• 제18권5호
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• pp.429-433
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• 2003

LAL 측정용 chip을 제작하기 위해서 우선 시료의 부피 감소에 대한 비탁법과 비색법을 비교하였다. 비색법은 낮은 부피에서 높은 감도를 보여 주었으며 시료의 부피와 무관하게 같은 endotoxin의 농도에서는 같은 흡광도를 보인다는 결론을 얻었다. Endotoxin의 농도에 따른 표준곡선을 end point법과 kinetic point법을 비교한 결과 대한약전의 기준에 적합한 kinetic point법이 적합하였다. 이러한 기초 실험결과를 통해 PDMS LOC를 제작하여 LAL 시험을 수행하였다. LOC를 이용하여 더 짧은 시간과 더 작은 시료로 시험이 가능하도록 하였다. 특히 PDMS LOC는 복잡한 channel을 쉽게 만들 수 있을 뿐 아니라 mold를 이용하여 상용화를 위한 대량 생산이 가능하다. 따라서 PDMS를 이용한 LOC의 제작과 실험을 통해 기존의 수작업의 LAL 시험을 LOC를 이용한 다중시료 측정과 자동화의 가능성을 제시하였다.

• 한국균학회지
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• 제39권2호
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• pp.99-104
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• 2011

표고버섯의 육종은 두 개의 다른 모균주에 의한 교배와 버섯생산에 좋은 형질을 지닌 교잡균주의 선발이 요구된다. 본 연구에서는 서로 다른 두 계통의 표고 모균주에서 유래한 단핵균주와 이들 단핵균주간의 교배로부터 만들어진 교잡균주에 대하여 발색반응 배지를 이용하여 세포외 분해효소의 분비능력 정도를 비교하여 생화학적 특성이 우수한 균주를 선발할 가능성에 대하여 조사하였다. 모균주로부터 유래한 단핵균주들 간에 ${\beta}$-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, protease의 분비능력에 차이가 있음을 확인하였다. 교잡균주에 있어서도 단핵균주의 조합에 따라 효소 분비능력이 달라지는 것을 볼 수 있었다. 이에 따라 발색반응배지를 이용한 세포외효소 평가법이 표고의 육종과정 중에 생성되는 교잡균주들의 평가에 활용 할 수 있을 것으로 사료된다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.203.3-203
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• 2005

• Bulletin of the Korean Chemical Society
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• 제29권3호
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• pp.663-665
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• 2008

• 대한임상검사과학회지
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• 제45권1호
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• pp.1-4
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• 2013

Vancomycin-resistant enterococci (VRE) have emerged as important healthcare-associated infection since last two decades. ChromID VRE agar (cIDVA) is useful for VRE rectal swab screening. We investigated all VRE were isolated on the cIDVA. A total of 363 rectal swabs of 85 patients to test VRE screening were inoculated into bile-esculin (B-E) broth with $6{\mu}g/mL$ vancomycin. After 24 hours incubation, we subcultured B-E broths were changed to black onto cIDVA. All isolates were identified by the MICROSCAN and VITEK2. The vanA gene and vancomycin minimal inhibition concentration (MIC) were detected by PCR and E-test respectively. 277 E. faecium (84.7%), 16 E. faecalis (4.9%), 25 E. avium (7.6%), 8 E. gallinarum (2.4%) and 1 E. raffinosus (0.3%) were isolated. 10.3% of VRE detected on cIDVA were other than E. faecium and E. faecalis that presented various color from colorless to pale violet. All isolates contained vanA and vancomycin MIC were > $256{\mu}g/mL$. VRE isolates other than E. faecium and E. faecalis should be objective to the contact precautions for healthcare-associated infection control if they possess vanA gene. Due to emerging enterococci carrying vanA such as E. avium, E. gallinarum, and E. raffinosus, VRE surveillance should be expanded to all isolates on chromogenic agar.

• Mycobiology
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• 제39권2호
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• pp.129-132
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• 2011

To determine the optimal media conditions for the detection of the extracellular cellulase activity in Ganoderma neo-japonicum, we varied three media conditions: dye reagent, pH, and temperature. We evaluated the use of four dyes, Congo red, phenol red, remazol brilliant blue, and trypan blue. To observe the effect of pH on the chromogenic reaction, we tested media ranging from 4.5 to 8.0. To research the effect of temperature on the clear zone and the fungus growing zone, we tested temperatures ranging from 15 to $35^{\circ}C$. On the whole, the best protocol called for Ganoderma neo-japonicum transfer onto media containing Congo red with a pH of 7.0, followed by incubation at $25^{\circ}C$ for 5 days. Our results will be useful to researchers who study extracellular enzyme activity in Ganoderma neo-japonicum.