• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2110-2115
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• 2015

A liquid-based colorimetric assay using a pH indicator was introduced for high-throughput monitoring of lysine decarboxylase activity. The assay is based on the color change of bromocresol purple, measured at 595 nm in liquid reaction mixture, due to an increase of pH by the production of cadaverine. Bromocresol purple was selected as the indicator because it has higher sensitivity than bromothymol blue and pheonol red within a broad range and shows good linearity within the applied pH. We applied this for simple determination of lysine decarboxylase reusability using 96-well plates, and optimization of conditions for enzyme overexpression with different concentrations of IPTG on lysine decarboxylase. This assay is expected to be applied for monitoring and quantifying the liquid-based enzyme reaction in biotransformation of decarboxylase in a high-throughput way.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3133-3136
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• 2011

• Advances in nano research
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• 제14권4호
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• pp.313-327
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• 2023

Zinc metal organic framework (MOF_Zn)-loaded goad nanoparticles (AuNPs) sol (Au@MOF_Zn), which was characterized by TEM, Mapping, FTIR, XRD, and molecular spectrum, was prepared conveniently by solvothermal method. The results indicated that Au@MOF_Zn had a very strong catalytic effect with the nanoreaction of AuNPs formation between sodium oxalate (SO) and HAuCl4. AuNPs in the new indicator reaction had a strong resonance Rayleigh scattering (RRS) signal at 370 nm. The indicator AuNPs generated by this reaction, which had the most intense surface enhanced Raman scattering (SERS) peak at 1621 cm -1. The new SERS/RRS indicator reaction in combination with specific aptamer (Apt) to fabricate a sensitive and selective Au@MOF_Zn catalytic amplification-aptamer SERS/RRS assay platform for carbendazim (CBZ), with SERS/RRS linear range of 0.025-0.5 ng/mL. The detection limit was 0.02 ng/mL. Similarly, this assay platform has been also utilized to detect oxytetracycline (OTC) and profenofos (PF).

• Clinical and Experimental Reproductive Medicine
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• 제20권1호
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• pp.1-7
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• 1993

The present study was designed to test the validity of the semen analysis(S/A) and the sperm penetration assay(SPA) as a prognostic indicator of male fertility in 123 patients undergoing in vitro fertilization(IVF). We attempted to correlate the traditional semen parameters or the extent of sperm penetration in SPA with the results of human IVF rate or cleavage rate. Poor correlation was found between the results of S/A and human IVF rate(sensitivity, 80.6% ;specificity, 46.7%; positive predictive value, 91.6%;negative predictive value, 25%). Conversely, good correlation was found between the results of SPA and human IVF rate(sensitivity, 100% ; specificity, 80% ;positive predictive value, 97.3% ;negative predictive value, 100%). Our results corroborate the conclusion that SPA can be a valuable tool as a prognostic indicator of male fertilizing ability.

• Environmental Engineering Research
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• 제25권2호
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• pp.197-204
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• 2020

A number of different nanoscale zero-valent iron (nZVI) materials have been prepared and compared depending on the desired properties for the particular application, but different physicochemical properties of this prepared nZVI make it difficult to universally compare and standardize them to the same scale. In this study, we aimed to demonstrate a simple microplate-based colorimetric assay using 4-chlorophenol as an indicator with respect to the remediation of real treatment targets, such as trichloroethylene (TCE), 1,1,1-trichloroethane (TCA), and atrazine. Effect of nickel contents on 4-chlorophenol reduction was successfully investigated by the miniaturized colorimetric assay. In the same manner, the effect of nickel contents on dehalogenation of TCE, TCA, and atrazine was investigated and the pseudo-first-order kinetic constants were compared with the results for 4-chlorophenol. The similar pattern could be observed between 4-chlorophenol reduction obtained by colorimetric assay and TCE, TCA, atrazine reduction obtained by a traditional chromatographic method. The reaction kinetics does not match perfectly, but the degree of reaction can be estimated. Therefore, the colorimetric assay can be a useful and simple screening tool to determine nZVI reactivity toward halogenated organics before it is applied to a particular remediation site.

• 한국양식학회지
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• 제16권3호
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• pp.196-201
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• 2003

Sessile organisms such as the oyster Crassostrea gigas have been given much attention as a potential biomonitoring indicator to assess the impact of toxicants on aquatic organism. In this study, we exposed cells isolated from gill of oyster (Crassostrea gigas) to hydrogen peroxide in vitro. In addition oysters were in vivo exposed to pyrene and benzo(a)pyrene at various concentrations for 2 weeks. Comet assay was used to detect DNA single strand breaks and to investigate the application of this technique as a tool for aquatic biomonitoring. Hydrogen peroxide increased DNA single strand break with increasing concentration after 30 minutes exposure in vitro. Pyrene and benzo(a)pyrene caused DNA damage only at very high concentration (100 $\mu\textrm{g}$/L or 1000 $\mu\textrm{g}$/L) at two week exposure in vivo. DNA damage was relatively higher at hemocyte than at gill. It suggested that metabolized PAHs are transferred to hemolymph from digestive gland which have a relatively high enzyme activity, and attacked the DNA of hemocyte, while gill accumulated PAHs without degrading them to their metabolites due to low enzyme activity at gill. Both in vitro and in vivo exposure experiments showed that the comet assay is an effective tool on screening whether the organism are exposed to genotoxic contaminants.

• 미생물학회지
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• 제27권3호
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• pp.310-315
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• 1989

식물의 잎에 세균성 정무늬병을 야기시키는 식울 병원성균인 Pseudomonas syringae pv. tuhaci는 tabtoxin 이라는 phytotoxin 을 생성하는데 이 toxin을 미생물학적으로 간편하게 검색하는 방법플 여러가지 지시균주를 사용하여 각족 배지에서 검토하였다. Minimal A agar medium에서는 tabtoxin 검색에 Agrobactcrium tumefaces가 가장 유용한 균주였으며 minimal glucose agar m$\varepsilon$dium 에서도 역시 마찬가시의 견과를 얻였다 Complex agar medium 에서는 사용된 모든 지시균주에 대해 증식저지환이 형성되지 않아, tabtoxin이 생성되지 않음알수 있었다. 배양온도에 따른 tabtox의 생성능은 $20^{\circ}C$ 빛 $30^{\circ}C$ 에서 최적이였으며 배양시간이 경과함에 따라 tabtoxin 생성량이 증가 하였다. Glutamine을 minimal glucose agar medium에 첨가하여 tabtoxin 에 대한 지시 균주의 반응은 첨 가한 glutamine 의 양이 증가할수록 tabtoxin에 의한 생육억제가 감소함을 알 수 있었다.

• Journal of Nutrition and Health
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• 제49권5호
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• pp.277-287
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• 2016

본 연구는 제5기 2차년도 국민건강영양조사 결과를 활용하여 한식 식품군의 총 페놀 함량, in vitro 항산화활성 및 인체세포를 이용한 ex vivo DNA 손상 감소효과를 비교하고, 각 지표간의 상관성을 분석하며, 한식의 총 식사 항산화능에 대한 각 식품군의 기여도를 알아보기 위해 수행되었다. 제5기 2차년도 국민건강영양조사 결과를 바탕으로 한식의 식물성 식품을 10가지 식품군 (곡류, 과일류, 채소류, 견과류, 김치류, 해조류, 감자류, 버섯류, 두류, 오일류)으로 분류한 후 각 식품군별로 총 섭취량의 1% 이상 섭취한 식품 84종을 한식의 식물성 식품으로 최종 선정하였다. 각 식품군의 총 페놀함량을 측정하였고, DPPH radical scavenging assay, TEAC assay, $ORAC_{ROO{\cdot}}$ assay를 사용하여 in vitro 항산화능을 측정하였다. 한식의 식품군별 항산화능 (dietary antioxidant capacity, DAC)은 in vitro 항산화활성 평균값과 각 식품군의 1일 섭취량을 고려하여 계산하였고 한식 TDAC는 각 식품군의 DAC로의 합으로 구하였으며, TDAC에 대한 각 식품군 항산화능의 기여도를 평가하였다. 인체 임파구에서의 ex vivo DNA 손상 정도는 comet assay를 사용하여 평가하였다. 한식 식품군의 총 페놀함량은 버섯류, 과일류, 채소류, 해조류, 김치류 등의 순으로 높았으며, 3가지 in vitro 실험법을 평균한 식품군의 항산화활성 순위는 버섯류, 해조류, 채소류, 김치류, 과일류 등의 순이었다. 각 식품군의 항산화활성에 식품섭취량을 고려하여 계산한 한식의 TDAC에 대한 식품군의 항산화능 기여도는 곡류가 33.4%로 가장 높았으며, 과일류 (23.9%), 채소류 (12.7%), 김치류 (11.2%) 등의 순으로 나타났다. 인체 임파구에서 ex vivo DNA 손상 보호효과는 버섯류에서 가장 높았으며, 그 다음 채소류, 과일류, 해조류, 김치류의 순으로 나타났다. 각 식품군의 페놀함량과 in vitro 항산화 활성, 그리고 ex vivo DNA 보호효과의 순위가 비슷하게 나타났으며 각 지표간의 상관성은 매우 높았다. 한식 식품군 중 버섯류, 과일류, 채소류, 해조류에서 총 페놀함량과 항산화 활성, DNA 손상 보호효과가 높게 나타났다. 각 식품군의 총 페놀함량과 in vitro 항산화 활성, ex vivo DNA 보호효과 지표 간의 상관성은 매우 높았다. 한식의 TDAC에 대한 식품군별 항산화능 기여도는 곡류가 가장 높았고, 그 다음이 과일류, 채소류, 김치류의 순이었다. 이러한 결과는 앞으로 한식의 우수성을 항산화 측면에서 밝히는데 매우 중요한 기초자료로 활용될 수 있을 것이다.

• 한국유기농업학회:학술대회논문집
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• 한국유기농학회 2009년도 하반기 학술대회
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• pp.316-316
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• 2009

This study was conducted to investigate the effects of environment-friendly materials on garlic cultivation, and the methods for processing garlic at proper ripening stage to increase its antioxidant properties and market value. The functional properties of garlic and processed black garlic were analyzed in vitro and ex vivo. The ethanol extracts of garlic and black garlic were used in the antioxidant, linoleic acid autooxidation, lipid oxidation and RAW264.7 indicator cell using NO induced activity analyses. Also, toxicity tests by RBL-2H3 and RAW264.7 indicator cell using MTT assay were compared. Obesity inhibition test of garlic and black garlic were also studied.

• Journal of Microbiology and Biotechnology
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• 제16권9호
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• pp.1384-1391
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• 2006

The signal transduction system is one of the most important devices involved in maintaining life, and many protein kinases are included in the cellular signal transduction system. Finding a protein kinase inhibitor is very valuable, as it can be used to study cell biology and applied to pharmaceuticals. For the efficient and rapid screening of protein kinase inhibitors, two assay systems were combined; the nonradioactive protein kinase assay system that uses an FITC-labeled IRS-2 peptide and the cell-based paper disc assay system that uses Streptomyces griseus as the indicator strain. Among 330 kinds of herb extracts tested, the extract of Dalbergia odorifera exhibited the strongest inhibitory activity in the two assay systems and was selected for further isolation. Based on solvent extraction and many steps of chromatography, seven compounds were finally separated to homogeneity and their structures determined by $^{1}H$ and $^{13}C$ NMR spectroscopies. Four were to be flavonoids and identified as butin ($C_{15}H_{12}O_5$, Mw=272.07), 3'-hydroxymelanetin ($C_{16}H_{12}O_6$, Mw=300.06), liquiritigenin ($C_{15}H_{12}O_4$, Mw=256.07), and 2'-hydroxyformononetin ($C_{16}H_{12}O_{5}$, Mw=284.07). 3'-Hydroxymelanetin inhibited the phosphorylation of the GSK3 protein by Akt to 37% at a concentration of $10{\mu}g/ml$ and showed the strongest cytotoxicity ($ED_{50}<50{\mu}g/ml$) against the human cancer cell line HCT116. Under the same conditions, liquiritigenin also inhibited the phosphorylation of GSK3 by Akt to 26%, and its cytotoxicity against the HCT116 cell line was lower than $100{\mu}g/ml$.