• 한국환경과학회지
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• 제11권11호
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• pp.1157-1163
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• 2002

The effective removal of microcystins by chlorination was investigated on a laboratory scale. With an initial chl.a concentration of more than 1,000 $\mu\textrm{g}$/ℓ, the required chlorine dose for the effective removal of microcystins from the raw water was more than 8.0 mg/ℓ. Whereas, a chlorine dose of 3.0 mg/ℓcould effectively remove microcystins from raw water containing a chl.a concentration of less than 1,000 $\mu\textrm{g}$/ℓ. The microcystin removal was more effective below pH 8.0, plus the optimum pH range was unrelated to the concentration of toxic algal material. Although chlorination is one of the most effective methods for reducing the toxin from blue-green algae, it causes cell lysis and toxin release. However, it was demonstrated that the released cell lysates and toxins could be effectively removed by a higher dose of the oxidant. The highest removal efficiency of dissolved microcystins(initial concentration: 280 $\mu\textrm{g}$ L$\^$-1/) was with a chlorine dose of 5.0 mg/ℓ.

• 분석과학
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• 제13권3호
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• pp.399-402
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• 2000

To determine the concentrations of microcystins present in lake water or in tap water using high performance liquid chromatography, it is necessary to concentrate a large volume of water samples (about 20 L) into very small volume (0.1-0.3 mL). Concentration can be conveniently done when disc type solid phase extraction (SPE) apparatus is used. Using this apparatus we have investigated the recovery rates of three kinds of microcystins, RR, YR, LR. The recovery rates were relatively low and the reproducibilities were not good either. It is expected, however, that the appropriate selection of the disc conditioning and eluting solvents and reproducible reconcentration process after SPE will improve both the recovery rates and the reproducibilities.

• Bulletin of the Korean Chemical Society
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• 제32권1호
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• pp.149-152
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• 2011

A new chemiluminescence immunochromatographic analysis system with high sensitivity and high reproducibility was developed for the determination of microcystins (MCs) in water. Horse radish peroxidase (HRP) labeled microcystin monoclonal antibody was used for the sensitive chemiluminescence detection. The chemiluminescence immunochromatographic analysis system was composed of microcystin LR (MCLR)-monoclonal antibody (mAb)-Horse Radish Peroxidase (HRP) conjugate, MCLR-BSA conjugate, luminol, hydrogen peroxide mixture solution, an immunochromatographic assay strip and luminometer. To detect the concentration of microcystins in water, we utilized one spot analysis of the strip instead of flow type analysis. We could detect the microcystins in water at a concentration as low as 9.45 pg/mL with the chemiluminescence (CL) detection.

• Environmental Engineering Research
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• 제14권4호
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• pp.250-254
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• 2009

Contamination of microcystins, a family of heptapeptide hepatotoxins, in eutrophic water bodies is a worldwide problem. Due to their poisoning effects on animals and humans, there is a requirement to characterize and quantify all microcystins present in a sample. As microcystins are, for most part, intracellular toxins produced by some genera of cyanobacteria, lysing cyanobacterial cells to release all microcystins is considered an important step. To date, although many cell lysis methods have been used, little work has been conducted comparing the results of those different methods. In this study, various methods for cell lysis and toxin extraction from the cell lysates were investigated, including sonication, bead beating, freeze/thaw, lyophilization and lysing with TritonX-100 surfactant. It was found that lyophilization, followed by extraction with 75% methanol, was the most effective for extracting toxins from Microcystis aeruginosa cells. Another important step prior to the analysis is removing impurities and concentrating the target analyte. For these purposes, a C18 Sep-Pak solid phase extraction cartridge was used, with the percentage of the eluent methanol also evaluated. As a result, methanol percentages higher than 75% appeared to be the best eluting solvent in terms of microcystin-leucine-arginine (MC-LR) recovery efficiency for the further chromatographic and mass spectrometric analyses.

• 한국물환경학회지
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• 제25권5호
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• pp.720-726
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• 2009

We investigated the most effective pre-treatment processes and LC/MS/MS condition for microcystins analysis. With a step-by-step pre-treatment, efficiencies of several established methods were compared. At the level of cell burst, sonication method was found to be the most efficient. As a mycrocystins first extraction solvent, 5% acetic acid showed the highest efficiency. An isolation and recovery rate of mycrocystins of ODS Sep-Pak $C_{18}$ cartridge was higher than HLB SPE cartridge. As a final elution solvent from cartridge, 100% MeOH had a better efficiency than others. Using a LC/MS/MS, effective analytical methods were established. C18 reverse column was used and gradient elution was performed with using acetonitrile, 0.1% formic acid as a mobile phase. We analysed to 0.8 mL/min flow rate fit to the $5{\mu}m$ particle size column and $55^{\circ}C$ housing temperature. The validity of established analytical method was evaluated that MDL as average $0.050{\pm}0.014{\mu}g/L$ and LOQ as average $0.160{\pm}0.045{\mu}g/L$ had a good sensitivity over 40 magnification rather than $2{\mu}g/L$ detection limit of HPLC.

• 생태와환경
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• 제33권1호통권89호
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• pp.9-22
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• 2000

본 연구에서는 남조류의 독성물질 배출 및 분해양상을 밝히고자 대청댐 지류인 옥천천의 스컴을 채취, 실험대상으로 하였다. Light와 dark 상태로 분리${\cdot}$배양한 배지에는 조사를 하는 동안 다른 영양염류는 첨가하지 않았다. 그 결과 세포내에서 microcystins의 총량은 세포수가 감소함에 따라 감소하였으며 Microcystis aeruginosa의 현존량과 비교하였을 때 light와 dark 상태의 경우 $r^{2}$값이 각각 0.96과 0.97로 높은 상관관계를 보였고 dark 상태에서 보다 더 빠른 감소추세를 보였다. 또한 세포에서 수체로 용존되는 microcystins의 량은 세포내에 존재하는 양의 극히 일부임을 확인 할 수 있었고 세포내에 분포하는 microcystins의 농도는 종류에 따라 차이를 보여 microcystin-RR>-LR>-YR의 순으로 존재하는 것으로 나타났다. 이러한 결과는 옥정호과 제천천을 대상으로 한 수심별 조사에서도 동일한 양상을 보였다. 수체에서 검출된 microcystins의 양은 점성물질의 양과 함께 light와 dark 상태에 따라 뚜렷한 차이를 보였으며 light의 경우 $r^{2}$값이 -0.75의 역의 상관관계를 보였다. 남조류 세포 및 microcystins에 대한 light와 dark 상태에서의 서로 다른 농도 결과는 배양 상태에 따른 미생물의 분해양상의 차이와 미생물에 대한 점성물질의 영향으로 추정된다.

• 대한화학회지
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• 제46권6호
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• pp.535-540
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• 2002

남조류 독소인 마이크로시틴은 호수에서 매우 미량 존재하기 때문에 이를 정확히 정량 분석하기가 쉽지 않다. 본 연구에서는 소양호에서 채취한 물시료 중에 포함된 남조류 독소, 마이크로시틴을 정량 분석하기 위하여 두 가지 서로 다른 정량 분석법을 시도하였으며 이 둘의 정량 결과를 비교${\cdot}$분석 하였다. 첫째는 고체상 추출과 HPLC(High Performance Liquid Chromatography)를 이용한 분석법을 이용하였으며 둘째는 마이크로시틴의 단일클론항체를 이용한 효소면역흡착분석법(Enzyme-Linked Immunosorbent Assay,ELISA)을 이용하였다.

• 한국물환경학회지
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• 제27권4호
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• pp.491-498
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• 2011

We investigated the ranges of total cellular microcystins content of cyanobacterial blooms collected in Korean lakes and rivers from 2005 to 2009. The amount and composition of microcystins of Korean cyanobacteria varied depending on the sampling water bodies and dominant cyanobacterial genera. Toxic cyanobacterial cell numbers equivalent to $1{\mu}g$ MCYSTs/L using total cellular microcystin content of Korean cyanobacteria were in the range of 2,348 to 66,980,638 cells/mL. Only four samples among forty nine samples showed less cell numbers than current criterion of Harmful Algae Alert System, 5,000 cells/mL indicating current criterion do not reflect properly the microcystins content of Korean cyanobacteria. Anabaena and Aphanizomenon spp. showed three to six times higher cell numbers equivalent to $1{\mu}g$ MCYSTs/L than Microcystis spp. To propose criteria of Harmful Algae Alert System for Korean toxic cyanobacteria, we calculated about 50% selective geometrical means of cyanobacterial cell numbers equivalent to $1{\mu}g$ MCYSTs/L in order of toxic content. The proposed criteria for Microcystis, Oscillatoria, Anabaena, and Aphanizomenon spp., are 10,000, 20,000, 40,000, and 80,000 cells/mL, respectively.

• 한국생태학회:학술대회논문집
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• 한국생태학회 1998년도 춘계공동 학술발표대회
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• pp.42-42
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• 1998

• 대한화학회지
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• 제38권10호
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• pp.741-748
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• 1994

남조류의 독성물질인 microcystin을 HPLC로 분석하기 위해 지금까지는 ODS cartridge를 사용하였으나 본 연구에서는 CN cartridge를 사용하는 새로운 분석 방법을 시도하였다. CN cartridge는 0.5M 초산 용액으로 처리되었으며 Microcystins RR과 LR을 용리시키기 위해 30% Acetonitrile 용액이 사용되었다. CN cartridge를 이용하는 분석 방법이 기존의 ODS cartridge를 이용하는 방법보다 훨씬 더 정확한 정량을 할 수 있었다. 특히 Microcystin LR의 경우 피크 면적에서 현저한 차이를 보였다.