• 환경생물
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• 제39권4호
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• pp.507-514
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• 2021

A new free-living marine nematode species of the genus Pseudosteineria Wieser, 1956 affiliated with the family Xyalidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Pseudosteineria varisetis sp. nov differed from its congeners by the combination of the following characteristics: a relatively long body (1,628-1,691 ㎛ long in males), a circular amphideal fovea situated behind the subcephalic setae, the presence of lateral cuticular alae starting from behind the nerve ring, the presence of eight groups of long subcephalic setae, the presence of irregularly distributed variable lengths of somatic setae on the body, solid spicules (43.2-43.9 ㎛ long) with a cephalated proximal end, a long tubular shaped gubernaculum with dorsal swelling, and a conico-cylindrical tail with two to four terminal setae. In this report, we provide a taxonomic description and illustrations of a new species of the genus Pseudosteineria by differential interference contrast microscopy.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.132-133
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• 2003

The marine dinoflagellate genus Alexandrium comprise PSP producing A. acatenella, A. angustitabuzatum, A. catenella, A. fundyense, A. minutum, A. ostenfezdii, A. tamiyavanichii and A. tamarense. In monitoring toxic Alexandrium, rapid and exact species identification is one of the significant prerequisite work, however we have suffered confusion of species definition in Alexandrium. To surmount this problem, we chose DNA probing, which has long been used as an alternative for conventional identification methods, primarily relying on morphological approaches using microscope in microbial field. Oligonucleotide DNA probes targeting rRNA or rDNA have been commonly used in diverse studies to detect and enumerate cells concerned as a culture-indetendent powerful tool. Despite of the massive literature on the HAB species containing Alexandrium, application of DNA probing for species identification and detection has been limited to a few documents. DNA probes of toxic A. tamarense, A. catenella and A. tamiyavanichii, and non-toxic A. affine, A. fraterculus, A. insuetum and A. pseudogonyaulax were designed from LSU rDNA D1-D2, and applied to whole cell-FISH. Each DNA probes reacted only the targeted Alexandrium cells with very high species-specificity within Alexandrium. The probes could detect each targeted cells obtained from the natural sea water samples without cross-reactivity. Labeling intensity varied in the growth stage, this showed that the contents of probe-targeted cellular rRNA decreased with reduced growth rate. Double probe TAMID2S1 achieved approximately two times higher fluorescent intensity than that with single probe TAMID2. This double probe did not cross-react with any kinds of microorganisms in the natural sea waters. Therefore we can say that in whole-cell FISH procedure this double DNA probe successfully labeled targeted A. tamiyavanichii without cross-reaction with congeners and diverse natural bio-communities.

• Animal Systematics, Evolution and Diversity
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• 제27권3호
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• pp.228-238
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• 2011

Two urostyloid ciliates, collected from brackish water in Korea, were identified as Diaxonella pseudorubra pseudorubra (Kaltenbach, 1960) Berger, 2006 and Pseudokeronopsis flava (Cohn, 1866) Wirnsberger, Larsen and Uhlig, 1987. The description was based on living, protargol impregnated specimens. These species are described as follows: Diaxonella pseudorubra pseudorubra: body size in vivo $145-230{\times}40-60\;{\mu}m$, elongated ellipsoidal in shape. Cytoplasm reddish and flexible. Adoral zone of membranelles occupied 30-40% of the body; composed of 33-44 membranelles; 1-3 frontoterminal cirri, 1-4 frontal row cirri, 4-6 buccal cirri, 6-10 transverse cirri. Midventral rows composed of 14-24 cirri, four left marginal rows, one right marginal row. Two kinds of cortical granules; the larger one is yellowish and the smaller one is reddish. Pseudokeronopsis flava: body size in vivo $150-210{\times}30-45\;{\mu}m$, elongated ellipsoidal shape. Cytoplasm yellowish and flexible. Adoral zone of membranelles occupied 25-30% of body; composed of 44-58 membranelles in number. Frontal cirri forming bicorona composed of 5-7 cirral pairs, 2-3 frontoterminal cirri, one buccal cirrus, and 2-3 transverse cirri. Midventral rows composed of 18-33 cirri, 34-53 left marginal cirri, and 40-58 right marginal cirri. Two kinds of cortical granules; the larger one is colorless and "blood-cell-shaped," and the smaller one is yellowish. Diaxonella pseudorubra pseudorubra is different from the most similar subspecies, D. pseudorubra pulchra, in cytoplasmic color and number of midventral cirri. Pseudokeronopsis flava is different from its most similar congeners in pigment granular color, number of bicorona, number of midventral cirri, and position of the contractile vacuole.

• 분석과학
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• 제28권6호
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• pp.446-452
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• 2015

본 숙련도 시험 프로그램은 ABS (acrylonitrile-butadiene-styrene) 수지 중 브롬계 난연제 PBDE들에 대한 국내 시험소들의 분석능력을 평가하고 향상시키기 위해 ISO/IEC 17043에 준하여 한국표준과학연구원(KRISS)이 수행하였다. 숙련도시험 물질은 PBDE류 (BDE-154, 183, 206, 209)가 첨가된 10 그램의 알갱이 형 ABS였으며 KRISS에서 균질성과 안정성을 확인한 후 사용되었다. KRISS에서는 확립한 국가 표준을 기반으로 숙련도시험 물질에 포함된 각 PBDE들의 인증값을 계산하였으며 숙련도 시험의 설정값으로 하였다. 숙련도 시험에는 16개 시험소들이 참여하였으며 측정방법은 각 시험소들이 서비스에 사용하는 일상적인 방법을 사용하도록 하였다. 참여 시험소들의 분석 능력을 평가하기 위해 ISO/IEC 17043의 z-score법을 사용하였으며 비밀보장을 위해 각 참여 시험소에 고유번호를 부여하였다. z-score는 이상치를 제외한 참여자들의 표준편차를 사용하여 계산하였다. 본 논문에서는 숙련도 시험의 결과, 참가 실험실 평가결과 그리고 숙련도시험을 통한 정확도 향상에 대하여 기술하였다.

• 한국환경보건학회지
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• 제42권2호
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• pp.102-111
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• 2016

Objectives: This study was conducted to evaluate the use of polyurethane foam disk passive air samplers (PUF PAS) for better measurement of atmospheric polychlorinared dibenzo-p-dioxins/furans (PCDD/Fs) concentrations compared to PUF PAS combined with high volume air samplers (HVS). Methods: Air samples were collected by a low volume air sampler (LVS) and PUF PAS. A total of two pairs were continuously collected for six months, but the PUF was replaced every two months. Results: A good correlation was shown ($R^2=0.8595$, p<0.0001) between atmospheric PCDD/Fs concentration measured by the LVS and PUF PAS. The average air sampling rate ($1.5m^3/day-sampler$) of all PCDD/Fs congeners showed a middle of the means which were measured using a HVS by other researchers in different cities. In addition, the air sampling rates of the LVS for each congener made less difference than did those of the HVS. Conclusion: It was found that measurements using the LVS were less influenced by atmospheric peak PCDD/Fs concentrations. However, trace POPs such as PCDD/Fs may involve relatively large analytical errors in measurement, and as a result the air sampling rate of the respective PCDD/Fs isomer is also likely to involve errors. The method of using a regression straight line between the concentrations obtained from the LVS and those from the PUF PAS was judged higher than the method using the air sampling rate, since the former compensated for the experimental errors in the process of evaluation of atmospheric PCDD/F concentrations using the PUF PAS.

• 한국환경보건학회지
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• 제36권2호
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• pp.118-127
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• 2010

Bivalve samples from 30 locations Korean coastal waters were analyzed to characterize the contamination with and distribution of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). The congeners of PBDE in 30 bivalve samples were analyzed by high resolution gas chromatography with a high resolution mass detector. The levels of PBDEs in bivalve samples ranged from 0.092 to 13.5 ng/g wet weight. These values for PBDEs concentrations in bivalves from Korea were higher than or comparable to available values for bivalves from other countries. In the congener profiles, BDE-47 (mean contribution=42.2%) was predominant, followed by BDE-99 (23.1%), BDE-100 (11.9%) and BDE-154 (3.5%). Among the OCs analyzed, $\Sigma$PCBs and $\Sigma$DDTs levels were highest, followed by $\Sigma$HCHs, $\Sigma$CHLs and HCB. The wet weight based $\Sigma$PCBs and $\Sigma$DDTs ranged from 0.28 ng/g to 19.4 ng/g, and from 0.19 ng/g to 4.86 ng/g, respectively. The $\Sigma$PCBs and $\Sigma$DDT slevels in bivalves along the entire Korean coast were lower than those of the USA, and below the Food and Drug Administration (USA. FDA) limits for fish and shell fish. However, the human health criteria and wild life criteria of the USA. Environmental Protection Agency (USA. EPA) were exceeded for DDE and $\Sigma$HCHs at most of the sampling points.

• 분석과학
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• 제24권6호
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• pp.435-442
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• 2011

폴리 브롬화 디페닐 에테르류(PBDEs)는 난연제의 한 종류로서 인체와 생태계에 영향을 미치는 잠재적인 독성물질이며 최근 들어 관심의 대상이 되고 있는 화학물질이다. 유럽연합을 비롯하여 많은 국가들은 전기전자제품에 이 물질의 사용을 제한하고 있다. 이와 관련된 시험소인정을 지원하기 위해 고충격 폴리스티렌(HIPS) 중 PBDE류 측정을 위한 숙련도시험을 ISO/IEC 17043을 기초로 하여 수행하였다. 고충격 폴리스티렌에 포함된 4종의 PBDE류(PBDE-154, 183, 206, 209)를 측정 대상 물질로 하여 숙련도시험이 수행되었다. 10 g의 펠렛형 고충격 폴리스티렌 시료를 35개 참가실험실들에게 배포하였고 실험실들의 능력을 평가하기 위해 z-score를 사용하였다. 숙련도 시험의 결과 및 참가 실험실 평가결과를 기술하였다.

• Toxicological Research
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• 제28권2호
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• pp.107-112
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• 2012

Polychlorinated biphenyls (PCBs) are persistent and bioaccumulative environmental pollutants. Recently, it is suggested that neurotoxic effects such as motor dysfunction and impairment in memory and learning have been associated with PCB exposure. However, structure relationship of PCB congeners with neurotoxic effects remains unknown. Since PKC signaling pathway is implicated in the modulation of motor behavior as well as learning and memory and the role of PKC are subspecies-specific, we attempted to study the effects of structurally distinct PCBs on the total PKC activity as well as subspecies of PKC in cerebellar granule cell culture model. Cells were exposed to 0, 25 and 50 ${\mu}M$ of PCB-126, PCB-169, PCB-114, PCB-157, PCB-52 and PCB-4 for 15 min. Cells were subsequently analyzed by [$^3H$] phorbol ester binding assay or immunoblotted against PKC-${\alpha}$ and -${\varepsilon}$ monoclonal antibodies. While non-dioxin-like-PCB (PCB-52 and PCB-4) induced a translocation of PKC-${\alpha}$ and -${\varepsilon}$ from cytosol to membrane fraction, dioxin-like PCBs (PCB-126, -169, -114, -157) had no effects. [$^3H$] Phorbol ester binding assay also revealed structure-dependent increase similar to translocation of PKC isozymes. While PCB-4 induced translocation of PKC-${\alpha}$ and -${\varepsilon}$ was inhibited by ROS inhibitor, the pattern of translocation was not affected in presence of AhR inhibitor. It is suggested that PCB-4-induced PKC activity may not be mediated via AhR-dependent pathway. Taken together, our findings suggest that chlorination of ortho-position in PCB may be a critical structural moiety associated with neurotoxic effects, which may be preferentially mediated via non-AhR-dependent pathway. Therefore, the present study may contribute to understanding the neurotoxic mechanism of PCBs as well as providing a basis for establishing a better neurotoxic assessment.

• Environmental Engineering Research
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• 제17권3호
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• pp.157-165
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• 2012

This experimental study was performed to obtain thermal energy from the combustion of synthetic gas, produced by the pyrolysis of insulating oil containing polychlorinated biphenyls (PCBs) in a high temperature and high pressure reactor. The average synthetic gas generated was $59.67Am^3/hr$ via the steady state gasification of insulating oil waste (20 kg/hr) with average concentrations (standard deviation) of $CO_2$, CO, and $H_2$ in the synthetic gas of $38.63{\pm}3.11%$, $35.18{\pm}1.93%$, and $28.42{\pm}1.68%$, respectively. The concentrations of the PCBs in the transformer insulating oil and synthetic gas after its gasification, and the concentrations of the dioxins that could be produced from the incomplete degradation of PCBs were measured. It was revealed that the PCBs in the insulating oil were composed of the series from tetrachlorobiphenyl to octachlorobiphenyl. However, only the #49, #44, #52, and #47/75/48 congeners were detected from the synthetic gas after gasification of the insulating oil and in the flue gas from the combustor. In conclusion, the experimental conditions suggested in this study were very useful for the appropriate treatment of insulating oil containing PCBs. Also, fuel gas containing CO and $H_2$ can be obtained from the pyrolysis of insulating oil containing PCBs.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.3.1-3.7
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• 2014

Objectives This study was conducted to determine the depositional characteristics of several tree barks, including Ginkgo (Ginkgo biloba), Pine (Pinus densiflora), Platanus (Platanus), and Metasequoia (Metasequoia glyptostroboides). These were used as passive air sampler (PAS) of atmospheric polybrominated diphenyl ethers (PBDEs). Methods Tree barks were sampled from the same site. PBDEs were analyzed by high-resolution gas chromatography/high-resolution mass spectrometer, and the lipid content was measured using the gravimetric method by n-hexane extraction. Results Gingko contained the highest lipid content (7.82 mg/g dry), whereas pine (4.85 mg/g dry), Platanus (3.61 mg/g dry), and Metasequoia (0.97 mg/g dry) had relatively lower content. The highest total PBDEs concentration was observed in Metasequoia (83,159.0 pg/g dry), followed by Ginkgo (53,538.4 pg/g dry), Pine (20,266.4 pg/g dry), and Platanus (12,572.0 pg/g dry). There were poor correlations between lipid content and total PBDE concentrations in tree barks ($R^2$=0.1011, p =0.682). Among the PBDE congeners, BDE 206, 207 and 209 were highly brominated PBDEs that are sorbed to particulates in ambient air, which accounted for 90.5% (84.3-95.6%) of the concentration and were therefore identified as the main PBDE congener. The concentrations of particulate PBDEs deposited on tree barks were dependent on morphological characteristics such as surface area or roughness of barks. Conclusions Therefore, when using the tree barks as the PAS of the atmospheric PBDEs, samples belonging to same tree species should be collected to reduce errors and to obtain reliable data.