• 한국해양생명과학회지
• /
• 제1권2호
• /
• pp.79-87
• /
• 2016

카드뮴과 같은 중금속은 독성이 높아 수서 생물과 인간에게 해로운 영향을 미친다고 알려져 있다. 본 연구에서는 해양 섬모충 Euplotes crassus에서 카드뮴이 해독 기전에 관여하는 ABC transporters (ABCs)와 glutathione S-transferase (GST)의 유전자 발현에 미치는 영향을 조사하였다. 총 7개의 ABCs 유전자와 1개의 GST 유전자 일부를 클로닝하여 유전자 분석을 실시하였고, 카드뮴(0.1~1 mg/l) 노출에 따른 이들 유전자의 발현 양상을 quantitative real time RT-PCR (qRT-PCR)을 이용하여 분석하였다. 염기서열 분석과 계통 분석 결과 이들 ABCs 유전자가 ABC transporter의 특징을 가지며, ABC-B/C family에 속하는 것을 확인하였고, GST 유전자는 theta isoform과 유사한 것으로 나타났다. 카드뮴에 8시간 노출시킨 결과 ABC transporter 유전자의 경우 ABCB21 유전자를 제외하고는 대부분 농도 의존적으로 유전자 발현이 유의하게 증가하였다. GST 유전자는 0.5 mg/l에서 가장 높은 유전자 발현 양상을 보였으며, 1 mg/l에서는 발현량이 대조군 수준으로 감소되었다. 본 연구 결과는 E. crassus의 ABC transporter와 GST 유전자가 카드뮴에 의해 유도되는 독성에 대한 방어 기전에 참여하는 것을 의미한다.

• 해양환경안전학회지
• /
• 제28권1호
• /
• pp.1-9
• /
• 2022

본 연구에서는 폐기물 배출해역의 퇴적물이 해양생물에 미치는 영향을 평가하기 위해 2016~2019년 3개 배출해역; 동해병, 서해병, 동해정 해역의 9개 정점에서 채취한 퇴적물 시료들을 대상으로 국내 해양폐기물공정시험기준에 의거하여 저서성단각류(Monocorophium acherusicum)와 발광박테리아(Vibrio fischeri)를 이용한 독성시험을 수행하였다. 시험결과, 상대평균생존율(저서성단각류)과 상대발광저해율(발광박테리아)이 각각 30 % 이하로서 '독성없음'으로 판정되었으나, t검정을 이용한 독성 평가 결과에서는 총 12개(2016년 6개, 2017년 1개, 2018년 1개, 2019년 4개)의 저서성단각류 시료에서 대조구와 유의한 차이를 나타내었다(p<0.05). 저서성단각류의 독성원인 탐색을 위해 퇴적물 내 8종 중금속 함량(Cr, As, Ni, Cd, Cu, Pb, Zn, Hg)과 저서성단각류 상대평균생존율의 단순선형회귀분석을 수행한 결과, Cr의 저서성단각류 독성 기여도가 가장 높았다(p=0.000, R²=0.355). 또한, 매년 독성영향이 가장 높은 정점(DB-85)의 시료에서 Cr이 여전히 가장 높은 농도로 검출되었으며, 해양환경기준을 매년 초과하였다. 해양폐기물공정시험기준의 생태독성판정 기준 적용 시 '독성없음'으로 평가되는 퇴적물 오염도가 대조구와의 통계적 유의성 검정, 독성원인확인 평가를 적용할 경우 독성영향을 수용 가능한 수준으로 판단하기 어려우므로 향후 종민감도분포곡선을 활용한 정량적 위해성 평가를 통한 준거치를 도출하여 생태독성 영향 판단 기준의 재설정을 고려할 필요가 있다.

• Journal of the korean society of oceanography
• /
• 제39권3호
• /
• pp.186-196
• /
• 2004

Since seagrasses are highly productive and provide a source of organic carbon for a wide variety of marine organisms in coastal and estuarine ecosystem, accurate assessment of seagrass production is critical to understand the functions and values of seagrasses in these ecosystems. Zieman's leaf marking technique has been mostly used to estimate seagrass leaf production rates. However, inherent problems on the traditional leaf marking technique have been discussed by the several researchers, and these problems can cause underestimation of seagrass production. To develop an accurate and reliable assessing method for seagrass production, production rates of eelgrass, Zostera marina in three bay systems on the south coast of the Korean peninsula were estimated using the conventional leaf marking technique and the plastochrone method. The plastochrone method has been recently suggested as an effective method for reliable assessments of seagrass production. In the present study, leaf production rates estimated by the plastochrone method were significantly higher than the rates derived from the traditional leaf marking technique. Annual eelgrass leaf production assessed using the leaf marking technique was about 65 to 89% of the estimated production using the plastochrone method. The differences in annual productions between assessment techniques imply that the conventional leaf marking technique significantly underestimated eelgrass leaf production. Total eelgrass productions estimated using the plastochrone method in the present study sites were about 600 to 806 g DW $m^{-2} y^{-l}$, and below-ground production accounted for about 20 to 23% of the total production. The plastochrone method was suggested to be an effective and accurate assessing method for eelgrass production.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권10호
• /
• pp.1461-1476
• /
• 2009

This review focuses on the metabolic and osmoregulatory functions of betaine and its impact on nutrient digestibility and performance in pigs and poultry. Betaine is the trimethyl derivative of the amino acid glycine, and is present in plant and animal tissue. It has been shown to play an important role in osmoregulation of plants, bacteria and marine organisms. Due to its chemical structure, betaine exerts a number of functions both at the gastrointestinal and metabolic level. As a methyl group donor, betaine is involved in transmethylation reactions and donates its labile methyl group for the synthesis of several metabolically active substances such as creatine and carnitine. Therefore, supplementation of betaine may reduce the requirement for other methyl group donors such as methionine and choline. Beneficial effects on intestinal cells and intestinal microbes have been reported following betaine supplementation to diets for pigs and poultry, which have been attributed to the osmotic properties of betaine. Furthermore, betaine potentially enhances the digestibility of specific nutrients, in particular fiber and minerals. Moreover, at the metabolic level, betaine is involved in protein and energy metabolism. Growth trials revealed positive effects of supplemental betaine on growth performance in pigs and poultry, and there is evidence that betaine acts as a carcass modifier by reducing the carcass fat content. In conclusion, due to its various metabolic and osmoregulatory functions, betaine plays an important role in the nutrition of monogastric animals.

• 한국발생생물학회지:발생과생식
• /
• 제15권4호
• /
• pp.359-364
• /
• 2011

The seven selected primers OPA-02, OPA-04, OPA-18, OPD-07, OPD-08, OPD-15 and OPD-16 were used to generate unique shared loci to each species and shared loci by the two species. The hierarchical dendrogram indicates three main branches: cluster 1 (RORETZI 01~RORETZI 11) and cluster 2 (HILGENDORF 12~HILGENDORF 22) from two geographic populations of ascidians, Halocynthia roretzi and H. hilgendorfi. The shortest genetic distance displaying significant molecular difference was between individuals' HILGENDORF no. 14~HILGENDORF no. 19 (genetic distance =0.008). Ultimately, individual no. 02 of the RORETZI ascidian was most distantly related to HILGENDORF no. 21 (genetic distance=0.781). These results demonstrate that the H. roretzi population is genetically different from the H. hilgendorfi population. From what has been said above, the potential of PCR analysis to identify diagnostic markers for the identification of two ascidian populations has been demonstrated. Generally speaking, using a variety of decamer primers, this PCR method has been applied to identify specific markers particular to line, species and geographical population, as well as genetic diversity/polymorphism in diverse species of organisms.

• Ocean and Polar Research
• /
• 제25권2호
• /
• pp.147-154
• /
• 2003

To develop fast and sensitive biomarkers for metal exposures in Antarctic marine organisms we examined histological alterations of an Antarctic sentinel bivalve species Laternula elliptica following a short-term exposure to a sublethal-level of Cd. Distinct histological alterations of tissues and cells of the gills, kidneys, and digestive glands were observed after 8-to 16-hours of exposure to Cd while an increase of Cd concentrations in tissues was not detectable. Most alterations were highly localized in the epithelium of the three tissues; epithelia were found to be detached from the remaining tissue parts. In addition ultra-structural changes such as cytosolic vacuolization, dilation of nucleus and rER membranes were detected in all three tissues, which suggested that the clams are subject to sublethal stresses. Thus, histological and ultrastructural changes on localized tissue parts were rapid and sensitive, suggesting that they may serve biomarkers for Cd exposures. Linkages between the shown ulrastructural changes and higher biological organization level responses are to be established by longer-term exposure experiments.

• 한국수산과학회지
• /
• 제12권2호
• /
• pp.119-123
• /
• 1979

남해안산 방어와 돌돔에 대한 수은, 구리 및 카드뮴의 중금속독성 실험을 1978년 7월 18일$\~$27일간 정수식으로 실험실에서 실시하였다. 실험결과 24시간 반수치사농도(24hr-LC50)는 방어에 있어서는 수은이 0.10mg/l, 카드뮴 0.82mg/l, 구리 1.03 mg/l였고, 돌돔에 있어서는 수은 1.61mg/l, 구리 1.73mg/l를 나타냄으로서 중금속별 독성 순위는 방어는 수은, 카드뮴 구리이고 돌돔은 수은-구리-카드뮴 순이며 도종류 공히 수은 독성이 가장 강함을 구명하였다.

• Journal of Species Research
• /
• 제5권3호
• /
• pp.517-529
• /
• 2016

Two scale worms of the family Polynoidae, Arctonoe vittata (Grube, 1855) and Hyperhalosydna striata (Kingberg, 1856) were found for the first time from Korea by SCUBA diving survey. The two species are free-living organisms or associated commensally with a wide variety of other invertebrates. Specimens of A. vittata were collected from the East Sea and were closely associated with asteroids, holothuroids, gastropods and nudibranchs species. Specimens of H. striata were collected from Jeju-do Island, and of these, one specimen was collected in a tube of eunicid species. The two species can be easily distinguished from their congeners by distinct morphological characteristics as follows: (1) A. vittata has pigmented band near segment eight and two kinds of neurochaetae; (2) H. striata has reddish-brown longitudinal striped elytra. The morphological key characteristics of both species agreed well with their original descriptions and redescriptions. In this study, the descriptions, detailed illustrations and ecological photographs of two species based on Korean materials were provided.

• 한국패류학회지
• /
• 제21권1호
• /
• pp.19-24
• /
• 2005

This study was undertaken with the intent to describe the influence of water temperature and food concentration on the filtration rates of the Asiatic clam, Corbicula fluminea. The clams were collected at Lake Geumho near Yeongsan river, during March 2001. Food organism, Scenedesmus sp. (KMCC FC-34), was indoor-cultured in f/2 medium, and was used to measure the filtration rate of the clams. Filtration rate of the clams was measured by indirect method. Cell concentrations of food organisms were determined by direct counting cells using the hemacytometer under the light microscope. The filtration rate of the clams increased with water temperature up to circa $25^{\circ}C$. Above this temperature, the filtration rate decreased rapidly. The minimal filtration rate of the clams was recorded at $5^{\circ}C$. Thermal coefficient, $Q_10$ values at low temperature range were much higher than those at high temperature range. These results indicate the asiatic clam is more sensitive in cold water like most of marine bivalves. There was a strong reversed correlation between filtration rate and food concentration. Filtration rate of the clams was reduced as food concentration was increased.

• 한국환경과학회지
• /
• 제26권5호
• /
• pp.639-649
• /
• 2017

Measurements of polychlorinated biphenyls (PCBs) were taken in surface sediments inside Seogwipo and Hallim Harbors of Jeju Island, Korea, to evaluate their distribution. These harbors typically have heavy ship traffic. The samples were collected three times (in June, October, and December, 2013). PCB concentrations in sediments from Seogwipo Harbor were higher than in those from Hallim Harbor, but both levels were very low, compared with those in other parts of the world. Sedimentary PCB levels had a strong correlation with organic carbon and fine granule mud content. PCB concentration values in the examined surface sediments were much lower than Sediment Quality Guidelines (SQGs) such as ER-L (Effect Rrange-Low), TEL (Threshold Effects Level) and ISQG (Interim Sediment Quality Guideline)-low value applied in countries, such as USA, Canada, and Australia. This suggests that the PCBs did not have significant biological effects on benthic organisms in the marine environment.