• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.122-127
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• 2007

In this study, an analytical method was optimized for detecting dioxin-like PCBs in fish and shellfish. Here, homogenized samples were extracted using an accelerated solvent extraction (ASE) system with 33 mL cell size. Multilayer column chromatography, which consisted of acidic, basic and neutral silica gels, was used for the clean up of the extracts. The instrumental analysis was executed by HRGC/HRMS to a resolution of 10,000 using 4 window multiple ion detection (MID) mode. For the results, the average recoveries ranged from 94.1 to 104.1% (${\pm}8.4$) and the limit of detection was approximately 0.1 pg/g at S/N ratio >3. Finally, the detected concentrations of dioxin-like PCBs for fish and shellfish were in the range of 0.030-1.836 pg TEQ/g.

• Korean Journal of Remote Sensing
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• v.30 no.3
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• pp.351-366
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• 2014

The aim of this study was to develop software for beach litter detection that includes a Graphical User Interface (GUI) and uses images taken by a micro-unmanned aerial vehicle. Videos were taken over Doomo pebble beach, Sogye pebble beach, and Heungnam sand beach on the northeast coast of Geojedo (Geoje Island), Korea. Still images of actual beach litter were obtained from the videos. The image processing involved preprocessing, morphological image processing, and image recognition. Comparison with still images showing beach litter demonstrated that the software could generally detect litter larger than 50 cm in size such as Styrofoam buoys and circular fish traps (excluding small pixel-size ropes). Combining the proposed method with the conventional surveying approach is expected to enhance the accuracy of beach litter detection. The new technique will also aid in predicting the amount of beach litter generated along coastlines, which is currently difficult to monitor.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1154-1158
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• 2004

The classical ABC (avidin-biotin peroxidase complex) method for immunohistochemistry in the paraffin-embedded tissues bring into being disadvantage such as low sensitivity of antigen detection and highly background. The biotinyl-tyramide conjugation recently introduced for sensitive immunohistochemistry was applied to light microscopy in paraffin-embedded pancreatic and liver tissues. The protocol consists of an indirect method in which 4-5㎛ tissue sections are reacted successively within a specific primary antibody, followed by a biotinylated secondary antibody, streptavidin-horseradich peroxidase (HRP), and then finally with biotinyl-tyramide. The labeling obtained for insulin and collagen antigen tested in pancreatic and liver tissues, respectively, was found to be highly specific with the labeling for each antigen confined to its particular cellular compartment. In this study, fish (flounder) serum was specially applied to remove nonspecific binding. Background levels and nospecific deposition of the staining were negligible. This results suggest that super-signal induction method by biotinyl-tyramide conjugate can readily applied to antigen detection of the paraffin-embedded tissues.

• Culinary science and hospitality research
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• v.24 no.2
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• pp.119-127
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• 2018

The purpose of this study is to investigate the contamination level of micro plastics in Korean mackerel and to investigate the detection method of micro plastics in fish. This study analyzed the detection and composition of micro plastics using natural mackerel and wild mackerel. 30% hydrogen peroxide and surfactant were added to GF/C filter paper in order to detect micro plastics in the sea. If micro plastics are exposed to the ocean for a long time, accumulation of heavy metals in the water will make pollutant bioaccumulation more serious. Microscopic consequences The risk to human health of plastics has already been studied by many researchers and the risks to human health already caused by marine microorganisms and zooplankton are becoming clear. The conclusion of this study is that there is a difference between the length and height of the mackerel when it is cooked from the standpoint of food in terms of practical implications. The conclusion of this study is that the probability of micro-plastic-contaminated mackerel to reach and be consumed by end-consumers is low in academic implications. Residual contaminants adsorbed on micro plastics are absorbed by digestive organs and cause disruption, and further research on micro plastics is needed in the future.

• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1742-1746
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• 2008

Catechol and caffeine were simultaneously analyzed with a bismuth-immobilized carbon nanotube paste electrode (BPE) using square wave (SW) stripping voltammetry. Optimum analytical conditions were determined. Simultaneous working ranges of 100-1,500 $mgL^{-1}$ for caffeine and 5-75 $mgL^{-1}$ for catechol were obtained. In the separated cell systems, a working range of 0.1-2.1 $mgL^{-1}$ catechol with a correlation coefficient of 0.9935, and a working range of 10-210 $mgL^{-1}$ caffeine with a correlation coefficient of 0.9921 were obtained. A detection limit (S/N) of 0.15 $mgL^{-1}$ (7.7 ${\times}$ $10^{-7}$ M) and a detection limit of 0.02 $mgL^{-1}$ (1.82 ${\times}$ $10^{-7}$ M), respectively, manifested for catechol and caffeine. It was found that three macro-type electrode systems could be implanted in fish and rat neuro cells. For both ions, the ion currents were observed. The physiological impulse conditions and the neuronal thinking current were also obtained.

• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1355-1363
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• 2018

Many radionuclides exist in normal environment and artificial radionuclides also can be detected. The radionuclides ($^{131}I$) are widely used for labeling compounds and radiation therapy. In Korea, the radionuclide ($^{131}I$) is produced at the Radioisotope Production Facility (RIPF) at the Korea Atomic Energy Research Institute in Daejeon. The residents around the RIPF assume that $^{131}I$ detected in environmental samples is produced from RIPF. To ensure the safety of the residents, the radioactive concentration of $^{131}I$ near the RIPF was investigated by monitoring environmental samples along the Gap River. The selected geographical places are near the nuclear installation, another possible location for $^{131}I$ detection, and downstream of the Gap River. The first selected places are the "front gate of KAERI", and the "Donghwa bridge". The second selected place is the sewage treatment plant. Therefore, the Wonchon bridge is selected for the upstream of the plant and the sewage treatment plant is selected for the downstream of the plant. The last selected places are the downstream where the two paths converged, which is Yongshin bridge (in front of the cogeneration plant). In these places, environmental samples, including sediment, fish, surface water, and aquatic plants, were collected. In this study, the radioactive iodine ($^{131}I$) detection along the Gap River will be investigated.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.2
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• pp.80-86
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• 2022

The ability to determine the sex of bovine embryos before the transfer is advantageous in livestock management, especially in dairy production, where female calves are preferred in milk industry. The milk production of female and male cattle benefits both the dairy and beef industries. Pre-implantation sexing of embryos also helps with embryo transfer success. There are two approaches for sexing bovine embryos in farm animals: invasive and non-invasive. A non-invasive method of embryo sexing retains the embryo's autonomy and, as a result, is less likely to impair the embryo's ability to move and implant successfully. There are lists of non-invasive embryo sexing such as; Detection of H-Y antigens, X-linked enzymes, and sexing based on embryo cleavage and development. Since it protects the embryo's autonomy, the non-invasive procedure is considered to be the safest. Invasive methods affect an embryo's integrity and are likely to damage the embryo's chances of successful transformation. There are different types of invasive methods such as polymerase chain reaction, detection of male chromatin Y chromosome-specific DNA probes, Loop-mediated isothermal amplification (LAMP), cytological karyotyping, and immunofluorescence (FISH). The PCR approach is highly sensitive, precise, and effective as compared to invasive methods of farm animal embryonic sexing. Invasive procedures, such as cytological karyotyping, have high accuracy but are impractical in the field due to embryonic effectiveness concerns. This technology can be applicable especially in the dairy and beef industry by producing female and male animals respectively. Enhancing selection accuracy and decreasing the multiple ovulation embryo transfer costs.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.1
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• pp.36-40
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• 2010

Ballast water has been known as a major vector for global dispersal of toxic dinoflagellates and other microalgae. In this study, biodiversity in ships’ ballast water was examined using a dinoflagellate-oriented PCR primer set and species-specific real-time PCR. While motile dinoflagellates could be observe at very low cell densities by light microscopy,a wide range of dinoflagellate taxa including parasitic and phototrophic pico-dinoflagellates as well as harmful species to marine fish/shellfish was detected when techniques for cloning/sequencing of SSU rDNA of sample cells were used. Present result suggests that molecular methods including species-specific PCR primers may offer rapid and accurate detection of invasive species in ballast water.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.882-888
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• 2005

Procedure for analysis of methylmercury in fish was developed, involving addition of HCl, extraction with toluene, and clean-up using L-cystein solution. Obtained extract is analyzed by gas chromatography with electron capture detector using Ulbon HR-Thermon-Hg column. Detection limit and recovery of the method were 0.005mg/kg (expressed as Hg), 98-107 (103%), respectively. Total mercury and methylmercury concentrations in 175 commercial fish samples ranged from [mean-max (mean), unit: mg/kg]: 0.014-1.200 (0.270) and 0.006-0.901 (0.168) in tuna-fish, 0.020-0.934 (0.323) and 0.012-0.553 (0.149) in martin-fish, 0.082-0.782 (0.391) and 0.040-0.436(0.201) in shark, 0,023-0.031 (0.026) and 0,013-0.018 (0.015) in salmon, 0.098-0.193 (0.133) and 0.031-0.015(0.090) in tilefish, and 0,031-0.214 (0.089) and 0.016-0.093 (0.042) in canned tuna respectively. No sample of analyzed fish exceeded 1.0mg/kg wet wt., limit for methylmercury established by Codex. In all species examined, estimated weekly intake was lower than Provisional Tolerable Weekly Intake recommended by the JECFA (the Joint FAO/WHO Expert Committee on Food Additives).

• Journal of fish pathology
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• v.22 no.3
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• pp.335-342
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• 2009

The stability of immunoglobulin M (IgM) on different serum storage conditions and specific antibody response were tested using the serum collected from sevenband grouper Epinephelus septemfasciatus by enzyme-linked immunosorbent assay (ELISA). To test the effect of storage temperature and duration, sevenband grouper antiserum against bovine serum albumin (BSA) was stored at -80, -20 or 4${^{\circ}C}$ for 1, 34, 61 or 119 days. In addition, to test the effect of repeated freeze-thawing condition, the anti-BSA fish serum was frozen at -20 and -80${^{\circ}C}$ and then thawn and frozen for 1, 5 or 10 times repeatedly. Consequently, no significant difference was found in ELISA optical density (O.D.) values of sera for the above mentioned storage conditions: different temperatures (-80, -20 and 4${^{\circ}C}$), durations of storage (1, 34, 61 and 119 days), and repeated thaw-freeze cycles (1, 5, and 10 times), indicating that IgMs of test fish were stable. The specific antibody response of sevenband grouper was observed after BSA-immunization of the test fish reared at 20 ${^{\circ}C}$ or 25${^{\circ}C}$. At the rearing temperature of 20${^{\circ}C}$, the specific antibody against BSA first appeared at 14 days and maximum antibody titer was observed between 21 and 28 days, while at the rearing temperature of 25 ${^{\circ}C}$, specific antibody appeared at 7 days and maximum antibody titer was observed between 14 and 21 days. In conclusion, the rearing temperature at 25${^{\circ}C}$ gave a faster and higher specific antibody response than at 20${^{\circ}C}$ and the specific antibody response maintained for approximately 2 months at 20℃ and 25${^{\circ}C}$.