• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.3
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• pp.257-262
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• 2012

This study was conducted to verify the performance of the solar water circulation apparatus that was installed in a semi-closed sea area of Tongyeong to improve the water quality through removing thermocline and oxygen depleted water mass, and to prevent the occurrence of red tides caused by eutrophication. From 8 weeks of experiments, we found that the thermocline in the semi-closed sea area has been removed gradually after installation of the apparatus. The initial temperature of surface and bottom was $27.9^{\circ}C$ and $23.8^{\circ}C$, respectively and it was changed to $22.1^{\circ}C$ in both depth. In case of DO concentration, there was a big gap between surface (5.49 mg/L) and bottom (2.61 mg/L) and was an oxygen depleted water mass in the bottom area at initial. However DO concentration in bottom layer has increased gradually after operation (6.19 mg/L) and the oxygen depleted water mass has removed. Due to the effects of seasonal variation and the operation of the solar water circulation apparatus for 8 weeks, COD concentration decreased from 5.61 mg/L to 2.36 mg/L in surface area, and from 6.08 mg/L to 1.73 mg/L in bottom area. Dissolved inorganic nitrogen concentration also decreased from 0.135 mg/L to 0.050 mg/L in surface area, and from 0.076 mg/L to 0.051 mg/L in bottom area. This research was conducted from July to September, and it might be possible that the variation of water quality was affected by both seasonal variation and the operation of the water circulation apparatus. Hence a further research is required to verify the performance of the water circulation apparatus itself and to monitor dissolved inorganic nitrogen and phosphorous concentrations as well as Chl-a.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.448-454
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• 2000

This study was to examine the physicochemical characteristics of coagulation reaction between ignited oyster shell powder (IOSP) and red tide organisms (RTO), and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea,IOSP was made from oyster shell and its physicochemical characteristics were examined for particle size distribution, surface characteristic by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrotheca closterium and Skeletonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various c(Incentrations of IOSP, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number, IOSP showed positive zeta potentials of $11.1{\~}50.1\;mV\;at\;pH\;6.2{\~}12.7$, A positive zeta potential of IOSP slowly decreased with decreasing pNa 4,0 to 2,0. When pNa reached zero, the zeta potential approached zero, When a pMg value was decreased, the positive zeta potential of IOSP increased until pMg 3.0 and decreased below pMg 3.0. IOSP showed 4.8 mV of positive zeta potential while RTO showed -9.2 mV of negative zeta potential in sea water. A positive-negative EDL (electrical double-layer) interaction occurred between $Mg(OH)_2$ adsorption layer of IOSP and RTO in sea water so that EDL attractive force always worked between them. Hence, their coagulation reaction occurred at primary minimum on which an extreme attractive force acted because of charge neutralization by $Mg(OH)_2$ adsorption layer of IOSP. As a result, the coagulation reaction was rapidly processed and was irreversible according to DLVO (Deriaguin-Landau-Verwey-Overbeek) theory. Removal rates of RTO were exponentially increased with increasing both IOSP concentration and G-value. The removal rates were steeply increased until 50 mg/l of IOSP and reached $100{\%}\;at\;400\;mg/l$ of IOSP. Removal rates of RTO were $70.5,\;70.5,\;81.7,\;85.3{\%}$ for G-values of $1,\;6,\;29,\;139\;sec^(-1)$at IOSP 100 mg/l, respectively. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction.

• Journal of Life Science
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• v.22 no.11
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• pp.1493-1499
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• 2012

The level of genetic variation and relationships in three native Korean goat populations (Dangjin, Jangsu, and Tongyeong) as well as the populations of a farm were analyzed, based on 30 microsatellite markers. A total of 277 distinct alleles were observed across the four goat populations, and 102 (36.8%) of these alleles were unique to only one population. The mean observed heterozygosity and polymorphism information content were calculated as 0.461~0.651 and 0.462~0.679, respectively. In the NJ tree constructed based on Nei's $D_A$ genetic distance, the four populations represented four distinct groups. However, the genetic distances between each Korean native goat population and the farm population were two times those among the three native Korean breeds. The genetic structure within the three Korean native goat populations was also investigated. Cluster analysis, using the STRUCTURE software, suggested three clusters. The molecular information of genetic diversity and relationships in this study will be useful for the evaluation, conservation, and utilization of native Korean goat breeds as genetic resources.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.955-962
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• 1997

The food components of three kinds of edible ascidians being cultivated and caught in Tongyeong and Jisepo districts, Kyongnam of Korea were investigated. Wild Halocynthia roretzi (WM) and Pyura michaelseni (DM) were higher in contents of moisture and crude protein than cultured Halocynthia roretzi (CM). Total combined amino acid contents of CM, WM and DM muscles were 11,425.4 mg%, 11,595.4 mg% and 12,152.7 mg%, respectively, and major amino acids were Asp, Glu and Lys. The major fatty acids were 14:0, 16:0, 16:1n7, 18:1n7, 18:4n3, 20:5n3 and 22:6n3, and composition ratio of n3 polyunsaturated fatty acids of CM, WM and DM were 39.1%, 47.0% and 46.5%, respectively. In extracts components, total free amino acid contents of CM, WM and DM were 1,071.3 mg%, 1,278.7 mg% and 1,133.2 mg%, respectively, and the major amino acids were Tau, Glu, Pro, Asn, Gly, and Ala, while Arg was contained little quantities. As for nucleotides and related compounds, AMP was the principal component and IMP was detected though very small amounts in ascidian samples. Also contents of TMAO, total creatinine, betaine and peptide-N were $12.2{\sim}18.1\;mg%,\;15.5{\sim}19.6\;mg%,\;270.5{\sim}329.9\;mg%\;and\;62.0{\sim}111.0\;mg%,$ respectively. In inorganic ions of ascidian samples, the major components were $Na^+,\;K^+,\;Cl^-\;and\;PO^{3-}_4$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.8
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• pp.1265-1273
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• 2005

The purpose of this study was to prepare accelerated salt-fermented anchovy sauce using a shrimp processing byproducts (head, shell and tail) as a fermenting accelerator, and to investigate its physicochemical and enzymatic properties. Four types of sauces were prepared with 0, 10, 20, and 30$\%$ (w/w) addition of shrimp byproduct and fermented at 24$\pm$2$^{\circ}C$ for 360 days. During fermentation, all four type sauces decreased moisture content (67.5$\%$68.0$\%$ to 64.0$\∼$64.8$\%$) and pH (5.52$\∼$7.10 to 5.03$\∼$6.58), but showed increase in their crude protein (7.0$\∼$8.2 to 10.8$\%$) and volatile basic nitrogen contents (40$\∼$75 to 180$\∼$200 mg/100 g of sauce). The ratio of amino nitrogen to total nitrogen contents of control (0$\%$) and sauce with 10$\%$ shrimp byproducts (10$\%$ sauce) were maximized at 270 days, whereas 20$ \% $ and 30$\%$ added sauces were at 180 days. Endoprotease and exoprotease activities of anchovy sauces added with 20$\%$ and 30$\%$ of shrimp byproducts tend to be higher than those of control (0$\%$) and 10$\%$ addition. Proteolytic activities of sauces at pH 9 were about 2 times higher than those at pH 6. Amidolytic activities for LeuPNA decreased remarkably during fermentation, and control (0$\%$) almost lost their activity at 180 days, while additional sauces were relatively stable. These suggest that alkaline pretense of anchovy and shrimp byproducts as a endoprotease mainly contributed to the fermentation of salt-fermented sauces. The protein molecular weight distribution of sauces indicated 2 groups of peaks (peak 1,>70,000 da and peak 2, 3,000$\∼$29,000 da). As the fermentation proceeded, peak 1 tended to decrease in all of sauces, but peak 2 increased rapidly from 30 to 270 days. Optimum fermentation periods of control and 10$\%$ sauces were 270 days and those of 20$\%$ and 30$\%$ sauce were 180 days. The results suggest that shrimp byproduct can be used as accelerator of salt-fermented sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1041-1051
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• 2005

In order to assure the safety of the seaweeds, we measured the contents of the trace metals in the seaweeds harvested from Korean coastal area. We collected 620 marine algal samples from fourteen areas, and then analyzed the trace metals such as Hg, Cd, Cr, Cu, Mn, Ni, Pb and Zn. The contents of Hg, Cd, Ni and Mn were higher in the seaweeds collected from Chungnam Taean area. The contents of Cr and Cu were higher in the seaweeds collected from Yeongdeok and Tongyeong area, respectively. And Pb and Zn were highly detected from the seaweeds of Ulsan area. The mean levels of trace metals were high in the order of Zn $(48.02\pm41.20{\mu}g/g)\;>\;Mn (34.63\pm38.95{\mu}g/g)\;>\;Cu(6.29\pm6.52{\mu}g/g)\;>\;Ni(2.17\pm4.00{\mu}g/g)\; >\;Cr(1.61\pm2.35{\mu}g/g)\;>\;Pb(1.28\pm2.37{\mu}g/g)\;>\; Cd(0.67\pm0.75{\mu}g/g)\;>\;Hg(0.02\pm0.02{\mu}g/g)$. Zn was consistently most abundant metal in all samples, followed by Mn and Cu, which are very important for human health. There were higher contents of Hg and Cd in brown algae, the contents of Cr, Cu, Mn, Ni and Pb in green algae, the content of Zn in red algae among them. Additionally, significant linear correlations were observed between a total 28 different pairs of metals, of them, the correlation factor between Cr and Ni showed the highest (r=0.374, p<0.001). The trace metal contents of seaweeds varied with habitats and kinds of samples, nevertheless they showed very safe level in edible seaweeds tested. Scytosiphon lomentaria, which has been known as a little use of food, have shown a clear selectivity for Cr and Pb. Among non-edible seaweeds, Sargassum thunbergii for both Cd and Mn, Lomentaria hakodatensis for Ni and Grateloupia prolongata for Zn have shown a clear selectivity, respectively. Therefore, these seaweeds could be useful as bioindicator for each trace metal pollution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.915-923
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• 2005

We monitored paralytic shellfish poison (PSP) by HPLC method in shellfishes including a sea squirt, and its products produced in domestic and imported, total 35 species, 850 samples, collected at 9 cities such as Seoul, Busan, Daegu, Ulsan, Pohang, Masan, Tongyeong, Geoje and Sacheon, 10 times by month (2 times in April and May) from March to October, 2004. PSPs were detected in a few raw samples on March, and it showed highest toxic ratio $(72.9\%)$ on third week of April (51 samples toxic in total 70 samples) and decreased suddenly to $2.4\%$ on third week of May. After then, PSPs were detected in a few samples, sporadically, and disappeared after August. Most raw shellfishes in the market were safe from PSP, showing the toxicity below 1 MU/g (quarantine level 4.0 MU/g), except oyster collected on April at Masan (1.9 MU/g), blue mussel on April (1.8 MU/g) and purplish washington clam on May at Sacheon (2.1 MU/g). However, it was strongly suggested to survey and under control for the imported scallops and ark shells which showed highly toxic in the quarantine level on May, July, even September. PSP were not detectable in the all shellfish products collected on May, July and September, except 2 boiled and dried mussels contained trace amount (0.01 MU/g), and all those products were safe as below quarantine toxin level (4.0 MU/g).

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.4
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• pp.517-524
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• 2009

We collected 177 fishes representing 53 species of fish from the eastern (Pohang), western (Gunsan), and southern (Tongyeong) coasts of Korea, and measured their heavy metal contents. The mean recoveries of the heavy metals extracted from cod muscle (certified reference material, CRM) were $88.7{\sim}100.6%$. The mean levels of the heavy metals in the samples taken from the edible portion of each fish were high in the order of Zn ($8.981{\pm}4.835{\mu}g/g$), Cu ($0.755{\pm}0.507{\mu}g/g$), and Mn ($0.433{\pm}0.699{\mu}g/g$), which are necessary metals in the human body, and then followed by Cr ($0.206{\pm}0.181{\mu}g/g$), Ni ($0.081{\pm}0.110{\mu}g/g$), Pb ($0.038{\pm}0.046{\mu}g/g$), Cd ($0.017{\pm}0.023{\mu}g/g$). The average daily intakes of the heavy metals by the fishes were as follows: Cd (0.81 ${\mu}g$), Cr (9.98 ${\mu}g$), Cu (36.63 ${\mu}g$), Mn (21.01 ${\mu}g$), Ni (3.93 ${\mu}g$), Pb (1.84 ${\mu}g$) and Zn (435.58 ${\mu}g$). The average weekly intakes of Cd, Cu, Pb and Zn by the fishes were 1.35%, 0.12%, 0.86%, and 0.73% respectively, as compared with PTWI (Provisional Tolerable Weekly Intakes) established by FAO/WHO Expert Committee for Food Safety Evaluation.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.4
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• pp.218-234
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• 2004

Recent warm winters were evaluated for a possible shifting of the northern limit for winter barley cultivation in Korea. Therefore, safe zones for winter barley cultivation were reclassified based on the average and minimum January air temperature in recent years. The results are as follows: By analysis of mean values of January average air temperatures for 30 years (1971-2000), the northern limits for safe cultivation of hulled, naked, and malting barley were Ganghwa - Icheon - Chungju - Chunyang - Goseong, Cheonan - Geumsan - Mungyeong - Andong - Sokcho, and Gwangju - Jangheung - Sancheong - Pohang - Uljin lines, respectively. Meanwhile, based on the January average air temperature of 14 years (1987-2000) with warmer winters, the safe cultivation zone of winter barley shifted northward of the normal (1971-2000). So, the northern limits for hulled, naked, and malting barley were Pocheon - Chuncheon - Wonju - Yangpyeong - Chunyang, Ganghwa - Icheon - Chungju - Uiseong - Goseong, and Gunsan - Suncheon - Jinju - Miryang - Yeongdeok - Uljin lines, respectively. Winter barley cultivars with the strongest tolerance to low temperature can be grown up to the adjacent areas of Taebaek Mountains (that is, Inje, Hongcheon, Jecheon, and Taebaek areas). Based on January mean air temperatures of 10-year return period for 30 years (1971-2000), the northern limits for hulled and naked barley were Boryeong - Namwon - Geochang - Gumi - Goseong and Seocheon - Jeongeup - Hapcheon - Yeongdeok - Sokcho lines, respectively. It ~ppears that malting barley can be cultivated only at southern coastal areas (that is, Busan, Tongyeong, Yeosu, and Wando areas). On the other hand, based on the weather conditions of 14 years (1987-2000) with warmer winters, the northern limits for hulled, naked, and malting barley were Ganghwa - Icheon - Yeongju - Goseong, Seosan - Namwon - Mungyeong - Andong - Sokcho, and Gwangju - Jangheung - Sacheon - Ulsan - Uljin lines, respectively. The northern limit for winter barley cultivars including Olbori with the strongest tolerance to low temperature was the Ganghwa - Wonju - Chungju - Chunyang - Goseong line.

• Journal of Food Hygiene and Safety
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• v.29 no.1
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• pp.60-66
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• 2014

This test was performed to evaluate the bactericidal efficacy of a fumigation disinfectant containing 20% ortho-phenylphenol against Pseudomonas aeruginosa (P. aeruginosa) and Enterococcus hirae (E. hirae). In preliminary tests, P. aeruginosa and E. hirae working culture suspension number (N value) were $2.8{\times}10^8$ and $4.0{\times}10^8CFU/mL$, respectively. And all the colony numbers on the carriers exposed to the fumigant (n1, n2, n3) were higher than 0.5N1 (the number of bacterial test suspentions by pour plate method), 0.5N2 (the number of bacterial test suspentions by filter membrane method) and 0.5N1, respectively. In addition, the mean number of P. aeruginosa and E. hirae recovered on the control-carriers (T value) was $2.8{\times}10^8$ and $3.4{\times}10^6CFU/mL$, respectively. In the bactericidal effect of the fumigant, the reduction number of $2.8{\times}10^8$ (d value) was 6.46 and 5.19 logCFU/mL, respectively. According to the French standard for the fumigant, the d value for the effective bactericidal fumigant should be over than 5 logCFU/mL. With the results from this study, the fumigation disinfectant containing 20% ortho-phenylphenol has an effective bactericidal activity, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with the pathogenic bacteria.