• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.363-367
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• 1983

Low salt fermented products of anchovy, Engraulis japonica, caught in the coasts of East Sea of Korea, were prepared tentatively and also discussed the retarding effect of rancidity of the product by the addition of BHA or red pepper. Fresh anchovies were purchased from Kichang fish market. The raw samples were mixed with $8\%$ table salt, $0.5\%$ lactic acid, $6\%$ sorbitol, $4\%$ ethyl alcohol and $0.02\%$ BHA or $0.5\%$ red pepper and filled in the glass bottles and sealed with the cap. Conventional fermented product of anchovy as a control was prepared from fresh anchovy and $20\%$ salt only. After preparation, the products were fermented for 90 days at room temperature. Amino-nitrogen, TBA value, peroxide value and viable counts of bacteria of these products were determined and also evaluation of their qualify was compared with control product by sensory evaluation during fermentation. Amino-nitrogen contents of the low salt products reached a peak in 55 days of fermentation, and the volatile basic nitrogen contents ranged $100\;mg\%$ even after 90 days of fermentation. Thiobarbituric acid value of the product with $0.02\%$ BHA showed a little increase up to 65 days of fermentation regardless of salt contents, while that of the control product increased sharply up to 65 days and then decreased gradually. BHA was effective on retarding rancidity of fermented products of anchovy and red pepper was also slightly effective. All the products showed the highest cell population in about 55 days of fermentation. Judging from the results of analysis and sensory evaluation, the low salt fermented product of anchovy could be prepared with $8\%$ salt, $0.5\%$ lactic acid, $6\%$ sorbitol, $4\%$ ethyl alcohol and $0.02\%$ BHA or $0.5\%$ red pepper to the fresh round anchovy.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.947-956
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• 2009

Residual petroleum hydrocarbons after an oil spill may accumulate in the marine benthic ecosystem due to their high hydrophobicity. A lot of monitoring data are required for the estimation of ecosystem exposure to residual petrochemicals in an ecological risk assessment in the affected region. To save time and cost, the environmental exposure to them in the affected ecosystem can also be assessed using a simple food-web bioaccumulation model. In this study, we evaluated residual concentrations of four selected polycyclic aromatic hydrocarbons (phenanthrene, anthracene, pyrene, and benzo[a]pyrene) in a hypothetic benthic ecosystem composed of six species under two exposure scenarios. Body-residue concentration ranged 5~250 mg/kg body depending on trophic positions in an extreme scenario in which the aqueous concentrations of PAHs were assumed to be one-tenth of their aqueous solubility. In addition, bioconcentration factors (BCFs) and bioaccumulation factors (BAFs) were evaluated for model species. The logarithm of bioconcentration factor (log BCF) linearly increased with increasing the logarithm of 1-octanol-water partition coefficient (log $K_{OW}$) until log $K_{OW}$ of 7.0, followed by a gradual decrease with further increase in log $K_{OW}$ without metabolic degradation. Biomagnification became significant when log $K_{OW}$ of a pollutant exceeded 5.0 in the model ecosystem, indicating that investigation of food-web structure should be critical to predict biomagnifications in the affected ecosystem because log $K_{OW}$ values of many petrochemicals are higher than 5.0. Although further research is required for better site-specific evaluation of exposure, the model simulation can be used to estimate the level of the ecosystem exposure to residual oil contaminants at the screening level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.423-428
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• 1998

The effective extraction methods and chemical components of crude polysaccharides of ascidian tunics were investigated. Tow extraction conditions, autoclaving or enzyme treatment, were applied. The proximate composition of ascidian tunics was not much different between those dried in raw (containing pigments) and those acetone treated and dried (decolorized), showing $50\%$ of carbohydrate and $40\%$ of protein. It was possible to extract up to $10\%$ of crude polysaccharides from ascidian tunics regardless of the extraction methods, autoclaving or enzyme treatment. In case of the latter the extraction yield by neutrase was higher than that with alkalase (Novo co.) or mixture 2000 (Pacific chemical co.). The most effective enzyme concentration and extraction time appeared to be 24 hrs of extraction with $3\%$ neutrase. On the other hand, in autoclave treatment, 6 hrs extraction showed most desirable extraction yield, about $9.7\%$. The compositions of amino acid of decolorized ascidian tunic (acetone treated group) and the crude polysaccharide from the autoclaving (water solubles) or neutrase treatment (enzyme digestibles) were similar to each other. Histidine was the highest both in the neutrase and autoclave treatment group and the yield were $29.2\%,\;20.4\%$, respectively, followed by aspartic acid and glutamic acid. Among the minerals, the content of Ca was significantly high, followed by Mg and Na.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.2
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• pp.259-266
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• 1998

A study on the biological and chemical characteristics in the middle last Sea of Korea was carried out at 31 stations in October $11\~18$, 1995 on board the R/V Tam-Yang. The chlorophyll a concentration, new and regenerated production, and the vertical diffusion of nitrate from the thermocline structure were investigated. From the vertical distribution of chlorophyll a, subsurface maxima were observed near the thermorline at most stations including the frontal zone, except at the southern stations where the maximum chloropyll a concentration occurred at the surface, The nanophytoplankton was the most dominant fraction comprising $83.5\%$ of total phytoplankton cell numbers, but netphytoplankton were common at the southern stations where the dominant species were Rhizosolenia sp. Nitrogenous new production and regenerated productions were measured using the stable isotope $^{15}N$ nitrate and ammonia uptake method. The vertically integrated nitrogen production varied between 8.470 and $72.945\;mg\;N\;m^{-2}\;d^{-1}$. The f-ratio, which is the traction of new production from primary production, waried between 0.03 and 0.72, indicating that $3\%$ to $72\%$ of primary production was supported by the input of nutrients from below the euphotic zone and the rest are supported by ammonia recycled within the euphotic layer. This range of f-ratio encompasses from extremely oligotrophic to eutrophic area characteristics. The differences in productivity and f-ratio among stations were related to frontal structure and the bottom topography. The values were high near the frontal zone and low outside of it, and the station near Ulleng Island showed the highest f-ratio. Vertical diffusion coefficients were calculated from both the water column stability (Kz-1) of King and Devol's equation (1979) and new nitrogen requirement (Kz-2). The values of Kz-2 ($0.11\~0.55\;cm^2/s$) were relatively low compared to the values reported previously.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.107-113
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• 1994

Among the currently recognized pathogenic vibrios, V. vulnificus and V. cholerae non O1 are the most serious bacteria from the point of view of sea food hygiene in Korea. In this paper, the authors compared the hemolytic activities of the crude hemolysin produced by V. vulnificus and V. cholerae non O1 isolated from shellfish collected in Chungmoo, Korea. The authors also attempted to improve the purification method of V. vulnificus hemolysin(VVH) and tried to make antiserum with the purified hemolysin. VVH was produced in abundance in heart infusion broth containing $2\%$ NaCl in a shaking cultivation process(140rpm) at $37^{\circ}C$ for 15 hours. While hemolysin production patterns of V. cholerae non O1 were quite different by the strain during the culture times compared with the V. vulnificus. Hemolytic activity of the VVH on sheep erythrocytes was stronger than those of rabbit, but hemolytic activities of the hemolysin produced by V. cholerae non O1 on rabbit erythrocytes were as much as twice as strong as on those of sheep and horse. VVH was purified by two steps of hydrophobic column chromatography on Phenyl-Sepharose HP with Fast Protein Liquid Chromatography(FPLC). Purification fold and yield of VVH was much improved by changing the elution buffer's pH from 6.0 to 9.8 and adding $1\%$ CHAPS(a zwitter ionic detergent) and $50\%$ ethylene glycol to the 10mM glycine buffer during the repeated hydrophobic column chromatography. Homogeneity of the purified hemolysin was shown by polyacrylamide gel electrophoresis. According to the five times repeated purification results, the specific activity was increased 27500 times and the yield was improved by $23.4\%$ on average. About $250{\mu}g$ of purified hemolysin was harvested from the 2400ml of culture supernatant of V. vulnificus. Molecular weight of VVH was estimated to be 50KDa by the SDS-PAGE and the neutralization scores of the obtained antiserum acting against VVH were $2000{\sim}8500$.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.71-82
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• 2016

Through literature review and on-site survey of Gimcheon Bangcho pavilion(芳草亭), the features of garden design(庭園意匠) including geographic conditions, landscape modeling of Nujeong(樓亭) and Jidang(池塘, Pond), and scenic interpretations in Nujeong Jeiyoung poetry(樓亭題詠詩) have been carefully researched and the findings are presented below. Bangcho pavilion is located in a village called Wonteomaeul, which belongs to the feng shui state of golden hairpin and floating lotus. It has long been the cultural hub of communication and social interactions among the villagers. The Head House of Jeongyanggong(靖襄公宗宅), the main house(本第) of the Yeonan Yi Clan(延安李氏), is about 150m away from Bangcho pavilion, an artistic space whose landscape modeling is of the form called Nujeong. The name 'Bangcho' reflects the noble man(君子)'s determination: "I yearn for the place where honey parrots fly and the fragrant grass grow." From the two story structure of the pavilion where there is an additional floor installed to the central ondol room by a four-sided subdivision door, one can detect the aspiration of the men for pursuing an open view. One can also observe the efforts in designing the room to be used for multiple purposes from a private place to an office for periodic publication of a family lineage document called "Garyejunghae(家禮增解)". Bangcho pavilion's main sight of interest is Mrs Choi's Pond(崔氏潭), the one and only garden structure that comprises the twin round island of square pond(方池雙圓島) among the existing Jidangs in Korea. In this special Jidang, there are two coexisting islands that represent a well thought out garden facility for symbolizing conjugal affection and unyielding fidelity between master and servent(主從). In addition, the three inflows and one outflow facing the Ramcheon valley is regarded as an ideal garden design optimized for performing the function of a village bangjuk which is the site for undercurrent creation and ecological reprocessing. At present, Giant pussy willow is the only circular vegetation identified in the area of Bangcho pavilion, although this plant species is about to wither away judging from the signs of decrepitude that seems to persist for two out of three weeks. The old pine tree that appears in the 1872 Jeiyoung poetry of Byeongseon Song(宋秉璿) no longer exists. Anjae(安齋) Jang Yoo(張瑠)'s "Eight Scenary on Bangcho pavilion(芳草亭八詠)" and its expansive reproduction "Ten Scenary on Bangcho pavilion(芳草亭十景)" from Gwagang(守岡) Lee Manyoung(李晩永) depict vividly the pastoric scenery of an idyll(田園景) that stretches throughout the natural and cultural landscape of the province of Gimcheon and Guseong surrounding the Bangcho pavilion. The Bangcho pavilion sutra aims to establish Bangcho pavilion and the village of Wonteomaeul as the centre of microcosmos by dividing and allocating its scenic features according to the four seasons and times(四季四時), the eight courses(八方) and the meteorological phenomena, and it is the incarnation(顯現) of landscape perception upon the Byeol-seo Scenic site of Bangcho pavilion, the cultural hub of the region.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.519-528
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• 1993

The biodegradation experiment, the TOD analysis and the element analysis for dispersant, Bunker-C and dispersant/Bunker-C oil mixtures were conducted for the purposes of evaluating the biodegradability of dispersnat/Bunker-C oil mixtures and studying the consumption of dissolved oxygen with relation to biodegradation in the seawater. The results of biodegradation experiment showed the mixtures with $1:10{\sim}5:10$ mix ratios of dispersant to 4mg/l of Bunker-C oil to be $0.34{\sim}2.06mg/l$ of $BOD_5$ and to be $1.05{\sim}5.47mg/l$ of $BOD_{20}$ in natural seawater. The results of TOD analysis showed 1mg of Bunker-C oil to be 3.16mg of TOD. The results of element analysis showed the contents of carbon and hydrogen to be $87.3\%\;and\;11.5\%$ for Bunker-C oil, respectively, but nitrogen element was not detected in Bunker-C oil. The biodegradability of dispersant/Bunker-C oil mixture shown as the ratio of $BOD_5$/TOD was increased from $3\%\;to\;11\%$ as a mix ratio of dispersant to 4mg/l of Bunker-C oil changed from 1:10 to 5:10, and the mixtures were found to belong in the organic matter group of low-biodegradability. The deoxygenation rates($K_1$) and ultimate oxygen demands($L_o$) obtained through the biodegration experiment and Thomas slope method were found to be $0.072{\sim}0.097/day$ and $1.113{\sim}6.746mg/l$ for the mixtures with $1:10{\sim}5:10$ mix ratios of dispersant to 4mg/l of Bunker-C oil, respectively. The ultimate oxygen demand of mixture was increased as a mix ratio of dispersant to Bunker-C oil changed from 1:10 to 10:5. This means that the more dispersants are applied to the sea for Bunker-C oil cleanup, the more decreases the dissolved oxygen level in the seawater.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.241-250
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• 1992

This study was covered the amount of food consumed per day as well as methods estimating the daily food consumption per fish of Agrammus agrammus in natural population to understand flow of food organisms among trophic levels in bio-community of the coastal waters, Shinsudo, Samchonpo. The estimating formulas were induced from the mathematical models that representing the diurnal fluctuation of the stomach fullness of the fish. The daily food consumption could be estimated by both feeding rates and gastric evacuation rates, but it was more reasonable method that based on gastric evacuation rates than feeding rates. The daily food consumption in wet weight per fish by gastric evacuation rates were 1.9856g/day, 3.4725g/day, 4.4418g/day, 5.8168g/day, and 7.2113g/day in the order of age groups from 0 to 4. The daily rations as percentage of body weight were $9.35\%,\;6.65\%,\;5.76\%,\;4.72\%\;and\;5.31\%$ in the order of ages. The daily food consumption was proportional to the body weight of fish, but the daily food consumption per specific body weight was reciprocal to the body weight. Annual food consumption in wet weight. per fish by gastric evacuation rates were 529.98g from the age of 0.25 to 1.0, 1,269.28g from the age of 1.0 to 2.0, 1,622.76g from the age of 2.0 to 3.0, 2,125.57g from the age of 3.0 to 4.0, 1,316.09g from the age of 4.0 to 4.5 The amount of food consumed per fish during 4.25 years, from the age of 0.25 to 4.5, was 6,863.68g in wet weight. the relationships between the daily food consumption(Dr) by gastric evacuation rates and the total length(L, cm) or the body weight(W, g) were as follows: $$Dr=0.036L^{1.702}$$ $$Dr=0.254W^{0.664}$$

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.457-468
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• 1995

In order to develop a more practical culture system from the present running seawater tank system, two experiments of environmental factors, growth, survival rate and rearing density of olive flounder (Paralichthys olivaceus) were carried out for two consecutive years. Two groups of fish in initially averaging 7.5cm of total length, and 3.4g of body weight (EXP. I) and 5.0cm and 1.8g (EXP. II) were reared in the semi-closed recirculating seawater system equipped with the rotating biological contactors with the commercial culture scale. The dissolved inorganic nitrogen concentrations is EXP. I ranged 0,247-0.512 ppm of $NH_4-N$ (0.010-0.043 ppm of$NO_2-N$, and 0.108-0.342 ppm of $NO_3-N$, and those in EXP. II were 0.091-0.715 ppm, 0.002-0.045 ppm, and 0.007-0.277 ppm, respectively. Daily feeding rates of the fish were $0.67-2.41\%$ in EXP. I and $0.69-2.22\%$ in EXP_ II, and teed efficiency were $34.8-59.8\%\;and\;40.5-88.4\%$ in EXP. I and II, respectively. The average total ten說h and body weight were 40.0-42.8cm and 695.0-852.69g after 340 days culture in EXP. I, and 36.7-39.7cm and 552.4-706.4 g after 365 days culture in EXP. II, respectively. Survival rates of the fish at the end of EXP. I and II were $92.0\%\;and\;96.0\%,$ respectively. The ratio to body surface area of non-ocular side in all fish to bottom area of rearing tank, so-called covering rate, was used as an indicator of rearing density. The highest cowering rate and weight density of fish per $m^2$ of rearing tank at the end of experimental period were 2.2 and 34.1kg in EXP. I, and 2.6 and 36.3kg in EXP. II, respectively. For the commercial culture of olive flounder, the semi-closed recirculating seawater system was found to be more effective than the running seawater tank system in aspect to the fish productivity and protection of marine environment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.4
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• pp.475-488
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• 1995

In order to see the seasonal variation of nutrients and the limiting factors to the primary production in Deukryang Bay, both dissolved inorganic nutrients and salinity were measured in the surface waters during the periods from July 1992 to March 1993. The mean value of salinity was the lowest in ?all and the highest in early spring. Dissolved inorganic nitrogen (DIN) was the highest in winter and the lowest in summer. However, both phosphate and silicate were the highest in summer and the lowest in fall. Salinity was generally higher in the outer region than in the inner region of the bay.DIN content was nearly depleted (less than $2{\mu}M$) in summer. From fall to spring, DIN content was nearly depleted in the inner region and relatively high in the outer region of the Day. Phosphate was the highest in summer showing an opposite distribution pattern to salinity, and it was nearly depleted (less than $0.1{\mu}M$) in fall and winter. In spring, however, phosphate content was slightly high in the outer region. Silicate content showed an opposite distribution pattern to salinity in summer. in other seasons, However, the distribution pattern of silicate was similar to the salinity. DIN seemed to be a limiting factor for the primary production at all area of the bay in summer and at the inner region in other season. However, phosphate seemed to be a limiting factor at all area of the bay in fall and winter and at the inner region in spring. Silicate may limit the production of diatoms at the inner region of the bay in winter and spying. Both phosphate and silicate showed a good inverse relationship with salinity in summer, which indicates inputs of these nutrients from the freshwater runoff. In the other seasons, both nitrate and silicate showed a positive linear relationship with salinity in the outer region of the bay, suggesting that these two nutrients were mainly supplied by the inflow of the offshore costal water which had high nitrate content associated with vertical mixing.