• The Korean Journal of Malacology
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• v.17 no.1
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• pp.19-26
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• 2001

To study the growth of transplanted Pacific oysters, Crassostrea gigas, we sampled Korean and Japanese oysters attached in Chinhae Bay near Gaduk Island and in Seto inland sea in Japan, respectively, suspended in Pukman Bay. Water Temperature ranged from 11.2 to 27.8$^{\circ}C$ (mean 19.84 ${\pm}$ 5.47$^{\circ}C$) on the surface, and 11.1 to 23.6$^{\circ}C$ (mean 18.31 ${\pm}$ 4.18$^{\circ}C$) on the bottom. Salinity ranged from 31.45 to 34.57 (mean 33.10 ${\pm}$ 1.16) on the surface, and from 31.69 to 34.35 (mean 33.24 ${\pm}$ 1.06) on the bottom. salinity was the lowest in September and October, and the highest in December. Growth of oysters in shell height showed a significant difference after being suspended at the farm, reaching 70.3 ${\pm}$ 12.5 mm in the Korean oysters and 96.2 ${\pm}$ 14.6 mm in the Japanese oysters in December. While the Korean oysters showed relatively low growth rate and cessation of growth after sudden growth between June and July, the Japanese oysters showed continuous growth during the whole farming period, although stepwise growth was observed. It was not until September that meat weight showed a significant difference between the two. After September, there was a sudden increase in the Japanese oysters, reaching 7.5 ${\pm}$ 2.9 g in December, but growth of the Korean oysters showed slow growth rate during whole farming period, reaching 4.6 ${\pm}$ 1.9 g in December. here was an obvious decrease in the meat weight of Japanese oysters in December, which might be attributed to restriction of food. Condition factors rebounded in October in the Korean oysters and in September in the Japanese oysters, respectively, attaining 12.8 in the Korean oysters and 15.3 in the Japanese oysters at the end of investigation on December. Shell length-height regression equations were as follows: Korean oysters: S$\sub$h/=2.922S$\sub$t/,-4.8024 (r$^2$= 0.8541) Japanese oysters: S$\sub$t/=3.623S$\sub$h/,-5.1239 (r$^2$=0.7782) This showed the possibility of morphological transformation in the shell of the Korean oysters since shell height was longer than those reported by Bae et al. (1976) and Lee et al. (1992).

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.153-160
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• 2009

Pisidium (Neopisidium) coreanum is a freshwater snail and lives in spring water near mountain areas. Interestingly, this snail has been traditionally regarded as medicinal food, and thus has been used as folk remedies for healing broken bones. Recently, alpha classification on Pisidium (Neopisidium) coreanum through redescription has been conducted. However, not much attention has been made in beta classification. In this study, we performed the beta classification based on metallothionein (MT) genes found from various organisms. To this end, the complete cDNA sequences were obtained from the Expressed Sequence Tag (EST) sequencing project of Pisidium (Neopisidium) coreanum. The coding region (315 bp) encoded an amino acid sequence of 105 residues. The combined results from BLAST analyses, multiple sequence alignment and molecular phylogenetic study of Pc-MT gene indicate that Pisidium (Neopisidium) coreanum has similarity to freshwater bivalve such as Dreissena polymorpha (zebra mussel), Unio tumidus (swollen river mussel) and Crassostrea ariakensis (suminoe oyster).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.791-798
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• 1998

To develop natural flavoring substances. optimal hydrolysis conditions for two stage enzyme hydrolysates (TSEH) using low-utilized shellfishes such as purplish clam and frozen oyster stored at $-20^{\circ}C$ for 60 days. The optimal conditions for TSEH method were revealed in temperature at $50^{\circ}C$ 3 hours digestion with alcalase (Aroase AP-10, $0.3%$ w/v, pH 8.0) at the 1st stage and $45^{\circ}C$ 2 hours digestion with neutrase (Pandidase NP-2, $0.3\%$ w/v, pH 6.0) at the 2nd stage. Among water extracts, autolytic extracts and 4 kinds of enzyme hydrolysates tests, TSEH method was superior to other methods on the aspect of yields, nitrogen contents, taste such as umami and control of off-flayer formation, and transparency of extracts. From the results of chemical experiments and sensory evaluation, we may conclude that TSEH from low-utilized marine products is more flavorable compared the conventional enzyme hydrolysates, it could be commercialized as the seasoning substances.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.43-57
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• 1977

In order to establish methods of potato processing for mixed cooking with rice as main diet, treatment for polyphenol oxidase inactivation in potato tissues, and safety in regard to sanitation were studied. The results were summarized as follows: 1. Cut potato granule which were blanched in boiling water are practical and best in color within $3{\sim}6\;minutes$ dipping. 2. Dipping treatment of potato granules in a saline solution is not pratical because of the resulting color and saline taste. 3. Dipping treatment of potato granules in a boiling saline solution is not practical because of residual salt. 4. Dipping treatment of potato granules in low concentration of hydrochloric acid solution is not effective in color changes but dipping treatment from 0.1N concentration for 4-10 minutes to 0.5N concentration for $1{\sim}10minutes$ shows good effects. 5. Dipping treatment in boiling hydrochloric acid solution of 0.04-0.068N concentration for 3-5 minutes dipping is practical for its resulting color. 6. Dipping treatments in 0.05% of $K_2S_20_5$ solution for $50{\sim}60\;minutes$ and in 0.06% for $40{\sim}60\;minutes$ and 0.065% for $10{\sim}60\;minutes$ shows a small palatability in color but its boiled potato granules shows good color 7. Treatments for any time in $0.01{\sim}0.03%$ of boiling $K_2K_20_5$ solution after predipping in its cold solution for longer time than 30minutes show effective in the color and palatability of the potato granules and their cooked ones. 8. From the view of food sanitation, dipping treatment of the potato granules in the solution of $K_2S_20_5$ is safe because of the few residual amount of $SO_2$. 9. All the methods of treatment that potato granules are dipped for any time at 0.01% of $K_2S_20_5$ solution are safe from the view of fond sanitation. At 0.03% of $K_2S_20_5$ solution, nothing but the methods of treatment that they are dipped within 30 minutes and boiled within 4 minutes are safe.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.80-98
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• 2002

Taxus cuspidata Sieb selected cultivation as drug, food and decorative plant in Kyong-gi province in Korea. As a manufacturing method, there were extracted from 250g of dried-leaf and 300g of dried-stem with each 200g of BG, PG and water (to 100) mixing for 72 hour at 50$\pm$5$\^{C}$ and then they were filtered by 400-mesh filter. Appearance of extract of leaves was slight brown, pH=5.3$\pm$0.5, gravity was 1.012$\pm$0.05, and a reflective index was 1.375$\pm$0.05. And appearance of extract of stems was slightly dark brown, pH=5.4$\pm$0.5, gravity was 1.016$\pm$0.05, and a reflective index was 1.358$\pm$0.05. It was extracted oil from Taxus seed. Gravity was 0.922$\pm$0.05 and it should be obtained the 27.0$\pm$0.5% of yield. The molecular weight of polysaccharide was about 50,000 to 300,000 dalton and contained 5.0$\pm$1.2% of yield from Taxus fruit. The determinations of total polyphenols in measuring spectropotometer got 0.563% in leaves, and 0.325% in stems, whereas the quantitives of total tannins got 0.054% and 0.037%, respectively. As the effects in Cosmetics by DPPH-method, the antioxidative activities were very strong that the inhibitory ratio showed 75% in leaves and 64% in stems compared with 52% in greentea extract. These are more effective than other plant extracts. The increasing ratio of collagen synthesis rate on the activating fibroblast for extracts of Taxus cuspidata Sieb showed 54.16% (stems) and 33.18% (leaves), To improve the skin elasticity, PPE(porcine pancreatic elastase)-inhibitory activities were strongly effective as 13,7% (stems), 23.5% (leaves) and 66%(seed). Anti-inflammatory acitvity of seed oil was very the above 41% stronger than SG was 24% of anti-Inflammatory as a control sample.

• Korean Journal of Poultry Science
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• v.45 no.4
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• pp.261-272
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• 2018

This study was conducted to evaluate the difference in the quality of chicken thigh meat from conventional and animal welfare farms during refrigeration storage over 9 days. Chicken thigh meat from conventional (CTC, n = 30) and animal welfare farms (CTW, n = 30) was tested. The pH value was significantly lower in CTW (6.28) than in CTC (6.37) on day 1; however, no significant differences were found on subsequent days. The yellowness of CTW was higher than that of CTC on day 1, but CTW showed lower yellowness than did CTC on day 7 and 9. The cooking loss, water holding capacity, lightness, redness, and coliform levels of CTC did not show any significant difference when compared with CTW during storage. The shear force of CTW was significantly higher than that of CTC on day 1, 3, 7, and 9. Total microorganism and coliform in CTC and CTW increased with increasing storage days. On day 7 and 9, the total microorganism level of CTW was lower than that of CTC. The thiobarbituric acid value of CTW was lower than that of CTC on day 9. The volatile basic nitrogen (VBN) of CTW was lower than that of CTC during storage. Anserine content and 1,1-diphenyl-2-picryl-hydrazyl(DPPH) scavenging activity of CTW was significantly higher than CTC on day 1. These results suggest that CTW stayed fresher for longer than did CTC because of low total microorganism level on day 7 and 9, and VBN during refrigerated storage.

• Journal of Life Science
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• v.19 no.5
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• pp.633-638
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• 2009

We investigated the inhibitory effects of solvent extracts from dried tuna on the growth of cancer cell lines (HT1080 human fibrosarcoma and HT-29 human colon cancer cells) and $H_2O_2$-induced oxidative stress. Inhibitory effects of acetone with methylene chloride (A+M) and methanol (MeOH) extracts on the growth of HT1080 and HT-29 cancer cells increased in a dose dependent manner (p<0.05). The inhibitory effect was more significant on the growth of HT1080 cells, and A+M extracts had a higher inhibitory effect compared to MeOH extracts. The treatments of hexane, 85% aq. methanol, butanol and water fractions significantly inhibited the growth of both cancer cells (p<0.05). Among the fractions, hexane and 85% aq. methanol fractions showed higher inhibitory effects. In order to determine the protective effect on $H_2O_2$-induced oxidative stress, a DCHF-DA (dichlorodihydrofluorescin diacetate) assay was conducted. All fractions, including crude extracts of dried tuna, appeared to significantly reduce the levels of intracellular reactive oxygen species (ROS) with dose responses (p<0.05). Among the fractions, BuOH and 85% methanol fractions showed a higher protective effect on the production of lipid peroxides. These results indicate that the consumption of tuna may be recommended as a potent functional food for preventing cellular oxidation and cancer.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.1
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• pp.158-167
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• 2006

The object of this study is to detect of land-cover change in western DMZ and vicinity. This was performed as a basic study to construct a decision support system for the conservation or a sustainable development of the DMZ and Vicinity near future. DMZ is an is 4km wide and 250km long and it's one of the most highly fortified boundaries in the world and also a unique thin green line. Environmentalists want to declare the DMZ as a natural reserve and a biodiversity zone, but nowadays through the strengthening of the inter-Korean economic cooperation, some developers are trying to construct a new-town or an industrial complex inside of the DMZ. This study investigates the current environmental conditions, especially deforestation of the western DMZ adopting remote sensing and GIS techniques. The Land-covers were identified through the linear spectvral mixture analysis(LSMA) which was used to handle the spectral mixture problem of low spatial resolution imagery of Landsat TM and ETM+ imagery. To analyze quantitative and spatial change of vegetation-cover in western DMZ, GIS overlay method was used. In LSMA, to develop high-quality fraction images, three endmembers of green vegetation(GV), soil, water were driven from pure features in the imagery. Through 15 years, from 1987 to 2002, forest of western DMZ and vicinity was devastated and changed to urban, farmland or barren land. Northern part of western DMZ and vicinity was more deforested than that of southern part. ($52.37km^2$ of North Korean forest and $39.04km^2$ of South Korean were change to other land-covers.) In case of North Korean part, forest changed to barren land and farmland and in South Korean part, forest changed to farmland and urban area. Especially, In North Korean part of DMZ and vicinity, $56.15km^2$ of farmland changed to barren land through 15 years, which showed the failure of the 'Darakbat' (terrace filed) project which is one of food increase projects in North Korea.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.230-240
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• 2015

An IOM sampler equipped with glass fiber filter has been recently utilized instead of solid adsorbent, which was used to measure the inhalation exposure of agricultural operator to pesticides. The aim of this study is to validate the efficacy of an IOM sampler by measuring the trapping efficiency and breakthrough using kresoxim-methyl water-dispersible granule and fenthion emulsifiable concentrate. On LC-MS/ MS, minimum detection level was 12.5 pg and method limit of detection was 5.0 ng/mL. Good linearity ($R^2$ > 0.999) for matrix matched standards was obtained. Recoveries of pesticides from glass fiber filter were 102-109% (kresoxim-methyl) and 97-104% (fenthion) while those from XAD-2 resin were 94-98% (kresoxim methyl) and 93-100% (fenthion). Trapping efficiency test was performed with personal air pumps and IOM sampler (glass fiber filter) connected with solid adsorbent (XAD-2 resin) with two types of formulation (solid and liquid) which were diluted by standard rate and sprayed to IOM sampler. Those pesticides were trapped only in glass fiber filter without any breakthrough to solid adsorbent. After spiking of pesticides to glass fiber filter, breakthrough test was carried out with IOM sampler (glass fiber filter) which was connected with solid adsorbent. As a results, 87-101% of kresoxim-methyl and 96-105% of fenthion remained in spiked glass fiber filter, however, no pesticides were detected in second glass fiber filter and solid adsorbent. In conclusion, IOM sampler which equipped with glass fiber filter can be applied widely for pesticide inhalation exposure study since it has good trapping efficiency and adsorption capacity, regardless of the solid or liquid formulation.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.201-210
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• 2017

BACKGROUND: The current study was to monitor of 9 veterinary antibiotics (ceftiofur, clopidol, florfenicol, sulfamethazine, sulfamethoxazole, sulfathiazole, tetracycline, tiamulin, and tylosin) in manure using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in positive and negative electrospray ionization mode. METHODS AND RESULTS: Sample preparation was carried out using Mcllvaine buffer and citrate salts to adjust the pH of the sample followed by purification with dispersive solid phase extraction (d-SPE). Separation of analytes during LC-MS/MS analysis was conducted using an Eclipse Plus $C_{18}$ column and the mobile phase was in gradient mode with, 0.1% formic acid and 5 mM ammonium formate in methanol (A) and 0.1% formic acid and 5 mM ammonium formate in distilled water (B). The linearity of the matrix-matched calibrations of all tested antibiotics was good, with $R^2$ determination coefficients ${\geq}0.9920$. The limit of detection (LOD) and quantifications (LOQ) were $0.1-67.0{\mu}g/kg$ and $0.4-200.0{\mu}g/kg$, respectively. Analysis of 13 solid and liquid manure samples taken from the Republic of Korea revealed concentrations less than $0.7{\mu}g/kg$ for tiamulin, $1497.6{\mu}g/kg$ for sulfamethazine. CONCLUSION: To monitor 9 veterinary antibiotics from manure samples in 13 provincial areas throughout the Republic of Korea, an analytical method was developed. The developed method was fully validated and successfully applied for monitoring various veterinary antibiotics in manure samples.