• Journal of Food Hygiene and Safety
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• v.35 no.6
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• pp.567-573
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• 2020

The persimmon is commonly cultivated in temperate regions of the world, including China, Korea, Japan, Brazil, Turkey, and Italy. In some Asian cultures, consumers are aware of the health claims related to the persimmon and its functional ingredients. The rich phytochemistry of the persimmon has opened new avenues of research on diet-based regimens designed to cure various ailments. This study was conducted to identify the genotoxicity of immature green persimmon (Diospyros kaki THUNB.) extract (DKA). The bacterial reverse mutation assay, the chromosomal aberration assay, and the mammalian micronucleus test were performed to determine the DKA genotoxicity. The result of the bacterial reverse mutation assay revealed that the DKA did not induce mutagenicity in Salmonella typhimurium TA98, TA100, TA1535, TA1537 and Escherichia coli WP2uvrA with or without metabolic activation of S9 mixture. The oral administration of DKA also caused no significant increase in the number of micronucleated polychromatic erythrocytes or in the mean ratio of polychromatic to total erythrocytes. In addition, DKA did not cause a significant chromosome aberration on CHL cells in the presence or absence of S9 activation. In conclusion, DKA could be considered as a reliable and safe functional food since no toxicity was found under the condition of this study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.477-493
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• 2020

This study conducted a seasonal survey to analyze the spatio-temporal variations of marine environments and phytoplankton community in Gochang Coastal Waters (GCW) from August 2016 to April 2017. In the results, the water temperature ranged from 2.1℃ to 34.5℃, showing a large seasonal variation, but the salinity changed from 31.14 psu to 32.64 psu. Therefore, the seasonal variations of water types in GCW were mainly determined by water temperature. The phytoplankton community consisted of 53 genera and 86 species, showing a relatively simple distribution. The phytoplankton cell density ranged from 2.2 to 689.2 cells mL^-1, with an average of 577.2 cells mL^-1, which was low in autumn and high in winter. The seasonal succession of phytoplankton dominant species was mainly diatoms during the whole year, Leptocylindrus danicus, Chaetoceros curvisetus, Skeletonema costatum-ls in summer, Paralia sulcata, Eucampia zodiacus in autumn, S. costatum-ls, Thalassiosira nordenskioeldii in winter, and S. costatum-ls, Asterionella glacialis in spring. In other words, the phytoplankton community showed high diversity in GCW throughout the year. According to the PCA, GCW were easily heated and cooled by radiant energy at lower depth, and the seasonal distributions of phytoplankton were determined by the supply of nutrients by re-fuelling of surface sediments due to the seawater mixing such as tidal mixing.

• Korean Journal of Ecology and Environment
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• v.39 no.3 s.117
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• pp.340-351
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• 2006

To reveal physicochemical factors contributing to variation of phytoplankton communities, the study was carried out biweekly at 6 stations from Feb. 2004 to Feb. 2005 in the lower part of the Han River, Korea. As results, water temperature was changed from $0.3^{\circ}C$ to $26.6^{\circ}C$, pH: 6.6${\sim}$9.1, DO: 1.89${\sim}$22.23 mg $L^{-1}$, BOD: 0.38${\sim}$9.20 mg $L^{-1}$, COD: 1.4${\sim}$15.2 mg $L^{-1}$, Conductivity: $62.5{\sim}500.0\;{\mu}s\;cm^{-1}$, SS: 3.00${\sim}$159.3 mg $L^{-1}$, and Chl a $1.7{\sim}71.3\;{\mu}g\;L^{-1}$. Phytoplankton standing crops ranged from min. $3.6{\times}10^2\;cells\;mL^{-1}$ (July 2004, St. 3) to max. $2.3{\times}10^4\;cells\;mL^{-1}$ (Feb. 2005, St. 6), and mean of those varied from $5.9{\times}10^3\;cells\;mL^{-1}$in spring, $2.1{\times}10^3\;cells\;mL^{-1}$ in summer, $4.1{\times}10^3\;cells\;mL^{-1}$ in autumn and $8.5{\times}10^3\;cells\;mL^{-1}$ in winter, respectively. In order to investigate factors influencing the total phytoplankton standing crops a multiple regression analysis was adopted for the correlation between standing crops and environmental factors. The coefficient of determination ($R^2$) value of the regression was 0.465, it showed that environmental factors which predominantly influenced phytoplankton standing crops were water temperature, COD, $NO_2-N$, $PO_4-N$, Discharge and pH. six stations could be divided into 3 groups based on similarity index in terms of environmental factors. In ANOVA analysis for physicochemical and biological factors, water temperature, chlorophyll a, silicate, phytoplankton standing crops were the same group differed little from stations. However, Station 1and 2 were grouped followed in dissolved oxygen, conductivity, COD, nitrite, nitrate, ammonia and phosphate, and Station 3, 4 and 5 were followed in dissolved oxygen, conductivity, pH and phosphate.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.37-44
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• 2013

This study was to investigate water quality and biotic community characteristics in Juam Lake. In water quality, water temperatures was $3.8{\sim}21.2^{\circ}C$, 6.7~8.6 in pH, $64{\sim}76{\mu}s\;cm^{-1}$ in Conductivity, $5.3{\sim}13.2mg\;L^{-1}$ in DO, $2.5{\sim}3.3mg\;L^{-1}$ in COD, $1.0{\sim}5.1mg\;L^{-1}$ in SS, $0.622{\sim}0.841mg\;L^{-1}$ in T-N, $0.007{\sim}0.019mg\;L^{-1}$ in T-P and $2.8{\sim}8.8mg\;m^{-3}$ in Chl-a. Revised Carlson's Index (TSIm) assessment using total phosphorus (TP) and chlorophyll-a domonstrated that the trophic states of Juam Lake were rated as mesotrophic. A total of 53 species of phytoplankton were identified. They were 28 Bacillariophyceae, 13 Chlorophyceae, 3 Cyanophyceae, and 9 Other algal taxa. The standing crops of phytoplankton was ranged from $113cells\;mL^{-1}$ to $2,909cells\;mL^{-1}$. A total of 16 species of zooplankton were identified (10 rotifers, 4 cladocerans and 2 copepods). Total zooplankton abundance was $309ind.\;L^{-1}$ to $435ind.\;L^{-1}$. The collected benthic macroinvertebrates from the surveyed sites in Juam Lake were 1,038 individuals, 33 species, 21 families and 12 orders. A dominant species was Uracanthella rufa and a subdominant species was Ecdyonurus kibunensis. Hydrophytes recorded from Juam Lake were identified 9 taxa. Emerged plants, floating plants among the hydrophytes was classified 8, 1 taxa, respectively. Ecosystem disturbance wildplant by Environment Ministry found were Paspalum distichum var. distichum and Ambrosia artemisiaefolia. A total of 30 species (6 families) were collected fishs from Juam Lake. There were 10 Korean endemic species (33.3% of collected species number) and 3 exotic species (10.0%).

• Korean Journal of Environmental Biology
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• v.17 no.4
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• pp.529-541
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• 1999

In order to elucidate characteristics of water quality, investigation of monthly dynamics of environmental factors and algal populations at major four stations of the mid and lower part in Taechong Reservoir was performed from June 1998 to June 1999. Water temperature, DO and pH were ranged 5.3~27.7$^{\circ}C$, 6.2~13.8 mgO$_2$/1 and 6.4~9.5, respectively. Those were varying as the season changes. Among inorganic nitrogen nutrients, NH$_4$was ranged from 5.5% to 7.2% of NO$_3$and NO$_3$was almost same through the seasons except summer in which it was low. SRP and SRSi were increased in summer when the blue-green algae became dominant. Those were decreased as the cell density of diatom increased when the water temperature dropped. Therefore SRSi was considered to be another important nutrient factor contributing to the increment of biomass of freshwater algae as well as SRP. Average chi-$\alpha$ concentration ranged from s to 12 $\mu$g/1 and in the lower part or the reservoir, the lowest was found. Moreover, there were remarkable increment in summer when TN/TP ratio were decreasing from relationships between TN/TP ratio and chi-$\alpha$ concentration. Annual mean ratio of TN/TP ratio was relatively high as the value was 110, which was relatively high, and it showed that P is the dominant factor in the algal growth. The dynamics of phytoplankton were simply dominated by a few species seasonally. In summer, blue -green algae such as Anabaena, Microcystis and Oscillatoria were dominant and algal bloom of blue -green began from early summer, sustained to late autumn. The average standing crops of A. spiroides v. crassa, M. aeruginosa and O. limosa were ranged 0.3~2.0$\times$10$^4$cells/ml, 6.4$\times$10$^2$~1.0$\times$10$^4$cells/ml and 4.6$\times$10$^3$~1.6$\times$10$^4$cells/ml, respectively. In winter, diatom Stephanodiscus was considered to be an important species whose average standing crops of Stephunodiscus was 4.9$\times$10$^2$cells/ml from November to April of the next year and the highest was 1.3$\times$10$^3$cells/ml in January.

• Environmental Analysis Health and Toxicology
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• v.18 no.2
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• pp.111-120
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• 2003

The validation of many synthetic chemicals that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, the regulation and evaluation of the chemical hazard playa very important role to environment and human health. The clastogenicity of 17 synthetic chemicals was evaluated in Chinese hamster lung fibroblast cells in vitro. 2-Nitroaniline (CAS No. 88-74-4) induced chromosomal aberrations with statistical significance at the concentration of 86.3 ${\mu}$g/ml in the absence of metabolic activation system. 1-Chloroanthraquinone (CAS No. 82-44-0) which is one of the most cytotoxic chemical among 17 chemicals tested revealed no clastogenicity in the range of 0.8 ∼ 3.0 ${\mu}$g/ml both in the presence and absence of S-9 metabolic activation system. From the results of chromosomal aberration assay with 17 synthetic chemicals in Chinese hamster lung cells in vitro, 2-Nitroaniline (CAS No. 88-74-4) revealed weak positive clastogenic results in this study.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.97-97
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• 2003

유용 수산생물인 전복, 소라, 성게 등 무척추동물의 종묘생산에 있어 부착 규조류는 수서 생태계의 일차 생산자로서 유생의 변태와 변태 후의 초기 먹이생물로 활용되고 있으며 최근에는 단일 부착규조류의 실내 배양을 통해 유용 수산생물 종묘의 대량 생산을 유도하고 있다. 부착규조류의 생물량 및 종 조성에 따라 이들 조식동물의 성장과 먹이 효율성에 커다란 영향을 끼친다. 이 연구는 종묘생산의 환경 조건과 동일한 현장에서 유수식 수조에 투명 플라스틱 부착파판(30$\times$40cm)을 설치하여 1997년 10월부터 1999년 4월까지 실내수조에 설치한 부착파판을 10일 간격으로 회수하여 부착된 규조류의 생물량과 환경적 특성을 조사하였다. 실험기간 동안 자연광을 55~75% 차단한 상태에서 실험을 진행하였고 수온과 염분은 각각 14.1$^{\circ}C$~28.6$^{\circ}C$와 32.5$\textperthousand$~35.3$\textperthousand$의 범위를 보였다. 실험기간 동안 부착규조류의 총 출현종수는 27종(17속 25종 2미동정종)으로 중심규조류(centric diatom)가 4종 그리고 우상규조류(pennate diatom)가 23종이었다. 현존량의 30% 이상을 점유하는 부착 규조류들은 Bacillaria paxillifera, Cocconeis scutellum, Diatoma hyalina, Navicula mollis, Nitzschia sp., Synedra tabulta 등 6종이 우점하였다. 부착규조류의 현존량은 2.5$\times$$10^3$~ 5.0$\times$$10^{5}$ cells $cm^{-2}$ 의 분포 범위로 1999년 4월에 가장 높고 1997년 10월에 가장 낮았다. Chlorophyll $\alpha$량 ($\mu\textrm{g}$ chl $\alpha$ $cm^{-2}$)은 0.02 ~ 1.72 $\mu\textrm{g}$ chi $\alpha$ $cm^{-2}$의 범위로써 부착규조류의 현존량과 유사한 분포 특성을 보였다. 유수식 실내수조에 부착된 부착규조류의 부착 형태, 우점종과 현존량은 배양 시기에 따라 종간 특이성을 보였다.다.

• Microbiology and Biotechnology Letters
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• v.44 no.2
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• pp.201-207
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• 2016

The aim of this study was to investigate the potential of lactic acid bacteria (LAB) strains as probiotics. Two strains were isolated from healthy chicken cecum and their acid and bile tolerance, residual organic acids, antibacterial activity against pathogenic bacteria, and immunomodulation activity were measured. Identification of the isolated strains was performed using the API 50CHL system and phylogenetic analysis using 16S rDNA sequencing. The isolates were determined to be Lactobacillus sakei strains. The acid tolerance of strains L2 and L8 was high enough that 75% of the inoculum survived in pH 2 for 2 h. The bile tolerance of both strains was observed at a 1% Oxgall concentration in MRS broth. The production of organic acids (lactic acid and acetic acid) and pH changes during growth were monitored and the maximum concentrations were obtained after 48 h of incubation. Culture supernatants of the two LAB strains showed strong antibacterial activity against pathogenic bacteria. The heat-killed LAB cells also induced high levels of immune cell proliferation compared with the control, and stimulated IL-6 and TNF-α production in mouse macrophages. Therefore, L. sakei strains L2 and L8 can be considered suitable probiotic bacteria.

• ALGAE
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• v.20 no.2
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• pp.133-140
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• 2005

Daily variation of phytoplankton community and environmental parameters were investigated at the lower Nakdong River (Mulgum) from January 2002 to December 2003 to investigate the dynamics of a phytoplankton community in detail. The daily results of water quality in this investigation showed pH (8.1 $\pm$ 0.7), DO (10.3 $\pm$ 2.7 $mg{\cdot}l^{-1}$), water temp. (18.8 $\pm$ 7.4°C), BOD (2.4 $\pm$ 1.0 $mg{\cdot}l^{-1}$), COD (5.3 $\pm$ 1.2 $mg{\cdot}l^{-1}$) and chl. a (43.5 $\pm$ 35.1 mg ${\cdot}m^{-3}$). The results of nutrient factors were the following: TN (3.1 $\pm$ 0.8 $mg{\cdot}l^{-1}$), NO3-N (2.5 $\pm$ 0.5 $mg{\cdot}l^{-1}$), TP (90 $\pm$ 48 ${\mu}g\;{\cdot}\;l^{-1}$), PO4-P (43 $\pm$ 30 ${\mu}g\;{\cdot}\;l^{-1}$). Dominant phytoplankton species during the study period were diatom (Stephanodiscus hantzschii, Aulacoseira granulata var. angustissima and A. italica) and cyanobacteria (Microcystis aeruginosa, Aphanizomenon flos-aquae). The small centric diatom, Stephanodiscus hantzschii, was repeatedly dominant from late fall to the following spring (mean and maximum cell density, 2.3 × 103 $\pm$ 3.8 × 103, 4.5 × 105 cells $ml^{-1}$, respectively). Pinnate diatom, Aulacoseira granulata var. angustissima and A. italica, were frequently observed all season except January to March. Cyanobacteria, Microcystis aeruginosa and Aphanizomenon flos-aquae, proliferated in summer of 2002 except in 2003 due to heavy precipitation. The dominant zooplankton species (March-early May) was rotifer (Brachionus, Keratella, Polyarthra) and cladocerans (Diaphanosoma). The daily observed dynamics of the phytoplankton community in the lower Nakdong River in this study may play an important role in increasing the detailed resolution of limnological information and serving as ecological data for future studies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1192-1200
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• 2004

Gamma irradiations at 5 or 10 kGy were applied to salted and fermented anchovy sauce, for improving the hygiene Quality and evaluating the genotoxicological safety. In vitro genotoxicological safety of irradiated sauces was evaluated by Salmonella Typhimurium (TA98, TA100, TAI535 and TAI537) and E. coli WP2 uvrA, reversion assay, SOS chromotest (Escherichia coli PQ37), and chromosome aberration test (Chinese hamster lung fibroblast cells) in the absence or presence of an exogenous metabolizing system (S9 mix). The gamma-irradiated samples were not significantly different from nonirradiated-control for three in vitro tests (p＜0.05). ：In vivo micronucleus test using ICR mice (male) was not significantly different from the control at p＜0.05. The salted and fermented anchovy sauce exposed to 5 or 10 kGy-gamma ray revealed negative results in these three in vitro mutagenetic tests and in vivo micronucleus test upto 50,000 $\mu$g/plate, respectively. The results indicated that 5 or 10 kGy gamma-irradiated salted and fermented anchovy sauces did not show any mutagenicity.