• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.155-161
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• 2002

Tetraselmis suecica (T. suecica) of Prasinophyta was selected because the growth rate is comparatively higher and the culturing is also easy. In order to investigate antioxidative activity, the soluble elements of T. suecica were fractionated using water and organic solvents such as methanol, hexane, chloroform, ethylacetate and butanol. The chloroform fraction of T. suecica showed strong antioxidative activity. The potential antioxidative activity was detected in hexane: ethylacetate (1:5) once used the fractions by different mixtures of organic solvents. This fraction was further purified by preparative thin layer chromatography (PTLC) and repeated reverse-phase HPLC. On the basis of chemical and spectroscopic evidences obtained by UV, FT-IR, FAB-MS and NMR, the compound purified from T. suecica was identified as pheophorbide-a. The antioxidative activity of the compound was comparable to that of $\alpha$-tocopherol and could be act as an antioxidant in foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.910-914
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• 2005

This study was to determine the inhibitory effect of ethanol extract of leaf, bark and xylem of Quercus aliena Blume and, consecutively, of organic solvent subfractions against food borne pathogens. The ethanol extracts of leaf, bark and xylem of Quercus aliena Blume were shown to have antimicrobial effect against Gram-positive and Gram-negative bacteria. Listeria monocytogenes and Salmonella Typhimurium were more resistant to ethanol extracts of the Quercus aliena Blume tissues compared with Bacillus cereus and Escherichia coli O157:H7. The ethanol extract of Quercus aliena Blume leaf showed the strongest antimicrobial activity against food borne pathogens, followed by those of xylem and bark. The ethanol extract treatment $(500\~1,000\mu g/mL)$ of Quercus aliena Blume leaf completely reduced the growth of B. cereus and L. monocytogenes within 24 hour whereas $2,000\mu g/mL$ of ethanol extract was needed for complete growth inhibition of E. coli O157:H7 and S. Typhimurium. Among organic solvent subfractions obtained from the ethanol extract of leaf, bark and xylem of Quercus aliena Blume, the ethyl acetate fraction showed the strongest antimicrobial activity, but no antimicrobial activity was observed in chloroform, hexane and water fractions.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.2
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• pp.144-150
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• 2013

Hybrid ceramic membrane (HCM) processes that combined ozonation with a ceramic membrane (CM) or a reactive ceramic membrane (RM), an iron oxide nanoparticles (IONs) incorporated-CM were investigated for membrane fouling control. Alumina disc type microfiltration and ultrafiltration membranes doped with IONs by sintering method were tested under varying mass fraction of IONs. Scanning electron microscope (SEM) images showed that IONs were well-doped on the CM surface and doped IONs were approximately 50 nm in size. Change in the pure water permeability of RM was negligible compared to that of CM. These results indicate that IONs incorporation onto CM had little effect on CM performance in terms of the flux. Natural organic matter (NOM) fouling and fouling recovery patterns during HCM processes confirmed that the RM-ozonation process enhanced the destruction of NOM and reduced the extent of fouling more than the CM-ozonation process by hydroxyl radical formation in the presence of IONs on RM. In addition, analyses of NOM in the feed water and the permeate showed that the efficiency of membrane fouling control results from the NOM degradation during HCM processes; leading to removal and transformation of relatively high contents of aromatic, high molecular weight and hydrophobic NOM fractions.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.4
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• pp.514-520
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• 2019

This study investigated the improved lipid metabolism effect of 3T3-L1 cells induced by adipocytes using the dichloromethane (DCM) fraction in the organic solvent extract of Wassong (Orostachys japonicus). To confirm the cell cytotoxicity, each of 6 fractions of organic solvent extracts (EtOH, Hexane, DCM, EtOAc, BuOH, and H₂O) was examined using MTS assay. As a result, it was confirmed that the DCM extract was stable over the whole range of concentrations, and a DCM fraction was used to confirm the improved lipid metabolism effect. Lipid excretion was measured to confirm the change of lipid metabolism. 3T3-L1 cells induced by adipocytes were treated with DCM extract and stained with oil-red O to evaluate lipid accumulation. As a result, it was confirmed that the lipid efflux was significantly improved. In order to confirm the mechanism of lipid efflux, the mRNA expressions of ABCA1 and ABCG1, which are lipid transport proteins, were confirmed by real-time PCR. Therefore, the present study confirmed that the DCM extract from Orostachys japonicus has the effect of improving the lipid metabolism on 3T3-L1 adipocytes. In addition, the results of this study will be used as the basis for the development of functional foods using Orostachys japonicus and also for conducting research on the detailed mechanisms.

• Safety and Health at Work
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• v.14 no.4
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• pp.390-397
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• 2023

Introduction: Biological risks are a major global problem in the workplace. The recent COVID-19 pandemic has highlighted the need for a more comprehensive understanding of the biological risks at work. This study presents data on both communicable infectious biological agents and noncommunicable factors leading to death and disability for the year 2021. Methods: We followed the methodology established by the International Labour Organization (ILO) in their past global estimates on occupational accidents and work-related diseases. We used relevant ILO estimates for hazardous substances and related population attributable fractions derived from literature, which were then applied to World Health Organization mortality data. The communicable diseases included in the estimates were tuberculosis, pneumococcal diseases, malaria, diarrheal diseases, other infectious diseases, neglected tropical diseases, influenza associated respiratory diseases and COVID-19. Noncommunicable diseases and injuries considered were Chronic Obstructive Diseases (COPD) due to organic dusts, asthma, allergic reactions and risks related to animal contact. We estimated death attributable to biological risk at work and disability in terms of disability adjusted life years (DALYs). Results: We estimated that in 2022, 550,819 deaths were caused by biological risk factors, with 476,000 deaths attributed to communicable infectious diseases and 74,000 deaths caused by noncommunicable factors. Among these, there were 223,650 deaths attributed to COVID-19 at work. We calculated the rate of 584 DALYs per 100,000 workers, representing an 11% increase from the previous estimate of the global burden of work-related disabilities measured by DALYs. Conclusion: This is a first update since previous 2007 ILO estimates, which has now increased by 74% and covers most biological risks factors. However, it is important to note that there may be other diseases and deaths are missing from the data, which need to be included when new information becomes available. It is also worth mentioning that while deaths caused by major communicable diseases including COVID-19 are relatively rare within the working population, absences from work due to these diseases are likely to be very common within the active workforce.

• Korean Journal of Environmental Agriculture
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• v.4 no.2
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• pp.71-77
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• 1985

Soil samples collected from paddy field adjacent to zinc-mining sites were sequentially extracted to assess chemical fractions of Cd, Zn, Cu and Pb. The purpose of this study was two fold; (i) to examine the chemical forms of heavy metal in soils by sequential extraction. and (ii) to determine relationships between the chemical distribution of heavy metal in the soil and the heavy metal content of the brown rice. The results are summarized as follows. The content of exchangeable, organically bound and carbonate Cd and residual Zn was 73.9% and 63.8% of total Cd and Zn in the soil, respectively. The content of exchangeable Cd, Zn and Pb in soil showed highly negative correlations with pH, organically bound Cd, carbonate Cd, sulfide Cd, Zn and Pb in soil showed highly positive correlations with pH. The content of organically bound Cd, Zn, Pb and carbonate Cu in soil showed highly positive correlations with organic matter content, while the content of sulfide Cu and residual Cd in soil showed highly negative correlation with organic matter content. The content of carbonate Cd, Zn, Pb and residual Cu in soil showed highly positive correlations with CEC, but the content of exchangeable Cd, Zn, Cu, Pb and organically bound Cu in soil showed highly negative correlations with CEC. The content of total, organically bound, carbonate, sulfide and residual Cd in soil were highly correlated with that of Cd in brown rice. The content of any Pb fractions in soil were not correlated with that of Pb in brown rice. The content of water soluble and exchangeable Zn in soil were highly correlated with that of Zn in brown rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.755-758
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• 2005

Wild grape is a traditional medicine plant in north-eastern part of Asia and has been known to have healing properties for various illnesses. This study was to determine the optimum extraction condition and antioxidant activity of ethanol extracts of wild grape (V. coignetiae) seed. Also, organic solvent fractions of hexane, chloroform, ethyl acetate and butanol were obtained from the ethanol extract of wild grape seed at different temperatures. Total ethanol extraction yield of wild grape seed ranged from $4\%\;to\;12\%$ depending on the ethanol concentration, extraction temperature and time condition. The highest extraction yield of $11.9\%$ was obtained at $90\%$ ethanol condition for 12 hour at $70^{\circ}C$. However, the strongest free radical scavenging effect $(RC_{50})$ with $20.93\mu g/mL$ was observed in $70\%$ ethanol extract of wild grape seed extracted for 6 hour at $70^{\circ}C,\;while\;RC_{50}\;with\;40.42$\mu g/mL$ was observed in $90\%$ ethanol extract for 12 hour at $70^{\circ}C$. Antioxidant activity of ethanol extracts of wild grape seed increased as total phenol contents increased. Among each fraction obtained from organic solvents, ethyl acetate fraction was found to have the strongest $RC_{50}\;(8.6\mu g/mL)$ and 636.77 mg GAE/g phenol contents .

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.20-34
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• 2006

This study was undertaken to assess the anthropogenic impact on trace metal concentrations (Zn, Cu, Pb, Cr, Ni, and Cd) of roadside sediments (N = 70) from No.7 national road within the watershed of Hoidong Reservoir in Pusan City and to estimate the potential mobility of selected metals using sequential extraction. We generally found high concentrations of metals, especially Zn, Cu and Pb, affected by anthropogenic inputs. Compared to the trace metal concentrations of uncontaminated stream sediments, arithmetic mean concentrations of roadside sediments were about 7 times higher for Cu, 4 times higher for Zn, 3 times higher for Pb and Cr and, 2 times higher for Ni and As. Speciation data on the basis of sequential extraction indicate that most of the trace metals considered do not occur in significant quantities in the exchangeable fraction, except for Cd and Ni whose exchangeable fractions are appreciable (average 29.3 and 25.8%, respectively). Other metals such as Zn (51.4%) and Pb (45.2%) are preferentially bound to the reducible fraction, and therefore they can be potentially released by a pH decrease and/or redox change. Copper is mainly found in the organic fraction, while Cd is highest in the exchangeable fraction, and Cr and Ni in the residual fraction. Considering the proportion of metals bound to the exchangeable and carbonate fractions, the comparative mobility of metals probably decreases in the order of Cd>Ni>Pb>Zn>Cr>Cu. Although the total concentration data showed that Zn was typically present in potentially harmful concentration levels, the data on metal partitioning indicated that Cd, Ni and Pb pose the highest potential hazard for runoff water. As potential changes of redox state and pH may remobilize the metals bound to carbonates, amorphous oxides, and/or organic matter, and may release and flush them through drain networks into the watershed of Hoidong Reservoir, careful monitoring of environmental conditions appears to be very important.

• The Korean Journal of Food And Nutrition
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• v.16 no.1
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• pp.7-14
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• 2003

This study mainly focused on to investigate the effects of Schizandra chinensis on the growth of a bacterium, CS6 which was isolated from kimchi. CS6 was final]y identified to lactobacillus plantarum that caused acidification of kimchi. The ethanolic extract of Schizandra chinensis(EES) inhibited the growth of L. plantarum. Minimum inhibition concentration of crude EES on L. plantarum was 62.5mg/$m\ell$. In broth culture, 5$\mu\textrm{g}$/$m\ell$ of EES completely inhibited the growth of L. plantarum during fermentation. The addition of 0.4% of EES has no apparent effect on quality including the taste and color on kimchi. It was expected that EES-containing kimchi could extend the period of preservation. Analysis of organic acids in water fractions of EES was carried out by HPLC. It is apparent that antimicrobial active fractions contained the highest concentration of succinic acid, a little tartaric acid and malic acid. Among these organic acids, succinic acid showed the strong inhibitory effect against L. plantarum CS6 in vitro. Succinic acid-containing kimchi with a concentration of 0.4 and 0.5% had the inhibitory effect on growth of L. plantarum. Inhibitory effect of EES on amylase, cellulase and pectinase was also tested. In conclusion, the present experiment demonstrated that EES inhibited the growth of L. plantarum, and various enzyme activity. EES-containing kimchi was sustained the hardness, and initial acidity during fermentation. EES was considered as the possible additive of kimchi process and EES added in kimchi increase the quality, and storage period of kimchi.

• Journal of Korean Society of Forest Science
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• v.48 no.1
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• pp.51-58
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• 1980

Translocation of $^{14}C$-labelled photosynthate from needles to terminal buds of Pinus elliottii was studied to understand a pattern of mobilization of photosynthate to buds during the period of female strobilus initiation. Current-year shoots of 20-year-old trees were exposed in 1ate July and late August to $50{\mu}$ Ci of $^{14}CO_2$ for 90 minutes, and harvested 1 day and 7 days after the exposure to analyze distribution of $^{14}C$ in ethanol-soluble and ethanol-insoluble fractions. Over 85% of total radioactivity of bud tissue one day after the exposure and 55% total activity seven days after the exposure remained in the ethanol-soluble fraction. The amount of $^{14}C$ translocation into female-producing buds in late August was significantly less than into vegetative and male-producing buds both one day and seven days after the exposure. When the ethanol­soluble fraction was further fractionated into hexane-soluble, amino acid, sugar, and organic acid fractions, radioactivity in the female-producing buds in late August was about a third of that in male-producing buds in all the fractions. This indicated that the male-producing buds required in late August but not in late July mobilization of large amount of photosynthate for developing male strobilus primordia. Fema1e-producing buds, on the other hand, did not mobilize as much photosynthate as male-producing buds in late August when female strobilus primordia are believed to be initiated. It is suggested that initiation of the female strobilus primordia is associated with temporary reduction in the metabolic activity of the terminal buds in slash pine.