• Food Science and Preservation
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• v.16 no.2
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• pp.179-185
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• 2009

To develop an Enoki mushroom packaging method, mushrooms were stored at $1^{\circ}C$ for 12 days after passive MAP packaging(PM), vacuum packaging(VM), and gas flushing packaging(AM), after investigation of film thickness influences on respiration rates and gas compositions(LDPE films 20, 40, and 60 m in thickness were tested). Enoki mushrooms had respiration rates of 26.4 mL $CO_2/kg/hour$ at $0^{\circ}C$, 80.0 mL $CO_2/kg/hour$ at $10^{\circ}C$, 130.9 mL $CO_2/kg/hour$ at $20^{\circ}C$, and 130.9 mL $CO_2/kg/hour$ at $30^{\circ}C$. A film thickness of 20 m was chosen for further tests to maintain the oxygen concentration above the minimum growth level; the thinnest film offered a higher gas transmittance rate than did the thicker films. No anaerobic respiration was evident over 12 days of storage using any packaging method, with the exception of VM. AM, using a high concentration of $CO_2$, restricted respiration rate. Mushrooms packaged using the VM method showed the greatest weight loss and extent of discoloration among the packaging methods tested, followed by AM mushrooms using 50% $CO_2/10%\;O_2/40%\;N_2$. Mushrooms packaged by the VM and PM methods developed a serious off-flavor after 2 days of storage, and a high stipe elongation rate after 5 days of storage, respectively. However, AM using 50% $CO_2/10%\;O_2/40%\;N_2$ of various gas ratios tested, allowed Enoki mushrooms to be maintained for up to 12 days without development of off-flavor, discoloration, or moldiness.

• Journal of the Korean Geotechnical Society
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• v.30 no.6
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• pp.23-39
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• 2014

An artificial rainwater reservoir installed in urban areas for recycling rainwater is an eco-friendly facility for reducing storm water effluence. However, in order to recycle the rainwater directly, the artificial rainwater reservoir requires an auxiliary system that can remove non-point source pollutants included in the initial rainfall of urban area. Therefore, the conventional soil filtration technology is adopted to capture non-point source pollutants in an economical and efficient way in the purification system of artificial rainwater reservoirs. In order to satisfy such a demand, clogging characteristics of the sand filter layers with different grain-size distributions were studied with real non-point source pollutants. For this, a series of lab-scale chamber tests were conducted to make a prediction model for removal of non-point source pollutants, based on the clogging theory. The laboratory chamber experiments were carried out by permeating two types of artificially contaminated water through five different types of sand filter layers with different grain-size distributions. The two artificial contaminated waters were made by fine marine-clay particles and real non-point source pollutants collected from motorcar roads of Seoul, Korea. In the laboratory chamber experiments, the concentrations of the artificial contaminated water were measured in terms of TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) and compared with each other to evaluate the performance of sand filter layers. In addition, the accumulated weight of pollutant particles clogged in the sand filter layers was estimated. This paper suggests a prediction model for removal of non-point source pollutants with theoretical consideration of the physical characteristics such as the grain-size distribution and composition, and change in the hydraulic conductivity and porosity of sand filter layers. The lumped parameter ${\theta}$ related with the clogging property was estimated by comparing the accumulated weight of pollutant particles obtained from the laboratory chamber experiments and calculated from the prediction model based on the clogging theory. It is found that the lumped parameter ${\theta}$ has a significant influence on the amount of the pollutant particles clogged in the pores of sand filter layers. In conclusion, according to the clogging prediction model, a double-sand-filter layer consisting of two separate layers: the upper sand-filter layer with the effective particle size of 1.49 mm and the lower sand-filter layer with the effective particle size of 0.93 mm, is proposed as the optimum system for removing non-point source pollutants in the field-sized artificial rainwater reservoir.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.172-183
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• 1999

Background: Nitric oxide is a short-lived effector molecule derived from L-arginine by the nitric oxide synthase(NOS). Nitric oxide plays a role in a number of physiologic and pathophysiologic functions including host defense, edema formation, and regulation of smooth muscle tone. Some kinds of cells including macrophage are known to produce large quantities of nitric oxide in response to inflammatory stimuli such as interleukin-$1\beta$(IL-$1\beta$), tumor necrosis factor-$\alpha$(TNF-$\alpha$), interferon-$\gamma$(IFN-$\gamma$) and lipopolysaccharide(LPS). Reactive oxygen species are also known to be important in the pathogenesis of acute cell and tissue injury such as acute lung injury model Methods: Using the RA W264.7 cells, we have examined the ability of oxidant hydrogen peroxide($H_2O_2$) to stimulate nitric oxide production and inducible NOS mRNA expression. Also, we have examined the effects of NOS inhibitors and antioxidants on $H_2O_2$ induced nitric oxide production. Results: Stimulation of RAW264.7 cells with combinations of 100 ng/ml IL-$1\beta$, 100 ng/ml TNF-$\alpha$, and 100 U/ml IFN-$\gamma$ or 100 U/ml IFN-$\gamma$ and $1{\mu}g/ml$ LPS induced the synthesis of nitric oxide as measured by the oxidation products nitrite($NO_2^-$) and nitrate($NO_3^-$). Addition of $250 {\mu}M-2$ mM $H_2O_2$ to the cytokines significantly augmented the synthesis of $NO_2^-$ and $NO_3^-$(p<0.05). When cells were incubated with increasing concentrations of $H_2O_2$ in the presence of IL-$1\beta$, TNF-$\alpha$ and IFN-$\gamma$ at constant level, the synthesis of $NO_2^-$ and $NO_3^-$ was dose-dependently increased(p<0.05). $N^G$-nitro-L-arginine methyl ester(L-NAME), dose dependently, significantly inhibited the formation of $NO_2^-$ and $NO_3^-$ in cells stimulated with LPS, IFN-$\gamma$ and $H_2O_2$ at constant level(p<0.05). Catalase significantly inhibited the $H_2O_2$-induced augmentation of cytokine-induced $NO_2^-$ and $NO_3^-$ formation(p<0.05). But, boiled catalase did not produce a significant inhibition in comparison with the native enzyme. Another antioxidant 2-mercaptoethanol and orthophenanthroline dose-dependently suppressed $NO_2^-$ and $NO_3^-$ synthesis(p<0.05). Northern blotting demonstrated that H:02 synergistically stimulated the cytokine-induced iNOS mRNA expression in RA W264.7. Conclusion: These results suggest that $H_2O_2$ contributes to inflammatory process by augmenting the iNOS expression and nitric oxide synthesis induced by cytokines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1043-1053
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• 2013

We investigated the ability of soybean curd residue (SCR) and its fermented products to inhibit obesity and improve the blood lipid profiles of obese mice fed a high-fat diet. Samples were prepared by fermenting SCR with Aspergillus oryzae var effuses KACC 44990 (ASCR), a microbe used for the fermentation of traditional Korean Meju, and with Monascus pilosus IFO 4480 (MSCR), a microbe used for the production of red rice. In addition, AMSCR, a mixture composed of equal amounts of ASCR and MSCR, was also prepared. Male mice were divided into six groups and fed with either a normal diet, a high-fat diet, or a high-fat diet supplemented with SCR, ASCR, MSCR, or AMSCR. After 8 weeks, body weight gain, serum and hepatic lipid profiles, and the activities of enzymes that generate or scavenge reactive oxygen species (ROS) were evaluated. Compared with the high-fat diet group, all the test groups showed a significant reduction in body, organ, and epididymal fat weight gain. These effects were observed with supplements in the order AMSCR>ASCR>MSCR>SCR. Similarly, supplements of test samples reduced high levels of serum and hepatic triglycerides (TG), total cholesterol, and low-density lipoprotein (LDL) cholesterol caused by hight-fat diet, while high-density lipoprotein (HDL) cholesterol was increased. Interestingly, the ability of ASCR to lower serum TG was stronger than that of MSCR, while MSCR showed a stronger hypocholesterolemic effect than ASCR. Meanwhile, AMSCR returned comprehensively serum lipid levels to normal. In addition, hepatic damage was prevented with effects in the order AMSCR>ASCR>MSCR>SCR. Hepatic ROS generating system including xanthine oxidase (XO) and ROS scavenging system including superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione S-transferase (GST) were recovered to normal level by all test diets. In conclusion, this study suggests that SCR and its fermented products can inhibit obesity and improve lipid profiles.

• Tuberculosis and Respiratory Diseases
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• v.52 no.6
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• pp.616-626
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• 2002

Background : The present study was performed to further improve our understanding of molecular mechanisms involved in the activation of NFkB, a major transcriptional factor involved in the inflammatory response in the lung, by particulate matter in lung epithelial cells with an aerodynamic diameter of less than $2.5{\mu}m$(PM2.5). Materials and Methods : Immediate production of reactive oxygen species (ROS) and nitrogen species (RNS), with the PM2.5 induced expression of inducible nitric oxide synthase (iNOS), $I{\kappa}B$ degradation and $NF{\kappa}B$-dependent transcriptional activity, in 549 cells, were monitored. Addition, we also examined the effect of the iNOS inhibitor, L-N6-(1-iminoethyl) lysine hydrochloride (L-NIL), on the PM2.5-induced $NF{\kappa}B$ activation in A549 cells. Results : The rapid degradation of $I{\kappa}B$ and the increase of transcriptional activity of the $NF{\kappa}B$-dependent promotor were observed in A549 cells exposed to PM2.5. The immediate production of ROS in response to PM2.5 in A549 cells was not clearly detected, although immediate responses were observed in RAW264.7 cells. A 549 cells, cultured in the presence of PM2.5, produced an increase in NO, which was noticeably significant after 15 min of exposure with the expression of iNOS mRNA. The addition of L-NIL, an iNOS inhibitor, significantly inhibited the PM2.5-induced $I{\kappa}B$ degradation and the increase of the $NF{\kappa}B$-dependent transcriptional activity. Conclusion : These results suggest that PM2.5 stimulates the immediate production of RNS, leading to the activation of $NF{\kappa}B$ in the pulmonary epithelium.

• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.60-64
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• 2014

These studies were conducted to identify the effects of non-perforated breathable package film on storability at $1^{\circ}C$, $8^{\circ}C$, and $20^{\circ}C$ storage of 'Fuji' apples. The fresh weight loss rate was less than 2.0% in all non-perforated breathable films at three different storage periods and temperatures, $1^{\circ}C$; 210 days, $8^{\circ}C$; 75 days, and $20^{\circ}C$; 30 days except for the perforated film. 1,300 cc ($1^{\circ}C$), 5,000 cc ($8^{\circ}C$), and 10,000 cc ($20^{\circ}C$) films were closed at the optimum MA storage condition by carbon dioxide and oxygen concentration. Ethylene concentration was lowest at the 40,000 cc film in every temperatures during storage. The 1,300 cc film established higher result in soluble solid and vitamin C content than any other films at $1^{\circ}C$, also showed higher in visual quality by panel test. The 5,000 cc film had the best results on soluble solid and off-flavor in $8^{\circ}C$. In the $20^{\circ}C$ storage after 30 days of treatment the 10,000 cc film had highest firmness and visual quality. Following these results, it come to conclusion the suitable type of non-perforated breathable film such as 1,300 cc at $1^{\circ}C$, 5,000 cc at $8^{\circ}C$, and 10,000 cc at $20^{\circ}C$ for MA storage in 'Fuji' apples.

• Journal of Life Science
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• v.30 no.10
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• pp.877-885
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• 2020

Lentinuls edodes has been used for traditional food and medicine around Asia, and a variety of biological effects have been reported. In this study, L. edodes water extract (LWE) was investigated for its anti-photodamage effect in HaCaT keratinocytes. To perform the necessary assays, L. edodes was extracted with distilled water for 8 hr at 40℃ in an extract tank. Anti-photodamage activity was assessed using a scratch wound healing assay, cell proliferation, and a reactive oxygen species (ROS) scavenging test and by measuring the mRNA and protein expression levels of matrix metalloproteinases (MMPs) and type I procollagen. MMPs and collagen expression are major markers of UV-induced photodamage in skin. Prior to photodamage analysis, the total polyphenol and β-glucan contents of the LWE were evaluated and found to be 4.64 mg GAE/g DW and 165.96 mg/g, respectively. Treatment with LWE induced cell migration and cell proliferation in UV-irradiated HaCaT cells, and LWE effectively scavenged the ROS induced by H₂O₂ and UVB irradiation in HaCaT cells. UVB irradiation induced ROS generation and led to increased production of MMP-1 and MMP-9 and to decreased collagen production in human keratinocytes. Treatment with LWE upregulated the expression levels of MMP-1, MMP-9, and type I procollagen in UVB-irradiated HaCaT cells. This study suggests that LWE could be used to develop cosmetic materials with anti-photodamage effects.

• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.322-335
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• 2003

Nutrient fluxes and sediment oxygen demands (SOD) were measured with intact sediment cores collected from three stations in the downstream of Nagdong River. The sediments were subjected to controlled oxic and hypoxic conditions and temperature gradients (from $10^{\circ}C$ to $30^{\circ}C$) of the overlying waters in laboratory batch system. The effect of temperature and labile layer thickness of the sediment on SOD were examined. $PO_4\;^{3-}$ and $NH_4\;^+$ fluxes were elevated above $20^{\circ}C$ and large mobilities were observed when they were coupled with a hypoxic and high-temperature condition. In the well oxygenated conditions, $PO_4\;^{3-}$ fluxes were negative or negligible but $NH_4\;^+$ fluxes ranged from 1.3 mg N $m^{-2}\;hr^{-1}$ to 2.3 $m^{-2}\;hr^{-1}$. Temperature quotients($Q_{10}$) of $PO_4\;^{3-}$ fluxes were 3.7 ${\sim}$ 7.3 ranges to have the most high values. $PO_4\;^{3-}$ and $NH_4\;^+$ fluxes had the logarithmic increase with temperature, while $NO_3\;^-$ was negatively absorbed to the sediment and linearly correlated with the temperature. $SiO_2$ fluxes showed no difference among oxic and hypoxic conditions and sediment texture. The nutrient fluxes would be closely correlated with pore water chemistry of sediments and activated by the top sediment layer composition such as labile organic matters or algal detritus. The ecological implications of the nutrient fluxes were discussed in terms of sources and sinks of nutrients coupled to algal productions in the Nagdong River.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.184-190
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• 2016

We investigated the antioxidative and protective effects of corn silk (Zea mays L.) ethanol extracts on human HaCaT cells and erythrocytes. The NICS-2 fraction, extracted from corn silk, exhibited favorable 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activities with $IC_{50}$valuesof$13.3{\pm}0.3{\mu}g/mL$ and $14.2{\pm}0.1{\mu}g/mL$ when compared with those of ${\alpha}$-tocopherol, a positive control, with $IC_{50}=10.4{\pm}02.2$ and $22.2{\pm}3.6{\mu}g/mL$, respectively. In addition, we investigated skin protection effects of NICS extracts of corn silk in HaCaT keratinocytes. To investigate the pharmacological potential of NICS-1 and NICS-2 extracts of corn silk on UV-B-induced damage in HaCaT cells, we measured the activity of interleukin (IL) 1a. Our results showed that all the corn silk extracts inhibited the UV-B-induced activity of IL-1a. In particular, NICS-1 extracts of corn silk significantly suppressed IL-1a activity in a dose-dependent manner without inducing cytotoxicity. These results indicate that the ethanol extracts of corn silk (Zea mays L.) could function as natural cytoprotective agents and antioxidants in biological systems, particularly the skin exposed to UV radiation, by protecting cellular membrane against reactive oxygen species (ROS).

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.320-328
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• 2016

This study was conducted to provide important basic information about effective management of the marine environment at major inflow streams in Lake Andong and Lake Imha. The investigation was conducted 8 times from May, 2015 (AD1, AD2, IH1, IH2) to September, 2016 (AD3, AD4, IH3, IH4), and 8 surveyed sites were selected at Lake Andong (4 sites) and Lake Imha (4 sites). The inquiry identified 114 species, $59,913.7inds.\;m^{-2}$ in Lake Andong and 112 species, $39,038.4inds.\;m^{-2}$ in Lake Imha. The results indicate that the number of species and individuals in Lake Andong is more than that in Lake Imha, because Lake Andong has a variety of riparian vegetation and a richness of organic materials. Community analysis at Lake Imha revealed a dominant index of 0.57 (${\pm}0.18$), a diversity index of 2.87 (${\pm}0.31$), an evenness index of 0.73 (${\pm}0.04$), and a richness index of 4.17 (${\pm}0.71$). The results of functional feeding group analysis showed that a high proportion of species and individuals are gathering collectors. The results of functional habitat group analysis showed that a high proportion of species and individuals are clingers. The result of a physico-chemical water assay and dissolved oxygen and electric conductivity tests revealed that these measures increased when the water temperature decreased. The result of Pearson's correlation analysis by biological factors and physico-chemical factors showed that species and electric conductivity are highly correlated with one another. Major inflow streams of Lake Andong and Lake Imha were exposed to various point pollution sources and non-point pollution sources. This implies a necessity for continuous monitoring of the aquatic ecosystems in order to effect systematic water quality management of Lake Andong and Lake Imha.