• Korean Journal of Ecology and Environment
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• v.45 no.1
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• pp.110-122
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• 2012

This study examined the benthic diatom community distribution, land cover/use and water quality in relation to stream shape complexity (SSC) in the Seom River watershed. SSC showed a significant relation to the riparian land cover/use pattern and also water quality variables of the studied streams. Streams with high stream shape complexity (HSC) appeared to have a high proportion of forest and farmland, while streams having a low stream shape complexity (LSC) appeared to have high proportion of city. Streams with lower SSC showed higher nutrients concentration in the stream waters. Benthic diatom species composition and dominant species appeared to be similar regardless of SSC differences among the studied streams, while the variation of diatom density was manifested with SSC. The relative abundance of dominant benthic diatoms varied with SSC. Saprophilic diatoms were dominant in the streams of LSC, while saproxenic diatoms were dominant in the streams of HSC. During the evaluation of biological water quality using the benthic diatom indices, Trophic Diatom Index (TDI) and Diatom Assemblage Index to organic water pollution (DAIpo), the streams of LSC generally showed poorer water quality than those of MSC (Middle stream shape complexity) and HSC. In particular, BOD, TP, and $PO_4$-P showed significant relationships with DAIpo. In conclusion, shape complexity of streams in the Seom River watershed showed a close relation with benthic diatom distribution. This relation seemed to primarily be resulted from the effect of proximate factors, such as water quality, which might be affected by the land use types determining the degree of SSC.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.387-395
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• 2009

This study was conducted to investigate the effects of starch concentrations and heating conditions on the gel characteristics of arrowroot starch. Arrowroot starch gels with various pHs, and starch concentrations, were prepared using different temperatures and heating times, and then stored for 24 hrs at $4^{\circ}C$. The hardness of sample gels made at pH 2.0 and 4.0 increased as the starch concentration increased from 7% to 10%, with the maximum value of 94 N being obtained when the gel was prepared at pH 4.0 with a starch concentration of 10%. The maximum hardness of samples prepared with concentrations of starch ranging from 7~9% appeared at $80^{\circ}C$, regardless of the heating temperature and time. Furthermore, the hardness of samples prepared at greater than $100^{\circ}C$ was relatively lower than that of samples prepared at other temperatures. When a starch concentration of 8% was used, the degree of gelatinization(DR) increased as the heating temperature increased, with the maximum value of DR being about 76% at $120^{\circ}C$, regardless of heating time. After storage for 24 hrs, the hardness of samples prepared at $70^{\circ}C$, $80^{\circ}C$ and $90^{\circ}C$ appeared to decrease, while that of samples prepared at $100^{\circ}C$, $110^{\circ}C$ and $120^{\circ}C$ increased. The correlation between hardness and the degree of gelatinization or retrogradation was very high when samples were prepared at $80^{\circ}C$ with a starch concentration of 9%, as indicated by a correlation coefficient of greater than 0.95. Overall, the microstructures of freeze-dried arrowroot starch gel were composed of a continuous network of amylose and amylopectin with fragmented ghost structures in an excluded phase, but these ghost structures were more evident after storage and with increased heating temperature.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.101-108
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• 2014

This study was conducted in order to compare the biological activities of water extracts and sugar immersion extracts of green pepper (Capsicum annuum L.), purslane (Portulaca oleracea L.) and shiitake (Lentinula edodes (Berk.) Pegler) by measuring total polyphenol and flavonoid contents, antioxidant activities and inhibitory effects on ${\alpha}$-amylase and ${\alpha}$-glucosidase. The contents of total polyphenols and flavonoids were higher in water extracts than in sugar immersion extracts. The anti-oxidative activities of water and sugar immersion extracts were measured using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity assay and reducing power assay. All extracts scavenged radicals in a concentration-dependent manner, and water extracts showed stronger radical scavenging activity and reducing power than sugar immersion extract. However, they all exhibited lower activities than ascorbic acid. Compared to the anti-diabetic drug acarbose, which was used as a positive control, the two types of extracts exhibited low ${\alpha}$-glucosidase inhibitory activities, although the activity of sugar immersion extracts were 2-fold higher than that of water extracts. ${\alpha}$-Amylase inhibitory action was not observed for any of the extracts. Finally, by cytotoxicity test, we confirmed that sugar immersion extracts were safer than water extracts. These results indicate that water extracts and sugar immersion extracts of green pepper, purslane and shiitake have different advantages in terms of their antioxidant and anti-diabetic effects, respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.3
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• pp.235-241
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• 2009

In this study, the antioxidative effects, inhibitory effects on tyrosinase, elastase of Persicaria perfoliata extracts were investigated. The deglycosylated fraction of extract ($12.38{\mu}g$/mL) showed the most prominent free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of P. perfoliata extracts on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of extract ($0.35{\mu}g$/mL) showed the most prominent ROS scavenging activity. The protective effects of P. perfoliata extract/fractions on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The P. perfoliata extracts suppressed photohemolysis in a concentration dependent manner ($1{\sim}50{\mu}g$/mL) except the deglycosylated fraction of extract. The inhibitory effect of P. perfoliata extracts on tyrosinase was investigated to assess their whitening efficacy. Inhibitory effects ($IC_{50}$) on tyrosinase were determined with ethyl acetate fraction of P. perfoliata extract ($136.00{\mu}g$/mL) and deglycosylated fraction of extract ($68.10{\mu}g$/mL). Finally, their anti-elastase activities were measured to predict the anti-wrinkle efficacy in the human skin. Inhibitory effects ($IC_{50}$) on elastase were determined with ethyl acetate fraction of P. perfoliata extract ($67.20{\mu}g$/mL) and deglycosylated fraction of extract ($43.50{\mu}g$/mL). These results indicate that extract/fractions of P. perfoliata can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS. Extract/fractions of P. perfoliata can be applicable to new functional cosmetics for antioxidant, antiaging.

• 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).

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.2
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• pp.124-134
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• 2005

To investigate the exposure effect of polynuclear aromatic hydrocarbons (PAHs), we measured airborne total PAHs as an external dose, urinary 1-hydroxypyrene (1-OHP) as an internal dose of PAHs exposure, and analyzed the relationship between urinary 1-OHP concentration and PAHs exposure. The study population contained 44 workers in steel-pipe coating and paint manufacture industries. The airborne PAHs was obtained during survey day, and urine were sampled at the end of shift. Personal information on age, body weight, height, eniployment duration, smoking habit, and alcohol consumption was obtained by a structured questionnaire. Airborne PAHs were analyzed by the gas chromatograph with mass selective detector. Urinary 1-OHP levels were analyzed by the high performance liquid chromatograph with ultraviolet wavelength detector. For statistical estimation, t-test, ${\chi}^2$-test, analysis of variance, correlation analysis, arid regression analysis were executed by SPSS/PC (Windows version 10). The mean of environmental total PAHs was $87.8{\pm}7.81{\mu}g/m^3$. The mean concentration ($526.5{\pm}2.85{\mu}g/m^3$) of workers in steel-pipe coating industries using coal tar enamel was the higher than that ($17.5{\pm}3.36{\mu}g/m^3$) of workers in paint manufacture industries using coal tar paint. The mean of urinary 1-OHP concentration ($51.63{\pm}3.144{\mu}\;mol/mol$ creatinine) of workers in steel-pipe coating industries was the higher than that ($2.33{\pm}4.709{\mu}\;mol/mol$ creatinine) of workers in paint manufacture industries. The mean of urinary 1-OHP concentration of smokers was the higher than that of non-smokers. There was significant correlation between the urinary concentration of 1-OHP and the environmental concentration of PAHs (r=O.S48, p<0.001), pyrene(r=0.859, p<0.001), and urinary cotinine (r=0.324, p<0.05). The regression equation between the urinary concentration of 1-OHP in ${\mu}g/g$ creatinine($C_{1-OHP}$) and airborne concentration of PAHs (or pyrene) in ${\mu}g/m^3$ ($C_{PAHs}$ or Cpyrene) is: Log ($C_{1-OHP}$)=-0.650+0.889×Log($C_{PAHs}$), where $R^2=0.694$ and n=38 for p<0.001.Log ($C_{1-OHP}$)=1.087+0.707${\times}$Log(Cpyrene), where $R^2=0.713$ and n=38 for p<0.001. From the results of stepwise multiple regression analysis about 1-OHP, significant independents were total PAHs and urinary cotinine (adjusted $R^2=0.743$, p<0.001). In this study, there were significant correlation between the urinary concentration of 1-OHP and the airborne concentration of PAHs. The urinary 1-OHP was effective index as a biomarker of airborne PAHs in workplace. But it was influenced by non-occupational PAHs source, smoking.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.1
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• pp.17-24
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• 1994

The urinary excretion of ${\delta}$-aminolevulinic acid has been widely used as a measure of the biological effect of lead in lead exposed workers. It is usually measured by colorimetric method based on the color reaction of ALA-pyrrole with Ehrlich's reagent. But the results of ${\delta}$-ALA in urine by this method are somewhat artificially higher than expected due to the urinary ALA-like compound such as aminoacetone. On the other hand, the recently developed fluorometric HPLC method is very sensitive and specific for the measuring urinary ALA. In order to compare the data obtained by two methods and to investigate the interrelation between two methods, 117 lead workers with different lead exposure were checked urinary ${\delta}$-ALA, blood lead and other lead exposure related indices. The results obtained are as follows; 1. Urinary excretion of ${\delta}$-ALA by colorimetric method is 2.15 times higher than HPLC method in overall, revealing 2.47 times in workers of blood lead less than $20{\mu}g/dl$, 2.53 times in workers of blood lead $21-40{\mu}g/dl$ and 1.86 times in workers of blood lead over $41{\mu}g/dl$, respectively. 2. While the correlation coefficients of ${\delta}$-ALA measured by colorimetric method with blood lead and blood ZPP was 0.571 and 0.629, those of ${\delta}$-ALA measured by HPLC with blood lead and blood ZPP were 0.6l0 and 0.637. All the correlation coefficients were statistically significant, but there was no statistical difference of correlation coefficients between two methods. 3. The correlation coefficient of urinary excretion of ${\delta}$-ALA between two method was 0.838 without any correction, but it was 0.852 with the correction of specific gravity 1.024. 4. Simple linear regression of ${\delta}$-ALA measured by HPLC method on ${\delta}$-ALA measured by colorimetric method was (ALA-UPH)=-0.245+0.536 (ALA-UCO) without any correction and it was (SP ALA)=-0.525+0.598 (SP ALA-UCO) with the correction of specific gravity 1.024. With above results, it is recommended that the diagnostic criteria of ${\delta}$-ALA for lead poisoning needed to be revised if ${\delta}$-ALA is measured by HPLC rather than colorimetric method.

• Progress in Medical Physics
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• v.9 no.4
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• pp.227-245
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• 1998

A most appropriate model of 3-D conformal radiotherapy has been induced by clinical evaluation and animal study, and therapeutic gains were evaluated by numerical equation of tumor control probability(TCP) and normal tissue complication probability (NTCP). The radiation dose to the tumor and the adjacent normal organs was accurately evaluated and compared using the dose volume histogram(DVH). The TCP and NTCP was derived from the distribution of given dosage and irradiated volume, and these numbers were used as the biological index for the assessment of the treatment effects. Ten patients with liver disease have been evaluated and 3 dogs were sacrificed for this study. Based on the 3-D images of the tumor and adjacent organs, the optimum radiation dose and the projection direction which could maximize the radiation effect while minimizing the effects to the adjacent organs could be decided. 3). The most effective collimation for the normal adjacent organs was made through the beams eye view with the use of multileaf collimator. When the dose was increased from 50Gy to 70Gy, the TCP for the conventional 2-port radiation and the 5-port multidimensional therapy was 0.982 and 0.995 respectively, while the NTCP was 0.725 and 0.142 respectively, suggesting that the 3-D conformal radiotherapy might be the appropriate therapy to apply sufficient radiation dose to the tumor while minimizing the damages to the normal areas of the liver. Positive correlation was observed between the NTCP and the actual complication of the normal liver in the animal study. The present study suggest that the use of 3-D conformal radiotherapy and the application of the mathematical models of TCP and NTCP may provide the improvements in the treatment of hepatoma with enhanced results.

• Journal of Mushroom
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• v.3 no.2
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• pp.79-84
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• 2005

The research for incubation period, mycelial density, day required for primordial formation after inoculation(below DPI), number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 100, 200, 300, 400, 500(${\mu}g/50g$) of $Na_2SeO_3$ is following. Incubation periods of P. cornucopiae are 20~23 days per each low concentration treatment with $Na_2SeO_3$. Compared to the control which took 22 days of incubation period, it is reduced 1 or 2 days. Mycelial density of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $500{\mu}g/50g$ is very compact. DPI of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ was reduced 1 or 2days, but $500{\mu}g/50g$ was increased 1 day. Number of valid stipes of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ is between 19 and 20. It was increased 1 or 2, as compared to 18 of control, but $500{\mu}g/50g$ was reduced to 1. Individual weight of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ was between 129 and 138g/850cc. It was increased 4.9~12.2% as compared to 123g/850cc of the control but $500{\mu}g/50g$ was 122g/50g. Accumulation amount of organic selenium for P. cornucopiae treated with $Na_2SeO_3$ between 100 and $500{\mu}g/50g$ was $2.73{\sim}8.19{\mu}g/g/dry$. It was increased 55~164 times as the concentration increased when compared to $0.05{\mu}g/g/dry$ of the control. In conclusion, incubation period, mycelial density, DPI, number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 100, ${\sim}400{\mu}g$ of $Na_2SeO_3$ was increased, but $500{\mu}g/50g$ was reduced. So more than $500{\mu}g/50g$ concentration treatments are required research.

• Journal of Mushroom
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• v.3 no.2
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• pp.85-89
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• 2005

The research for incubation period, mycelial density, day required for primordial formation after inoculation(below DPI), number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 600, 700, 800, 900, 1000(${\mu}g/50g$) of $Na_2SeO_3$ is following. Incubation periods of P. cornucopiae are 25~30 days per each treatment with $Na_2SeO_3$. Compared to the control which took 22 days of incubation period, it is increased 3 or 8 days for the treatment of $600{\sim}1000{\mu}g/50g$. Mycelial density of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ is very similar with control. DPI of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was increased 3 or 8 days. Number of valid stipes of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was between 10 and 16. It was decreased 2 or 8 as compared to 18 of control. Individual weight of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was between 94 and 116g/850cc. It was decreased 5.7~23.5% as compared to 123g/850cc of the control. Accumulation amount of organic selenium for P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was $9.1{\sim}10.8{\mu}g/g/dry$. It was increased 182~216 times as the concentration increased when compared to $0.05{\mu}g/g/dry$ of the control. In conclusion, incubation period, mycelial density, DPI, number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating $600{\sim}1000{\mu}g/g$ of $Na_2SeO_3$ was decreased. So that the optimal treatment was less $400{\mu}g/g$ than $600{\sim}1000{\mu}g/g$.