• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.337-341
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• 2022

In this study, the effect of the combined use of a lipid-soluble n-hexane extract of red ginseng marc (HERGM) and water-soluble arginine, which exhibits anticaries activity, on the growth of Streptococccus mutans was investigated. As a result of checkerboard assay, HERGM and arginine showed a synergistic effect in inhibiting the growth of S. mutans with a fractional inhibitory concentration index of 0.396. Combination treatments of HERGM and arginine resulted in leakage of nucleic acid components and decrease in the viable cell counts of S. mutans, all of which were proportional to the concentration of HERGM. In conclusion, the synergistic effect of HERGM and arginine on the growth inhibition of S. mutans is mainly attributed to HERGM.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.400-401
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• 2003

Atmospheric fine aerosol particles play an important role in controlling a number of atmospheric processes, such as the deposition of different compounds, the optical properties etc. (Molnar et al., 1999). In this report, water-soluble species of PM$_{2.5}$ obtained from simultaneous measurements at four Asia sites (Beijng (39.56$^{\circ}$N, 116.17$^{\circ}$E), China; Gwangju (35.10$^{\circ}$N, 126.53$^{\circ}$E), South Korea; Kyoto (35.01$^{\circ}$N, 135.44$^{\circ}$E), Japan; and Ulan-Bator (47.55$^{\circ}$N, 106.52$^{\circ}$E), Mongolia) during the periods of 14-22 August, 30 October-06 November 2000, 14-21 January 2001, 23 July-02 August and 05-16 November 2002, within the framework of an APN (The Asia-Pacific Network for Global Change Research) project are reported. Ion components in 23 July-02 August 2002 were not obtained because of the technical problem of equipments.s.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.3
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• pp.191-197
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• 1992

In order to investigate the chemical components of acid precipitation at Kangwha near the Yellow Sea and Seoul in Korea, the precipitation samples were collected by wetonly precipitation sampler from February 1991 to January 1992, and pH, electric conductivity(E. C.) and major water-soluble ionic components were analyzed. Strong negative linear correlations were observed between the rainfall amount and the sum of major ionic components in $\mu eq/\ell$ at two sites. The sum of major ionic components also correlated negatively with rain intensity. The analytical results of precipitation samples at two sites were compared each other. Average values of volume-weighted pH were found to be 5.21 at Kangwha and 5.09 at Seoul. The cationic abundance($\mu eq/\ell$) in rainwater showed the general trend $NH_4^+ > Na^+ > Ca^{2+} > Mg^{2-+} > H^+ > K^+$ at Kangwah and $NH_4^+ > Ca^{2+} > Na^+ > H^+ > Mg^{2+} > K^+$ at Seoul. The anionic abundance showed the general trend $SO_4^{2-} > Cl^- > NO_3^-$ at Kangwha and $SO_4^{2-} > NO_3^- > Cl^-$ at Seoul. The concentrations of seasalt such as $Na^+ and Cl^-$ were higher at Kangwha than Seoul. The concentrations of $nss-SO_4^{2-}, nss-Cl^- and NO_3^-$ which are acid composition were higher at Seoul(96.3 $\mu eq/\ell$) than Kangwha(69.0 $\mu eq/\ell$). The contribution of seasalt to the composition of precipitation were higher at Kangwha(34.1%) than Seoul(15.7%). Ammonia and calcium species in rainwater at Kangwha and Seoul are interpreted to have 91% of neutralizing capacity of the original sulfuric and nitric acids. Provided that the precipitation acidity originates primarily from sulfate and nitrate, sulfate was found to contribute about 73-75% of the free precipitation acidity.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.E4
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• pp.177-186
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• 2003

The total of 1,454 aerosol samples were collected by high volume tape sampler at the Gosan Site in Jeju Island from 1992 to 1999, and the major water-soluble ionic components were chemically analyzed. The mean concentrations of nss-S $O_4$$^{2-}$, N $H_4$$^{＋}$, and N $O_3$$^{[-10]}$ showed high values, which were 6.73, 1.45, and 1.45 ${\mu}{\textrm}{m}$/㎥, respectively, while $Ca^{2+}$ and $K^{+}$ concentrations were low with the values of 0.49 and 0.42 $\mu\textrm{g}$/㎥. The concentrations of most components increased in spring but decreased in summer, especially with the remarkable increase of $Ca^{2+}$ and N $O_3$$^{[-10]}$ concentrations in spring. The seasonal comparison of nss-S $O_4$$^{2-}$ concentrations showed higher values with the order of spring > fall 〉 winter〉 summer, but spring 〉 winter〉 fall 〉 summer for N $O_3$$^{[-10]}$ Meanwhile, the concentration levels of N $a^{+}$ and C $l^{[-10]}$ increased more in winter season. According to the investigation of wind direction effect, the concentrations of most aerosol ionic components showed higher values consistently at the westerly and northerly wind conditions. Based on the factor analysis, the atmospheric aerosols in the Gosan Site are considered to be largely affected by marine sources, followed by anthropogenic and soil sources.urces..

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.3
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• pp.263-273
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• 2003

P $M_{2.5}$ fine particles have been collected at the Cosan measurement station in Jeju Island, and the major water-soluble components have been analyzed in order to Investigate the aerosol compositions and pollution characteristics. The mean concentrations of the components were in the order of S $O_4$$^{2-}$> N $H_4$$^{+}$> N $O_3$$^{[-10]}$ > N $a^{+}$> $K^{+}$>C $l^{[-10]}$ >C $a^2$$^{+}$>M $g^2$$^{+}$. The major components were S $O_4$$^{2-}$, N $H_4$$^{+}$ and N $O_3$$^{[-10]}$ , whose compositions were 58％, 18％ and 10％ of the total ions, respectively. Most of the components showed higher concentrations in spring season, and especially $Ca^2$$^{+}$, N $O_3$$^{[-10]}$ and S $O_4$$^{2-}$ concentrations were increased 2.8, 1.9 and 1.2 times higher than the annual mean concentrations. The most parts of S $O_4$$^{2-}$ and N $H_4$$^{+}$ were distributed in fine particles below 2.1 ${\mu}{\textrm}{m}$ size, but the $Ca^2$$^{+}$, N $a^{+}$ and C $l^{[-10]}$ showed relatively higher concentrations in coarse particles. Based on the factor analysis, the P $M_{2.5}$ fine particles were considered to be largely influenced by anthropogenic sources, and followed by sea salt and soil sources. In the variations of concentrations as a function of wind direction, most components have shown higher concentrations notably as the northwesterly prevails.thwesterly prevails.

• Journal of Environmental Impact Assessment
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• v.15 no.3
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• pp.227-235
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• 2006

In order to understand chemical characteristics and formation of dewfall in Miryang area, we analysed monthly distribution of dewfall, and investigated its chemical composition of dewfall. The modified teflon plate ($1m{\times}1m$) was used qualitatively to collect water soluble components at Miryang weather station from August 2002 to April 2003. Dewfall amount during the sampling periods (37 day) collected 5.28 mm. The behaviors of water soluble ions in dewfall showed the highest concentration ($555.8{\mu}eq/l$ for $Cl^-$, $338.6{\mu}eq/l$ for ${NO_3}^-$, $1118.2{\mu}eq/l$ for ${SO_4}^{2-}$, $262.7{\mu}eq/l$ for ${NH_4}^+$, $1341.0{\mu}eq/l$ for ${Ca_2}^+$, $177.8{\mu}eq/l$ for ${Mg_2}^+$, and $325.5{\mu}eq/l$ for $Na^+$) during the April, the lowest concentration ($243.6{\mu}eq/l$ for ${SO_4}^{2-}$, $39.3{\mu}eq/l$ for ${NH_4}^+$ and $456.2{\mu}eq/l$ for ${Ca_2}^+$) during the September. Monthly equivalent ratio of [${SO_4}^{2-}$]/[${NO_3}^-$] showed the highest value (6.45) during the March, the lowest value (1.86) during the September, and the mean value was 2.70.

• Journal of Environmental Impact Assessment
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• v.19 no.3
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• pp.323-333
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• 2010

$PM_{10}$ mass were measured in Gwaebeopdong (inland) and Dongsamdong (seashore) of Busan in summer and fall, 2007 and the 24-hour averaged samples were analyzed to investigate temporal and spatial variability of metallic elements and water-soluble ions in $PM_{10}$. Overall average concentrations of $PM_{10}$ mass during the study period were 72.7 ${\mu}g/M^3$ and 64.3 ${\mu}g/M^3$ in Gwaebeopdong and Dongsamdong, respectively. As for metal elements, averaged concentrations of crustal components, Ca, Fe, K, Mn, and Ti, in Gwaebeopdong exhibited enhancement relative to Dongsamdong. Non-crustal elements, Pb and Cu, displayed elevated levels in Gwaebeopdong while Ni and Zn were observed to be high in Dongsamdong. Averaged nitrate concentration in Gwaebeopdong (6.36 ${\mu}g/M^3$) was greater than in Dongsamdong(5.68 ${\mu}g/M^3$) and both areas had higher level of nitrate in summer than in fall. Averaged sulfate concentrations in Dongsamdong (25.4%) exhibited elevated level relative to Gwaebeopdong (19.4%). Overall average contribution of water-soluble ions to $PM_{10}$ in Dongsamdong (47.5%) was higher than in Gwaebeopdong (37.8%). The average mass fractions of secondary ions in $PM_{10}$ were elevated in Dongsamdong (37.1%) as compared to Gwaebeopdong (31.4%). Equivalent ratio of [${SO_4}^{2-}/NO_3{^-}$] was seen to be lower in Gwaebeopdong (1.39) than that in Dongsamdong (1.79) and consistently higher in summer than in fall for both areas.

• Journal of Nutrition and Health
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• v.33 no.7
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• pp.717-724
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• 2000

A number of epidemiological studies has indicated lifestyles including dietary habits are closely related to the development of certain forms of cancer. These findings have led several investigators to identify the ways in which these factors mdulate the risk of cancer. Seaweeds are rich sources of non-digestible polysaccharides which possibly posses physiological functions. In vitro studies showed several components in seaweeds inhibit tumor cell growth and mutagenicity of known food mutagens. On the other hand non-digestible polysaccharides of different food sources negatively affect mineral nutrition by decreasing mineral absorption. The objectives of this study was to investigate the effect of major seaweed intake on azoxymethane(AOM) - induced DNA damage a known cancer initiation step and on apparent absorption of calcium and iron. To accomplish these objectives twenty five ICR mice were divided into five groups and fed one of the following diets for 10 days : control diet d, diet containing 10% water-soluble fraction of seamustard or seatangle diet containing 10% water-insoluble fraction of seamustard or seatangle. AOM was injected 6 hours before sacrifice and N7-methylated guanines from the colonic DNA were quantified using a gas chromatography -mass spectroscopy. Fecal samples were collected on days 4 and 8. Caclium and iron contents of the diets and feces were analyzed using an atomic absorption spectrophotometry to determine the apparent absorption of these minerals. Results are as follows. AOM-induced guanine methylation of colon was decreased in animals fed diets containing water-soluble fractions of seamustard or seatangle compared to those in animals fed control diet although only the seatnagle fed group showed statistically significant effect. Apparent calcium absorption was significantly reduced in animals fed diets containing water-insoluble fractions of seaweeds. Iron absorption was significantly decreased and negatively balanced in animals fed diets containing water-insoluble fractions of both seaweeds, and water-soluble fraction of seatangle. In conclusion, seamustard and seatangle intakes may effectively prevent colon tumorigenesis by reducing a carcinogen-induced DNA damages, and more mechanistic studies on possible role of seaweeds on carcinogenesis are required. Also, adverse effects of seaweed diets cintaming a large amount of polysaccharides on mineral nutrition should be carefully monitored.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.521-524
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• 2008

The purpose of this study is to identify the character and condition of Cr in the clinker and thereby contribute to the research for reduction in utilizing Cr in the cement manufacturing process. The concentration of chromium by cement particle size and the distribution of chromium by clinker mineral were measured. Next, correlation was considered between chromium and the soluble components in cement. As a result, in the range that cement particles were 20${\mu}$m or less, highest soluble hexavalent chromium was found. When the concentration of chromium was measured through mineral separation, belite and the interstitial phase were higher in chromium than in alite. soluble hexavalent chromium was contained in domestic cement less than 20ppm, and its conversion ratio was somewhat high as 10 to 40% or so.

• Carbon letters
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• v.28
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• pp.38-46
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• 2018

Modified pitch A (MPA) and modified pitch B (MPB) were prepared by oxidative polymerization and thermal polycondensation reaction with refined pitch as the raw material, respectively. The toluene soluble components (TS-1 and TS-2) were obtained by solvent extraction from MPA and MPB, separately. The Flynn-Wall-Ozawa method and Kissinger-Akahira-Sunose method were used to calculate the pyrolysis activation energy of TS. The Satava-Sestak method was used to investigate the pyrolysis kinetic parameters of TS. Moreover, the optical microstructure of the thermal conversion products (TS-1-P and TS-2-P) by calcination shows that TS-1-P has more contents of mosaic structure and lower contents of fine fiber structure than TS-2-P. The research result obtained by a combination of X-ray diffraction and the curve-fitting method revealed that the ratios of ordered carbon crystallite (Ig) in TS-1-P and TS-2-P were 0.3793 and 0.4417, respectively. The distributions of carbon crystallite on TS-1-P and TS-2-P were calculated by Raman spectrum and curve-fitting analysis. They show that the thermal conversion product of TS-2 has a better graphite crystallite structure than TS-1.