• 분석과학
• /
• 제28권1호
• /
• pp.58-64
• /
• 2015

이 연구에서는 농촌지역 마을상수 중에 함유된 trihalomethanes (THMs)의 농도 분포 및 발생 특성을 파악하였다. 농촌지역의 마을상수 시료는 2010년과 2011년 여름에 강원도 춘천시의 40가정에서 두 차례에 걸쳐 채취하였고, 도시상수 시료는 2011년의 같은 기간에 비교 목적으로 20곳의 수도꼭지에서 채취하였다. 현장에서 수온, pH 및 잔류염소(총 및 유리) 농도를 측정하였고, 물 시료는 실험실에서 용존 유기탄소(DOC)와 THMs 농도에 대해 분석하였다. 마을상수 중 DOC의 평균 농도는 원수로 사용된 지하수와 지표수 간에 거의 차이를 보이지 않았다(1.81 vs. 1.91 mg/L). 그러나 마을상수의 지하수에서($9.77{\mu}g/L$)의 총 THMs(TTHMs)의 평균 농도는 지표수보다($2.85{\mu}g/L$) 훨씬 더 높았고, 도시상수 중 TTHMs의 평균 농도($10.8{\mu}g/L$)와 유사하였다. 도시상수와는 다르게, 마을상수(특히 지하수)는 dibromochloromethane (DBCM)과 같은 더 많이 브롬화된 THMs을 함유하였는데, 이는 마을상수의 원수 중에 bromide ion(Br-)이 비교적 높은 수준으로 존재함을 암시하였다. 이 연구를 통해 마을상수는 도시상수와는 다른 THMs 생성 특성을 나타내는 것을 알 수 있었는데, 이것은 아마도 원수의 수질 특성의 차이에서 비롯되는 것으로 생각된다.

• 동의생리병리학회지
• /
• 제16권1호
• /
• pp.141-145
• /
• 2002

In order to clarify the neuroprotective effect of Gamibojungikki-tang (GBJIKT) water extract on cultured mouse spinal sensory neuron damaged by glucose Oxidase (GO), MTT [3-(4,5-dimethylthiazole-2-yl) -2,5-diphenyltetrazolium bromide] assay and SRB (Sulforhodamine B) assay were carried out after the cultured mouse spinal sensory neuron were preincubated with various concentrations of GBJIKT water extract for 3 hours prior to exposure of GO. Cell viability of cultured mouse spinal sensory neurons exposed to various concentrations of GO for 8 hours was decreased in a dose-dependent manner. MTT50 values were 45 mU/ml GO. Cultured mouse spinal sensory neurons in the medium containing various concentration of GO for 8 hours showed decreasing of total protein synthesis. GO was toxic on cultured spinal sensory neurons. Pretreatment at GBJIKT water extract for 3 hours following GO prevented the GO-induced neurotoxicity such as decreasing of total protein synthesis. These results suggest that GO shows toxic effect on cultured spinal sensory neurons and GBJIKT water extract is highly effective in proecting the neurotoxicity induced by GO.

• Bulletin of the Korean Chemical Society
• /
• 제31권7호
• /
• pp.1907-1914
• /
• 2010

A novel catalytic kinetic method is proposed for the determination of Se(IV), Se(VI) and total inorganic selenium in water based on the catalytic effect of Se(IV) on the reduction of bromate by p-nitrophenylhydrazine at pH 3.0. The generated bromine, $Br_2$ or $Cl_2$ plus $Br_2$ in 0.1 M NaCl (or NaBr) environment efficiently decolorized Calmagite and the reaction was monitored spectrophotometrically at 523 nm as a function of time. In this indicator reaction, bromide acted as an activator for the catalysis of selenium (IV) and a reducing agent for selenium (VI) at pH 3.0, which allowed the determination of total selenium. The fixed time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the calibration graph are linear in the range 1 - 35 ${\mu}gL^{-1}$ of Se(IV) for the fixed time method at $25^{\circ}C$. The detection limit based on statistical $3S_{blank}$/m-criterion was 0.215 ${\mu}gL^{-1}$ for the fixed time method (7 min). All of the variables that affect the sensitivity at 523 nm were investigated, and the optimum conditions were established. The interference effect of various cations and anions on the Se (IV) determination was also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange resin such as Amberlite IR120 plus. The proposed kinetic method was validated statistically and through recovery studies in natural water samples. The RSDs for ten replicate measurements of 5, 15 and 25 ${\mu}gL^{-1}$ of Se(IV) and Se(VI) was changed between 2.1 - 4.85%. Analyses of a certified standard reference material (NIST SRM 1643e) for selenium using the fixed-time method showed that the proposed kinetic method has good accuracy. Se(IV), Se(VI) and total inorganic selenium in environmental water samples have been successfully determined by this method after selective reduction of Se(VI) to Se(IV).

• 한국약용작물학회지
• /
• 제24권1호
• /
• pp.31-37
• /
• 2016

Background : We studied the anti-oxidant activity and anti-inflammatory effects of Spiraea fritschiana Schneid extract (SFSE). Methods and Results : The SFSE was prepared using methanol and was evaluated for its total phenol and flavonoid content, DPPH (1,1-diphenyl-2-picrylhydrazyl) free-radical scavenging activity, reducing power, and effect on nitric oxide (NO) production, and cell viability by using real-time polymerase chain reaction (PCR). The total phenol content was $212.78{\mu}g{\cdot}galli$c acid equivalent (GAE)/mg and the total flavonoid content was $66.84{\mu}g{\cdot}quercetin$ equivalent (QE)/mg. The extract showed antioxidant activity (DPPH free-radical scavenging activity) with $RC_{50}$ value of $76.61{\mu}g/m{\ell}$. The reducing power of the extract was Abs 0.58 at $250{\mu}g/m{\ell}$. Cell viability was determined using the MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. To evaluate anti-inflammatory activity, we examined the inhibitory effects on lipopolysaccharide-(LPS)-induced NO production in RAW 264.7 cells. The NO inhibition rate was 90% at $200{\mu}g/m{\ell}$ SFSE. At the same concentration, the expression of pro-inflammatory genes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 also decreased. Conclusions : Our results suggest that SFSE is a novel resource for the development of foods and drugs that possess anti-oxidant and anti-inflammatory activity.

• Bulletin of the Korean Chemical Society
• /
• 제31권12호
• /
• pp.3567-3572
• /
• 2010

Black pine barks from the southern region of Korea were extracted using pressurized hot water and the water soluble extracts were then separated in a stepwise fashion using a variety of solvents, column chromatography (CC), thin layer chromatography (TLC), and high pressure liquid chromatography (HPLC). The antioxidant activities of each fraction and the active compounds were determined based on the radical scavenging activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), reductive potential of ferric ion, and total phenol contents. A DPPH test showed that the half maximal effective concentration ($EC_{50}$ value : $6.59{\pm}0.31\;{\mu}g/mL$) of the ethyl acetate fraction (ca. 0.67%) was almost the same as that of the control compounds and inversely proportional to the value of the total phenol contents. The cell viability of the water extracts was confirmed by methyl thiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) with enzyme linked immune sorbent assay (ELISA). Catechin, epicatechin, quercetin and ferulic acid were isolated from the ethyl acetate fraction as active compounds and identified by nuclear magnetic resonance. The antioxidant activity as value of DPPH of each of the separated compounds was lower than the ethyl acetate fraction, and ferulic acid was the lowest among these compounds.

• 한국물환경학회지
• /
• 제20권2호
• /
• pp.145-150
• /
• 2004

This study investigated the effect of chlorine dose and chlorine reaction time for the formation of haloacetic acids (HAAs). According to the results, HAA formation was highly affected by chlorine dose and chlorine reaction time. HAA formation reached a plateau value at 30 mg/L of chlorine dose and 24 hr of chlorine reaction time. For the speciation of formed HAAs in the test water, the concentration of brominated-HAAs was significantly lower than that of chlorinated-HAAs because of low level of bromide ion concentration in the test water. It also investigated the removal efficiency of HAA precursors by several unit processes, such as ozone alone, UV alone, and combined ozone/UV system. Of them, ozone/UV system was proved as the best process to control the HAAs formation. The increase of the brominated-HAAs was observed during ozonation with and without UV irradiation showing the slight increase of total HAA concentrations.

• International Journal of Concrete Structures and Materials
• /
• 제7권3호
• /
• pp.203-214
• /
• 2013

This study investigates quantitative methods for assessment of infrared analysis of concrete admixtures using correlation coefficients by performing IR scans following the ASTM C494/C494M-11 specifications. In order to achieve this goal, numerous IR scans were performed on specimens supplied by the manufacturer from different batches to ensure uniformity and equivalency. These scans were then analyzed to create correlation coefficients for each admixture. The correlation coefficients were used to quantitatively evaluate and interpret IR Scans of job samples. The study focused on 23 most commonly used concrete admixtures by the New Jersey Department of Transportation (NJDOT). They include air-entrainers, accelerators, retarders, water reducers, and other combinations of these admixtures. Their correlation coefficients were established by analyzing a total of 12 scans of each admixture from three different batches supplied by the manufacturer at different time intervals. In order to validate the obtained correlation coefficients and establish a target correlation, job samples were tested and compared to the obtained correlations. The study also evaluated the effects of drying time and using different types of KBr on correlation coefficients.

• 한국환경과학회지
• /
• 제18권12호
• /
• pp.1325-1330
• /
• 2009

The fumigant 1,3-dichloropropene (1,3-D) was recently proposed as a direct replacement for methyl bromide ($CH_3Br$) in soil fumigation. This study was conducted to better understand behavior phase partitioning, diffusion and volatilization of 1,3-D as affected by isomer. The Henry's law constant(KH) of cis-1,3-D and trans-1,3-D was 0.058 and 0.037 at $20^{\circ}C$, respectively. $K_H$ of cis form of 1,3-D was higher than that of trans form of 1,3-D. To compare with volatilization of 1,3-D isomer, soil column [70 cm (length)${\times}$12 cm (i.d.)] included a shank injection at 30 cm with 300 kg $ha^{-1}$. Maximum cis-1,3-D and trans-1,3-D concentration reached 57 mg $L^{-1}$ and 39 mg $L^{-1}$ at 30 cm depth at 1h after application. Cumulatively, after 10 days, 51.8% and 43.57% of applied cis-1,3-D and trans-1,3-D was emitted via volatilization, respectively. The total losses of cis-1,3-D were significantly greater than that of trans-1,3-D. Finally, cis-1,3-D and trans-1,3-D, such as isomer are dominant of 1,3-D fates in soil.

• 동아시아식생활학회지
• /
• 제5권1호
• /
• pp.21-27
• /
• 1995

The protective effect of omija methanol extract on benzo(a)pyrene induce liver injury was studied in rats in vitro and in vivo. In vitro experiment, primary cultured hepatocytes(5${\times}$105cells/$m\ell$) were cultured for 20∼24 hours after adding omija methanol extract(5.1$\mu\textrm{g}$/$m\ell$) and B(a)P(50$\mu\textrm{m}$) in culture medium. In vivo experiment, omija methanol extract(0.1g/kg/day, per os) was administered for 7days and B(a)P(0.1mg/kg body weight, intraperitoneally) was given to the rats after the last administration of extract. Omija methanol extract significantly recovered serum enzyme activities(AST, ALT and LDH) and lipid contents(total cholesterol, triglyceride and HDL-cholesterol) changed by benzo(a)pyrene (B(a)P) to normal levels in vivo. In vitro experiment, as a result of 3-(4, 5-dimethlythiazol-2-yl)-2, 5-diphenyl tetrazolium bromide(MTT) assay, omija methanol extract showed a little hepatotoxicity compared with group I (normal) but significantly recovered enzyme activities(AST, ALT and LDH) changed by B(a)P in comparison to group IIadministered B(a)P only. It was suggested that omija methanol extract has a protective effect on liver injury induced by B(a)P.

• 상하수도학회지
• /
• 제30권1호
• /
• pp.69-75
• /
• 2016

This study was conducted to examine the byproducts formation characteristics at the water treatment plants which applying electrolysis as a disinfection process in Gangwondo, Korea. Total of forty plants located in Gangwon Province, Korea were selected for the study. Correlation between dissolved organic carbon(DOC) and $SUVA_{254}$ was not clear. Among the species of the disinfection byproducts(DBPs), chlorate and trihalomethanes(THMs) accounted for 76% and 14% of DBPs, respectively. The effect of DOC or $SUVA_{254}$ on DBPs formation was not clearly demonstrated. The increased amount of THMs due to the raw water bromide content was found primarily in the form of chloroform, and the percent fraction of BDCM(bromodichloromethane) and DBCM(Dibromochloromethnae) was relatively insignificant. When the value of $SUVA_{254}$ was greater than $2L/mg{\cdot}m$, the percent fraction of BDCM and DBCM decreased while percent fraction of CF(chloroform) increased.