• YAKHAK HOEJI
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• v.24 no.2
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• pp.87-95
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• 1980

Chlorination to polluted water can produce chlorocompounds which may impair human health. It has been discussed that chlorophenols would be one of undesirable substances in drinking water. This study was undertaken to investigate the production mechanism of chlorophenols by chlorination in the disinfection of water and to determine pollution levels of phenols as precursor of chlorophenols and chloropbenols in some sewage, stream water and tap water in the vicinity of Seoul from January to September, 1979. By chlorination with hyperchlorite to phenols in distilled water, o-chlorophenol was predominantly produced at the concentration of less than 10ppm of free chlorine. o-Chlorophenol, 2,6-dichlorophenol and 2,4-dichlorophenol were also produced by chlorination with the concenration from 20 to 100ppm of free chlorine. From the concentration of 100ppm of free chlorine to 200ppm, o-Chlorophenol was vanished and 2,6-dichlorophenol and 2,4-dichlorophenol were determined. Phenols originated from night soil, municipal sewage and stream were determined at 49.15 ppm. 0.095 ppm and 0.003 ppm in average respectively. About 87 and 88 percent of phenols in sewage and night soil were biodegradated by aeration for 10 days and 74 and 51 percent of phenols in sewage and night soil by spontaneous settling for 10 days. From the tap water in Seoul during summer, 1979, chlorophenols were identified; they were average 0.042 ppb of o-chlorophenol, 0.033 ppb of 2, 6-dichlorophenol and 0.003 ppb of 2, 4-dichlorophenol respectively. With the above result and discussion, it is considered that chlorophenols should be controlled from the source as well as chlorination in water purification.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.214-219
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• 2007

66 micropollutants analyses in 9 wastewater treatment plants(WWTPs) along Nak-dong river were implemented to identify the concentrations and removal efficiencies before and after treatment processes. As a result of study, the concentration levels discharged from WWTP effluents to water system were below the water quality criteria and the levels of other studies. The removal efficiencies were 84.6%(DAF/CCR) and 81.6%(AC) for 1,4-dioxane. Phenol, Clphs and PAHs were removed 94.6%, 66.4% and 80.6% respectively by the activated sludge(AS) process. The removal efficiencies of Clbzs were 45.3% for the activated sludge(AS) process and 60.6% for the activated carbon(AC) process. However, other processes besides AS and AC, the removal efficiencies of Clbzs were very low(<20%). The sand filtration(SF) process that could remove particle matters showed the best efficiency for PCDDs / Fs removal$(\geq99%)$. However, in case of relatively low PCDDs/Fs concentration level in influent, the removal efficiency was not so high$(\leq50%)$.

• Journal of the Korean GEO-environmental Society
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• v.13 no.10
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• pp.69-76
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• 2012

This study focuses both on the quantitative measurement of hydroxyl radicals formed by an electron beam (E-beam) process and on the decomposition of pentachlorophenol(PCP) in the presence of $H_2O_2$ and $Fe^{3+}-EDTA$ as additives. To attain this objective, the quantitative measurement of hydroxyl radical was performed with the hydroylation of benzoic acid (BA), producing hydroxybenzoic acid (OHBA). As a result, the concentrations of hydroxyl radical measured were lower than those of hydroxyl radical predicted. Probably, it indicates that the reactive species generated during E-beam irradiation are able to scavenge the hydroxyl radicals. In particular, the degradation of PCP was promoted by the addition of $H_2O_2$ (< 1mM). On the other hand, its degradation as well as the generation of chloride ions as a by-product was inhibited by the addition of $H_2O_2$ (> 1mM), and thus carbon yield(%) of oxalic acid as a by-product was increased. During E-beam irradiation the addition of $Fe^{3+}-EDTA$ effectively decomposed the PCP, thus increasing the G-values. Considering the formation of OHBA and the decomposition of PCP, these results suggest that the addition of $Fe^{3+}-EDTA$ in the E-beam process can produce the further hydroxyl radicals and enhance the efficiency of PCP decomposition at low dose.

• Journal of the Korean Society of Food Culture
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• v.22 no.4
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• pp.454-461
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• 2007

Antioxidative and antimicrobial activities were carried out on the Citrus Unshju peel solvent extracts in order to discover new functional activities. The amounts of polyphenol in 70% metanol extract (MtEx) was measured as 836.8 mg% in Citrus Unshju peel. The EDA (electron donating ability) of 0.01, 0.02 and 0.1% MtEx in Citrus Unshju peel were measured as levels of 81.3, 86.0 and 89.6%. The nitrite scavenging effects of Citrus peel were also determined as the levels of 34.4% (pH 1.2) and 19.5% (pH 7.0). The pH of react solution was more acidic, the nitrite scavenging effect was more increased. The order of antioxidatives was shown as TBHQ > BHT > TOC > ChEx > EaEx > EtEx > WaEx > Control in corn germ oil and TBHQ > ChEx > EaEx > BHT > EtEx > WaEx > TOC > Control in canola oil. A number of the extracts were certified to have antimicrobial activities for a small number of micro-organisms, similar gram negative and positive micro-organisms. According to the results above, it was summerized that Citrus Unshju peel had the higher total polyphenol, EDA, nitrite scavenging effects and antimicrobial activities. Also isolated extract from ChEx and EaEx had high antioxidative, these effects were very similar to that of ${alpha}$-tocopherol and BHT. It would be proposed that Citrus peel can become a new natural source for antioxidative agents in future food industry.

• Journal of environmental and Sanitary engineering
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• v.22 no.2
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• pp.9-20
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and were mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasification/melting process is presented as an alternative of incineration process. The pyrolysis/gasification/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, t is investigated that the behavior of chlorobenzenes and chlorophenols in plasma type pyrolysis/gasification/melting plant of pilot scale. We investigated discharging behavior of each phase of chlorobenzene through each process in the plsasma type pyrolysis/gasification/melting process. From this result, it was found that about 99 percent of particle-phase chlorobenzene was removed, but on the other hand gas-phase chlorobenzene was increased by about 600 percent through heat exchanger, flue gas cooling, system and semi dry absorption bag filter(SDA/BF). Also, this investigation presented that di-chlorobenzene(DCB) tri-chlorobenzene(TCB), tetra-chlorobenzene(TeCB), penta-chlorobenzene (PCB), except mono-chlorobenzene(MCB) and hexa-chlorobenzene(HCB) were increased through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). It was investigated that concentration of particle-phase chlorophenol was decreased by about 66 percent, but on the other hand, concentration of gas-phase chlorophenol was increased by about 170 percent through heat exchanger, flue gas cooling system, and semi dry absorption bag filter(SDA/BF). Also, it was found that di-chlorophenol(DCP), tri-chlorophenol(TCP), and penta-chlorophenol(PCP) were increased through the flue gas cooling system, and the semi dry absorption bag filter(SDA/BF). It can be considered that small-scale pilot facility and short investigation period might cause the concentration increase through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). A further study on real-scale pilot facility and accurate investigation may be required.

• Journal of the Korean GEO-environmental Society
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• v.11 no.3
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• pp.5-16
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• 2010

Groundwater quality monitoring wells, which is over 2,000 in South Korea, were managed to observe groundwater quality since the early 1990s. Groundwater was sampled and analyzed biannually from 781 monitoring wells located in the areas with a high possibility of pollution. The average concentrations of cyanide, mercury, phenols, hexavalent chromium, trichloroethylene, tetrachloroethylen, and 1.1.1-trichloroethane for 12 years' data of detected cases were above the groundwater quality standard, but the average concentrations of the general quality items such as pH, electric conductivity, nitrate-nitrogen, and chloride, are below the standard. To compare a quality trend for each land-use type of the monitoring site, Sen's method is used for four quality items; chloride, nitrate-nitrogen, pH, and electric conductivity. The upward trend for these items is remarkable in urbideareas and industrial complexes and this trend continues still strongly after 2001. The deviation in a trend slopes of monitoring wells becomes bigger in the mid-2000s. In conclusion, trend analysis using existing monitoring data cidebe effective to forecast the future water quality condition and the solid action to protect groundwater quality should be done in advance using a result of trend analysis.

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.871-877
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• 1994

Most of the aromatic nitro compounds were reduced to amines in high yield by transfer of hydrogen from 4-vinyl cyclohexene to the substrate via palladium catalyst. The usefulness of the method is not affected by the presence of a variety of other functional groups such as -OH, $-OCH_3$, $-CH_3$, $-CO_2H$, and -Cl, except for halogen which is removed during hydrogenation. The reduction of ortho-substituted nitrobenzene such as o-nitrotoluene, o-nitrophenol, o-nitroanisole was slower than the para isomer. Typically, the nitro compound is refluxed in ethanol with a large exess of 4-vinylcyclohexene in the presence of Pd-C catalyst. Under the above conditions, p-nitrobenzaldehyde, p-nitrobenzyl alcohol, and p-nitrobenzyl acetate were reduced to p-toluidine.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.4
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• pp.517-524
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• 2011

Eleven polyphenolic compounds, including procatechuic and chlorogenic acids, (+)-dihydroquercetin, rutin, isoquercitrin, quercitrin, (+)-dihydrokaempferol, trans-resveratrol, moracin, quercetin and 4-prenylmoracin were isolated and purified from the methanolic extract of defatted mulberry seed residue by a series of column chromatography including silica gel, Sephadex LH-20, and ODS-A, and their chemical structures were identified by spectral analysis. The antioxidant activities of the eleven isolated polyphenolic compounds were measured spectrophotometrically using DPPH radical. Among the eleven polyphenolic compounds tested, rutin ($IC_{50}=20.2\;{\mu}M$), isoquercitrin ($IC_{50}=22.5\;{\mu}M$), quercitrin ($IC_{50}=24.6\;{\mu}M$), quercetin ($IC_{50}=27.8\;{\mu}M$), (+)-dihydroquercetin ($IC_{50}=28.9\;{\mu}M$), and chlorogenic acid ($IC_{50}=30.6\;{\mu}M$) exhibited stronger antioxidant activity than L-ascorbic acid ($IC_{50}=31.5\;{\mu}M$) and ${\alpha}$-tocopherol ($IC_{50}=52.3\;{\mu}M$), whereas procatechuic acid ($IC_{50}=68.2\;{\mu}M$) showed lower activity. In addition, (+)-dihydrokaempferol ($IC_{50}=33.8\;{\mu}M$), trans-resveratrol ($IC_{50}=36.2\;{\mu}M$), moracin ($IC_{50}=47.6\;{\mu}M$), and 4-prenylmoracin ($IC_{50}=48.2\;{\mu}M$) exhibited moderate antioxidant activity. Furthermore, levels of the eleven polyphenolic compounds from three different types of mulberry seeds were quantified by HPLC, and their contents were as follows: rutin (311~60.0 mg/100 g)> quercitrin (7.2~34.2 mg/100 g)> (+)-dihydroquercetin (13.2~33.1 mg/100 g)> quercetin (15.8~19.5 mg/100 g)> 4-prenylmoracin (10.5~43.3 mg/100 g)> isoquercitrin (5.8~15.4 mg/100 g)> chlorogenic acid (0.0~15.3 mg/100 g)> moracin (4.7~7.2 mg/100 g)> procatechuic acid (0.0~11.6 mg/100 g)> (+)-dihydrokaempferol and trans-resveratrol (<0.1 mg/100 g). The 'Daesungppong' mulberry seeds among the three cultivars had higher flavonoid contents, such as rutin and quercetin derivatives, while the 'Iksuppong' seeds had the highest contents of phenolic acids and moracin derivatives. 'Cheongilppong' had lower amounts of polyphenolic compounds than the other two mulberry seeds. These results indicate that mulberry seeds containing antioxidant polyphenolic compounds may be potentially useful sources of anti-diabetic, anti-hypertensive, and anti-aging agents for functional foods and cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.287-297
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• 2019

This study was carried out to evaluate the antioxidant, anti-inflammation, and whitening effect of Hordeum vulgare L. extracts and their fractions. Total polyphenol and flavonoid contents in fractions were varied from 13.58 to 40.06 mg GAE/g and 7.67 ~ 13.67 mg CE/g, respectively. Among the three fractions(chloroform, hexane, and water), $400{\mu}g/mL$ of the chroloform fraction showed similar antioxidant activity to ascorbic acid ($30{\mu}M$) against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The chloroform and hexane fractions inhibited the NO production of RAW 264.7 cells similar to quercetin ($15{\mu}M$) and the chloroform fraction of $100{\mu}g/mL$ significantly reduced IL-6, iNOS and COX2 gene expression. Additionally, the chloroform fraction inhibited ${\beta}$-hexosaminidase degranulation, IL-4, and IL-13 gene expression in RBL-2H3 cells. All of the fractions inhibited tyrosinase activity in a concentration-dependent manner, and the hexane fraction at $50{\mu}g/mL$ and the chloroform fraction at $100{\mu}g/mL$ significantly inhibited melanin production of B16F10 cells. These results indicated that H. vulgare L. can be used as an effective cosmetic ingredient having anti-inflammation and whitening activity.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.66-68
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• 2006

New synthetic method of 2-mercaptobenzoxazoles and 2-mercaptobenzimidazoles was established using elemental sulfur, dichloromethane, inorganic base and catalysts in alcohol solvents. This reaction condition gave products in high yields.