• Korean Chemical Engineering Research
• /
• v.47 no.1
• /
• pp.96-104
• /
• 2009

In order to lower a reaction temperature with high conversions for simultaneous catalytic reduction of NO and $N_2O$ over Pd-Rh supported mixed metal oxide honeycomb catalysts, $H_2$ or CO was utilized as a reductant. When using the reductants, the effects of reaction conditions were examined in NO and $N_2O$ conversions, where reaction temperatures, concentrations of the reductants and oxygen and the concentration ratio of $N_2O$ to NO were varied. In using $H_2$ reductant, larger than 50% of NO and $N_2O$ conversions was observed at the temperatures below $200^{\circ}C$ in absence of $O_2$. In using CO reductant, NO and $N_2O$ conversions increased from the temperatures higher than $200^{\circ}C$ and $300^{\circ}C$, respectively. However, in use of both reductants, NO and $N_2O$ conversions decreased with increasing oxygen concentration. As a result, $H_2$ reductant could reduce simultaneously NO and $N_2O$ at relatively lower reaction temperature than CO. Also, NO and $N_2O$ conversions were less influenced by using $H_2$ reductant than CO one. Concentration ratio between NO and $N_2O$ did not affect their conversions regardless the type of reductants. Pretreatment of the catalyst in $H_2$ was more effective in simultaneous reduction of NO and $N_2O$ at low reaction temperature than that in $O_2$.

• Journal of Sasang Constitutional Medicine
• /
• v.15 no.1
• /
• pp.90-108
• /
• 2003

Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) has been developed as prescriptions for the Soyeumin constitution. The hepatoprotective effect of the water extract of Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) was investigated against carbon tetrachloride (CCl4)-induced hepatic damage. A single intra-peritoneal injection of CCl4 produced liver damage in rats as manifested by the significant rise of aspartate aminotransferase(AST), alanine aminotransferase(ALT), and alkaline phosphatase(ALP) in serum as compared to those of untreated normal group. Pretreatments of rats with Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) 500 mg/kg for 7 days) were significantly reduced AST, ALT, and ALP levels compared with CCl4-treated control group. Treatment of rats with CCl4 led to significantly increase in lipid peroxidation and significantly decrease in cytochrome P450 and P450 reductase. The oral administration of Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) water extract significantly inhibited the accumulation of microsomal thiobarbituric acid reactive substance (TBARS) and increased the cytochrome P450 and P450 reductase activity. All these biochemical alterations resulting from CCl4 administration were inhibited by the pretreatment with Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SG1) extract. These results suggest that Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) water extract can be useful as a hepatoprotective agent. And the effect of NO modulation by NO synthesis or precursors, and Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang (SGT) water extract was researched on chronic liver damage induced by CCl4 administration. It was observed that endogenous NO protected the liver from lipid peroxidation, fibrosis, and damage. Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) water extract showed the hepatoprotective effect on the chronic liver cirrhosis model and relationship with NO modulation.

• Proceedings of the Ginseng society Conference
• /
• 1988.08a
• /
• pp.81-86
• /
• 1988

The effect of three polyacetylene compounds. panaxydol. panaxynol and panaxytriol isolated from Korean ginseng on $CCI_4-induced$ lipid peroxidation in vitro and in vivo hepatic microsomal lipid peroxidation were investigated. Lipid peroxide levels both in serum and liver and serum enzyme (GOT. GPT. LDH) activities of normal or $CCI_4-treated$ mice and rats were also determined after administration of polyacetylenes. Hepatic microsomal cytochrome P-450 content and activities of aniline hydroxylase and aminopyrine demethylase were measured after treatment of polyacetylenes with or without carbon tetrachloride. As results. treatment with polyacetylenes to control mice did not influence the levels of lipid peroxides and serum enzyme activities while panaxynol did. Panaxynol itself inhibited liver lipid peroxidation in normal mice. Polyacetylene compounds protected hepatic lipid peroxidation and lowered serum lipid peroxide levels induced by $CCI_4$ Polyacetylenes prevented leakage of LDH to serum but elevated GOT and GPT levels caused by $CCI_4$ were not changed by polyacetylene pretreatment. $CCI_4$ caused losses in the content of cytochrome P-450 and activities of aniline hydroxylase and aminopyrine demethylase. When polyacetylenes were treated without $CCI_4$ panaxydol and panaxynol induced aniline hydroxylase and all three polyacetylenes induced aminopyrine demethylase. Cytochrome P-450 contents were not affected by polyacetylenes. In vitro hepatic microsomal lipid peroxidation was inhibited by polyacetylenes and $DL-{\alpha}-tocopherol$ in a concentration-dependent manner.

• Applied Chemistry for Engineering
• /
• v.29 no.6
• /
• pp.690-695
• /
• 2018

Advanced oxidation processes (AOPs) composed of O3 and UV were applied to degrade penicillin (PEN). The degradation efficiency was evaluated in terms of changes in the absorbance (ABS) and total organic carbon (TOC). The combination of $O_3/H_2O_2/UV$ and $O_3/UV$ showed the best performance for the reduction of ABS (100% for 9 min) and TOC (70% for 60 min) values, although the mineralization was uncompleted under the experimental condition in this study. The change in biotoxicy was monitored with Escherichia coli susceptibility and Vibrio fischeri biofluorescence. The E. coli susceptibility was eliminated completely for 9 min by $O_3/UV$, and the toxicity to V. fischeri biofluorescence was 57% reduced by $O_3/H_2O_2/UV$. For the ultimate treatment of PEN, it is suggested that an AOP using $O_3/UV$ is followed by biological treatment, utilizing the enhanced biodegradability by the AOP. During 30 min of $O_3/UV$ treatment, the $BOD_5/COD$ ratio as an indication of biodegradability showed about 4-fold increment, compared to that of using a non-treated sample. TOC removal rate for AOP-pretreated PEN wastewater increased 55% compared to that of using the non-pretreated one through an aerobic biological treatment by Pseudomonas putida for artificial wastewater containing 20 mg/L of PEN. In conclusion, $O_3/UV$ process is recommended as a pretreatment step prior to an aerobic biological process to improve the ultimate degradation of penicillin.

• Resources Recycling
• /
• v.27 no.6
• /
• pp.68-75
• /
• 2018

The rare earth elements (REE) contents in coal ashes generated from domestic circulating fluidized bed combustion (CFBC) were identified for evaluating the exploitation possibilities for recovering rare earth elements. Total REE contents for all of the samples in this study ranged from 82.2 ~ 311.7 ppm, much lower than the 403.5 ppm given on the average value of world coal ash. As a result of analysis using REE concentration and Outlook coefficient, six types of coal ashes falls in the unpromising area (I). These results suggest that it is difficult to recover rare earth element from coal ashes at this stage. It has been confirmed that to recover rare earth elements in coal ashes, research on the pretreatment and concentration process for critical REE is requirement.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.28 no.1
• /
• pp.1-8
• /
• 2022

With the spread of COVID-19 worldwide, non-face-to-face services have grown rapidly, but at the same time, the problem of plastic waste is getting worse. Accordingly, eco-friendly policies such as carbon neutrality and sustainable circular economy are being promoted worldwide. Due to the high demand for eco-friendly products, the packaging industry is trying to develop eco-friendly packaging materials using PLA and PBAT and create new business models. On the other hand, Ulva australis occurs in large quantities in the southern seas of Korea and off the coast of Jeju Island, causing marine environmental problems. In this study, lactic acid was produced through dilute acid pretreatment, enzymatic saccharification, and fermentation processes to utilize Ulva australis as a new alternative energy raw material. In general, seaweeds vary in carbohydrate content and sugar composition depending on the species, harvest location, and time. Seaweed is mainly composed of polysaccharides such as cellulose, alginate, mannan, and xylan, but does not contain lignin. It is difficult to expect high extraction yield of the complex polysaccharide constituting Ulva australis with only one process. However, the fusion process of dilute acid and enzymatic saccharification presented in this study can extract most of the sugars contained in Ulva australis. Therefore, the fusion process is considered to be able to expect high lactic acid production yield when a commercial-scale production process is established.

• Clean Technology
• /
• v.29 no.4
• /
• pp.272-278
• /
• 2023

There is a lot of interest in methods for pollutants using adsorption, and recent research is being conducted to show that biochar can be used to remove organic and inorganic pollutants. In particular, wood waste as waste biomass requires a biomass recycling method, and a method to increase the adsorption capacity of biochar produced using wood waste is needed. Biochar is created by Hydrothermal carbonization (HTC) using, which uses low temperature and high pressure, has low energy consumption and does not require moisture removal pretreatment, and biochar is created through chemical activation using KOH, NaOH, and ZnCl₂ chemicals. The adsorption characteristics of biochar were determined by analyzing iodine adsorptivity, specific surface area, pore diameter, pore volume, pore distribution, and SEM according to the activation. The results of analyzing the selecting biochar by activating the biochar produced at HTC 300℃, 4 hr by KOH, NaOH, and ZnCl₂ chemicals, the specific surface area was 774~1.387 m²/g, showing a high specific surface area similar to activated carbon, and it was confirmed that micropores with an average pore diameter in the range of 21~24 Å were formed. As a result of SEM observation, the surface was uniform with a certain shape depending on activation. It was confirmed that one pore was developed and the number of pores increased.

• Journal of the East Asian Society of Dietary Life
• /
• v.21 no.5
• /
• pp.731-738
• /
• 2011

Cholesterol is the precursor of various steroid hormones, bile acid, and vitamin D with functions related to regulation of membrane permeability and fluidity. However, the presence of excess blood cholesterol may lead to arteriosclerosis and hypertension. Moreover, dietary cholesterol may affect blood cholesterol levels. Generally, cholesterol determination is performed by spectrophotometric or chromatographic methods, but these methods are very time consuming and costly, and require complicated pretreatment. Thus, the development of a rapid and simple analysis method for measuring cholesterol concentration in food is needed. Multi-walled carbon nanotube (MWCNT) was functionalized to MWCNT-$NH_2$ via MWCNT-COOH to have high sensitivity to $H_2O_2$. The fabricated MWCNT-$NH_2$ was attached to a glassy carbon electrode (GCE), after which Prussian blue (PB) was coated onto MWCNT-$NH_2$/GCE. MWCNT-$NH_2$/PB/GCE was used as a working electrode. An Ag/AgCl electrode and Pt wire were used as a reference electrode and counter electrode, respectively. The sensitivity of the modified working electrode was determined based on the amount of current according to the concentration of $H_2O_2$. The response increased with an increase of $H_2O_2$ concentration in the range of 0.5~500 ${\mu}M$ ($r^2$=0.96) with a detection limit of 0.1 ${\mu}M$. Cholesterol oxidase was immobilized to aminopropyl glass beads, CNBr-activated sepharose, Na-alginate, and toyopearl beads. The immobilized enzyme reactors with aminopropyl glass beads and CNBr-activated sepharose showed linearity in the range of 1~100 ${\mu}M$ cholesterol. Na-alginate and toyopearl beads showed linearity in the range of 5~50 and 1~50 ${\mu}M$ cholesterol, respectively. The detection limit of all immobilized enzyme reactors was 1 ${\mu}M$. These enzyme reactors showed high sensitivity; especially, the enzyme reactors with CNBr-activated sepharose and Na-alginate indicated high coupling efficiency and sensitivity. Therefore, both of the enzyme reactors are more suitable for a cholesterol biosensor system.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.9
• /
• pp.1344-1349
• /
• 2005

The aim of this study was to evaluate the effects of Welsh onion administration on $CCl_4$-induced hepatic injury in rats. The increasing rate of the body and organ weight was not significantly different by the ad-ministration of the Welsh onion. Welsh onion (2, 4, $10\%$ w/w) was given for 4 weeks with the injections of $CCl_4$. Total serum lipid was significantly decreased in all treatment groups compared to $CCl_4$ only treatment group (p<0.05). The Welsh onion from winter season was more protective effect by lowering the serum levels of transminase (SGOT and SGPT) compared with others, the levels of transminase - phosphatase (ALP) in serum. The Welsh onion from winter at a dose of $4\%,\;10\%$ (w/w) showed significantly hepatoprotective activity which was comparable to that $CCl_4$-induced hepatic damage. Histological evaluation showed that Welsh onion partially prevented $CCl_4$-induced inflammation, necrosis and vacuolation. Pretreatment of Welsh onion reduced extent of the necrosis found 24 hr after the intraperitoneal administration of $CCl_4$. The present study shows the liver protective action of the Welsh onion against experimentally induced liver damage in rats. This suggests that the Welsh onion may be used as an effective hepatoprotective agent.

• Korean Journal of Medicinal Crop Science
• /
• v.9 no.2
• /
• pp.116-123
• /
• 2001

This study was carried out to investigate antioxidative, antimicrobial activity and the effect on hepatotoxicity in various extracts of Artemisia iwayomogi. The herb has been used widely for jaundice, hepatitis and liver cirrhosis in chinese medicine. Solid yield by various extraction solvents, 18.1%, was the highest in water extract. To find antioxidative activity in Artemisia iwayomogi was estimated radical scavenging effect by DPPH method in various extracts and change of the POV(peroxide value) of various extracts added in soybean oil during 20 days at $60^{\circ}C$. Radical scavenging effect by DPPH method was the most effective in methanol extract. Added 1,000ppm water extract and methanol extract in soybean oil, the POV of them, 46.8(meq/kg) and 50.8(meq/kg) were lower than that of control, 79.1(meq/kg), during 20 days storage. After antimicrobial activity of various extracts of Artemisia iwayomogi on bacteria was carried out by paper disc method, it found that the ethanol extract was the strongest activity on Vibrio parahaemolyticus. In vivo experiment was to investigate the effect of Artemisia iwayomogi water extract(AIWE) on hepatotoxicity by carbon tetrachloride$(CCl_4)$ in rats. The experiment groups were divided into five groups for recovery(for 3 days) and three groups for protection(for 10 days) in rat liver. The weights and morphological changes of liver and the body weight were examined in each groups. Compared with $CCl_4$ treatment groups$(CCl_4\;only)$, liver and liver/body(%) weights of AIWE pretreatment groups for 3 days and AIWE posttreatment groups for 10 days were declined. In macrography, fibrious exudates and swelling of liver were decreased in AIWE treatment groups. Accumulation of lipid droplets and necrosis of hepatocytes were also decreased in AIWE treatment groups in microscopically. In these results, AIWE seems to enhance hepato-protective and recoverable effect on $CCl_4$ induced hepatotoxicity in rats.