• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.360-363
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• 2000

The anaerobic bacterium P. productus was known to produce acetate from CO, $CO_2$ and $H_2$. In this research the production of acetate at high concentration from carbon monoxide was studied. In this research the effect of $CO_2$, $H_2$, and CODH co-factor on cell growth and acetate production was studied. Also the toxicity of acetate on cell growth was examined. Acetate formation in lab scale fermenter was tested and specific acetate production rate of $0.43\;g/L \;{\cdot}\;hr\;{\cdot}\;O.D.$ was obtained and the concentration of the acetate obtained in a fermenter higher than 40g/L.

• Journal of Plant Biology
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• v.16 no.1_2
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• pp.6-11
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• 1973

The utilization of acetate by Dunaliella tertiolecta was examined, and the detections and assays of the enzymes of the tricarboxylic acid cycle and the glyoxylate pathway were described. Acetate could not be utilized as a sole carbon source for the growth. The carboxyl carbon of acetate was incorporated more rapidly into CO2 than the methyl carbon. It was identified that malate, succinate, citrate and etc., were accumulated whne [U-14C] acetate was supplied to the cell free homogenate. The following enzyme activities were measured; acetothiokinase, isocitrate dehydrogenase, fumarase, malate dehydrogenase and aconitase. Though isocitratase, malate synthetase, succinate dehydrogenase and oxoglutarate dehydrogenase could not be detected, 14C from succinate was easily contributed to CO2 and cell component. The evidence suggested that the glyoxylate pathway was not operative and showed that the TCA cycle was the all important pathway in the oxidation of acetate to CO2 in Dunaliella.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.5
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• pp.437-444
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• 2007

Vinyl acetate has been widely used for the manufacture of polyvinyl alcohol emulsion, which is primary ingredient of adhesive, paints, textile, paperboard coatings, etc. Since these products are plentiful and frequently used around us, workers and consumers are at health risk. International Agency for Research on Cancer(IARC) classified vinyl acetate as group 2B(possibly carcinogenic to humans). Among the organs targeted, the oral cavity is the most vulnerable organ affected by the carcinogenic effects of vinyl acetate. Since the origin of most of oral cancer is derived from the epithelial cells, it is important to understand the carcinogenic potential of vinyl acetate in human epithelial cells. Thus, the present study has attempted to utilize the immortalized human epithelial cell model to assess the carcinogenic potency of this chemical and to understand the underlying mechanisms.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.849-852
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• 2001

The preparation, characterization and drug release behaviour of hydrocortisone(HC) loaded levan acetate microparticles were investigated. Hydrophobic levan acetate was prepared by chemical modification of hydrophilic levan and micro particles were made by dialysis method or solvent evaporation method. The morphology of levan acetate was observed by SEM and drug release profiles were investigated at pH 7.4 and pH 1.2. Newly synthesised levan acetate can be used for carrier of drugs.

• The Korean Journal of Zoology
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• v.15 no.3
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• pp.101-104
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• 1972

A simple and economical method for separation of lactate and malate dehydrogenase isozymes is described in detail. The method is based on cellulose acetate strip electrophoretic separation of the isozymes, tetrazolium reduction to purple formazan. Resolution is as good as in the experiment using expensive equipments.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.352-357
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• 2009

Due to rapid consumption of hydrogen peroxide, large amount of hydrogen peroxide is required when Fenton reaction is applied to the contaminated soil. In this study, acetate was employed as a ligand of $Fe^{2+}$ to enhance the efficiency of removal of phenanthrene by securing the stability of hydrogen peroxide. 0.5 ${\sim}$ 3 times of acetate (2${\sim}$12mM) was added to compare with molar concentration of $Fe^{2+}$. Low initial concentration of hydrogen peroxide was 0.7% to eliminate side effect of removal efficiency. The results showed that hydrogen peroxide lifetime was lasted up to 72 hours, or more than 50 times of normal lifetime. Phenanthrene removal efficiency was improved up to 70% due to stabilized hydrogen peroxide. Ferrous ion was oxidized to ferric ion and oxidation-reduction was repeated during the reaction. Finally ferric ion was reduced to ferrous by $HO_2$. It was confirmed that, due to the influence of hydrogen peroxide, pH was acid region and it remained at the range of 4 ${\sim}$ 5 when 8 mM or more of acetate was added. Acetate which was used as the ligand of Fe was also decomposed by Fenton reaction. The decomposition time of acetate was slower than phenanthrene. Therefore, it was able to come to the conclusion that phenanthrene was superior to acetate at the competition for decomposition. Through the results of this study, it was able to identify the possibilities to improve the efficiency of Fenton reaction in the contaminated soil and its economic feasibility, and to move to more realistic technique through research expanded to neutral pH region.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1331-1337
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• 2012

The study analyzed the total polyphenolic contents, DPPH radical scavenging activities, ABTS radical scavenging activities, reducing power levels, SOD-like activities, and tyrosinase inhibition activities of fractions from Campanula takesimana Nakai extract. Total polyphenolic content of the ethyl acetate fraction from Campanula takesimana Nakai extract was the highest. The ethyl acetate fraction of Campanula takesimana Nakai extract showed the lowest $IC_{50}$ value (0.13 mg/mL) as well as greater than 98% ABTS radical scavenging activity, which was similar to ascorbic acid. Further, reducing power was significantly higher in the ethyl acetate fraction. The SOD-like activity of edible plant was 70.56% (n-butanol fraction) and 62.27% (ethyl acetate fraction) at 1 mg/mL. Tyrosinase inhibition activity of Campanula takesimana Nakai extract was reduced to 34.77% in the n-butanol fraction and 30.85% in the ethyl acetate fraction at 5 mg/mL. These results suggest that the ethyl acetate and n-butanol fractions of Campanula takesimana Nakai extract could be applicable as food additives or cosmeceutical ingredients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1382-1388
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• 2008

Antimicrobial activities of green tea extracts used for coarse tea were investigated by disc diffusion method using eight different bacteria. Among the green tea extracts, the 70% ethanol extract demonstrated the strongest antimicrobial activities against Vibrio parahemolyticus (V. parahemolyticus) and Staphylococcus aureus (S. aureus) and thus was further fractionated. Among these fractions, the ethyl acetate fraction showed the strongest antimicrobial activities against V. parahemolyticus, S. aureus, Bacillus subtilis (B. subtilis), and Streptococcus mutans (S. mutans). These activities exceeded that of all extracts and fractions tested in this study. Interestingly, although green tea extracts showed significant antimicrobial activity against Micrococcus luteus (M. luteus), once fractionated, the ethyl acetate fraction did not show any antimicrobial activity against M. luteus. MICs of the ethyl acetate fraction were $5\;\;{\mu}L$/disc against B. subtilis and $3\;{\mu}L$/disc against S. aureus, S. mutans and V. parahaemolyticus. 90% inhibition of B. subtilis was observed with 0.05% ethyl acetate fraction but S. mutans needed over 0.1% ethyl acetate fraction to exhibit the same inhibition as B. subtilis. Antimicrobial activities of ethyl acetate fractions were reduced around 10% by thermal treatment at $121^{\circ}C$ for 20 min. All the results suggest that the 70% ethanol extract as well as the ethyl acetate fraction from green tea used for coarse tea could be further developed into a natural antimicrobial agent.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.139-145
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• 2001

This study was performed to elucidate the patho-physiology of lead acetate-poisoned rats after consecutive oral administrations of the lead. The changes in feed and water intake, gains of body weight, blood pictures and mineral compositions of several organs were observed to measure the effects of lead acetate-poisoning. 1. Compared with control group, every experimental group of which 1,000, 2,000, or 4,000 ppm/kg of lead acetate was administered displayed a gradual decrease in feed intake in dose-dependent manners. 2. After 1,000, 2,000 or 4,000 ppm/kg of lead acetate administration, water intake seemed to decrease in every experimental group in dose-dependent manners. 3. After 1,000, 2,000 or 4,000 ppm/kg of lead acetate administration, body weight decreased in every experimental group in dose-dependent manners. 4. After 1000, 2,000 or 4,000 ppm/kg of lead acetate administration, the PLT values and numbers of RBC and WBC significantly increased after lead acetate administration, but the values of Hb and PCV were lower than those of control group's. 5. After 2,000 or 4,000 ppm/kg of lead acetate administration, the levels of Pb, Mn, Fe, Pb and Zn in the livers were lowered, but the levels of Pb, Mn, Fe, Pb and Zn in the kidneys.

• Korean Journal of Pharmacognosy
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• v.48 no.1
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• pp.63-69
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• 2017

Saururus chinensis (Lour.) Baill. (Saururaceae) has been used as a traditional medicine for the treatment of dysuria, leukorrhea, eczema, jaundice and ascites in Korea, China and Japan. Ethanol extract of S. chinensis was successively partitioned as methylene chloride, ethyl acetate, n-butanol and $H_2O$ soluble fractions. Among those fractions the ethyl acetate soluble fraction showed the most potent DPPH radical scavenging and superoxide quenching activities. To verify antioxidant activities of ethyl acetate fraction, we checked the activities of superoxide dismutase (SOD) and catalase, and intracellular ROS level and oxidative stress tolerance in Caenorhabditis elegans. Furthermore, to see if increased stress tolerance of worms by treating of ethyl acetate fraction was due to regulation of stress-response gene, we quantified SOD-3 expression using transgenic strain. Consequently, ethyl acetate fraction elevated SOD and catalase activities of C. elegans, and reduced intracellular ROS accumulation in a dose-dependent manner. Moreover, ethyl acetate fraction-treated CF1553 worms exhibited significantly higher SOD-3::GFP intensity.