• Mycobiology
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• v.36 no.4
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• pp.249-254
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• 2008

Minimal growth inhibitory concentrations (MICs) of chitosan acetate (M.W. 60 kDa) on heterotrophic bacteria (strains MK1, S, and R) isolated from the soft-rotten tissues of Neungee mushroom (Sarcodon aspratus) were measured. The slimy substance produced by the MK1 strain was responsible for the diseased mushroom’s appearance. The S and R strains were members of the Burkholderia cepacia complex. These strains showed different levels of susceptibility toward chitosan acetate. The MIC of chitosan acetate against the MK1 and S strains was 0.06%. The MIC against the R strain was greater than 0.10%. Survival fractions of the MK1 and S strains at the MIC were $3\;{\times}\;10^{-4}$ and $1.4\;{\times}\;10^{-3}$ after 24 h, and $2\;{\times}\;10^{-4}$ and $7\;{\times}\;10^{-4}$ after 48 h, respectively. Survival fractions of the R strain after 24 and 48 hr at 0.1% chitosan acetate were $1\;{\times}\;10^{-2}$ and $6.9\;{\times}\;10^{-3}$, respectively. Compared to the MK1 and S strains, the low susceptibility of the R stain towards chitosan acetate could be due to the ability of the R strain to utilize chitosan as a carbon source. Thirty-eight percent of Neungee pieces treated in a 0.06% chitosan acetate solution for $2{\sim}3$ second did not show any bacterial growth at 4 days, whereas bacterial growth around untreated mushroom pieces occurred within 2 days. These data suggest that chitosan acetate is highly effective in controlling growth of indigenous microorganisms on Neungee. The scanning electron micrographs of the MK1 strain treated with chitosan revealed a higher degree of disintegrated and distorted cellular structures.

• Korean journal of applied entomology
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• v.5_6
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• pp.65-69
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• 1968

The effect of respiratory inhibition was investigated by treating conidia or mycelium of Cochliobolus miyabeanus with phenylmercuric 8-oxyquinolinate (PMQ) or. phenylmercuric acetate (PMA) in terms of $O_2$ up take ul/mg dry weight of cells. The results obtained are as follows: 1. In inhibition of mycelial growth, PMQ gave somewhat less effective than PMA, hut there was no remarkable difference between them, and the two indicated strong inhibitory effect on mycelial growth at the range from 0.01 to 1.0 ppm. 2. In inhibition of conidial respiration, PMA gave somewhat stronger than PMQ except at 0.1ppm, but there was no notable difference between them, and it seemed that there was no inhibitory effect at 0.01ppm. 3. PMQ was stronger than PMA in inhibition of mycelial respiration as compared with the cibudail respiration, ration, and the difference between them was about $10\%$. 4. According to the above results, the inhibitory effect of spore germimation by PMQ was the same as to PMA or somewhat lower than that of PMA. The inhibitiry effect of PMQ on mycelial growth was lower than that of PMA.

• Culinary science and hospitality research
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• v.17 no.1
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• pp.208-217
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• 2011

This study explores the antioxidant activity of solvent extracts from Vitis coignetiea skins, and the result is as follows. Total phenolic compound and flavonoids contents were the highest in ethyl acetate extract, $53.4{\pm}1.2\;mg$/100 g and $644.7{\pm}3.7\;mg$/100 g, respectively. Electron donating abilities of solvent extracts from Vitis coignetiea skin were proportionally increased with concentration and ethyl acetate extract ($80.93{\pm}0.58%$) showed the higher activity than BHT($63.21{\pm}0.72%$) at concentration of $50\;{\mu}l$/mL. Reducing power of solvent extracts from Vitis coignetiea skin was the highest in ethyl acetate extract(1.769) at concentration of $1,000\;{\mu}l$/mL. TBARS of ethyl acetate extract was higher than ascorbic acid. Nitrite scavenging ability of solvent extracts from Vitis coignetiea skin(pH 1.2, $1,000\;{\mu}l$/mL) was the highest in ethyl acetate extract($92.5{\pm}2.4%$).

• Journal of Radiation Industry
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• v.4 no.1
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• pp.73-77
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• 2010

In recent day, there is much interest in the biocidal activity of silver since silver is known to be safe and effective as disinifectant and biocidal material against coliforms and viruses. In this study, hydrogels containing silver acetate as antibacterial agent have been prepared using gamma rays irradiation. The hydrogels are composed of poly(vinyl pyrrolidone) (PVP), poly(ethylene glycol) (PEG), carrageenan and silver acetate. The concentration of solution was 9 wt%. The ratio of PVP : PEG : carrageenan was 6 : 1 : 2. The concentration of the silver acetate were 0, 0.01, 0.03, 0.05 and 0.07% and Gamma irradiation dose was 25 kGy. The Gamma irradiation dose in hydrogels with 0.01% silver acetate were 20 kGy, 35 kGy, 50 kGy, 65 kGy, and 80 kGy. The results showed that 0.01% silver acetate concentration of hydrogels by 25 kGy irradiation dose showed the highest antibacterial activity against E. coli and Staphylococcus aureus. Moreover, antibacterial activity of various Gamma irradiation dose in hydrogels treated 0.01% silver acetate showed highest 35 kGy irradiation dose against Staphylococcus aureus.

• Food Science and Preservation
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• v.6 no.1
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• pp.104-109
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• 1999

Ethyl acetate, methanol, water extract and their fractions from chestnut flower(Castancea crenata) were tested for antimicrobial activities. Yields of prebloomed chestnut flower extracts were 13.84, 12.90 and 1.82% in methanol, water and ethyl acetate, and those of the postbloomed were 13.12, 11.75 and 1.18%, respectively. Methanol extract from the chestnut flower was fractionated by solvents using hexane, chloroform, ethyl acetate, n-butanol and water, yields of those fractions were 0.16, 0.08, 1.94, 4.75 and 6.91% in the prebloomed, and were 0.90, 0.13, 1.40, 3.42 and 7.18% in the postbloomed. In the solvent extracts of water, ethyl acetate and methanol, methanol extract showed the most effective antimicrobial activity, antimicrobial activity of ethyl acetate fraction of methanol extract was stronger than others. Minimum inhibitory concentration of ethyl acetate fractions from the prebloomed showed 100, 140, 100 and 90ppm against Staphylococcus aureus, Streptococcus mutans, Echerichia coli and Salmonella typhimurium, in fractions from the postbloomed were 140, 140, 100 and 150ppm, respectively. Growth of all the strains was completely inhibited to 30 hours in a 150ppm concentration. E. coli sells treated with ethyl acetate fraction was collapsed severely.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.1
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• pp.42-47
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• 1987

The present studies were undertaken to prepare calcium acetate from sea-mussel shell and then, to investigate the calcium absorption ratio for calcium acetate by using young albino rate male. Purities such as chloride, nitrate, nitrate, sulfate, phosphate and heavy metal passed to test as reagent grade and calcium acetate assay was 99.0%. No significant differences in the body weight gain between calcium acetate group, calcium gluconate group and calcium carbonate group were not recognized. Diet consumptions of calcium acetate group was almost similar with calcium gluconate group and calcium carbonate group. It was found that absorption rate of calcium acetate was $57.68{\pm}0.83%,\;58.08{\pm}0.94%$ and was $2.0{\sim}3.0%$ high than calcium gluconate and calcium carbonate group.

• The Journal of Korean Medicine
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• v.22 no.1
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• pp.22-32
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• 2001

This study was conducted to investigate the antitoxic effects of Houttuynia cordata THUNB with chloroform and ethyl acetate fractions. The results were as follows: 1. Detoxication effects of chloroform and ethyl acetate fractions of Houttuynia cordata THUNB were increased in proportion to the dosages. Detoxication effects of ethyl acetate fraction of Houttuynia cordata THUNB were higher than chloroform fraction of Houttuynia cordata THUNB's results and detoxication effects in the kidneys were higher than results for the liver. 2. Metallothionein concentrations in the liver were higher than concentrations in the kidneys, and ethyl acetate fraction of Houttuynia cordata THUNB was higher than chloroform fraction of Houttuynia cordata THUNB in induction of metallothionein. 3. After the administration of chloroform and ethyl acetate fractions of Houttuynia cordata THUNB, body weights increased in proportion to chloroform and ethyl acetate fraction s dosage of Houttuynia cordata THUNB but changes of body weight dminished after 3 weeks. From the above results, this study suggests that chloroform and ethyl acetate fraction of Houttuynia cordata THUNB increased metallothionein induction to cadmium intoxication in rat s kidney and liver and decreased the toxicity of cadmium in rats.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1936-1943
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• 2015

The present study developed an efficient and environmentally friendly method for recovering polyhydroxybutyrate (PHB) from Cupriavidus necator. Several non-halogenated solvents were tested and it was found that butyl acetate and ethyl acetate are powerful solvents for the biopolymer. Testing was performed to examine the effects of temperature (25℃ until temperature below solvent boiling points) and heating incubation time (0-60 min) on the two solvents. Butyl acetate had a higher recovery level (96%) and product purity (up to 99%) than ethyl acetate at 103℃ and a heating incubation time of 30 min. Under these conditions, PHB recorded the highest molecular weight of 1.4 × 10⁶ compared with the standard procedure (i.e., recovery using chloroform). The proposed strategy showed that butyl acetate is a good alternative to halogenated solvents such as chloroform for recovery of PHB.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.630-636
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• 2005

Groundwater contamination by nitrate exceeding water quality criteria (10 mg $NO_3{^-}-N/L$) occurs frequently. Fumarate, acetate, formate, lactate, propionate, ethanol, methane and hydrogen gas were evaluated for their nitrate removal efficiencies and removal rates for in situ bioremediation of nitrate contaminated groundwater. Denitrification rate for each substrate was in the order of: fumarate > hydrogen > formate/lactate > ethanol > propionate > methanol > acetate. Microcosm studies were performed with fumarate and acetate. When fumarate was used as a substrate, nitrate was removed 100 percent with rate of 0.66 mmol/day while conversion rate from nitrate to nitrogen gas or another by-product was 87 percent. 42 mg of fumarate was needed to remove 30 mg $NO_3{^-}-N/L$. When using acetate as carbon source, 31 percent of nitrate was removed during initial adjustment period. Among removed fraction, however, 83 percent of nitrate removed by cell growth. Overall nitrate removal rate was 0.37 mmol/day. Acetate showed longer lag time in consumption compared to that of nitrate, which implying that acetate would be better carbon source compared to fumarate as more amount was utilized for nitrate removal than cell growth.

• Korean Journal of Pharmacognosy
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• v.51 no.2
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• pp.115-121
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• 2020

Caenorhabditis elegans model system was used to investigate the antioxidant activity of methanol extract of Mallotus japonicus twigs. The ethyl acetate soluble fraction of the M. japonicus methanol extract showed the best DPPH radical scavenging activity. The ethyl acetate fraction was measured for the activity of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans along with reactive oxygen species (ROS) level. In addition, to confirm that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the ethyl acetate fraction, SOD-3 expression was measured using a transgenic strain. As a result, the ethyl acetate fraction increased SOD and catalase activity, and decreased ROS accumulation in a dose-dependent manner. In addition, the ethyl acetate fraction-treated CF1553 worm showed higher SOD-3::GFP intensity than the control worm.