• Journal of the East Asian Society of Dietary Life
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• v.23 no.3
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• pp.374-381
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• 2013

The purpose of this study was to analyze the antioxidant effects and antimicrobial activity of extracts from yacon powder. The total polyphenol contents of yacon powder extracted with methanol was 38.5 mg/g, while extracted with water was 24.0 mg/g. Extractions with methanol were therefore more effective than with water. The total flavonoid contents of yacon powder extracted with methanol was 9.2 mg/g, while that with water was 7.8 mg/g. The electron donating ability of yacon powder extracts, natural antioxidant, and artificial antioxidant at 1.0 mg/mL arranged in order of decreasing concentration were ascorbic acid (98.7%) > BHT (44.7%) > methanol extract (12.1%) > water extract (7.8%). Nitrite-scavenging ability of yacon powder extracted with methanol at pH 1.2 was 13.1%, while that of powder extracted with water at pH 1.2 was 6.8%. And, the hydroxyl radical scavenging activities of yacon powder with methanol at 5 mg/mL was 40.2%. The antimicrobial activity of yacon powder extracted with methanol could be detected on Bacillus cereus ($10,000{\mu}g/disc$) and Staphylococcus aureus ($10,000{\mu}g/disc$).

• Fire Science and Engineering
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• v.29 no.2
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• pp.39-43
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• 2015

The flash point is the major property to characterize fire and explosion hazard of liquid mixtures. The flash point is the lowest temperature at which a liquid gives off enough vapor to form a flammable air-vapor mixture. The flash points of two aqueous mixtures, water-methanol and water-ethanol, were measured using Seta flash closed cup tester. A prediction method based on activity coefficient models, Wilson and UNIQUAC equations, was used to calculate the flash point. The calculated flash points were compared to the results by the calculating method using Raoult's law. The calculated values based on activity coefficients models were found to be better than those based on the Raoult's law.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.51-58
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• 2017

Antioxidant activities of 80% methanol, water, and 70% ethanol extracts of Lentinula edodes GNA01 were compared and estimated. The yield of Lentinula edodes GNA01 was identified to be in the following order: water>70% ethanol>80% methanol, but there was no significant difference between 80% methanol and 70% ethanol extracts. The highest total phenolic content (TPC) and total flavonoid content (TFC) were found in water extract, and TPC of 80% methanol extract was higher than that of 70% ethanol extract and TFC of 70% ethanol extract was higher than that of 80% methanol extract. Water extract exhibited the strongest DPPH, ABTS radicals, and nitrite scavenging activities, $Fe^{2+}$ chelating ability, and FRAP among the three extracts. In addition, antioxidant activity of 80% methanol extract was higher than that of 70% ethanol extract in most of the experiments. As a result, antioxidant activity of Lentinula edodes GNA01 showed a difference according to extraction solvent and concentration; nevertheless, water extract exhibiting high polarity had the strongest antioxidant effect. Consequently, water extract from Lentinula edodes GNA01 is anticipated to be useful for the development of a high value-added functional product.

• Korean Journal of Medicinal Crop Science
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• v.20 no.1
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• pp.16-19
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• 2012

The desmutagenic activity of the water extract of Areca catechu L. on the mutagenicity induced by aflatoxin $B_1$ ($AFB_1$), N-methyl-N-nitro-N'-nitrosoguani-dine (MNNG), mitomycin C (MMC) and 4-nitroquinoline 1-oxide (4-NQO) was studied by using the SOS Chromotest with Escherichia coli PQ37. The inhibition rates of water extract of Areca catechu L. at concentration of $100{\mu}g/assay$ were 41.0%, 47%, 46%, and 32% against $AFB_1$, MNNG, MMC and 4-NQO, respectively. The water extract of Areca catechu L. was separated into methanol soluble and methanol insoluble parts. The methanol insoluble part exhibited higher inhibition effect than the methanol soluble part against the mutagenic activities of MNNG. Step-wise fractionation of methanol insoluble part was done to obtain methanol, ethyl acetate and water fractions. Among these fractions, water fraction had the strongest inhibitory effect of 45.0% against mutagenicities of MNNG. The inhibition rates of aqueous fraction of methanol-insoluble from water extracted Areca catechu L. at concentrations of 1.61, 16.13, 161.29 and $322.58{\mu}g/mL$ were 12.0%, 24.0%, 47.5% and 62.0%, respectively. The water fraction showed the inhibitory effects with dose response against the mutagenic activity induced by MNNG.

• 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.

• Food Science and Preservation
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• v.7 no.1
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• pp.113-116
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• 2000

The antimicrobial activities of three parts of Korean sword bean , such as whole seed, dotyledon and hull were investigated . Yields were higher hull other parts in water and methanol extract. Methanol extract in seed parts was fractionated with different solvents, such as hexane, chloroform, ethyl acetate, butanol and water, yields of water fractino showed 3.3% , 2.5% and 0.3% in whole seed, 채쇼ledon and hull, respectively. In solvent extracts using methanol, hexane, chloroform, and water , methanol extract showed the most effective antimicrobial activities. Antimicrobial activities of ethyl acetate fraction of methanol extractwas higher than those of other fractions.

• Korean journal of food and cookery science
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• v.20 no.1
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• pp.81-85
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• 2004

This study was conducted to investigate the antioxidant activities of clove extracts in water, methanol and ether. The clove extracts, BHA and ${\alpha}$-tocopherol were added to each oil at a level of 200 ppm. The activities of the substrate oils and controls were tested under autoxidation and thermal oxidation conditions. The degree of the effects of the antioxidant activities under autoxidation condition were in the following order; ether extract 〉 methanol extract 〉BHA 〉 ${\alpha}$-tocopherol 〉 water extract = control group. The induction periods of the control, water, methanol and ether extracts, and BHA and ${\alpha}$-tocopherol were 9.5, 9.6, 10.7 11.8, 10.4 and 9.7 days, respectively. Under thermal oxidation condition, the methanol extract showed stronger antioxidant activity than those of the water and ether extracts. The antioxidant activity of the methanol extract was attributed to ${\alpha}$-tocopherol and BHA.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.51.4-51.4
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• 2019

We started a systematic observational study of the 22 GHz water and 44 GHz class I methanol masers in 87 high-mass young stellar objects (HM-YSOs) as a KaVA large program (LP). The primary goal is to understand dynamical evolution of HM-YSOs and their circumstellar structures by measuring spatial distributions and 3-dimensional velocity fields of multiple maser species. In the first-year observations (2016-2017), we made snap-shot imaging surveys of 25 water and 19 methanol maser sources. In the second-year observations (2018-2019), we have carried out monitoring observations of 19 water and 3 methanol maser sources that were selected on the basis of the first-year survey results. By combining follow-up observations with VERA (distances), JVN/EAVN (6.7 GHz methanol masers), and ALMA cycles 3 and 6 (thermal lines/continuum), we will provide novel information on physical properties (density, temperature, size, mass), 3D dynamical structures of disk/jet/outflow/infalling envelope, and relationship between evolutionary of HM-YSOs. In this presentation, we will report the current status and future plans of our KaVA large program.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.622-627
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• 2011

This study was designed to investigate the possible role of 10 green manure crop extracts in antimicrobial activity against potato common scab (Streptomyces scabiei). Ten green manure crops were extracted with hexane, ether, ethylacetate, methanol and water. The DPPH radical scavenging activity of ether, methanol and water was higher than those of hexane and ethylacetate fractions. The fractions of methanol, ethylacetate, ether and water showed antimicrobial activity against Streptomyces scabiei from the concentration of 0.25 mg/mL. Methanol fraction of Sorghum showed the highest antimicrobial activity against this microorganism. This result suggests the sorghum extract was the best as good green manure crop with antimicrobial activity against Streptomyces scabiei.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.3
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• pp.392-400
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• 2012

The purpose of this study was to analyze the physiological activity and antibiosis of mulberry powder by extract method. The total phenol content of mulberry powder extracted with methanol was 82.9 mg/g, while that of powder extracted with water was 46.9 mg/g. Extractions with methanol were therefore more effective than with water. The total flavonoid contents of mulberry powder extracted with methanol was 13.0 mg/g, while that of powder extracted with water was 9.4 mg/g. Also, the nitrite-scavenging ability of mulberry powder was lower than ascorbic acid and BHT. The SOD-like activity of mulberry powder extracts, natural antioxidant, and artificial antioxidant at 5 mg/mL arranged in order of decreasing concentration were ascorbic acid (98.3%) > BHT (88.1%) > water extract (9.8%) > methanol extract (3.0%). And, the OH radical scavenging activities of mulberry powder extracts and natural antioxidant at 5 mg/mL in order of decreasing concentration was ascorbic acid (97.0%) > methanol extract (46.2%) > water extract (35.8%). The antimicrobial effects of mulberry powder extracted with methanol could be detected on Bacillus cereus ($10,000{\mu}g/disc$) and Staphylococcus aureus ($10,000{\mu}g/disc$).