• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1745-1752
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• 2010

This study was conducted to investigate the antimicrobial activity of 70% ethanol (EtOH) extract and the five fractions of the crude extract from Sasa borealis leaves against seven food poisoning bacteria, Staphylococcus aureus, Micrococus luteus, Listeria monocytogens, Bacillus subtilis, Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa. The yield of 70% EtOH extract was 11.4% and those of n-hexane, chloroform, ethyl acetate, n-butanol, and aqueous fractions were 3.0%, 1.1%, 0.6%, 1.3%, and 5.1%, respectively. The 70% EtOH extract and the four fractions except aqueous fraction demonstrated antimicrobial activity against all the seven food poisoning bacteria at a concentration of 0.5%, although it was less compared to benzoic acid. Minimal inhibitory concentration (MIC) of the 70% EtOH extract against all the food poisoning bacteria except S. aureus was $50{\mu}L$/disc. Moreover, chloroform fraction was $35{\mu}L$/disc against 3 food poisoning bacteria and $50{\mu}L$/disc against the other 4 food poisoning bacteria; ethyl acetate fraction was $50{\mu}L$/disc against all the food poisoning bacteria. In addition, n-butanol fraction was $50{\mu}L$/disc against all the food poisoning bacteria except S. aureus. Aqueous fraction, which did not show antimicrobial activity at 5%, was $200{\mu}L$/disc against only S. aureus and L. monocytogen. The 0.25%, and 0.5% of ethyl acetate fraction inhibited the growth of all the food poisoning bacteria 8 to 12 hours and 24 hours, respectively. These results indicate that the Sasa borealis leaves may be useful as a natural antimicrobial substance.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.251-256
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• 2011

We screened for antibacterial substances against methicillin-resistant Staphylococcus aureus (MRSA). Methanolic extract of Eisenia bicyclis exhibited anti-MRSA activity according to a disk diffusion assay. To identify the active compound(s), the methanolic extract was further fractionated using hexane, dichloromethane, ethyl acetate, and n-butanol. The ethyl acetate-soluble fraction showed both the greatest anti-MRSA activity and the highest polyphenol content. The minimum inhibitory concentrations of the ethyl acetate fraction ranged from 32 to 64 ${\mu}g$ per mL against methicillin-susceptible S. aureus and MRSA strains. High-performance liquid chromatography analysis revealed that both the methanolic extract and the ethyl acetate soluble fraction contained sizeable quantities of dieckol, which is a known anti-MRSA compound. Thus, these data strongly suggest that the anti-MRSA activity of E. bicyclis may be mediated by phlorotannins such as dieckol.

• Journal of the Korea Safety Management & Science
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• v.17 no.4
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• pp.397-401
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• 2015

In this study, analysed the characteristics of power drop and surface damage in solar cell through high temperature and humidity test in the 3 case of EVA(ethylene vinyl acetate) and 2 case ribbon thickness. The solar cells were tested during the 500hr in $85^{\circ}C$ temperature and 85% relative humidity conditions, that excerpted standard of PV Module(KS C IEC-61215). Through the EL(Electroluminescence) shots, specimen's surface have partialy damaged. Before and after high humidity and high temperature test, ribbon thickness $200{\mu}m$ EVA1 case power drop rate was 8.463%, EVA2 case was 6.667%, EVA3 case was 6.373%. In the ribbon thickness $250{\mu}m$ EVA1 case power drop rate was 6.521%, EVA2 case was 8.517%, EVA3 case was 6.019%. EVA3 case was the lowest power and FF(fill factor) drop rate at the 2 case of ribbon thickness, because EVA3 is laerger than EVA1 and EVA2 in thickness, elongation and tensile strength.

• Bulletin of the Korean Chemical Society
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• v.5 no.3
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• pp.121-126
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• 1984

The charge transfer complex formations between indole derivatives and methylviologen were investigated spectroscopically. In aqueous solutions near room temperature, the order of complex stability was tryptamine < tryptophan < indole < indole acetate, which is the reverse order of the magnitude of molar absorptivities. This was interpreted as involvement of contact charge transfer. The decrease of enthalpy of complex formation (-${\Delta}$H) was highest in tryptamine, and lowest in indole acetate. ${\Delta}$H and entropy of complex formation (${Delta}$S) varied nearly in a linear fashion with isokinetic temperature $242^{\circ}$K. These results were attributed to the hydration-dehydration properties of the side chains in indole derivatives. Except indole acetate, the complex formations were greatly enhanced by the addition of sodium dodecyl sulfate(SDS). However, the direct relationship between the enhanced complex formation and SDS micelle formation was not found. The enhanced charge transfer interaction inSDS solutions was attributed to the increased ${\Delta}$S by interaction between methylviologen and SDS in premicellar level. The order of complex stability in SDS solutions was indole acetate < tryptophan < trypamine < indole, which reflects the hydrophobicity of indole derivatives as well as electrostatic interaction between indole derivatives and methylviologen associated with SDS.

• Korean Journal of Pharmacognosy
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• v.4 no.4
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• pp.185-188
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• 1973

In Cnidium officinale $M_{AKINO}$ and Platycodon grandiflorum A. $D_E\;C_{ANDOLE}$, chlorogenic acid was identified by Rf values, color reactions on paper chromatograms and UV-absorption spectra of the eluate of phenolic spots. And isochlorogeni acid-like substance was also found in the former. $1-Phenylalanine-U-C^{14}$ and sodium $acetate-2-C^{14}$ werse fed to both plants and their incorporation ratio to chlorogenic acid and isochlorogenic acid-like substance was compared. Phenylalanine was better precursor for chlorogenic acid in both plants than acetate. But acetate showed higher incorporation ratio to isochlorogenic acid-like substance in Cnidium officinale than that of phenylalanine.

• Journal of the Semiconductor & Display Technology
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• v.18 no.1
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• pp.42-47
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• 2019

The four different polymer compounds were manufactured to make cable sheath for ship industry. Two kinds of ethylene-vinyl acetate (EVA) were selected as main matrix polymers for compounding with fire retardant, crosslinking agent, filler, plasticizer, and other additives. The properties of the four compounded materials were investigated with the contents of fire retardant, silane coated aluminum hydroxide (S-ATH). Rheology, Mooney viscosity, and tensile strength increased with S-ATH contents by reinforcing effect. With increasing fire retardant amount, fire resistance increased, but cold resistance didn't show an obvious enhancement due to polar effect of vinyl acetate in EVA.

• Membrane Journal
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• v.24 no.6
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• pp.484-490
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• 2014

To find out the feasibility of the separating/enriching esters from aqueous solution using FASs (Fluoloalkyl-silanes-coupling agent)-surface modified hydrophobic membrane, the solubility parameter of FASs was obtained and compared with those of esters and water. The value of the solubility parameter of FASs (${\delta}_t=16.9$) was almost same with those of esters (ethyl acetate ${\delta}_t=18.1$, propyl acetate ${\delta}_t=18.0$, ethyl propionate ${\delta}_t=17.9$, butyl acetate ${\delta}_t=17.4$, ethyl butyrate ${\delta}_t=17.0$). However, the calculated value of the solubility parameter of water was ${\delta}_t=47.8$, which was far from the value of the solubility parameter of FASs (${\delta}_t=16.9$). This means that the FASs-modified membrane has a much higher affinity to esters than water. The experimental results of permeation flux of esters used in this study showed that the order of permeation flux predicted by the solubility parameter was almost coincide with experimental results. It might be concluded that the solubility parameter may be applicable for a separating/enriching flavors from aqueous natural-flavor solution, in which esters are main components of natural flavors.

• Journal of Life Science
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• v.30 no.1
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• pp.40-44
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• 2020

This study investigated the anti-bacterial and anti-inflammatory activities of Artemisia iwayomogi Kitamura for medical and food additive applications. A 70% methanol extract of A. iwayomogi Kitam. was fractionated with a series of solvents in order of increasing polarity; these fractionated extracts showed high 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging activity in the ethyl acetate fractions and high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity in both the ethyl acetate and chloroform fractions. Levels of total phenolics and flavonoids were highest in the ethyl acetate fraction extracts. Eight bacteria were then treated with the A. iwayomogi Kitam. extract fractions and most showed similar or lower levels of anti-bacterial activity when compared to the control group, except for Staphylococcus aureus. In addition, the anti-oxidant activities of the ethyl acetate fractions of the A. iwayomogi Kitam. extract were higher than those of the other fractions. To confirm the anti-inflammatory activity of the extract fractions, we applied them to RAW 264.7 cells using LPS, and the results indicate that an ethyl acetate fraction at 250 ㎍/ml concentration inhibits nitric oxide production. This study demonstrates that an ethyl acetate fraction of A. iwayomogi Kitam. extract inhibits bacterial and inflammatory activities and could be useful as a potential source of bioactive compounds.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.40-46
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• 2005

This study was performed to investigate the antimicrobial effects of the Citrus unshiu Markovich extracts against food-borne pathogens. First, the Citrus unshiu Markovich was extracted with methanol at room temperature, and fractionation of the methanol extracts from Citrus unshiu Markovich was carried out by using petroleum ether, chloroform, ethyl acetate, and methanol. The antimicrobial activity of the Citrus unshiu Markovich extracts was determined using the paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of Citrus unshiu Markovich showed the highest antimicrobial activity against Bacillus cereus and Shigella sonnei. A synergistic effect was found in combined extracts of Citrus unshiu Markovich and Hedyotis diffusa Willd as compared to each extract alone. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Citrus unshiu Markovich against Bacillus cereus and Shigella sonnei. The ethyl acetate extract of Citrus unshiu Markovich showed strong antimicrobial activity against Bacillus cereus at the concentration of 5,000 ppm. The 5,000 ppm of ethyl acetate extract from Citrus unshiu Markovich retarded the growth of Bacillus cereus more than 24 hours and Shigella sonnei up to 24 hours. The ethyl acetate extracts of Citrus unshiu Markovich have shown an antimicrobial effect against Bacillus cereus and Shigella sonnei.

• Korean Journal of Animal Reproduction
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• v.25 no.2
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• pp.147-153
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• 2001

This study was performed to elucidate the effects of lead poisoning on the reproductive organ of rats. After consecutive oral administrations of lead acetate, the weights of testis, the numbers and motilities of sperms and histological changes of organs were compared between control and experimental groups. 1. Testis weights of 1,000, 2,000 or 4,000 ppm/kg of lead acetate-administrated rats decreased compared with control group in dose-dependent manner. 2. The sperm numbers of 1,000, 2,000 or 4,000 ppm/kg of lead acetate-administrated rats were lowered significantly in dose dependent manners than those of control groups. 3. The sperm motilities of 1,000, 2,000 or 4,000 ppm/kg of lead acetate-administrated rats decreased in dose-dependent manners compared with those of control groups. 4. The weights of livers and kidneys of 1,000, 2,000 or 4,000 ppm/kg of lead acetate-administrated rats decreased or increased. The weights of livers increased and the kidney weights decreased and changes were dose-independent manner. 5. Necrosis of hepatocytes around the central veins, infiltrations of neutrophils, accumulations of bile and infiltrations of fine granules-harboring macrophages in psychymal and interstitial tissues were found out in the livers of copper sulfate-administrated rats. The Bowman's capsule, tubular epithelium and includes in nucleus of kidneys were filled with hyaline materials and hematophilic centers appeared in several lymph nodes.