• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.109-113
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• 2006

Antioxidant compound(s) were identified from the ethanol extract of wild grape (Vitis coignetiea) seed. Organic solvent fractions of n-hexane, chloroform, ethyl acetate and butanol were obtained from the ethanol extract of wild grape seed, among which ethyl acetate fraction showed the strongest reducing power. Ethyl acetate fraction was further purified through ODS column chromatography and HPLC, and isolated antioxidative active compound was identified through $^1H-NMR$ as (+)-catechin (52.7 g/100 g). (+)-Catechin and ethyl acetate fraction both showed approximately 80% scavenging effect. These results indicated (+)-catechin in the ethyl acetate fraction synergetically interacts with unknown antioxidative compound(s).

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.287-290
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• 2015

Antifungal activities of pomegranate were investigated. Seventy percent ethanol extracts of seeds, peels, and whole fruits of pomegranate showed similar antifungal activities against Candida albicans in liquid media, whereas extract of whole fruit showed relatively high antifungal activity in solid media. When 70% ethanol extracts were fractionated sequentially with chloroform and ethyl acetate, ethyl acetate fraction exhibited the highest anti-fungal activities against C. albicans. Ethyl acetate fractions of whole fruits and peel portions showed at least 36% and 25% growth against C. albicans, Candida glabrata, Candida tropicalis, and Candida lusitaniae in liquid media, respectively. These results indicate that pomegranate contains antifungal compounds soluble with organic solvents.

• Polymer(Korea)
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• v.38 no.3
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• pp.307-313
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• 2014

The physical properties of functionalized graphene sheet (FGS)/poly(ethylene-co-vinyl acetate) (EVA) was examined with various kinds of EVA, having vinyl acetate (VA) contents in the range of 0 to 40 wt%. The compatibility between FGS and EVA was enhanced as the polar VA content of EVA increased. Thus, the dispersion of FGS in EVA became finer, and the decrease of surface resistivity and the increase of tensile modulus by the added FGS became more effective when the VA content of EVA was high. When the VA content was low, the elongation at break was reduced drastically by added FGS due to the poor adhesion of FGS/EVA interface. The crystallization of EVA was generally retarded by the interaction with dispersed FGS. However, when both the VA content of EVA and the added amount of FGS were low, the crystallization of EVA was enhanced, probably due to the predominant nucleating effect by FGS.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.46-48
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• 2003

Poly(vinyl alcohol) (PVA) obtained from PVPi has the highest syndiotacticity among (PVA)s obtained via radical polymerization, and the s-diad content of PVA prepared by low temperature polymerization of vinyl pivalate (VPi)[1-5] comes to eve. 60%, Therefore, we an obtain (PVA)s with various tacticities through the copolymerization of vinyl acetate (VAc) and VPi and can examine the relation between physical properties of (PVA)s and their tacticities. (omitted)

• Elastomers and Composites
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• v.54 no.2
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• pp.118-122
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• 2019

Four different polymer compounds were manufactured to make cable sheaths for the shipping industry. Two kinds of ethylene vinyl acetate (EVA) as the main matrix polymers and EVA-grafted maleic anhydride (EVA-g-MAH) as the coupling agent were selected for compounding with fire retardant, crosslinking agent, filler, plasticizer, and other additives. The properties of the four compounded materials were investigated with different contents of the fire retardant, silanecoated magnesium dihydroxide (S-MDH). In the rheology evaluation, the $t_{60}$ and ${\Delta}T$ values increased with increasing S-MDH contents. On the other hand, the tensile strength decreased with increasing S-MDH content due to a relative decrease in binder polymers. With increasing S-MDH content, fire resistance increased, but cold resistance showed no obvious enhancement due to the polar effect of vinyl acetate in EVA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1614-1618
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• 2014

To utilize Smilax china L. leaves as a natural preservatives, solvent fractions from crude methanol extract were prepared and investigated their antioxidant and antimicrobial activities against Staphylococcus aureus. Antioxidant activities were examined by 1,1-diphenyl-1-picrylhydrazyl radical scavenging and ferric ion reducing antioxidant power assays. Ethyl acetate fraction from Smilax china L. leaves exhibited the strongest antioxidant and antimicrobial activities among the fractions (P<0.05), as well as the highest total phenolic and total flavonoid contents. Caffeic acid, ferulic acid, quercetin, and kaempferol contents in the ethyl acetate fraction from Smilax china L. leaves were determined by TLC and HPLC. In aqueous phase, as well as the n-butanol and n-hexane fractions, quercetin, ferulic acid, and kaempferol were detected in small amounts. Ferulic acid, which showed the highest content, is the major active compound from Smilax china L. leaves.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.8
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• pp.1144-1149
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• 2015

The aim of this study was to investigate the antioxidant and antimicrobial activities of various solvent (acetone, ethyl acetate, and ethanol) extracts from Lentinus edodes. The antioxidant activities were evaluated by measuring total polyphenol and flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity. Total polyphenol content and ABTS radical scavenging activity were highest in ethanol extract. ABTS radical scavenging activity of ethanol extract showed the highest value (98.5%), which was similar to that of ascorbic acid (95.7%). The ethyl acetate extract from Lentinus edodes showed relatively high total flavonoid content and DPPH radical scavenging activity. Negative correlations were found between total polyphenol contents and DPPH radical scavenging activities in Lentinus edodes extracts. Antimicrobial activities of the extracts were determined against Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa, and Enterobacter cloacae by the disc diffusion method. The acetone and ethanol extracts showed moderate antimicrobial activities against almost all tested microorganisms except E. coli and S. aureus, respectively. The ethyl acetate extract showed a significant growth inhibition effect against E. coli, Ent. cloacae, and B. subtilis.

• Microbiology and Biotechnology Letters
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• v.35 no.1
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• pp.30-35
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• 2007

This study was carried out to investigate the usefulness of the aerial part of Cnidium officinale Makino as a bioactive material source. The aerial part(leaf and stem) of Cnidium officinale Makino was extracted with three kinds of solvents and determined their antimicrobial activities against several bacteria and yeast strains using the paper disc method and the microtiter dilution method. The extracts of the Cnidium offocinale aerial part exhibited the broad spectrum of antibacterial activity against Gram (+) and Gram (-) bacteria, including food-borne pathogens such as Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. The extracts of Cnidium officinale also showed antifungal activity against Saccharomyces cerevisiae. The ethyl acetate extracts completely inhibited the growth of Staphylococcus aureus and Pseudomonas aerogenes, and moderately inhibited the growth of Escherichia coli and Enterobacter cloacae at the concentration of 0.5 mg/mL. However, water extract of Cnidium officinale exhibited lower antimicrobial activity than ethyl acetate and methanol extracts. The inhibitory effect of the ethyl acetate extract of Cnidium officinale Makino was not destroyed by heating at $100^{\circ}C$ for 30 min or at $121^{\circ}C$... for 15 min. These results suggest that the aerial part of Cnidium officinale Makino could be a useful source for a natural antimicrobial material.

• Korean Journal of Veterinary Research
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• v.15 no.1
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• pp.23-25
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• 1975

Eight cattle and ten sheep were administrated various degree of PMA-B and EPN, and S-GOT, S-GPT and serum cholinesterase activity were tested. Serum cholinesterase activity showed no typical tendency, however, S-GOT/S-GPT ratios were decreased by the administration of PMA-B. It was suggested some degree of liver damage by the administration of the chemicals was recognized.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.298-300
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• 2001

Haematococcus pluvialis was cultured autotrophically and mixotrophically for astaxanthin production in bubble column photobioreactors with $CO_2$ and/or acetate supplements. Four different schemes were tested using 5% $CO_2$ balanced with 95% $N_2$ at the aeration rate of 0.1 vvm and supplementation of acetate (l g/L) to the basal medium, MBBM. Average specific growth rates based on cell total volume of each case were 0.138 $day^{-1}$ in control (without $CO_2$ and acetate supplements), 0.125 $day^{-1}$ with only acetate supplementation, 0.315 $day^{-1}$ with only $CO_2$ supplement, 0.304 $day^{-1}$with both $CO_2$ and acetate. The growth rate under $CO_2$ supply was much higher than that without $CO_2$ supply. DCO and DO seemed to be a possible limitation factor. Another interesting observation was the growth rate under $CO_2$ supplement (without acetate) was higher than that under both $CO_2$ and acetate supply. This result is the opposite of the previously reported works. From the result, the existence of acetate may suppress the dark reaction of $CO_2$ fixation or photosynthesis. Conclusively, the growth of H. pluvialis under photoautotrophic condition found to be higher than that under mixotrophic condition.