• KSBB Journal
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• v.11 no.4
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• pp.389-397
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• 1996

The growth of recombinant E. coli and formation of the by-products were investigated. Ammonium phosphate is known to affect the cell growth as well as the enzyme formation. When initial ammonium phosphate concentration was 0.5g/L, cell mass was 4.1g/L. By adding tryptone to the medium, acetic acid formation increased while lactic acid formation decreased. In cultivating recombinant E. coli, lactic acid and acetic acid turned out to be important by-products which affected cell yield and growth rate. Initial ammonium phosphate and tryptone concentration were optimized in our research and can be applied for other culture of recombinant E. coli.

• Natural Product Sciences
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• v.4 no.4
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• pp.263-267
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• 1998

From the dried flower-buds of Syzygium aromaticum Merr. et Perry (Myrtaceae), seven compounds, i.e., eugenol (1), oleanolic acid (2), kaempferol 7-O-metylether (3), 3,3',4-tri-O-methylellagic acid (4), maslinic acid (5), ${\beta}-sitosterol-3-O-glucoside$ (6), and isorhamnetin 3-O-glucoside (7) were isolated. Compound 1 showed cyclooxygenase-2 (COX-2) inhibitory activity.

• Biomedical Science Letters
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• v.25 no.3
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• pp.288-292
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• 2019

In vitro antimicrobial activities of hot water extracts of Camellia sinensis (L.) O. Kuntze, for carbapenem-resistant Enterobacteriaceae (CRE) were compared to commonly used conventional antimicrobial agents. CRE was not only resistant to imipenem, meropenem or ertapenem, but also to various antimicrobial agents, such as amikacin (> $128{\mu}g/mL$). The hot water extracts of Camellia sinensis (L.) O. Kuntze had the lowest MIC ($0.06{\sim}0.5{\mu}L/mL$) of the carbapenem-resistant E. coli, K. pneumoniae, and Enterobacter spp. tested, and it was possible more potent than various conventional antimicrobial agents. Synergistic combinations of the extract with used commonly antimicrobial agents might even improve its antimicrobial chemotherapy property.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.218-224
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• 2000

The antimicrobial activities of chitosan oligosaccharide(chitohexaose) and two types of chitosans M.W.(10,000 and M.W. 100,000) were examined against Escherichia coli O157 : H7(ATCC 43894), Staphylococcus aureus(ATCC 144458) and Candida albicans(KFRI 432). Chitosan with molecular weight of 10,000 showed the strongest antimicrobial activities to E. coil O157 : H7 and S. aureus, whereas chitohexaose acted most strongly against C. albicans. The most effective concentration of chitosan was measured to be 0.1 mg/mL for E. coil O157 : H7 and S. aureus, and that of chitohexaose to be 1 mg/mL for C. albicans. Antimicrobial activities of chitosans and chitohexaose were maintained for 60 min after their treatment. They were found to induce leakage of intracellular proteins and nucleic acids from treated microorganisms. The efflux determined by assaying the ${\beta}-galactosidase$ leaked from the lactose-induced E. coli O157 : H7 cells was observed to reach the highest level within 60 min after treatment with the antimicrobial agents and chitosan with 10,000 molecular weight gave the highest ${\beta}-galactosidase$ activity. Therefore, it is supposed that the antimicrobial activity of chitosan with its unique polycationic nature might be caused by its binding to anionic component(s) of the cell envelope and thereby inhibiting the membrane metabolism and/or leaking intracellular materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1337-1342
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• 2008

This study was conducted to investigate effects of chemical sanitizers on inhibiting foodborne pathogens, such as Listeria monocytogenes (L. monocytogenes), Salmonella Typhimurium (S. Typhimurium), and E scherichia coli O157:H7 (E. coli O157:H7), on cabbages. Cabbages were inoculated with the culture cocktail of pathogens and treated with water, 100 ppm commercial chlorine, and 50, 100, and 200 ppm chlorine dioxide ($ClO_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Treatments with water did not significantly reduce levels of three pathogens whereas other treatments with chemical sanitizers significantly reduced levels of three pathogens. Treatment with 200 ppm $ClO_2$ for 10 min was the most effective at inhibiting pathogens and reduction levels were 1.90, 1.92, and 1.98 log CFU/g for L. monocytogens, S. Typhimurium, and E. coli O157:H7, respectively. Levels of reduction were increased with the increase of $ClO_2$ concentrations. When chemically injured cells were investigated, there were no significant differences on the levels of injured cells between before and after treatment with commercial chlorine and $ClO_2$. These results suggest that $ClO_2$ can be used as an alternative sanitizer for reducing pathogens on fresh produces.

• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.84-93
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• 2005

The antibacterial activities of methanol extract and systematic solvent fractions( -hexane, chloroform, ethyl acetate, and butanol) from Korean common type figs at different ripening stages were tested by the broth dilution method against 8 representative food-poisoning bacteria- : L. monocytogenes, S. aureus, S. enteritidis, E. coli O157:H7, E. coli, Y. enterocolitica, V. parahaemolyticus, and S. typhimurium. The methanol extracts of unripened I and II showed stronger activity than that of the ripened figs especially against L. monocytogenes, S. enteritidis, E. coli O157:H7, Y. parahaemolyticus and S. typhimurium in 10 mg/mL. The systematic solvent fractions showed stronger antibacterial activities than the methanol extract, even al the lower concentrations. The hexane fraction of ripened figs showed higher growth inhibition than those of unripened I and II against L. monocytogenes, E. coli O157:H7, Y. enterocolitica and V. parahaemolyticus. The chloroform fraction showed strong antibacterial activity in all ripening stages against E. coli O157:H7 and V. parahaemolyticus. The butanol fraction showed better inhibition activity in unripened I and II than in the ripened figs. The hexane and chloroform fractions showed inhibition activity of more than $75\%$ against E. coli O157:H7, V. parahaemolyticus in 0.5 mg/mL. Each fraction showed a little different antibacterial activity according to the ripening stages of the fruits and the tested strains. Especially, figs in the unripened II stage revealed superior activity relatively and the hexane and chloroform fractions revealed the strongest activity, followed by the butanol fraction, while the ethylacetate and water fractions hardly showed any activity.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.178-183
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• 2001

This study was conducted to determine the optimal extraction condition of temperatures and kinds of extraction solvent, and antimicrobial activity of ethanol extract of Quercus mongolica leaf and organic acid against foodborne microorganisms. The antimicrobial activity of ethanol extract at $60^{\circ}C$ for 6 hour against foodborne microorganisms was stronger than those at $30^{\circ}C\;and\;90^{\circ}C$. Also, the ethanol extract showed stronger antimicrobial activity than those of water and methanol extract. The minimal inhibitory concentrations of the ethanol extract of Quercus mongolica leaf against B. cereus and L. monocytogenes, was $62.5{\sim}125\;{\mu}g/mL$ but, the minimal inhibitory concentration was $250\;{\mu}g/mL$ against S. typhimurium and P. aeruginosa and over $500\;{\mu}g/mL$ against E. coli O157:H7, respectively. The minimal inhibitory concentrations of the lactic, citric, acetic acid and the ethanol extract of Quercus mongolica leaf against B. cereus and L. monocytogenes was 2500, 5000, 1250 and $125\;{\mu}g/mL$, respectively. The combined effect of each organic acid and the ethanol extract against B. cereus was not observed but, synergistic effect was observed against L. monocytogenes. In the meantime, when the ethanol extract was combined with each organic acid at sub-lethal concentration, the combination did not increase the inhibitory effect of the most active single compound alone against E. coli O157:H7, respectively.

• Cross-Cultural Studies
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• v.25
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• pp.679-694
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• 2011

La langue est un des ${\acute{e}}l{\acute{e}}ments$ $privil{\acute{e}}gi{\acute{e}}s$ de la $r{\hat{e}}verie$ chez Bachelard. La langue est une force fondamentale de l'imagination. D'une part, elle garde son propre valeur dans le processus de l'imagination, et d'autre part elle forme sa propre image. La $priorit{\acute{e}}$ de langue chez Bachelard a, en effet, quelque liaison avec la notion de Logos qui avait ${\acute{e}}t{\acute{e}}$ $trait{\acute{e}}$ depuis longtemps comme $v{\acute{e}}rit{\acute{e}}$ ${\acute{e}}ternelle$ dans la $m{\acute{e}}taphysique$ occidentale. Cependant, la notion de logos de Bachelard se $diff{\grave{e}}re$ de celle de $m{\acute{e}}taphysique$ occidentale. Tandis que la $m{\acute{e}}taphysique$ traditionnelle traite le logos comme un but ${\acute{e}}ternel$ de sa $m{\acute{e}}ditation$, Bachelard donne l'importance sur la $capacit{\acute{e}}$ linguistique et imaginaire du logos. Le $logosph{\grave{e}}re$ est un des exemples qui montre bien la $diff{\acute{e}}rence$ entre la notion de logos de Bachelard et celle de $m{\acute{e}}taphysique$ traditionnelle. Le $logosph{\grave{e}}re$ est un $n{\acute{e}}ologisme$ de Bachelard qui est fait pour $d{\acute{e}}signer$ $l^{\prime}atmosph{\grave{e}}re$ verbal de la $soci{\acute{e}}t{\acute{e}}$ contemporaine $gr{\hat{a}}ce$ ${\grave{a}}$ l'emission de radio. Bachelard comprend le $ph{\acute{e}}nom{\grave{e}}ne$ de radio en tant que $r{\acute{e}}alisation$ de $Psych{\acute{e}}$ dans la vie quotidienne. C'est $gr{\hat{a}}ce$ ${\grave{a}}$ la technologie moderne que nous pouvons avoir l'univers de langue plus facilement par rapport aux $si{\grave{e}}cles$ $pr{\acute{e}}c{\acute{e}}dents$. Selon Bachelard, la radio n'est pas un simple instrument de communication. C'est une porte pour entrer dans la $r{\hat{e}}verie$ universelle. La radio est une voix du monde qui exprime notre inconscient. Quand un $r{\hat{e}}veur$ $r{\hat{e}}ve$, son $r{\hat{e}}verie$ se $d{\acute{e}}veloppe$ en se discutant avec le monde. Alors, quand nous $r{\hat{e}}vons$, nous parlons au monde et nous ${\acute{e}}coutons$ du monde, de sorte que nous devenons les citoyens du $logosph{\grave{e}}re$. Dans son oeuvre Sur la Grammatologie, J. Derrida critique la $m{\acute{e}}taphysique$ occidentale en la intitulant logocentrisme. Derrida pense que la philosophie occidentale a comme le but final la $pr{\acute{e}}sence$ de logos. Cette $pr{\acute{e}}sence$ de logos ne peut ${\hat{e}}tre$ $r{\acute{e}}alis{\acute{e}}e$ que par la langue de la voix, non pas par la langue de $caract{\grave{e}}re$. $D^{\prime}o{\grave{u}}$ vient le logocentrisme ou le phonocentrisme de $m{\acute{e}}taphysique$ occidental. Mais Derrida pense que le logocentrisme n'est qu'un autre aspect de l'ethnocentrisme ${\acute{e}}troit$ de l'occident. La notion de $logosph{\grave{e}}re$ de Bachelard a quelques ressemblances avec logocentrisme par ses apparences. Cependant, elles ont une $diff{\acute{e}}rence$ fondamentale depuis leur $d{\acute{e}}part$. Tandis que logocentrisme $tra{\hat{i}}te$ la parole en tant que $mani{\grave{e}}re$ d'expression de raison qui est une puissance fondamentale de l'homme, Bachelard pense que la parole est un $r{\acute{e}}sultat$ d'une opposition et fusion de notre raisons et parole. Bachelard pense que la parole est une $r{\acute{e}}alisation$ de l'image qui est l'essence de notre $psych{\acute{e}}$. Pour lui, la parole, la quintessence de $logosph{\grave{e}}re$, est le champ de l'imagination $d^{\prime}o{\grave{u}}$ jaillissent les images. C'est pour cela que $logosph{\grave{e}}re$ se situe ${\grave{a}}$ l'antipode de logocentrisme. $Logosph{\grave{e}}re$ nous fournit un espace de $r{\hat{e}}verie$ de langue. Notre $soci{\acute{e}}t{\acute{e}}$ contemporaine $fourr{\acute{e}}e$ des images visuelles creuses est $d{\acute{e}}pouill{\acute{e}}e$ de plus en plus des espaces de $r{\hat{e}}veries$. C'est une des raisons que le $logosph{\grave{e}}re$ de Bachelard doit ${\hat{e}}tre$ $r{\acute{e}}activ{\acute{e}}$ aujourd'hui.

• Natural Product Sciences
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• v.3 no.2
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• pp.106-107
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• 1997

Indole-3-methylethanoate was isolated for the first time form natural source i.e. from the leaves of Camellia sinensis (L.) O. Kuntz and fully characterized by physical and chemical evidence, the biological activity of the compound was studied by wheat coleoptile bioassay which showed growth promoting activity.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.440-447
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• 1997

The antibacterial effect of low concentrations of oregano (Origanum vulgare L.) in culture broth against Escherichia coli O157:H7 and Staphylococcus aureus 196E was tested at 35,5 and -20$^{\circ}C$. Tryptic soy broth (TSB) containing 0∼2% (w/v) of oregano was inoculated with 10$\^$6/∼10$\^$7/ CFU/$m\ell$ of E. coli or S. aureus and incubated at each temperature. The growth of E. coli was not inhibited at 0.1∼1.0% oregano and the growth occured at 2% oregano but only after a prolonged lag period. The death rate of E. coli after stationary phase was increased with increasing concentration of oregano in culture broth. The growth of S. aureus was inhibited with increasing concentration of oregano at 35$^{\circ}C$. Growth of S. aureus occured at the presence of 0.3∼0.5% oregano after a long lag period while the viability at 1.0∼2.0% was decreased during storage at 35$^{\circ}C$. During refrigerated storage at 5$^{\circ}C$, inhibition of E. coli or S. aureus was increased with the progress of time and increasing spice concentration. At the presence of 0.5∼2.0% oregano, E. coli and S. aureus were dead after 20 and 16 days of refrigerated storage, respectively. During frozen storage at -20$^{\circ}C$, the antibacterial activity of oregano against E. coli was increased with increasing storage time and spice concentration while the antibacterial activity against S. aureus was effective during the early period of storage, and no changes in the population of S. aureus occurred at different concentrations of oregano during frozen storage. Viable counts of E. coli were 1/3∼l/7 and S. aureus were 1/18∼l/46 of the control at 0.1% oregano in culture broth during frozen storage.