• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.7
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• pp.1009-1013
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• 2012

We investigated the antibacterial effects of Opuntia ficus indica extracts on foodborne pathogens, Escherichia coli O157:H7 and Listeria monocytogenes, on the medium of sliced apples. Pathogens were inoculated on sliced apples and immersed for 10 min in Opuntia ficus indica extracts. Each sample was packaged and stored at $4^{\circ}C$ and $21^{\circ}C$ for 8 days. The populations of E. coli O157:H7 and L. monocytogenes significantly decreased with increasing extract concentration (p<0.05). In particular, L. monocytogenes was reduced to non-detectable levels after 2 days in 50 mg/mL treatment at $4^{\circ}C$ and $21^{\circ}C$ Opuntia ficus indica extracts therefore have antibacterial effects on the two foodborne pathogens. Sensory evaluation results indicated that treated apples had better sensory characteristics than did the control. Therefore, the results suggest that Opuntia ficus indica extracts could be useful as a natural food preservative to improve microbial safety.

• Journal of Korean Philosophical Society
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• v.129
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• pp.167-191
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• 2014

Pour Kierkegaard la condition de l'homme naturel est tragique. $D^{\prime}{\hat{e}}tre$ $s^{\prime}{\acute{e}}veiller$, ${\hat{e}}tre$ ignorant et $d{\acute{e}}nier$ sur son vrai ${\hat{e}}tre$, tous causent le $d{\acute{e}}sespoir$. En plus l'homme ne peut avoir une conviction sur son bonheur $jusqu^{\prime}{\grave{a}}$ la mort. Donc sa $th{\acute{e}}orie$ du bonheur ne se base pas sur le bonheur. Tous le monde vit dans une situation $o{\grave{u}}$ il y a une distance entre $l^{\prime}{\hat{e}}tre$ $pr{\acute{e}}sent$ et son vrai ${\hat{e}}tre$. La vie ${\grave{a}}$ la perspective ${\acute{e}}thique$ s'apparaît comme se diriger vers son vrai ${\hat{e}}tre$ et ceci signifie $d^{\prime}{\acute{e}}tablir$ son ${\hat{e}}tre$ $int{\acute{e}}rieur$ en s'echappant la vie $esth{\acute{e}}tique$ qui est la vie sensitive et directe, et aussi faire s'identifier son ${\hat{e}}tre$ $ext{\acute{e}}rieur$ ${\grave{a}}$ son ${\hat{e}}tre$ $int{\acute{e}}rieur$. Le $p{\acute{e}}ch{\acute{e}}$ signifie la $s{\acute{e}}paration$ de son vrai ${\hat{e}}tre$, cela est la source de tout mal. L'obtention parfait de $l^{\prime}{\hat{e}}tre-soi$ exisge ${\hat{e}}tre$ en $pr{\acute{e}}sence$ devant l'Asolu(Dieu) en tant qu'individu unique, et s'accorder avec l'Absolu. Mais du fiat $m{\hat{e}}me$ que ceci est impossible pour tous, tout le monde ne peut vivre qu'ayant un peu de $p{\acute{e}}ch{\acute{e}}$. Donc l'aspect de la vie ${\acute{e}}thique$ s'apparaît une vie dynamique qui $d{\acute{e}}passe$ $soi-m{\hat{e}}me$ sans cesse. En contradiction qu'avec l'analyse sur $l^{\prime}{\hat{e}}tre$ $pr{\acute{e}}sent$ qui est si tragique, la vertu de cette vie ${\acute{e}}thique$ est si optimiste. Elle est l'amour. Cet amour est $tr{\acute{e}}s$ excellent qui $d{\acute{e}}passe$ toute la vertu ${\acute{e}}thique$. En $v{\acute{e}}rit{\acute{e}}$ pour Kierkegaard, bien que le salut $lui-m{\hat{e}}me$ sera donner par la foi, le principe de cet amour est l'unique vertu qui ammene l'homme vers la foi et vers le salut. C'est pourquoi son ${\acute{e}}thique$ est essentiellement s'apparaît 'une ${\acute{e}}thique$ de l'amour', et la recherche sur cet amour, son principe et son aspect reste comme uneque $t{\hat{a}}che$ de $l^{\prime}{\acute{e}}thique$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.875-880
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• 2012

This study was conducted to investigate the level of contamination of pathogenic Escherichia (E.) coli in 50 types of red pepper powders collected domestically. Pathogenic E. coli was confirmed using real-time PCR to confirm the 4 types of EAEC, EPEC, EHEC and ETEC. One sample out of 50 was contaminated with pathogenic E. coli. The type of pathogenic E. coli detected in the sample was EAEC. This study was also conducted to determine the effect of alcohol treatment on the reduction of E. coli populations in red pepper powder. The amount of E. coli in the control was $1.2{\times}10^6$ cfu/mL. The amount of E. coli in 10 minutes immersion treatment with 10% alcohol was $1.1{\times}10^6$ cfu/mL. In samples treated with over 20% alcohol, E. coli was not detected. This showed that 10 minutes of immersion in over 20% alcohol might be effective to reduce E. coli. This study was also conducted to determine the effect of UV irradiation on E. coli reduction. The number of E. coli in the control group was $5.0{\times}10^5$ cfu/mL. However, the number of E. coli in 45 min of the UV irradiated sample decreased to $1.0{\times}10^3$ cfu/mL, by $10^2$ cfu/mL. In contrast, E. coli was not detected in an over 60 min UV irradiated sample in $10^{-2}dilution$. This study showed that over 20% alcohol treatment and UV irradiation for 60 min was effective to control E. coli in red pepper powder.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.63-67
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• 2012

Antibiotic resistance in animal isolates of enterococci is a public health concern, because of the risk of transmission of antibiotic-resistant strains or resistance genes to humans through the food chain. This study investigated phenotypic and genotypic resistances profile of tetracycline in 245 $Enterococcus$ isolates from bovine milk. A total of 245 enterococci were isolated from 950 milk samples. The predominant strain was $E.$ $faecalis$ (n = 199, 81.2%) and $E.$ $faecium$ (n = 25, 10.2%). $E.$ $avium$ (n = 7, 2.9%), $E.$ $durans$ (n = 6, 2.5%), $E.$ $gallinarum$ (n = 4, 1.6%), and $E.$ $raffinosus$ (n = 4, 1.6%) were also isolated. Of the 245 enterococcal isolates 76.3% (n = 187) displayed tetracycline resistance (${\geq}16{\mu}g/ml$). Of the 187 tetracycline-resistant isolates, 83.4% (n = 156), 16.1% (n = 30), and 26.7% (n = 50) possessed the genes $tet$(M), $tet$(L), $tet$(S) respectively. While 3.2% (n = 6) of the tetracycline-resistant isolates possessed all three genes $tet$(M) + $tet$(L) + $tet$(S), 8.6% (n = 16), 16.0% (n = 30), and 2.7% (n = 5) of them possessed two genes $tet$(M) + $tet$(L), $tet$(M) + $tet$(S), and $tet$(L) + $tet$(S) respectively. The tetracycline resistance pattern investigated in this study was attributable mainly to the presence of $tet$(M).

• Journal of Life Science
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• v.17 no.11
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• pp.1492-1496
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• 2007

In vitro IgE class switching could be induced through co-culture of CD40L-expressing KU812 cells and CD40-expressing B cells in the presence of IL-4 or IL-13. It has been generated several B cell lines, which produce rice allergen (RA)-specific IgM antibody by in witγo immunization (IVI) using peripheral blood lymphocyte (PBL). In this study, induction of RA-specific IgE antibody by KU812 cells was attempted. Before co-culture, we determined the CD40 expression in RA-specific B cell lines, RA9G11 and the CD40 ligand (CD40L) expression in activated KU812 cells by treatments with phorbol myristate acetate (PMA) and ionomycin for 6 hrs. Flow cytometric analysis shown that RA9G11 and activated KU812 cells expressed high level of CD40 and CD40L, respectively. RA9G11 cells were cultured with activated KU812 cells for 12 days in the presence of IL-4 for IgE class switching. Mature $C{\varepsilon}$ mRNA level and RA-specific IgE spot forming cells (SFC) were observed in all culture condition, and especially, high level of RA-specific IgE synthesis was determined the same ratio of RA9G11 and activated KU812 cells in the presence of 50U IL-4. Therefore, induction of RA-specific IgE synthesis by activated KU812 cells can be contributed in the application for allergic therapy and prevention.

• Bulletin of the Korean Chemical Society
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• v.18 no.9
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• pp.929-933
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• 1997

Morphological studies in the micro-end-to-end (m-E-E) and micro-side-by-side (m-S-S) aggregations were conducted by using of scanning electron microscope (SEM) for the samples precipitated by heating of the end-products of the transition of FormⅡ (left-handed helix, three peptides per turn, 31) Form Ⅰ (right-handed helix, 3.3 peptides per turn, 103) in poly(L-proline) (PLP) in acetic acid(water)-propanol (1:9 v/v) solvent. The observed morphology for the solide state shows a rope (or super helical) type and pebbles type aggregate for the (m-E-E) and (m-S-S) aggregate respectively. The viscosities were also measured during the heat-precipitation in order to elucidate the process of formation of the rope- and pebbles-type aggregates. The result for the (m-E-E) aggregations exhibit two steps, i.e., at first, the viscosity increases with time (step 1), thereafter it decrease until attain the last value (step 2). But the (m-S-S) aggregations show only one step in the decreases in viscosity. On the bases of all experimental results it is possible to propose a reasonable mechanism for the formation of the two types of aggregates of the (m-E-E) and (m-S-S).

• Environmental Analysis Health and Toxicology
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• v.22 no.3
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• pp.263-269
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• 2007

Chitosan is a depolymerized and partially deacetylated derivative of chitin. We investigated the cytotoxicity of chitosan in cancer cell lines, such as P388, L1210, HCT-15, SK-HepG-1 and mouse splenocytes as a normal cell by MTT assay. To clarify whether chitosan enhances cytotoxicity of anticancer drugs, we also examined the cytotoxicity of combined treatment with chitosan and anticancer drugs, such as cisplatin, mitomycin C, and 5-fluorouracil in cancer cell lines in vitro. Chitosan ($37.5\;{\mu}g/mL,\;75\;{\mu}g/mL,\;112.5\;{\mu}g/mL,\;and\;150\;{\mu}g/mL$) showed concentration-dependent cytotoxicity in the cancer cell lines. In addition, chitosan showed relatively lower cytotoxicity in normal cells than in the cancer cell lines. Particularly, this trend was significant at high doses of chitosan, i.e. $112.5\;{\mu}g/mL,\;and\;150\;{\mu}g/mL$. Thus, these results suggest that chitosan may selectively induce the growth inhibition in cancer cell lines, compared to normal cells. Furthermore. the co-treatment of chitosan and anticancer drugs exhibited an apparant synergistic cytotoxicity in murine lymphoma cell lines, i.e. P388 and L1210 at $37.5\;{\mu}g/mL$ of chitosan rather than at $75\;{\mu}g/mL$ of chitosan, but such phenomenon could not be observed in solid tumor cell lines, i.e. HCT-15 and SK-HepG-1. However, chitosan did'nt reduced the cytotoxicity against normal mouse splenocytes induced by anticancer drugs. Therefore, it is concluded that the combination of chitosan and anticancer drugs might be useful for the cancer chemotherapy.

• BMB Reports
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• v.41 no.5
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• pp.363-368
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• 2008

Two genes of temperate mycobacteriophage L5, namely, gp63 and gp64, were hypothesized to be toxic to M. smegmatis. An identical L5 gp64 ortholog (designated hlg1) was cloned from homoimmune mycobacteriophage L1 and characterized at length here. As expected, hlg1 affected the growth of M. smegmatis when overexpressed from a resident plasmid. HLG1 (the protein encoded by hlg1) in fact caused growth retardation of M. smegmatis and the region encompassing its 57-114 C-terminal amino acid residues was found indispensable for its growthretardation activity. Both nucleic acid and protein biosynthesis were severely impaired in M. smegmatis expressing HLG1. Interestingly, HLG1 also affected E. coli almost similarly. This putative delayed early lipoprotein did not participate in the lytic growth of L1.

• Korean Journal of Food Science and Technology
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• v.33 no.3
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• pp.345-352
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• 2001

The volatile compounds of traditional Kyungsando squid sikhe were identified by GC-MS. The amount of ${\alpha}-zingibirene$ among identified volatile compounds was 19.73 mg/kg. The major volatile compounds of sikhe were (Z)-Di-2-propenyl disulfide, ${\alpha}-curcumene$, methyl allyl disulfide, (E, E)-a-farnesene, pentanol, z-citral, 3-ethyl-1,2-dithi-5-ene-${\beta}-elemene$, ${\beta}-elemene$, acetic acid, and ${\beta}-phellandrene$. The volatile compounds of sikhe were compose of 49 including hydrocarbone groups, 15 aldehydes groups, 33 alcohol groups kinds, 11 ketone and ester groups. The fraction obtained from sikhe were tested for electron donating ability, angiotensin converting enzyme inhibitory activity and xanthine oxidase inhibitory activity. There were no electron donating abilities$(SC_{50})$ in hexane and water soluble fractions. On the other hand, the angiotensin converting enzyme abilities of ethylacetate and butanol soluble fractions were $310.64\;{\mu}g/mL$ and $1096.49\;{\mu}g/mL$, respectively. Angiotensin converting enzyme inhibitory activities$(IC_{50})$ of ethylacetate butanol soluble fractions were 1.623 mg/mL and 1.303 mg/mL, respectively. Xanthine oxidase inhibitory activities$(IC_{50})$ of ethylacetate fraction and butanol soluble fractions were 3.591 mg/mL and 2.083 mg/mL, respectively.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.53-58
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• 2011

Cysteine and histidine-capped water-dispersible ZnS:Mn nanocrystals (ZnS:Mn-Cys and ZnS:Mn-His) were synthesized and their effects on E. coli and human cells were investigated. Particle sizes of these nanocrystals were found from HR-TEM images to be 3.5 nm and 4.0 nm, respectively. Their solution photoluminescence spectra showed identical broad emission peaks at 580 nm. ZnS:Mn-His significantly suppressed the growth of E. coli at $100{\mu}g/mL$ and 1 mg/mL concentrations, something not observed with ZnS:Mn-Cys. Consistent with this, greater inhibition of cell proliferation and viability were observed in HEK293 and IMR90 cells in ZnS:Mn-His at $100{\mu}g/mL$ and 1 mg/mL concentrations.