• Food Science and Preservation
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• v.6 no.2
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• pp.239-244
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• 1999

Antimicrobial activity to the extracts of Perilla frutescens Briton var. acuta Kudo was investigated against various foodborne pathogenes or food poisioning microorganisms(Aspergillus flavus KCTC 6143 and KCTC 6961, Aspergillus niger ATCC 4695, Listeria monocytogenes ATCC 15313, Staphylococcus aureus 196E ATCC 13565, Escherichia coli O157:H7 ATCC 43895, Salmonella typhimurium ATCC 13311 and Yersinia enterocolitica). The ethanol extract of Perilla frutescens Briton var. acuta Kudo was very stable over heat at $121^{\circ}C$ for 15 min. In concentration of $1000\mu\textrm{g}$/mL into culture broth(TSB), the ethanol extract of Perilla frutescens Briton var. acuta Kudo showed the strongest antimicrobial activities against Listeria monocytogenes, followed by Staphylococcus aureus 196E, Salmonella typhimurium. Gram negative bacteria(Escherichia coli O157:H7, Salmonella 쇼phimurium, Yersinia enterocolitica) were less sensitive than Cram positive bacteria but the growth of Escherichia coli O157:H7 and Yersinia exterocolitica were inhibited with increasing concentrations of the extract in culture broth.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.612-617
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• 2012

The antioxidant, antimicrobial, and cytotoxic activities of ovotransferrin were investigated in vitro. The antioxidant capacity of ovotransferrin was evaluated using the 2,2-Diphenyl-1-picryl hydrazyl (DPPH) radical scavenging method, antimicrobial effects using the agar well diffusion method, and cytotoxicity using the 3-(4,5-dimethylthizol-2-yl)-2,5-diphenylatetetrazolium bromide (MTT) assay. The DPPH radical-scavenging capacity of ovotransferrin at 1 mg/mL level reached approximately 60% after 48 h of reaction. The antimicrobial effects of ovotransferrin against common food-borne pathogens, Staphylococcus aureus KCCM 32395, Bacillus cereus KCCM 40935, Listeria monocytogenes ATCC 15313, Escherichia coli O157:H7 ATCC 43895, and Helicobacter pylori HpKCTC 26695 were dose dependant. Gram-positive bacteria was more sensitive to ovotransferrin than gram-negative bacteria. Ovotransferrin showed stronger antimicrobial effect against L. monocytogenes than other gram-positive bacteria tested. The cytotoxicity of ovotransferrin was evaluated in human cancer cell lines, various tissue origins, including the larynx (Hep-2), stomach (AGS), lung (SK-MES-1), liver (HepG2), breast (MCF-7), cervix (HeLa), and colon (HT-29). Ovotransferrin displayed relatively high cytotoxicity (${\leq}60%$ inhibition effects) at 40 mg/mL. At lower concentrations (${\leq}10mg/mL$), however, ovotransferrin cytotoxic effects were not significant in all cancer cell lines tested. These results indicated that ovotransferrin has potential to be used as an antioxidant or antimicrobial agent in foods or a pharmaceutical agent against cancers.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.651-655
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• 1985

A series of S-(2,2-diethoxycarbonyl-1-phenylethyl)-L-glutathione derivatives (11a-e) were synthesized from the reaction of ${\beta},\;{\beta}$-diethoxycarbonylstyrene with L-glutathione in 9 : 1 aqueous methanol. Thus, S-(2,2-diethoxycarbonyl-1-phenylethyl)-L-glutathione (11a), S-2,2-diethoxycarbonyl-1-(3',4'-methylenedioxy)phenylethyl-L-glutathione (11b), S-2,2-diethoxycarbonyl-1-(3',4',5'-trimethoxy)phenylethyl-L-glutathione (11c), S-2,2-diethoxycarbonyl-1-(4'-hydroxy)phenylethyl-L-glutathione (11d), S-2,2-diethoxycarbonyl-1-(4'-methoxy)phenylethyl-L-glutathione (11e) were obtained in good yields. The structure of the adducts was characterized by analytical and spectral data. The effects of pH and solvents upon the yields were also briefly examined. In the range of pH from 4.0 to 8.0, the aqueous methanol were found to be the best solvent for the addition reaction and the antibacterial activities of the adducts to Gram(+) bacteria were found to be weak.

• KSBB Journal
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• v.17 no.3
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• pp.311-313
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• 2002

Lactobacillus spry. are Gram-positive bacteria playing important roles in human health. In this study, we successfully isolated the total RNA from the cells broken by glass beads using hot phenol method. Moreover, we were able to omit lysozyme and proteinase K treatment by using glass beads to break cell more efficiently. This method was more rapid and simple when compared to the previous one. Prepared RNA can be used for the transcriptional analysis of Lactobacillus spp.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10a
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• pp.157-160
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• 2000

다중 워터마킹은 하나의 컨텐츠에 2개 이상의 다른 워터마크를 삽입하는 것으로 각 워터마크는 유일한 키로 정확하게 추출할 수 있어야 한다. 대역확산법(spread spectrum)을 이용한 다중 워터마킹은 삽입되는 워터마크간의 직교성(orthogonality)이 제공되어야 삽입된 워터마크들의 정확한 추출이 가능하다. 랜덤계열과 Hadamard 계열을 이용한 기존의 방법은 직교성이 보장되지 않기 때문에 워터마크가 정확히 추출되지 않은 문제가 발생한다. 따라서, 본 논문에서는 랜덤계열들을 Gram-schmidt 직교화 과정을 이용하여 직교화시킨 후, 직교화 된 랜덤계열로 워터마크를 삽입하여 정확한 추출이 가능한 방법을 제안하였다.

• Journal of Dairy Science and Biotechnology
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• v.38 no.1
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• pp.37-44
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• 2020

The antimicrobial activity of the ethanol extract of Hibiscus sabdariffa L. (Roselle) powder against various food-borne pathogens was tested using the lawn diffusion assay. The results showed that the ethanol extract exhibited antimicrobial activities against Staphylococcus aureus (total inhibition), Salmonella enteritidis (partial inhibition), Listeria monocytogenes (partial inhibition), Escherichia coli (partial inhibition), Cronobacter sakazakii (partial inhibition), and Bacillus cereus (partial inhibition). Therefore, it is strongly recommended that Hibiscus sabdariffa L. (Roselle) should be considered for use as a natural food-grade additive for the inhibition of various food-borne pathogens, including both gram-positive and gram-negative pathogens, and the improvement of the overall quality of various dairy products, including milk.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.1
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• pp.1-5
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• 2005

This study investigated and compared chemical properties and biological activities of four commercial sikhae products (three flat-fish, Pleuronectes herzensteini, Sikhae: product A, B, C; one Alaska pollack, Theragra chalcogramma, Sikhae: product D) and Alaska pollack Sikhae (product E). Total acidity, amino nitrogen, salinity and pH in all products were in ranges of $0.47-1.93\;g\%$, $145.94-204.81\;mg\%$, $3.40-4.00\%$ and 4.38-5.55, respectively. All products showed antimicrobial activities against Bacillus ceraus subtilis, B. cereus, Staphylococcus aureus, Listeria monocytogenes, Vibrio parahaemolyticus, except for Salmonella typhimurium. Particularly the activities were more effective with gram positive bacteria than gram negative bacteria. Antioxidative $(EDA_{50};\;14.20\;mg/mL)$ and Fibrinolytic (0.95 plasmin unit/mL) activities of product E were much stronger than commercial Sikhae products (EDA50; 18.87-34.60 mg/mL and 0.69-0.85 plasmin unit/mL).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.4
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• pp.377-387
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• 2021

Fecal contamination levels of discharge water from inland pollution sources were investigated in Iwon-myeon (Taean-gun), South Korea. Gram-negative bacteria were isolated during the investigation and the antimicrobial resistance patterns of the isolates were examined to estimate their impact on the coastal environment. The ranges of total coliform and fecal coliform of 12 samples from four major inland pollution sources were 79-490,000 MPN/100 mL and 2.0-490,000 MPN/100 mL, respectively, with the highest level of fecal contamination at Station No. 3. A total of 137 strains (14 genus) were isolated, of which 86 strains (62.8%) were Enterobacteriaceae. The identified isolates were as follows: Pseudomonas spp. (35 strains), Klebsiella spp. (20 strains), Serratia spp. (20 strains), and Escherichia spp. (19 strains). The isolated Gram-negative bacteria showed the highest antimicrobial resistance to ampicillin (81.8%), followed by amoxicillin/clavulanic acid (64.2%), ceftiofur (61.3%), and cefoxitin (59.1%). Antimicrobials in which less than 10% of isolates showed antimicrobial resistance were ciprofloxacin (3.6%) and gentamicin (2.2%). Resistance to one or more antimicrobials was observed in 121 strains (88.3%) and 84 strains (61.3%) showed a tendency for multiple antimicrobial resistance.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.435-439
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• 2019

An efficient one pot multicomponent synthesis of pyrimidinone derivatives of Biginelli type is described. 4-amino-6-aryl-pyrimidine-5-carbonitrile molecules were synthesized efficiently via three-component Biginelli-type condensation of aldehyde, malononitrile, and semicarbazone as urea substituent in the presence of a catalytic amount of PEG-400 as green medium under microwave irradiation. The reactions proceeded efficiently in the presence of microwave radiation to afford the desired products in good to excellent yields. Products have been confirmed by IR, and NMR spectral analysis. All the molecules were tested for their antimicrobial activity against E. coli, S. aureus, P. aeruginosa and C. tropicalis. Some of the compounds have shown moderate to good inhibition efficiency against both gram-positive and gram-negative bacteria. The potent activity was observed against the fungal species with minimum inhibition concentration 12.5 ㎍/mL.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.65-71
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• 1995

Bacteriocins from lactic acid bacteria have attracted much attention in recent years because of their useful worth in increasing safety and extending shelf life of foods. These substances show an inhibitory effect against some food spoilage bacteria and food-borne pathogens. The inhibitory effect fo the bacteriocin produces by lactic acid bacteria against Listeria monocytogenes(L. monocytogenes) was examined in this study. The culture supernatants of 5 kinds of bacteria among the 10 kinds of testes lactic acid bacteria had the inhibitory activity against Listeria sp., various Gram positive and Gram negative bacteria. Bacteriocin produced by Lactobacillus plantarum(Lact. plantarum) LMG 7945 was the most active toward L. monocytogenes. Bacteriocin production of the Lact. plantarum LMG 7945 cultured on MRS broth was increased late logarithmic phase over early stationary phase. This bacteriocin was stable at heat treatment and acidic pH relatively; The activity was retained after heating at 121$^{\circ}C$ for 15min and was active in the pH range of 2~4 but was lost above pH 5.