• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.414-417
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• 1992

In order to study the addition effect of Leuconostoc mesenteroides and nisin on Escherichia coli and lactic acid bacteria during fermentation and storage of Kimchi, Kimchi was stored at 4$^{\circ}C$ for 7 days and then in-creased the temperature to $25^{\circ}C$. Lactic acid content on Kimchi fermentation at 4$^{\circ}C$ was maintained initial content which was increased upto 0.9% and lactic bacteria was also increased after switching to $25^{\circ}C$. E. coli, on the other hand, was a little decreased from the initial level, but a significant decrease was found for the those Kimchi of Leuconostoc muenteroides added and nisin treated group when the fermentation temperature was switched to $25^{\circ}C$.

• Journal of Animal Science and Technology
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• v.59 no.2
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• pp.4.1-4.5
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• 2017

Background: Biofilms were the third-dimensional structure in the solid surface of bacteria. Bacterial biofilms were difficult to control by host defenses and antibiotic therapies. Escherichia coli (E. coli) and Salmonella were popular pathogenic bacteria that live in human and animal intestines. Essential oils are aromatic oily liquids from plant materials and well known for their antibacterial activities. Method: This study was conducted to determine effect of essential oil on anti-biological biofilm formation of E. coli and Salmonella strains in in vitro experiment. Two kinds of bacterial strains were separated from 0.2 g pig feces. Bacterial strains were distributed in 24 plates per treatment and each plates as a replication. The sample was coated with a Bacterial biofilm formation was. Result: Photographic result, Escherichia coli (E. coli) and Salmonella bacteria colony surface were thick smooth surface in control. However, colony surface in blended and single essential oil treatment has shown crack surface layer compared with colony surfaces in control. Conclusion: In conclusion, this study could confirm that essential oils have some interesting effect on anti-biofilm formation of E. coli and Salmonella strains from pig feces.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.415-419
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• 2006

The epoxide hydrolase (EH) of Rhodotorula glutinis which has a high enantioselectivity against aromatic epoxide substrates was expressed to high levels in Escherichia coli based on codon usage. We analysed the Preference of codon usage between the yeast, R. glutinis, and bacteria, E. coli. E. coli, Rosetta(DE3)pLysS, harbors pRARE plasmid with tRNA genes for rare-codons was employed as a host strain. The recombinant E. coli expressing R. glutinis EH showed an enhanced enantioselective hydrolysis activity toward racemic styrene oxide. Enantiopure (S)-styrene oxide with a high enantiopurity of 99% ee (enantiomeric excess) was obtained from racemic substrates.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.6
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• pp.634-639
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• 2006

The simulation of electric field distribution of discharge tube with globular $Al_2O_3$ and the removal characteristic of Escherichia coli by the discharge tube with globular $Al_2O_3$ were estimated. The removal characteristic of Escherichia coli was related to the input voltage because the electric field is increased according to input voltage. As the passing amount of test water in discharge tube is increased, the removal ratio of Escherichia coli was increased because passing numbers of electric field section is increased. As the particle size of globular $Al_2O_3$ increased, the removal time of Escherichia coli was shortened due to the dielectric polarization of globular dielectric $Al_2O_3$. Also, the removal efficiency of Escherichia coli for the discharge tube with globular dielectric $Al_2O_3$ was higher than that of the discharge tube without it.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.526-531
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• 2006

Minimum inhibition concentration(MIC), growth inhibition activity, and colony forming inhibitory activity of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enterifidis and Serratia marcescens were tested. MIC of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis and Serratia marcescens was 12.5, 12.5, 12.5, 50, 50, 100ppm, respectively. Growth inhibition concentration of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis and Serratia marcescens was below 1.0, 6.25, below 1.0, 6.25, 25, 25ppm, respectively. Colony forming inhibitory activity of grapefruit seed extract against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis and Serratia marcescens was 93.9, 94.0, 99.9, 4.4, 82.7, 86.4%, respectively. Colony forming inhibitory activities of grapefruit seed extract against Gram positive bacteria were higher than that against Gram negative bacteria.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.668-674
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• 2020

Manuka honey (MH) has been shown anti-bacterial activity against several pathogenic bacteria. However, the inhibitory effect of MH on biofilm formation by Escherichia coli O157:H7 has not yet been examined. In this study, MH significantly reduced E. coli O157:H7 biofilm. Moreover, pre- and post-treatment with MH also significantly reduced E. coli O157:H7 biofilm. Cellular metabolic activities exhibited that the viability of E. coli O157:H7 biofilm cells was reduced in the presence of MH. Further, colony forming unit of MH-treated E. coli O157:H7 biofilm was significantly reduced by over 70%. Collectively, this study suggests the potential of anti-biofilm properties of MH which could be applied to control E. coli O157:H7.

• BMB Reports
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• v.32 no.2
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• pp.168-172
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• 1999

We previously reported that a novel thiol peroxidase (p20) from Escherichia coli is a distinct periplasmic peroxidase that detoxifies hydroperoxides together with glutathione or thioredoxin. Until now, there was no experimental evidence for the presence of thioredoxin (Trx) in the periplasmic space. In an attempt to confirm the physiological function of p20 as a thiol peroxidase supported by Trx in the periplasmic space, we have purified a Trx activity from the periplasmic space of Escherichia coli and identified the Trx as the same protein as the cytoplasmic Trx. The presence of Trx in the periplasmic space of Escherichia coli suggests that p20 is a unique extracellular Trx-linked thiol peroxidase.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.529.1-529
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• 1986

For isolation of the CMCase gene of the alkalophilic Bacillus sp. strain N-4 to analyze their genetic information for the multicomponents of the cellulase, Bscherichia coli K12 and plasmid DNA pBR322 was used as host-vector system. After the digestion of purified chromosomal DNA and plasmid DNA pBR322 with HindIII, these were ligated. The ligated DND were transformed into Escherichia coli, and recombinant plasmid 107 carried the gene coding for CMCase was constructed. The CMCase produced by Escherichia coli cells containing plasmid DNA pYBC107 was found in the cells as intracellular enzyme and nearly 60% of the total CMCase activity was localized in cellular fraction. Also, the optimum pH for the reaction of CMCase produced by Escherichia coli was appeared at pH .8.0 and the enzyme was stable between pH 7.0 and pH 8.0.

• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.193-202
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• 2002

The polymerase chain reaction(PCR) of target lacZ and uidA genes were used to detect total coliform and Escherichia coli for determining water quality, respectively. Of 109 spring waters, coliform were detected from 38 spring waters by lacZ PCR method but 21 spring waters by culture method accepted by the Ministry of Environment for water quality monitoring. The lacz PCR method gave the results statistically equivalent to those of the culture method(kappa=0.62, McNemar=17.00). The uidA PCR method gave the same results to those of the culture method. The sensitivity and specificity of coliform and E. coli by PCR method were 100% and 80.7%, respectively. Therefore, PCR can be used for the rapid identification of Escherichia coli and coliform in potable water using uidA and lacZ.

• Food Science and Preservation
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• v.7 no.1
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• pp.124-131
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• 2000

Antibacterial activities of powdered spices(garlic , ginger, cinnamon and clove) against pathogenic Escherichia coli )157:H7 and Staphyloccus auresus were investigated. Spice powder was added in was exponetial phase of each bacterial culture . Growth inhibition was determined by the absorbance at 660nm and morphological changes of the cells were observed by transmission electron microscope (TEM). Ginger powder has the highest antibacterial activity, following cinnamon , clove and garlic has the least activity.Growth of Escherichia coli O157:H7 and Staphyloccus aureus were completely inhibited within 5 hours after addition of 1 % of garlic , 0.3% of ginger or cinnamon , 0.5% of clove powder on the exponential phase of the cells. Spice untreated cells of E. coli and S. aureus, the cytoplasm was entirely surrounded by rigid cell wall and cell walls formed a smooth layer well attached to the plasma membrane. In the cells of E. coli and S. aureus treated with spice powder, cell wall and plasma membrane were lysed and severely damaged. E.coli cells growth in the presence of spice powder showed plammolysis, the loss of electron dense material, the formation of extra cellular blebs and cytoplasm burst out from the cell. S .sureus cells grown in the presence of spice powder showed swell of cell wall, the loss of electron dense material , coagulation of cell cytoplasm and formation of extra cellular blebs. Severely damaged cells of S. aureus lost whole cytoplasm and left as ghost of the cell. Spice powder stimulated autolyssi and induced cell death.