• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.1
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• pp.15-18
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• 1978

For a general ingredients analysis and E Coli-form bacteria surveyed on the marketed milk, samples of bottled milk produced by four different companies were collected in Cholla Buk-do area and examined. The results are: 1) In water content samples A and C exceeded the standard slightly whereas B and D were good. 2) The contents of crude fat and crude protein of all samples were slightly higher than the standard. 3) All samples were deficient in contents of the crude ash and lactose. 4) In spite of the winter, all samples contained more coli-form bacteria than the standard allowance. Through the above results, it could be seen that all samples of marketed milk were a little poor in the contents of general ingredients and contained more coli-form bacteria than the standard allowances. Therefore, considering the general trends of increasing milk consumption and its influence on the national public health. it is necessary for the milk manufacturer to try to streng hen the scientific inspection and improve, the handling of milk products during the distribution.

• Journal of Magnetics
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• v.18 no.3
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• pp.289-296
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• 2013

This work presents results of the study which concerns the influence of the rotating magnetic field (RMF) on the growth rate, cell metabolic activity and ability to form biofilms by E. coli and S. aureus. Liquid cultures of the bacteria were exposed to the RMF (RMF frequency f = 1-50 Hz, RMF magnetic induction B = 22-34 mT, time of exposure t = 60 min, temperature of incubation $37^{\circ}C$). The present study indicate the exposition to the RMF, as compared to the unexposed controls causing an increase in the growth dynamics, cell metabolic activities and percentage of biofilm-forming bacteria, in both S. aureus and E. coli cultures. It was also found that the stimulating effects of the RMF exposition enhanced with its increasing frequencies and magnetic inductions.

• Journal of Korean Biological Nursing Science
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• v.23 no.1
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• pp.1-10
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• 2021

Purpose: To verify the anti-microbiotic activity and to develop eco-friendly surface disinfectants using the Opuntia ficus-indica extract. Methods: The stem and fruits of the Opuntia cultivated in Jeju Island were extracted with hot water, 70% EtOH and 100% MeOH, respectively. To examine the antimicrobial activity of the extracts, gram positive bacteria (Bacillus subtilis, Staphylococcus aureus), gram negative bacteria (Escherichia coli, Salmonella typhimurium), yeast (Candida albicans), mold (Aspergillus flavus) and antibiotic resistant bacteria (E. coli, S. aureus) were measured to form a clear zone. Results: The antibacterial activity of the fruit extract was higher than that of the stem extract, and the antibacterial activity of the 100% MeOH (FM) extract and the 70% EtOH (FE) extract of the palm cactus fruit was suitable for the surface disinfectant overall, and clear-zone formed even at relatively low concentrations (250 mg/mL). The FM and FE have antibacterial activity against various bacteria, therefore they can be used as disinfectants. Conclusion: The antimicrobial activity of Opuntia ficus-indica extract from Jeju Island by stem and fruit was determined at relatively low concentrations (250 mg/mL). The Opuntia ficus-indica extract will be useful for surface disinfectants dissolving the patients' bath, oral gargling, and powdered powder in water or ethanol in appropriate concentrations.

• Archives of Pharmacal Research
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• v.24 no.4
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• pp.263-269
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• 2001

Diazepamoxadiazoles 4,5,6,12,14 and 22 were prepared with the binary form system. Diazepamthiadiazoles 15,20 and Diazepamtriazoles 7,8,9,17,18,19 and 21 were also shapely synthesized. Some of these compounds were screened to test their antibacterial activity against E. coli and B. subtilis compounds 15 and 20 show potent activity against these bacteria.

• Journal of Food Hygiene and Safety
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• v.10 no.1
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• pp.45-51
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• 1995

Ozone treatment was applied to ginseng powder for the improving hygienic quality of ginseng powder. A bacterial strain was isolated form ginseng powder contaminated. The strain designated as GT4, was identified as Escherichia coli species by IMVIC test method. Ozone inhibited strongly total bacteria and coliforms in ginseng powder(initial concentration 103/g) at 0.35 ppm. High ozone concentration reduced death time of the total bacteria in ginseng powder. However, ozone treatment caused significant degradation in saponins of ginseng powder. Ozone treatment also caused a increase in Hunter's color L value and decrease in a and b values of ginseng powder.

• Korean Journal of Agricultural Science
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• v.41 no.3
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• pp.245-249
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• 2014

Among dozens of DNA polymerases cloned from thermophilic bacteria, Taq DNA polymerase from Thermus aquaticus has been most frequently used in polymerase chain reaction (PCR) that is being applied to gene cloning, DNA sequencing, gene expression analysis, and detection of infectious and genetic diseases. Since native Taq DNA polymerase is expressed at low level in T. aquaticus, recombinant Escherichia coli system was used to produce Taq DNA polymerase in a large amount. Taq DNA polymerase was expressed as a soluble form under the control of tac promoter in E. coli, and purified by heat treatment and ion exchange chromatographies. The purified Taq DNA polymerase was nearly homogeneous and exhibited a similar DNA amplification activity with a commercial Taq DNA polymerase.

• Biomedical Science Letters
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• v.13 no.1
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• pp.71-73
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• 2007

For the rapid detection of objective pathogenic bacteria from colon biopsy specimens, multiplex PCR (polymerase chain reaction) method was developed. The major objective bacteria in this study were Shiga-like toxin producing E. coli O157:H7, Staphylococcus aureus, Vibrio parahaemolyticus, Listeria monocytogenes, Shigella spp. Salmonella spp. and Yersinia spp.. To detect simultaneously 7 kinds of pathogenic bacteria in single reaction tube, multiplex PCR system was executed using 6 sets of primers used in single PCR system for the respective bacteria. The results in this research might be applied for the detection of pathogenic bacteria form colon biopsy samples.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.98-104
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• 1998

As an efffort ot construct LAB (latice acid bacteria), capable of utilizing starch as fermentation substrate without the aid of externally supplied enzymes, plasmid vectors containing the amyL($\alpha$-amylase/pullulansase gene) from Clostridium thermophydrosulfuricum, and glucoamylase cDNA from Asperigillus shirousamii were constructed and introduced itno E. coli and L. lactis. For expression in procaryotes , 1.9kb glucoamylase cDNA encoding the mature form of enzyme was PCR amplified and translationaly fused to a PCR amplified 260 bp fragment containing the promotor and secretion signals of amyl in the same reading frame. The production of $\alpha$-amylase, Apu, and glucoamlase in E. coli and L. lactis was confirmed by enzyme assay and zymography . Enzymeswere detected in both cellpellets and supernatants, indicating theworking of scretion signals in heterologous hosts. The efficiencies of secretion were varibale depending on the gene and host. The highest $\alpha$- amylase acitivity observed was 1.1 units and most activiity was detected from thecell pellets. The degree of gene expression in both hosts and the effect on the growth of hosts were examined.

• BMB Reports
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• v.37 no.1
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• pp.83-92
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• 2004

As a result of the enormous amount of information that has been collected with E. coli over the past half century (e.g. genome sequence, mutant phenotypes, metabolic and regulatory networks, etc.), we now have detailed knowledge about gene regulation, protein activity, several hundred enzyme reactions, metabolic pathways, macromolecular machines, and regulatory interactions for this model organism. However, understanding how all these processes interact to form a living cell will require further characterization, quantification, data integration, and mathematical modeling, systems biology. No organism can rival E. coli with respect to the amount of available basic information and experimental tractability for the technologies needed for this undertaking. A focused, systematic effort to understand the E. coli cell will accelerate the development of new post-genomic technologies, including both experimental and computational tools. It will also lead to new technologies that will be applicable to other organisms, from microbes to plants, animals, and humans. E. coli is not only the best studied free-living model organism, but is also an extensively used microbe for industrial applications, especially for the production of small molecules of interest. It is an excellent representative of Gram-negative commensal bacteria. E. coli may represent a perfect model organism for systems biology that is aimed at elucidating both its free-living and commensal life-styles, which should open the door to whole-cell modeling and simulation.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.645-655
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• 2020

Bacteria are a very common cause of food poisoning. Moreover, bacteria form biofilms to protect themselves from harsh environments. Conventional detection methods for foodborne bacterial pathogens including the plate count method, enzyme-linked immunosorbent assays (ELISA), and polymerase chain reaction (PCR) assays require a lot of time and effort. Hyperspectral imaging has been used for food safety because of its non-destructive and real-time detection capability. This study assessed the feasibility of using hyperspectral imaging and machine learning techniques to detect biofilms formed by Escherichia coli. E. coli was cultured on a high-density polyethylene (HDPE) coupon, which is a main material of food processing facilities. Hyperspectral fluorescence images were acquired from 420 to 730 nm and analyzed by a single wavelength method and machine learning techniques to determine whether an E. coli culture was present. The prediction accuracy of a biofilm by the single wavelength method was 84.69%. The prediction accuracy by the machine learning techniques were 87.49, 91.16, 86.61, and 86.80% for decision tree (DT), k-nearest neighbor (k-NN), linear discriminant analysis (LDA), and partial least squares-discriminant analysis (PLS-DA), respectively. This result shows the possibility of using machine learning techniques, especially the k-NN model, to effectively detect bacterial pathogens and confirm food poisoning through hyperspectral images.