• Journal of Dairy Science and Biotechnology
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• 제39권2호
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• pp.68-77
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• 2021

This study aimed to evaluate the effects of antibacterial activity of Tibetan mushroom exopolysaccharide against foodborne pathogenic bacteria Staphylococcus aureus 305, Listeria monocytogenes ATCC19114, Escherichia coli O157:H7 ATCC42894 and Escherichia coli O55. The yield of exopolysaccharide isolated from Tibetan mushroom culture was 620 mg/L. The antibacterial activity of exopolysaccharide against foodborne pathogenic bacteria exhibited 15 mm and 12 mm clear zone against S. aureus 305 and L. monocytogenes ATCC 19114, respectively. However, no clear zone was observed against E. coli O157:H7 ATCC 42894 and E. coli O55. In conclusion, exopolysaccharide isolated from Tibetan mushroom culture have the antibacterial activity only against Gram-positive foodborne pathogenic bacteria.

• Biomedical Science Letters
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• 제17권3호
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• pp.173-176
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• 2011

Free-living Acanthamoeba are eukaryotic protozoan organisms that are widely distributed in the air, water, etc such as environment. Acanthamoeba ingest the Escherichia coli which will replicate in cytoplasm of Acanthamoeba. Bacterial pathogenicity or virulence is one of important determinant factors to survive in free-living Acanthamoeba and otherwise Acanthamoebic pathogenicity is also an important factor for their interactions. Bacterial association with pathogenic strain of Acanthamoeba T1 and T4 was lower about two times than non-pathogenic T7. Bacterial invasion percentages into T1 were higher about three times than T7 but bacterial survival in T7 was increased as T1. The capsule-deletion mutant exhibited limited ability for invasion/uptake by and survival inside pathogenic Acanthamoeba T4. E. coli-outer membrane protein A (OmpA) decreased bacterial association with A. castellanii by about three times and it had higher effects than lipopolysaccharides (LPS). Under favorable conditions, the mutants were not survived in Acanthamoeba up to 24 h incubation. Therefore, this review will report pathogenic and non-pathogenic Acanthamoeba strains interactions with E. coli and its several mutants, i.e., capsule, OmpA and LPS.

• Food Science and Preservation
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• 제5권3호
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• pp.286-291
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• 1998

The sensitivity of various pathogenic bacteria(Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus 196E, Salmonella typhimurium) to the water extract of green tea was tested. Tryptic soy broth was inoculated with 10$\^$5/CPU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 30 hours. The extract was added at a final concentration of 0-2%(w/v) into culture broth at the mid or late exponential phase of bacteria. The growth of pathogenic bacteria was inhibited with increasing concentrations of the extract in culture broth and the late exponential phase cells were more resistant than the mid exponential phase cells. Cram positive bacteria(L. monocytogenes and S. aureus 196E) were more sensitive than Cram negative bacteria(E. coli O157:H7 and S. typhimurium). S. aureus had the highest sensitivity, followed by L monocytogenes, E. coli O157:H7. S. typhimurium was the most resistant to the water extract of green tea.

• Journal of Food Hygiene and Safety
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• 제8권3호
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• pp.141-145
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• 1993

Thirty nine kinds of Korean herb drugs have screened for antimicrobial activity of some pathogenic microorganisms. It was revealed that some of hot water extracts from herb drugs showed antimicrobial activity in one or more strain of pathogenic microorganisms. Phellodendron amurense and Coptis chinensis inhibited growth of Staphylococcus aureus. Rubus coreanus showed antibacterial activity in Staphylococcus aureus and Pseudomonas aeruginosa. Citrus unshill inhibited growth of Escherichia coli and Cornus officinalis showed antibacterial activity in E. coli and Pseudomonas aeruginosa. Dioscorea battltas and Cinnamomum cassia showed antibacterial activity in Pseodomonas aeruginosa. And also, ScutelJa baicaJerrsis inhibited growth of Candida albicanus. Achyranthes japonica and Glycyrrhiza uralensis showed antifungal activity in Aspergillus niger. It was noteworthy that Glycrrhiza uranensis inhibited growth of Staphylococcus aureus, E. coli, Pseudomonas aeruginosa and Aspergillus niger.

• Food Science and Preservation
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• 제5권4호
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• pp.380-385
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• 1998

The sensitivity of various pathogenic bacteria(Aeromonas hydrophila, Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus 196E, Salmonella typhimurium) to the ethanol extract of pine needle was tested. Tryptic soy broth containing 0-2%(w/v) of the ethanol extract of pine needle was inoculated with 10$^4$-10$\^$6/ CFU/ml of pathogenic bacteria and incubated at 35$^{\circ}C$ for 48 hours. Gram positive bacteria(L. monocytogenes and S. aureus 196E) and 1 Gram negative bacteria(A. hydrophila) were more sensitive than E. coli O157:H7 and S. typhimurium in the ethanol extract of Pine needle. Gram negative bacteria(E. coli O157:H7 and S. typhimurium) were not inhibited at 1% and they were slightly inhibited at 2% ethanol extract of pine needle. S. aureus was the highest sensitivity, followed by A. hydrophila, L. monocytogenes E. coli O157:H7 in that order. S. typhimurium was the most resistant to the ethanol extract of pine needle.

• The Journal of the Korean Society for Microbiology
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• 제21권4호
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• pp.417-422
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• 1986

The specimens were collected from 89 diarrheal patients who had visited Pusan National University Hospital from June to September 1985. They were cultured and tested for the bacteriological identification of causative agents. In this study we identified 5 strains of Salmonella species, 5 strains of Shigella species, 2 strains of Y. enterocolitica, and 17 strains of enteric pathogenic E. coli. Enteric pathogenic E. coli were classified into enterotoxigenic E. coli, enteropathogenic E. coli, and enteroinvasive E. coli by serological type. We tried to isolate V. cholerae and V. parahaemolyticus too but we cannot find them out.

• Korean Journal of Veterinary Service
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• 제16권2호
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• pp.150-156
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• 1993

The present study was conducted to investigate the biochemical characteristics and anti-biotic resistance of pathogenic Escherichia coli (E. coli) isolated from piglets with diarrhea in Kyongbuk Western Area during the period from February to November 1992. 55 E. coli strains were isolated from 97 piglets with diarrhea and the biochemical and cultural reaction were compared with the classification criteria of Edwards and Ewing. The majority of E. coli were susceptible to amikacln, enrofloxacin and gentamicin. 51 (92.7%) out of 55 drug resistance stains carried R factor (R+) which were transferable to the recipients by conjugation.

• Journal of Food Hygiene and Safety
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• 제31권6호
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• pp.393-398
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• 2016

The objective of this study was to isolate pathogenic Escherichia coli from fresh vegetables with selective media and Petrifilm, and identify a suspicious colony using biochemical identification. Twenty gram of lettuce, twenty gram of cabbage and ten gram of sprout were prepared, and a 5-strain mixture of pathogenic E. coli (Enterohemorrhagic E. coli NCCP11142, Enterotoxigenic E. coli NCCP14037, Enteropathogenic E. coli NCCP14038, Enteroaggregative E. coli NCCP14039, Enteropathogenic E. coli NCCP15661) was inoculated to obtain 1, 2 and 3 log CFU/g. Eighty to ninety milliliter of buffered peptone water (BPW) was placed and pummeled for 60 s. As a results, the Petrifilm method was all positive, but enrichment method of qualitative analysis was negative except for 3-log CFU/g inoculated lettuce. Regarding biochemical identification of pathogenic E. coli, the identification rates were dependent on type of methods and vegetables; lettuce: API 20E 100% (44/44), Microgen GNA 100% (44/44) and Food System 66.7% (10/15), cabbage: API 20E 64.7% (22/34), Microgen GNA 50% (16/32) and Food System 60% (9/15), sprout: API 20E 65.1% (28/43), Microgen GNA 62.3% (27/43) and Food System 53.3% (8/15). These results could be useful in determining an appropriate method to detect pathogenic E. coli in fresh vegetables.

• Journal of Korean Society of Environmental Engineers
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• 제32권11호
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• pp.1063-1068
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• 2010

This study compared UV and UV/$H_2O_2$ inactivation of E.coli, a possible indicator microorganism for fecal contamination of water, and $Q{\ss}$ phage, an indicator for pathogenic viruses. UV inactivation of $Q{\ss}$, T4 and lambda phages in actual secondary effluent was investigated, too. As a result, similar inactivation efficiency between $Q{\ss}$ phage and E.coli was observed during UV treatment, while $Q{\ss}$ phage showed higher resistance to UV/$H_2O_2$ than E.coli. $Q{\ss}$ phage resistance to UV or UV/$H_2O_2$ does not reflect those of all pathogenic viruses. However, the result tells that the use of E.coli inactivation efficiency in evaluating microbiological safety of water could not always ensure the sufficient safety from pathogenic viruses. Meanwhile, $Q{\ss}$ phage showed less resistance to UV than T4 and lambda phages, indicating that the use of $Q{\ss}$ phage as an indicator virus may bring insufficient disinfection effectiveness by causing the introduction of lower UV dose than required. Consequently, it can be thought that T4 or lambda phages would be more desirable indicators in ensuring the sufficient disinfection effectiveness for various pathogenic viruses.

• The Korean Journal of Food And Nutrition
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• 제26권1호
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• pp.132-136
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• 2013

Antimicrobial resistance and multi-drug resistance patterns have been carried out on total of 210 isolated of Salmonella spp. and pathogenic E. coli isolated from food poisoning patients on January through December 2012 in Incheon, Korea. The highest percentage of antibiotics resistance was found to the following antimicrobial agents: tetracycline 43.8%, ampicillin 34.8%, nalidixic acid 23.8%, sulfamethoxazole/trimethoprim and chloramphenicol 12.4%, and ampicillin/sulbactam 11.4%. The highest percentage of resistance was 37.5% to ampicillin for Salmonella spp. and 59.0% to tetracycline for pathogenic E. coli. Overall the multidrug resistance rates of 1 drug was 26.2%, 2 drugs 9.0%, 3 drugs 9.5%, 4 drugs 7.1%, and 5 or more drugs 12.46%. The multi-drug (MDR) strains to four or more antimicrobial agents among the resistant organisms were quite high: 15.9% and 22.1% for Salmonella spp. and pathogenic E. coli, respectively. The study implies that limitation of unnecessary medication use is pertinent in order to maintaining the efficacy of drugs.