• The Plant Pathology Journal
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• v.31 no.1
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• pp.1-11
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• 2015

Antimicrobial cyclic peptides derived from microbes bind stably with target sites, have a tolerance to hydrolysis by proteases, and a favorable degradability under field conditions, which make them an attractive proposition for use as agricultural fungicides. Antimicrobial cyclic peptides are classified according to the types of bonds within the ring structure; homodetic, heterodetic, and complex cyclic peptides, which in turn reflect diverse physicochemical features. Most antimicrobial cyclic peptides affect the integrity of the cell envelope. This is achieved through direct interaction with the cell membrane or disturbance of the cell wall and membrane component biosynthesis such as chitin, glucan, and sphingolipid. These are specific and selective targets providing reliable activity and safety for non-target organisms. Synthetic cyclic peptides produced through combinatorial chemistry offer an alternative approach to develop antimicrobials for agricultural uses. Those synthesized so far have been studied for antibacterial activity, however, the recent advancements in powerful technologies now promise to provide novel antimicrobial cyclic peptides that are yet to be discovered from natural resources.

• Korean Journal of Veterinary Research
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• v.22 no.2
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• pp.161-165
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• 1982

Biochemical and antimicrobial susceptibility tests were conducted on 40 strains of Pseudomonas aeruginosa originated from diseased chicken submitted for diagnosis to this Institute during 1978-80. An extensive study of the biochemical properties revealed that the tested strains can be identified with Pseudomonas aeruginosa. Antibiogram showed that all the strains were susceptible to gentamicin, colistin and amikacin but resist to nitrofurantoin, trimethoprim+sulfamethoxazole, ampicillin, methicillin and kanamycin, and had varing degreed of resistance to other antimicrobials including carbenicillin, sulfomamides, neomycin, streptomycin, tetracycline and chloramphenicol. Three of the most frequent resitance patterns observed were FM SXT AM ME KM CM TC SM NE SSS Pattern, FM SXT AM ME KM CM TC SM NE SSS CB Pattern and FM SXT AM EKM CM TC SM Pattern, and these resistance patterns contained 72.5% of the tested strains.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.563-568
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• 2005

The present study was conducted to investigate biochemical characteristics and antimicrobial susceptibility of Aeromonas hydrophilia isolated from Jackass penguins (Spheniscus demersus) of zoo and capelins (Mallotus villosus). Seven of Jackass penguins showed anorexia, depression with seriously greenish vomiting for a few days, but resulted in 4 deaths although extensive treatment was carried out by zoo veterinarians. From the 18 samples composed of organs or feces from dead or live Jackass penguins and capelins, 4 (22.2%) Aeromonas hydrophilia were isolated and Bacillus spp, Staphylococcus aureus, Staphylococcus auricularis, Staphylococcus cohnii and Enterobacter aminigenus were also identified. Antimicrobial susceptibility tests of Aeromonas hydrophilia showed that all isolates were susceptible to amikacin, gentamicin, kanamycin, norfloxacin and trimethoprim- sulfadimethoxazole. However, all isolates were resistant to the following antimicrobials; ampicillin, bacitracin, c ephalothin, cefazolin, noboviocin, penicillin and vancomycin.

• Korean Journal of Veterinary Research
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• v.56 no.2
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• pp.109-111
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• 2016

The present study was conducted to determine the antibiotic susceptibilities of local Mycoplasma hyopneumoniae (Mhp) and Mycoplasma hyorhinis (Mhr) filed isolates. Minimum inhibitory concentrations (MICs) of Mhp and Mhr field isolates (twelve each) obtained from enzootic pneumonia-like lung lesions during 2009-2011 from Korea were determined using the broth microdilution method. Tylvalosin showed the highest activity against Mhp and Mhr field isolates, with $MIC_{90}$ values of $0.06{\mu}g/mL$ and $0.12{\mu}g/mL$, respectively. Therefore, Korean Mhp and Mhr isolates are highly susceptible to tylvalosin.

• Applied Chemistry for Engineering
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• v.27 no.6
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• pp.565-572
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• 2016

While there have been great demands on improving domestic water pollution issues, the necessity for real time monitoring of particular drug residues in water resources has been raised since drug residues including antibiotics could provoke new trains of drug-resistant bacteria in water environments. Among many different types of drugs used for pharmaceutical treatment, antibiotics are considered to be one of the most hazardous to our ecosystem since they can rapidly promote the spreading of drug-resistant bacteria in water environments. In this mini-review, we will highlight recent developments made on creating in-situ sensing platforms for the fast monitoring of antibiotic residues in aquatic environmental samples focusing on optical and electrochemical techniques. Related recent technology developments and the resulting economy effects will also be discussed.

• Safety and Health at Work
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• v.3 no.2
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• pp.85-91
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• 2012

The occupations involved in food animal production have long been recognized to carry significant health risks for workers, with special attention to injuries. However, risk of pathogen exposure in these occupations has been less extensively considered. Pathogens are a food safety issue and are known to be present throughout the food animal production chain. Workers employed at farms and slaughterhouses are at risk of pathogen exposure and bacterial infections. The industrialization of animal farming and the use of antimicrobials in animal feed to promote growth have increased the development of antimicrobial resistance. The changed nature of these pathogens exposes workers in this industry to new strains, thus modifying the risks and health consequences for these workers. These risks are not yet recognized by any work-related health and safety agency in the world.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.63-76
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• 1992

A study on the isolation of Yersinia from the feces of healthy pigs and the biotype and serotype and susceptibility to 16 antimicrobials was carried. Out of 853 pigs, Yersiniae were isolated from 349 pigs(40.9%). Of 349 isolates, 289 isolates(82.8%) were Yersinia enterocolitica and 54(15.5%) were Y kristensenii, 3(0.9%) were Y pesudotuberculosis and the rest 3(0.9%) were Y prederiksenii. Out of 289 isolates of Y enterocolitica, the predominants biotype was 3B comprising of 165 isolates(57.1%) and followed by biotype 2, comprising of 49 isolates(17.0%), bioptype 3A, comprising of 41 isolates(14.2%) and biotype 4 comprising of 23 isolates(8.0%). And the predominant serotype was 0 : 3 comprising of 231 isolates(79.9%) and followed by serotype 0 : 9 comprising of 42 isolates(14.5%) and 0 : 21 comprising of 10 isolates(3.5%). Y. enterocolitica were resistant to cephalothin(99%), novobiocin(99%), erythromycine(83%), ampicillin(83%) and carbenicillin(81%) and susceptible to amikacin(100%), colistin(100%), gentamicin(100%), kanamycin(100%), polymyxin B(100%), tobramycin(100%), chloramphenicol(99%), nalidixic acid(99%), neomycin(99%), streptomycin(99%) and tetracycline(99%). Most strains of biotype 2/serotype 0 : 9 were susceptible to carbenicillin(100%) and ampicillin(61%) but the other biotype/serotypes were resistant to these antibiotic.

• Food Science of Animal Resources
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• v.36 no.2
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• pp.230-236
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• 2016

Procyanidins, which are natural antioxidants and antimicrobials found in grapes, enhance the quality and extend the shelf life of meat. We explored the effects of edible films incorporating procyanidins on pork loin stored for various times. Procyanidins (0, 0.1, and 0.3%, w/w) were incorporated into the edible films. We assessed meat color, pH, levels of volatile basic nitrogen (VBN) and 2-thiobarbituric acid-reactive substances (TBARS), and microbial populations for 14 d. The chromaticities and pH values of pork loin wrapped in film containing procyanidins (0.1% and 0.3%) generally increased (p<0.05) with storage time. VBN and TBARS levels, and total bacterial and Escherichia coli (E. coli) counts, significantly decreased (p<0.05) in the procyanidin groups. In particular, procyanidins strongly inhibited TBARS formation. Thus, our findings suggest that edible film impregnated with procyanidins inhibits lipid oxidation and microbial growth, thereby enhancing the quality and shelf life of pork meat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.100-106
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• 1999

Use of chemical preservative for controlling harmful microorganisms in food products has been debated due to public concerns about food quality because of perceived toxic and carcinogenic potential. Thus, use of non toxic natural antimicrobial agents has become essential. This study was investigated to determine the antimicrobial activity of water or ethanol extract of commercially available tea, and of solvent fractionated ethanol extracts obtained from steamed green tea. Both of water and ethanol extracts of green tea(steamed or roasted), oolong tea and black tea exhibited strong antimicrobial activity against gram positive and negative bacteria, but not effective against yeast and mold. Also, antimicrobial activity of ethanol extract of 4 different kinds of tea was stronger than that of water extract. Among 4 different tea, ethanol extract of steamed green tea was further fractionated. One thousand g/disk buthanol extract had the strongest antimicrobial activity against bacteria and mold. The concentration of the antimicrobial activity of buthanol extract in tested microorganisms ranged from 125~1000 g/disk except for Rhizopus javanicus. Antimicrobial activity of buthanol extract of steamed green tea was not destroyed by heating at 100oC for 60 min and at 121oC for 15 min, which is very stable over heat treatment. The inhibitory effect of the buthanol extract on the growth of Listeria monocytogenes and Staphylococcus aureus was investigated. Growth of both strains was started in the presence of 250 and 500 g/ml after 12 and 24 hour respectively, whereas complete inactivation of both strains was occurred in the presence of 1000 g/ml.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.209-216
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• 2011

This study carried out to investigate the pathogenic Streptococcus spp. isolated from respiratory tract of Thoroughbred in Jeju province. The specimens were collected from nasal mucosa using a culture swab from 113 Thoroughbred horses. Suspected colonies were selected onto blood and MacConkey agar plate, and identified by standard biochemical properties using Vitek 2 system and PCR method. In this study, we isolated S. equi (n=6), S. zooepidemicus (n=31), S. equisimilis (n=5), S. dysgalactiae (n=2), S. agalctiae (n=1), non identified ${\beta}$-hemolytic Streptococcus spp. (n=1) from Thoroughbred horses. In antimicrobial susceptibility test, it showed a high sensibility in the most of antimicrobial except for neomycin, streptomycin, spectinomycin, erythromycin and clindamycin. These results will provide the basic information to establish control measures for the treatment and prevention of respiratory disease by pathogenic Streptococcus spp. in Thoroughbred horses in Korea.