• Research in Plant Disease
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• v.15 no.2
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• pp.130-133
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• 2009

We have conducted in vitro experiments with nano-silver liquid for their effect against various plant pathogenic bacteria. Different types of nano-silver liquid WA-CV-WA13B, WA-AT-WB13R and WA-PR-WB13R were used. These are classified based on different manufacturing processes. The tested bacteria were provided by KACC. We experimented ten bacterial isolates in Clavibacter, Erwinia, Pseudomonas, Ralstonia, and Xanthomonas genera. In order to determine the level of concentrations of control effects, different concentrations (10, 25, 50, and 100 ppm) of each different nano-silver liquid were added in the culture media. As a result, WA-CV-WA13B showed high inhibition effect against C-1 at 10 ppm, and showed minor inhibition effects against P-6, X-1, and X-2. WA-AT-WB13R showed bactericidal effect against P-6 at 10 ppm. At 10 ppm, WA-AT-WB13R showed relatively high inhibition effects against C-1, X-1, and X-2. WA-PR-WB13R showed bactericidal effects against P-5, P-6 and X-2 at 10 ppm or higher concentrations. All the tested three nano-silver liquid showed bactericidal effects against all the tested plant pathogenic bacteria at concentrations of 25 ppm or higher. These results indicated the possible use of nano-silver liquid for the control of plant pathogenic bacteria.

• Journal of Veterinary Clinics
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• v.14 no.2
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• pp.349-351
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• 1997

7세의 홀스타인 암소에서 엽록소가 없는 Prototheca에 의한 만성적인 진행성 유방 염의 발생에 대해 보고한다. 유방염 우유로 만든 습윤표본에서 명확한 세포벽과 내생포자를 갖고 있는 구형 내지 난원형의 병원체가 직접 관찰되었고, Sabouraud배지에서의 순수배양물 에 대해 Wright염색 및 PHOL염색을 했을 때 algae가 증명되었으며, nutrient배지에서 세균 이 중식하지 않아서 Prototheca가 유방염의 원인으로 제시되었다. 이 병원체는 자연상태에서 는 사물기생성이지만 감염원은 확실하지 않았다. algae와 진균의 형태학적인 연구를 하는데 있어서 PHOL염색액을 광범위하게 응용할 수 있음을 제시하였다. Prototheca의 ecology와 병원성을 규명하기 위해 더 많은 연구가 이루어져야 될 것으로 생각된다.

• Korean Journal of Microbiology
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• v.39 no.1
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• pp.56-61
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• 2003

The purpose of the present study was to screen the effective of lactic acid bacteria (LAB), as probiotics which are able to protect bacterial fish diseases and investigate their characteristics. Twenty strains of lactic acid bacteria were isolated from fish intestine. fermented fish foods and kimchis. These bacteria were screened for antagonistic activity against fish pathogenic bacteria. Seven tested LAB strains were able to inhibit the fish pathogenic bacteria, including Vibrio anguillarum, Edwardsiella tarda and Streptococcus sp. Of the probiotic candidates, BK19 strain which from fermented pollack viscera indicated the largest inhibition activity. This particular probiotic bacteria was identified and named as Lactobacillus sakei BK19. In the scanning electron microscope observation, L. sakei BK19 supernatant treated V.anguillarum cell wall had been destroyed incubate after 3 hr.

• The Korean Journal of Mycology
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• v.26 no.1 s.84
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• pp.60-68
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• 1998

The effect of P. agarici and P. tolaasii causing the bacterial disease of mushrooms on the mycelial growth and fruitbody formation of F. velutipes was evaluated in laboratory. When the pathogenic bacteria was inoculated simultaneously with F. velutipes or 5 days after inoculation of F. velutipes, they significantly deterred both mycelial growth and fruitbody formation of F. velutipes in sawdust culture and showed strong inhibition under high population density. They appeared to be tender or milky in exhibiting symptom on F. velutipes by inoculating the concentration of $10^2{\sim}10^6$ of unit/g media, and their growth seemed to be stopped under $10^8\;cfu/g$ media. On $10^2\;cfu/g$ media of P. agarici and $10^4\;cfu/g$ media of P. tolaasii, there was no effect on the fruitbody yield of F. velutipes. P. tolaasii was more suppressive in the mycelial growth of F. velutipes than P. agarici, while on fruitbodies formation of F. velutipes, P. agarici showed slightly higher inhibition than that of P. tolaasii. When the bacteria was inoculated 10 days after inoculation of F. velutipes, both mycelial growth and fruit body formation were not affected nearly.

• Journal of agricultural medicine and community health
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• v.30 no.2
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• pp.137-149
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• 2005

Objectives and Methods: This study was performed to investigate the etiologic bacterial, viral and protozoal organisms for the diarrhea from hospitals in Chungnam area from January to December in 2004. Total of 787 fecal samples were collected and examined. Results and Conclusions: In test for enteropathogenic bacteria, total of 79 cases out of 787 samples from hospitals showed positive isolation. Among 79 positive samples, 27 cases were confirmed as Salmonella spp.. 20 cases as pathogenic E. coli, 18 cases as Clostridium perfringens, 6 cases as Staphylococcus aureus, 4 cases as Shigella spp. and 4 cases as Vibrio parahaemolyticus. In test for enteropathogenic virus, 190 cases out of 787 samples from hospitals showed positive reaction. Among 190 samples, 115 cases were confirmed as rotavirus, 55 cases as norovirus, 5 case as astrovirus, 4 case as rotavirus & norovirus, 3 cases as adenovirus, 2 case as rotavirus & astrovirus. In test for enteropathogenic protozoa, 6 cases out of 787 samples from hospitals showed positive result. Among 6 samples, 5 cases were confirmed as Entamoeba histolytica and 1 cases as Giardia lamblia. When we classified the positive results by the age of the patients, the highest isolation rate was noted in a group of age under 10 and over 60 for bacterial, viral and protozoal pathogens. Especially, patient below age of 5 showed high positive rate. When we classified the positive results by the time, pageathogenic bacteria were isolated throughout the year, and the highest frequency was noted in August. On the other hand, pathogenic viruses were detected more frequently during the colder season from December to April. Antimicrobial susceptibility test for the isolated bacteria resulted as follows; Salmonella strains showed high drug resistance rates against ampicillin, chloramphenicol, tetracycline, nalidixic acid, ticarcillin. Shigella strains showed high drug resistance rates against ampicillin, trimethoprim/sulfamethoxazole, chloramphenicol, tetracycline, ampicillin/sulbactam, ticarcillin. Pathogenic E. coli strains showed high drug resistance rates against ampicillin, cephalothin, gentamicin, tetracycline, nalidixic acid, ampicillin/sulbactam, ticarcillin.

• Korean Journal of Veterinary Service
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• v.46 no.1
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• pp.35-45
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• 2023

Pathogenic Escherichia coli is the cause of a wide range of diseases in pigs, including diarrhea, edema disease, and septicemia. Diarrhea caused E. coli may result in significant economic losses, making pathogenic E. coli an important pathogen for the swine industry. This study investigated the prevalence of virulence factor genes, antimicrobial resistance phenotypes, and resistance genes in E. coli isolated from feces of piglets in Korea between 2017 and 2020. As a result, 119 pathogenic E. coli isolates were obtained from 601 fecal samples. The F4 adhesin gene and the STb enterotoxin gene were commonly present in E. coli isolated from diarrhea samples. The dominant virulotypes of isolates from diarrhea samples were STb, Stx2e, and F4:LT:STb. More than 80% of the screened isolates were resistant to ampicillin, sulfisoxazole, chloramphenicol, or tetracycline. To confirm the resistance mechanisms for β-lactam or quinolone, we investigated the genotypic factors of resistance. Each of the ceftiofur-resistant E. coli produced an extended-spectrum β-lactamase encoded by bla_CTX-M-14, bla_CTX-M-27, and bla_CTX-M-55. And all ciprofloxacin-resistant E. coli harbored mutations in quinoloneresistance-determining-regions. In addition, some of the ciprofloxacin-resistant E. coli contained the plasmid-mediated-quinolone-resistance genes such as qepA, qnrB1, or qnrD. This study has confirmed that the F4 fimbria and the STb enterotoxin are the most predominant in pathogenic E. coli isolated from piglets with diarrhea in Korea and there is a great need for responsible and prudent use of antimicrobials to treat colibacillosis.

• The Korean Journal of Zoology
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• v.35 no.3
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• pp.383-394
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• 1992

비병원성 세균인 고acirlus subtilis(ATCC6633)를 등검은메뚜기(Euprepocnemis shr'rakii Bolivar)의 성충 복강에 주입한 후, 혈구의 반응양상을 투과전자현미경으로 관찰하였다. 세균에 대한 혈구의 면역반응은 plasmatocyte와 granulocyte에 의한 식 세포작용(phagocytosis)의 형태로 이루어졌으며, 결절형꽁(nodule formation)은 일어나지 않았다. 식 세포작용의 초기 반응은 혈구의 세포질 돌기가 돌출되 면서 이물질을 둘러싼 후, 원형질막과의 융합에 의해 식포가 형성되었고, 식포의 주변부에서는 일차 리소조옴의 집적이 관찰되었으며, 이런 과정은 세균 주입후, 10분 이내에 완료되었다. 일차 리소조옴은 세균 주입 후 1시간 이내에 식포의 한계막과 융합하여 이차 리소조옴을 형성하였으며, 소화된 이물질은 9시간 이내에 exocytosis에 의해 배출 되었다.

• 대한치주과학회:학술대회논문집
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• 2005.11a
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• pp.185-185
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• 2005

• The Microorganisms and Industry
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• v.35 no.1
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• pp.10-13
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• 2009

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.94.2-94
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• 1996