• Mycobiology
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• 제42권3호
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• pp.269-273
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• 2014

During 2010 and 2012 grape harvest seasons in Gyeonggi-do, Korea, a white stain symptom was observed on the harvested grape fruits in 'Campbell-Early' and 'Kyoho' varieties. In samples collected from the infected vine, two different strains of pathogenic fungi have been found and identified as Acremonium acutatum and Trichothecium roseum based on fungal morphology and nucleotide sequence of internal transcribed spacer (ITS) and supported by the phylogenetic analysis of the rDNA-ITS region. The DNA homologies of the isolated strains were 99.8% and 99.6% identical with T. roseum (IFB-22133) and A. acutatum (CBS682.71), respectively. In the pathogenicity test, the spores of A. acutatum and T. roseum sprayed on the grapes caused white stain symptoms on the fruits in two weeks after the artificial inoculation, which is similar to observations in the field. To our knowledge, this is the first report of white stain symptoms caused by A. acutatum and T. roseum on the grapes in Korea.

• Journal of Microbiology and Biotechnology
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• 제19권8호
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• pp.792-802
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• 2009

Antimicrobial peptides (AMPs) are considered to be a promising alternative to conventional antibiotics for future generations. We identified four novel hexapeptides with antimicrobial activity: KCM11 (TWWRWW-$NH_2$), KCM12 (KWRWlW-$NH_2$), KCM21 (KWWWRW-$NH_2$), and KRS22 (WRWFIH-$NH_2$), through positional scanning of a synthetic peptide combinatorial library (PS-SCL). The ability of these peptides to inhibit the growth of a variety of bacteria and unicellular fungi was evaluated. KCM11 and KRS22 preferentially inhibited the normal growth of fungal strains, whereas KCM12 and KCM21 were more active against bacterial strains. Bactericidal activity was addressed in a clear zone assay against phytopathogenic bacteria, including Pectobacterium spp., Xanthomonas spp., Pseudomonas spp., etc. KCM21 showed the highest activity and was effective against a wide range of target organisms. Application of KCM21 with inoculation of Pectobacterium carotovorum subsp. carotovorum on detached cabbage leaves resulted in an immune phenotype or a significant reduction in symptom development, depending on the peptide concentration. Cytotoxicity of the four hexapeptides was evaluated in mouse and human epithelial cell lines using an MTT test. The results revealed a lack of cytotoxic effects.

• Journal of Microbiology
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• 제35권2호
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• pp.117-122
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• 1997

Several dominant 4-CPA-degrading bacteria were isoalted from agricultural soils. Most of the isolates were identified as Burkholderia species by fatty acid methyl ester (FAME) analysis, but they were idstinct in chromosomal patterns obtained by PCR amplification of repetitive extragenic palindromic (REP) sequences. These strains were generally restricted in their substrate utilization capabilities. The 4-CPA degradative enzymes were idnducible by 4-CPA and some isolates appeared to mineralize 4-CPA via formation of 4-chlorophenol and 4-chlorocatechol as intermediates during its biodegradation pathway. Plasmid DNAs were not detected from most of the isoaltes and their 4-CPA genes wer on the chromosomal DAN. The 4-CPA degradation patterns in axenic cultures and natural soils varied depending on the strains and soils. The inoculation of 4-CPA degraders much improved the removal of 4-CPA from the 4-CPA treated soils.

• The Plant Pathology Journal
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• 제15권3호
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• pp.168-171
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• 1999

Crude extracts of pathogenic Streptomyces turgidiscabies isolates produced necrotic reaction on potato slices. Necrosis was first visible 24 hr after application and increased in severity over several days. However, necrosis was not observed when crude extracts of nonpathogenic strains were applied onto tuber slices. Presence of thaxtomin A from crude extracts of pathogenic S. turgidiscabies was identified by thin layer chromatography and high performance liquid chromatography. Nonpathgenic strains did not produce thaxtomin A in oatmeal broth. Inoculation of potato tuber slices with thaxtomin A partially purified from crude extract of a pathogenic S. turgidiscabies ST5 reproduce necrotic reaction suggesting that thaxtomin A is a pathogenicity determinant in S. turgidiscabies.

• 대한수의학회지
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• 제33권3호
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• pp.419-427
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• 1993

Thirteen strains of Clostridium perfringens were isolated from the pigs with hemorrhagic enteritis. The characteristics of the outbreaks, clinical signs and lesions were examined. The biochemical properties, type of toxin and susceptibility to antimicrobial agents of the isolates were investigated. The results could be summarized as follows ; 1. Almost of the pigs affected with hemorrhagic enteritis, 17 cases examined from 1989 to 1992, were piglets less than 7 day old. 2. The average mortality rate of piglet less than 7 day old affected with hemorragic and necrotic enteritis was 48.5%. 3. The clinical signs of pigs with hemorrhagic enteritis were depression, hemorrhagic diarrhea, anemia and dehydration. Necropsy of the infected pigs showed typical hemorrhage of upper intestine and necrosis of mucosal membrane. 4. The characteristic biochemical properties of the isolates were 2-band hemolysis, positive reaction of reverse CAMP test and formation of LV precipitate in egg yolk medium. 5. The toxin type of the 13 isolates, investigated by mouse inoculation test, was all type C strains of Clostridium perfringens. 6. In susceptibility test to antimicrobial agents, 13 isolates of Clostridium perfringens were highly sensitive to ampicillin, enrofloxacin(Baytril), cephalothin, penicillin and trimethoprim-sulfamethoxazole.

• 한국어병학회지
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• 제21권3호
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• pp.209-217
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• 2008

A disease with mass mortality characterized exophthalmia and abdominal distension by ascites occurred in farmed starry flounder, Platichthys stellatus in Pohang since October of 2007. Severe necrosis and infiltration of inflammatory cells were observed in tissue histopathological sections from liver, kidney, spleen and heart of the diseased fish. The catalase-negative and gram positive cocci with -hemolysis were isolated from moribund fish. Analysis of the API profiles and the multiplex PCR of the isolates showed that strains were identified as Streptococcus parauberis. In API profiles, S. parauberis isolated from starry flounder differed from those of olive flounder, Paralichthys olivaceus to the test of arginine dihydrolase, D-mannitol, D-sorbitol and α-lactose. And the strains, PH0710 and PH0711, were strongly lethal for starry flounder (LD50 ranging from 4.2×103~4.2×102 cfu/fish at 7 days after intraperitoneally inoculation). This is the first report on a S. parauberis infection in starry flounder.

• 한국균학회지
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• 제49권4호
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• pp.441-454
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• 2021

Fungal diseases including anthracnose, stem rot, blight, wilting, and root rot of crops are caused by phytopathogens such as Colletotrichum species, Sclerotinia sclerotiorum, Phytophthora species, and Fusarium oxysporum and F. solani which threaten the production of chili pepper. In this study, to identify biological control agents (BCAs) of phytopathogenic fungi, potentially useful Bacillus species were isolated from the field soils. We screened out five Bacillus strains with antagonistic capacity that are efficiently inhibiting the growth of phytopathogenic fungi. Bacillus species were characterized by the production of extracellular enzymes, siderophores, and indole-3-acetic acid (IAA). Furthermore, the influence of bacterial strains on the plant growth promoting activity and seedling vigor index were assessed using Brassica juncea as a model plant. Inoculation with Bacillus subtilis SRCM 121379 significantly increased the length of B. juncea shoots and roots by 45.6% and 52.0%, respectively. Among the bacterial isolates, Bacillus subtilis SRCM 121379 showed the superior enzyme activities, antagonistic capacity and plant growth promoting effects. Based on the experimental results, Bacillus subtilis SRCM 121379 (GenBank accession no. NR027552) was finally selected as a BCA candidate.

• 대한방사선기술학회지:방사선기술과학
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• 제44권3호
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• pp.231-237
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• 2021

The ongoing coronavirus disease 2019 (COVID-19) pandemic has highlighted the importance of hospital hygiene and infection control in hospital settings. To raise hygiene awareness among ultrasound technicians, we evaluated the hygiene status of an ultrasound room, in comparison with that of objects used in daily life. Using the swab method, the following surfaces were examined: eight surfaces in the ultrasound room including the ultrasound probes (convex, linear, sector, 3D), ultrasound track ball, ultrasound keyboard, ultrasound gel (sealed and in use) and pillow as well as four surfaces of everyday objects including subway handles, common computer keyboards, common computer mouse, and cell phones. The streak plate technique was used for inoculation into media, which was observed for the formation of bacterial colonies following incubation for 24 h. Six bacterial strains were detected from objects used in the ultrasound room, including methicillin-resistant Staphylococcus aureus. Four strains of bacteria were detected on surfaces of everyday objects. The equipment and accessories used in an ultrasound room can act as vehicles for infecting patients. Establishment of standardized hygiene protocols and periodic training of the staff are recommended to avoid cross-infection.

• 식물병연구
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• 제17권3호
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• pp.302-310
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• 2011

Elsinoe fawcettii는 현재 감귤 산업의 경제 가치를 떨어뜨리며, 감귤 더뎅이병을 일으키는 원인중 하나로 일반적으로 살균제를 이용하여 방제가 이루어지고 있다. 하지만 안전한 농산물에 대한 관심이 증대되면서 생물학적인 방제에 대한 연구가 많이 요구되고 있다. 이에 미생물 방제에 대한 연구로서 제주에서 분리한 식물근권세균 215개 중 Elsinoe fawcettii에 의해 발병되는 감귤 더뎅이병균의 항균 효과와 병원균 발병 억제효과가 나타나는지 조사하였다. 그 중 in vitro 실험에서 더뎅이병균에 저지원을 형성하며 항균 효과를 나타내는 근권세균은 THJ 609-3, MRL 408-3, TRH 423-3이었다. 또한 이들 식물근권세균을 선처리하고 병원균을 접종한 결과 감귤 더뎅이병 억제효과가 있었다. 근권세균에 의한 병억제 기작을 알아보기 위해 형광현미경을 이용하여 조사한 결과 선발된 식물근권 세균이 병원균의 포자수를 감소시켰으며 병원균 발아율도 접종 1일 후에 감소되었다. 식물근권세균 rDNA의 Internal Transcript Spaces(ITS)을 분석을 통해 동정한 결과 THJ 609-3은 Pseudomonas pudia로 동정되었으며, MRL 408-3과 TRH 423-3은 Burkholderia gladioli로 동정되었다. 본 연구는 생물적 방제로 감귤 더뎅이병균을 방제할 수 있는 친환경적 미생물제제로 유용하게 이용할 수 있는 가치가 있다고 생각된다.

• 한국토양비료학회지
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• 제34권3호
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• pp.185-191
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• 2001

호남지역 농경지에 수년간 사용되어 온 타로닐, 만코지, 벤타존 및 부타클로르약제에 대한 내성균의 밀도를 조사하고 이들 내성균주를 분리하여 미생물속의 분포 및 타로닐의 분해정도를 검토한 결과는 다음과 같다. 호남지역 농경지에 분포한 타로닐을 비롯한 4개약제 $500{\mu}g\;ml^{-1}$에 생존하는 내성균의 밀도는 $10^3cfu\;g^{-1}$이 상으로 시설재배지> 밭> 논토양 순으로 높았고, 약제별로는 벤타존> 부타클로르> 타로닐> 만코지 순으로 높았으며, 이들4개 약제 $500{\mu}g\;ml^{-1}$에서 분리된 내성균주의균속 분포율은 Acinetobacter속과 Corynebacterium속이 높게 나타났으나 Moraxella속은 낮게 나타났다. 타로닐 연용 밭토양에 $0{\sim}100{\mu}g\;g^{-1}$까지 처리후 20일간 배양시 사상균수는 초기보다 감소하였으나 호기성3, 방선균 및 타로닐내성균수는 크게 증가하였고, 멸균 토양중에서 다코닐약제 분해균주의 밀도는 $10{\mu}g\;g^{-1}$처리시 접종후 5일경에 가장 높았고, TD-25균주는 TC-23균주보다 높은 밀도로 나타났다. 다코닐 약제처리후 20일째의 약제잔류농도는 고농도처리에서 높았고 약제분해는 TD-25균주> 무멸균토양 함유균주> TC-23균주 순으로 나타났다.