• 미생물학회지
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• 제27권3호
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• pp.272-278
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• 1989

The bacteria utilizing 3-chlorobenzoate as a sole carbon and energy source were isolated by Most-Probable-Number technique and identified in Korean coastal waters. Pseudomonas, Moraxella and Flavobacterium were dominant genera and comprised 70.2% of total isolates. Forty-four biochemical, cultural, morphological and physiological testa were performed and average linding cluster analysis was conducted from the test results. Total 92.7% of isolates were clustered into 17 groups under the 80% similarity level. The degradation of 3-chlorobenzoate was performed by many heterogeneous bacteria and the species diversity of these bacterial group offers informations of the stability of bacterial communities in relation to carbon compound cycling in coastal enviromnents.

• 식물병연구
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• 제28권2호
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• pp.69-81
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• 2022

본 연구에서는 수박에서 과실썩음병을 유발하는 Acidovorax citrulli를 억제하는 세균을 선발하고, 선발한 세균이 성장촉진 및 길항 효소를 생성하는지 확인하였다. 전국 26개 지역의 94곳의 수박재배지와 25곳의 대형 원예 육묘장에서 수박 식물체(잎, 꽃, 뿌리) 및 토양을 수집하였다. 수집한 sample에서 tryptic soy agar와 yeast extract peptone dextrose 배지에서 각각 1,953종과 841종 총 2,794종의 미생물을 분리하였으며, 2,794종의 미생물 중 2종의 A. citrulli를 선발하였다. 선발한 A. citrulli에 대한 기내 길항성 검정 결과 3-3B에서 24종, 9-4B에서 14종 총 28종의 길항 세균을 선발하였다. 선발한 길항 세균 중 BNPL-6-3B, HYGPL-1-3B, TIPL-6-1B, YGMP-2-7Y는 2종의 bacterial fruit blotch균 모두에서 강한 길항성을 보였다. 선발한 28종의 길항 세균을 대상으로 총 6가지의 생화학적 검증을 진행하였으며, 선발한 길항 세균 중 CB20R-2-5B, TIPL-4-2B, TIPL-6-1B, TIPL-7-4B 4가지 균주가 5가지의 생화학적 검증에서 성장촉진 및 길항 효소를 분비하는 것을 확인하였다. 또한, BNPL-3-3B와 BNPL-6-3B 두 균주는 성장촉진 효소 분비를 확인하는 4가지의 생화학적 검증(ammonia production, phosphate solubilization, starch hydrolysis, siderophore production)에서 모두에서 효소를 분비하는 것으로 확인되었다. 본 연구에서 선발한 28종의 길항 세균은 배지에서 A. citrulli를 효과적으로 억제하였으며, 사이안화 수소와 단백질분해효소 생산 능력 검정을 통해 길항 활성을 확인하였다. 또한, 선발한 길항 세균의 암모니아 생산 및 불용성 인산 가용화 능력을 확인하여 식물 성장촉진 활성을 가지는 것으로 확인하였다. 따라서, 본 연구결과는 향후 수박 과실썩음병 방제제 및 성장촉진제 등의 친환경 농자재 개발에 유용한 기초 자료가 될 것으로 판단된다.

• The Plant Pathology Journal
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• 제30권3호
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• pp.299-303
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• 2014

This study aims to isolate and identify the causal pathogen of tomato bacterial wilt in Egypt. In 2008, tomato plants showing typical symptoms of bacterial wilt disease with no foliar yellowing were observed in Minia, Assiut and Sohag governorates, Egypt. When cut stems of symptomatic plants were submerged in water, whitish ooze was evident and longitudinal sections showed a brown discoloration in the vascular tissues. Bacteria were isolated on triphenyl tetrazolium chloride medium and fifteen isolates shown typical morphological and cultural characteristics were confirmed as Ralstonia solanacearum biovar 2 race 1. Pathogenicity tests showed that all isolates proved to be pathogenic to tomato plants, varied from 52 to 97% wilting. This is the first report of R. solanacearum biovar 2 race 1 causing bacterial wilt in tomato crop in Egypt.

• Journal of Microbiology
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• 제40권2호
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• pp.104-108
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• 2002

The hazelnut leaf holer (Anoplus roboris Sufr,, Coleoptera: Curculionidae) is a devastating pest of hazelnut and oak trees. It causes approximately 20-30% economic damage to hazelnut production per year in Turkey. In the present study, in order to fond a more effective and safe biological control agent against A. roboris, we investigated the bacterial flora of the hazelnut leave holer, and tested them for insecticidal effects on it. According to morphological, physiological and biochemical tests bacterial flora were identified as Bacillus circulans (Ar1), Bacillus polymyxa (Ar2), Enterobacter sp. (Ar3) and Bacillus sphaelicus (Ar4). Insecticidal effects of bacterial isolates were performed on adult A. roboris. The highest insecticidal effect determined was 67% by B. sphaericus within eight days. The insecticidal effects of the other isolates (Ar1, Ar2 and Ar3) were determined as 33%, 47% and 47% within the same period, respectively.

• 한국응용곤충학회지
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• 제11권1호
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• pp.5-9
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• 1972

가지과 작물의 풋마름병의 병원균(Pseudomonas solanacearum)의 생리적 성질을 구명하고자 시험한 결과는 다음과 같았다. 1, 공시균주로는 가지과작물인 도마도(7), 가지(3), 고추(6),에서 분리한 16균주를 공시하였다. 2. 탄소원에 따른 분해에서는 Glactose는 16균주가 전부 이용하였으나 Saccharose, Lactose, Starch는 이용하지 못하였으며 이외의 탄소원에서는 균주에 따라 이용 반응이 각기 틀렸다. 3. 균주에 의한 탄소원의 산도변화에서는 Glucose, Saccharose, Raffinose, Starch는 산성을 나타냈으나 Galactose, Salicin, Lactose, Dextrin, Mannitol, Esculin은 알카리성 반응을 나타내었다. 4. 생리적성질에서는 Gelatin 반응에서 균주에 따라 용해정도의 차가 나타났으며, methylene blue에서는 환원균주토 있었음을 알게 되었고, 이외의 반응에서는 같은 성질을 보여주었다.

• 산업식품공학
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• 제21권1호
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• pp.88-92
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• 2017

동해안의 특산 수산발효식품 중 가자미밥 식해, 오징어 젓갈, 지누아리 무침 등 총 3종의 수산발효식품에서 233개의 균을 분리하였다. 5종의 주요 식중독 균에 대한 항균활성을 측정한 결과 총 분리균 중 36개(15.5%)가 B. cereus ATCC 14579에 대해 항균활성을 나타내 가장 많은 분리균이 이 지시균을 저해하였다. 그 다음으로 S. aureus KCTC 1916, L. monocytogenes ATCC 15313 순으로 다수의 분리균이 항균활성을 나타냈다. 특히 오징어 젓갈에서 분리한 균주 중 각각 5개(6.0%), 3개(3.6%)가 그람음성 지시균인 E. coli O157:H7 ATCC 43895, Sal. enterica ATCC 4931를 저해하였다. 단백질 가수분해 활성의 경우, 72시간 배양 후, 총 분리균주 중 72개(30.9%)가 활성을 나타냈고, 가장 많은 활성을 나타낸 것은 지누아리 무침 분리균으로 72시간 배양하였을 때 36개(60.0%)가 단백질 가수분해활성을 나타냈다. 본 연구를 통해 수산발효식품에서 분리한 균주가 식중독균을 저해하는 항균물질을 생산한다는 것과 단백질 가수분해 능력을 가진 균주가 존재한다는 것을 알 수 있었다. 활성이 우수한 균주의 확보를 통해 우수 활성균주로부터 천연 항균제를 분리, 적용할 수 있고, 단백질 가수분해활성을 다양한 발효식품 및 더 나아가 저염 수산 발효식품 생산에 활용할 수 있을 것으로 기대된다.

• 한국임상수의학회지
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• 제21권2호
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• pp.133-139
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• 2004

Bacterial pathogens were isolated from 36 dogs with respiratory signs, that were submitted to Veterinary Clinics in Jeju, including Veterinary Medical Teaching Hospital in Cheju National University. Of 36 isolates, 16 (44.4%) bacterial pathogens were Gram-positive and 20 (55.6%) were Gram-negative. Gram-positive bacteria identified with API Staph were 12 S. intermedius (33.3%), 2 S. aureus (5.6%), 1 S. haemolyticum (2.8%), and 1 S. xylosus (2.8%). Gram-negative organisms identified with API 20E or API NE included 8 Bordetella bronchiseptica (22.2%), 6 Escherichia coli (16.7%), 4 Pasteurella spp. (11.1%), 1 Enterobacter intermedius (2.8%), and 1 Oligella ureolytica (2.8%). Both Staphylococcus spp. isolates and Gram-negative pathogens were resistant to one or more antibiotics, including ampicillin (AM), amoxicillin/clavulanic acid (AMC), chloramphenicol (C), cefazolin (CZ), erythromycin (E), gentamicin (GM), kanamycin (K), lincomycin (L), oxacillin (OX), trimethoprim/sulfamethoxazole (SXT), and tetracycline (TE). All Staphylococcus spp. were susceptible to AMC, OX and VA, while many isolates were highly resistant to L (87.5%), E (68.8%), P (62.5%), and AM (56.3%). Antibiotic-resistant patterns of staphylococcal isolates were shown ranges from single to 9-resistant patterns. Resistant rates to antibiotics of Gram-negative bacteria were usually higher than those of Staphylococcus spp. in this study. Most Gram-negative bacteria were highly resistant to L (90.0%), AM (85.0%), E (85.0%), P (85.0%), OX (80.0%), and CZ (75.0%). B. bronchiseptica isolates showed 5 to 8 antibiotics-resistant patterns and Pasteurella spp., 2 to 8-resistant patterns. In particular, all 6 E. coli isolates were resistant to more than 9 different kinds of antibiotics, including one strain resistant to all antibiotics tested.

• Journal of Microbiology and Biotechnology
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• 제20권1호
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• pp.169-178
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• 2010

The microbial community structure in Thailand soils contaminated with low and high levels of arsenic was determined by denaturing gradient gel electrophoresis. Band pattern analysis indicated that the bacterial community was not significantly different in the two soils. Phylogenetic analysis obtained by excising and sequencing six bands indicated that the soils were dominated by Arthrobacter koreensis and $\beta$-Proteobacteria. Two hundred and sixty-two bacterial isolates were obtained from arsenic-contaminated soils. The majority of the As-resistant isolates were Gramnegative bacteria. MIC studies indicated that all of the tested bacteria had greater resistance to arsenate than arsenite. Some strains were capable of growing in medium containing up to 1,500 mg/l arsenite and arsenate. Correlations analysis of resistance patterns of arsenite resistance indicated that the isolated bacteria could be categorized into 13 groups, with a maximum similarity value of 100%. All strains were also evaluated for resistance to eight antibiotics. The antibiotic resistance patterns divided the strains into 100 unique groups, indicating that the strains were very diverse. Isolates from each antibiotic resistance group were characterized in more detail by using the repetitive extragenic palindromic-PCR (rep-PCR) DNA fingerprinting technique with ERIC primers. The PCR products were analyzed by agarose gel electrophoresis. The genetic relatedness of 100 bacterial fingerprints, determined by using the Pearson product-moment similarity coefficient, showed that the isolates could be divided into four clusters, with similarity values ranging from 5-99%. Although many isolates were genetically diverse, others were clonal in nature. Additionally, the arsenic-resistant isolates were examined for the presence of arsenic resistance (ars) genes by using PCR, and 30% of the isolates were found to carry an arsenate reductase encoded by the arsC gene.

• 한국균학회지
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• 제23권2호통권73호
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• pp.190-195
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• 1995

고추탄저병(Colletotrichum gloeosporioides)에 대한 생물학적방제 능력을 가지는 엽권미생물을 선발하기 위하여 38과 87종의 약용식물로부터 243균주의 세균과 51균주의 사상균 그리고 30균주의 효모를 분리하여 이들에 대하여 항진균활성검정을 in vitro 및 in vivo에서 실시한 결과는 다음과 같다. 분리된 엽권미생물 중에서 PDA 배지 대치배양에서 10 mm 이상의 생육저지대를 형성하는 4개의 엽권미생물이 선발되었다. 선발된 4개의 세균균주 KB6, KB12, KB13 및 KB14의 PDB 배양여액 중에서 KB12 균주가 균사생장 억제율이 가장 높았다. 액체배양여액 처리에서 푸른 고추보다 붉은 고추에서 방제효과가 컸다. Bacterial cell 처리에서는 푸른 고추나 붉은 고추에서도 높은 방제효과가 있었다. 선발된 4개의 세균균주들은 모두 Bacillus subtilis로 동정되었다.

• The Plant Pathology Journal
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• 제20권3호
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• pp.172-176
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• 2004

Bacterial isolates TRL2-3 and TRK2-2 showing anti-fungal activity in vitro test against some plant pathogens were identified as Pseudomonas putida and Micrococcus luteus, respectively. Pre-treatment with both bacterial isolates at the concentration 1.0$\times$ $10^7$ and $10^6$cfu/ml in the rhizosphere could trigger induced systemic resistance in the aerial part of cucumber plants against anthracnose caused by Colletotrichum orbiculare. However, the pre-treatment with the higher concentration at 1.0 $\times$ $10^8$ cfu/ml of both isolates could not induce resistance after challenge inoculation with C. orbiculare. As a positive control, the treatment with DL-3 amino butyric acid caused a remarkable reduction of disease severity whereas the lesions on the leaves of untreated plants developed apparently after the fungal inoculation. From these results, it was recomended that disease control using both bacterial isolates inducing systemic resistance in the field where chemical application is forbid.