• Parasites, Hosts and Diseases
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• 제54권1호
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• pp.15-20
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• 2016

Toxoplasmosis is an important zoonotic disease that can cause abortion in humans and animals. The aim of this study was isolation and subsequent genotyping of Toxoplasma gondii isolates in ovine aborted fetuses. During 2012-2013, 39 ovine aborted fetuses were collected from sheep flocks in Khorasan Razavi Province, Iran. The brain samples were screened for detection of the parasite DNA by nested PCR. The positive brain samples were bioassayed in Webster Swiss mice. The serum samples of mice were examined for T. gondii antibodies by IFAT at 6 weeks post inoculation, and T. gondii cysts were searched in brain tissue samples of seropositive mice. The positive samples were genotyped by using a PCR-RLFP method. Subsequently, GRA6 sequences of isolates were analyzed using a phylogenetic method. The results revealed that T. gondii DNA was detected in 54% (20/37, 95% CI 38.4-69.0%) brain samples of ovine aborted fetuses. In bioassay of mice, only 2 samples were virulent and the mice were killed at 30 days post inoculation, while the others were non-virulent to mice. The size of cysts ranged $7-22{\mu}m$. Complete genotyping data for GRA6 locus were observed in 5 of the 20 samples. PCR-RLFP results and phylogenetic analysis revealed that all of the isolated samples were closely related to type I. For the first time, we could genotype and report T. gondii isolates from ovine aborted fetuses in Khorasan Razavi Province, Iran. The results indicate that the T. gondii isolates are genetically related to type I, although most of them were non-virulent for mice.

• 미생물학회지
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• 제11권4호
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• pp.167-174
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• 1973

This study included two parts of investigation, the microfloral changes during the brewing process with the changes of pH, total acidity, temperature and alcoholic contents, as well as determination of survival times of major enteric pathogens in Takju. 1. Maximum number of Saccharomyces cerevisiae was $4.3{\times}10^7$ per milliliter on the 5th day of fermentation and gradually decreased. Saccharomyces cerevisiae was one of the predominant strains of the fermentation process. The number of Saccharomyces cerevisiae was $4.3{\times}10^6$ per milliliter at the completion of the brewing and human consumption. In a few days after the completion of the brewing. Bacillus subtilis and some species of Staphylococcus spp. began to grow and those organisms were responsible for the spoilage. 2. Maximum pH, during the brewing, was 5.8 on the first day of fermentation and rapidly decreased until 6th day of fermentation at pH 4.3. 3. Maximum alcholic content was 14.5 degree on the 4th day of fermentation, 10.3 degree on the 5th day and this degree was continued during the experimentation. 4. Maximum temperature, during Takju brewing was 34.deg.C on the 3rd day of fermentation and rapidly decreased up to 23.deg.C on the 6th day and this temperature was continued until the brewing process was finished. 5. Maximum total acidity was 0.57 percent on the 4th day of fermentation and gradually decreased by brewing process was completed. 6. Survival time of major enteric pathogenic bacteria in Takju was as follows : Shigella dysenteriae and Escherichia coli were isolated in two hours and 14 hours respectively, but Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Vibrio parahemolyticus were not isolated even in an hour after the inoculation of those organisms in undiluted Takju. In diluted Takju, Salmonella typhi, Shigella dysenteriae, and Escherichia coli were survived for 50-60 hours, but Vibrio cholerae and Vibrio parahemolyticus were not isolated even if treated within one hour.

• Journal of Microbiology and Biotechnology
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• 제21권12호
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• pp.1330-1335
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• 2011

N-Acyl homoserine lactones (AHLs) serve as the vital quorum-sensing signals that regulate the virulence of the pathogenic bacterium Erwinia carotovora. In the present study, an approach to efficiently restrain the pathogenicity of E. carotovora-induced soft rot disease is described. Bacillus thuringiensis-derived N-acyl homoserine lactonase (AiiA) was projected onto the surface of Pseudomonas putida cells, and inoculation with both strains was challenged. The previously identified N-terminal moiety of the ice nucleation protein, InaQ-N, was applied as the anchoring motif. A surface display cassette with inaQ-N/aiiA was constructed and expressed under the control of a constitutive promoter in P. putida AB92019. Surface localization of the fusion protein was confirmed by Western blot analysis, flow cytometry, and immunofluorescence microscopy. The antagonistic activity of P. putida MB116 expressing InaQ-N/AiiA toward E. carotovora ATCC25270 was evaluated by challenge inoculation in potato slices at different ratios. The results revealed a remarkable suppressing effect on E. carotovora infection. The active component was further analyzed using different cell fractions, and the cell surface-projected fusion protein was found to correspond to the suppressing effect.

• 대한수의학회지
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• 제31권4호
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• pp.479-484
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• 1991

Encephalomyocarditis(EMC) virus was isolated from the mummified and stillborn pigs at a swine farm in Chonnam Province, experienced with EMC infection over the period Oct.~Dec. of 1989. In addition some cultural, serological properties of the isolates and experimental infections in the piglets were studied. The results obtained were as follows; 1. Two EMC virus strains with HA titers and CPE similar to EMC-ATCC were established in a baby hamster kidney (BHK)-21 cell line by inoculating homogenates of brain and heart of the 19 mummified or stillborn pigs and designated $K_3$ and $K_{11}$. 2. At the second BHK-21 cell line passage of the initial isolates CPE appeared after incubation for 16~18 hours, while at the fourth and fifth passage the highest titer of HA was recorded, titer of HA using rat and guinea pig erythrocytes. 3. One pig inoculated with the isolate $K_3$ showed dyspnea as clinical signs and died at the 10 days after inoculation at necropsy white necrotic foci were observed from the dead animal heart. 4. Although all the rest surviving pigs showed increases in antibody titer and body temperature of $40^{\circ}C$ above for the initial 2~4 days followed by the return to normal, there were no gross lesions when the animals were sacrificed at the 2 weeks after inoculation.

• Mycobiology
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• 제34권2호
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• pp.67-72
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• 2006

Efficacy of resistance induction by the bacterial isolates Pseudomonas putida (TRL2-3), Micrococcus luteus (TRK2-2) and Flexibacteraceae bacterium (MRL412), which were isolated from the rhizosphere of plants growing in Jeju Mountain, were tested in a greenhouse. The disease severity caused by Phytophthora infestans was effectively reduced in the potato plants pre-inoculated with bacterial isolates compared with those of the untreated control plants growing in a greenhouse. In order to estimate the level of protection by the bacterial isolates, Mancozeb WP (Diesen $M^{(R)}$, Kyong nong) and DL-3-amino butyric acid (BABA) were pre-treated, whereas Dimethomorph WP ($Forum^{(R)}$, Kyong nong) and phosphonic acid ($H_{3}PO_{3}$) were post-treated the challenge inoculation with the pathogen. Disease severities of chemical pre-treated as well as post-treated plants were reduced compare to those of the untreated. The disease reduction in the plants pre-treated with Mancozeb WP was the highest, whereas that of post-treated with Dimethomorph WP was the lowest. The yields of plants pre-inoculated with three bacterial isolates were greatly increased than those of control plants. These results suggest that biological control by bacterial isolates might be an alternative strategy against late blight disease in potato plants growing in greenhouse.

• Applied Biological Chemistry
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• 제51권1호
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• pp.17-23
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• 2008

본 연구는 산머루를 이용한 과실주의 발효시 원료 등에서 기인한 강한 산미에 의한 과실주의 품질을 저하시키는 것을 개선시키기 위하여 혼합균주의 접종에 의한 알코올 발효 과정중 다양한 혼합배양 조건으로 감산발효를 시도하였다. 산머루 알코올 발효균주로 사용된 Saccharomyces sp. SMR-3 배양구에 Schizosaccharomyces pombe와 Schizosaccharomyces japonicus를 각각의 감산발효균주로 접종 후 혼합배양 한 결과, 산머루 알코올 발효균주 Saccharomyces sp. SMR-3에 Schizosaccharomyces pombe를 $22^{\circ}C$, 12일간 혼합 배양한 처리구가 알코올 함량 $15.8{\pm}0.2%$로 최대였고, 산도 $0.44{\pm}0.02%$, 총 유기산 함량 $648.96{\pm}7.14mg%$ , malic acid $99.30{\pm}1.24mg%$ 로 가장 낮게 나타나, 알코올 발효균주 단독으로 배양한 처리구 보다 알코올 함량은 2% 이상 높았고, 산도는 51.65%, 총 유기산은 48.02% 및 malic acid는 81.12%의 감소 효과를 나타내어 최적의 감산발효 조건으로 나타났다.

• 한국식품위생안전성학회지
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• 제35권2호
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• pp.195-204
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• 2020

식중독 미생물이 polyethylene과 stainless steel의 표면에서 biofilm을 형성하는 특성에 대하여 온도와 시간이 미치는 영향을 조사하였다. 식중독 미생물 6종(Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Salmonella Typhimurium) 32균주를 대상으로 예비실험을 하여 각 종별로 biofilm 형성능이 강한 1균주씩을 선발하였다. 시험한 식중독 미생물 6종 모두 온도가 증가함에 따라 biofilm 형성능이 증가하였으며, 식중독 미생물의 종류와 polyethylene 및 stainless steel의 표면에 따른 차이는 일관된 경향을 나타내지 않았다. E. coli와 P. aeruginosa가 polyethylene 표면에서 biofilm을 형성하는 능력은 stainless steel 표면에서 보다 유의적으로 높았다. 식중독 미생물은 표면에 균을 접종했을 때 바로 biofilm을 형성하였으며, E. coli, P. aeruginosa 및 S. Typhimurium은 접종 1시간 후에 모든 표면에서 biofilm을 형성하였다. Biofilm 형성 7일 후, S. aureus를 제외한 나머지 균주는 polyethylene과 stainless steel 표면에서 생존률에 차이가 없었다. 시험한 6종의 식중독 미생물의 경우 biofilm을 형성하는 능력은 균의 종류 및 polyethylene과 stainless steel 표면에 따라 다르게 나타났다.

• 대한환경공학회지
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• 제35권10호
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• pp.687-693
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• 2013

다양한 난개발과 해안도로, 방파제 등의 인공 구조물 설치로 인한 해안 침식과 해안선 파괴 등으로 해안사구가 크게 훼손되고 있다. 이에 본 연구에서는 해안사구에서 서식하고 있는 토착식물의 근권으로부터 식물 성장 촉진 능력이 있으면서 동시에 염분에 강한 내성을 가지는 근권세균의 library를 구축하였고, 이들 균주를 대상으로 식물 성장 촉진 능력을 평가하였다. 또한, 내염성 식물을 대상으로 사구 토양에서의 성장률에 근권세균이 미치는 영향을 평가한 후, 훼손된 사구의 복원에 가장 유용한 미생물을 선별하고 분리된 근권세균이 식물 성장에 미치는 영향을 평가하였다. 실험은 선정된 균주와 갯기름나물과 줄무늬갈대를 해안사구에 식재한 후 성장에 미치는 영향을 평가하였다. 그 결과, MH1RS1는 (IAA) production, siderophores, 1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase) 그리고 염분내성을 가지고 있다. 갯기름나물의 경우는 줄기의 길이와 뿌리의 무게는 크게 향상되었다. 특히, 줄기의 생체와 뿌리 무게는 control과 비교했을 때 25% 성장이 향상되었다. 줄무늬 갈대는 Bacillus aerius MH1RS1 에 의해 초장은 18%와 뿌리의 생체 중은 20%로 크게 향상 되었다.

• 한국식품저장유통학회지
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• 제6권4호
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• pp.448-455
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• 1999

Leuconostoc mesenteroides와 Lactobacillus brevis, Lactobacillus fermentum을 무주스에 starter로 0.3%(106 cfu/$m\ell$)첨가하여 $25^{\circ}C$에서 7일, 15$^{\circ}C$에서 20일, 5$^{\circ}C$에서 36일동안 숙성하면서 단독, 또는 혼합 배양에 의한 무주스의 가공특성을 조사하였다. 무주스를 $25^{\circ}C$에서 숙성할 경우 유산균수는 혼합배양이 단독배양보다 높게 계수 되었으나 낮은 온도 (15~5$^{\circ}C$)에서는 접종균주에 따라 증감의 차이는 있으나 starter의 첨가효과가 거의 없는 것으로 나타났다. 유산균을 접종한 경우 접종 균주에 따라 다소 차이는 있으나 비휘발성 유기산, 아스코르브산 함량이 접종하지 않은 무주스에 비해 높게 나타났다. 단독 및 혼합배양한 각각의 무주스를 가장 맛있는 상태 (적숙기)에서 차이식별검사를 실시한 결과 군덕내와 생무맛을 제외하곤 5% 수준에서 유의적 차이가 있었으며, 기호도 검사결과 Lactobacillus brevis와 Leu. mesenteroides로 $25^{\circ}C$에서 혼합 배양한 무주스가 가장 높은 점수를 얻었으며, 시중에 유통중인 동치미보다도 높은 점수를 얻어 starter 이용한 무주스의 제조는 동치미의 맛을 지니면서도 품질이 우수하여 상품성이 높을 것으로 기대된다.

• 한국토양비료학회지
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• 제21권3호
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• pp.307-315
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• 1988

근류균(根瘤菌)과 두과식물(荳科植物)과의 상호공생관계(相互共生關係)에서 발현(發現)되는 생물학적(生物學的) 질소고정(窒素固定)의 효율(效率)을 증진(增進)하기 위한 연계연구(連繫硏究)로 전보(前報)에 이어 콩 품종(品種), 질소기종(窒素期種) 및 시용량(施用量)을 달리한 in situ 숙건에서 대두근류균(大豆根瘤菌)과 협생(協生) 질소고정균(窒素固定菌)와의 상호접종효과(相互接種效果)를 질소고정효율면(窒素固定效率面)에서 검토(檢討)한 결과(結果)는 다음과 같다. 1. 콩 건물수량(乾物收量)은 H-25 및 단엽(短葉)콩 모두 근류균(根瘤菌)과 무접종(無接種)보다 근류균(根瘤菌) 단독(單獨) 및 근류균(根瘤菌)과 협생균(協生菌)과의 혼합접종(混合接種)으로 유의(有意)한 증가효과(增加效果)를 보았으나, 각(各) 균주(菌株)의 접종매체간(接種媒體間)에는 유의(有意)한 차(差)가 없었다. 또한 질소비종(窒素肥種) 및 시용량간(施用量間) 콩 건물수량(乾物收量)은 유안(硫安)보다 질산가리시용(窒酸加里施用)이 유의(有意)한 증가(增加)를 보였으며 질소시용량(窒素施用量) 증가(增加)에 따라 감소(減少)하는 경향(傾向)이었다. 2. 접종(接種) 매체량간(媒體量間) 질소고정력(窒素固定力)은 H-25 품종(品種)에서는 현저(顯著)한 차이(差異)가 없었으나, 단엽(短葉)콩에서는 근류균(根瘤菌)과 협생질소고정균(協生窒素固定菌)과의 혼합접종(混合接種)보다 근류균(根瘤菌) 단독접종시(單獨接種時) 증가(增加)되는 경향(傾向)이었다. 3. 콩 건물수량(乾物收量)과 질소고정관련(窒素固定關聯) 각(各) 요인간(要因間) 상호관계(相互關係)에서 근류형성량(根瘤形成量) 및 TNA(total nitrogenase activity)는 고도(高度)의 유의(有意)한 정(正)의 상관관계(相關關係)를 보였다. 4. 공생(共生) 질소고정효과(窒素固定效果)를 보면, H-25 품종(品種)은 84 AS-1의 근류균(根瘤菌)을 단독접종(單獨接種)하고 유안(硫安)을 54mM시용시(施用時) 149 %로 제일 높았으나 단엽(短葉)콩은 84DY-1를 단독접종(單獨接種)하고 질소가리(窒素加里)를 18mM시용시(施用時) 질소고정효과(窒素固定效果)가 155%로 제일 높았다.