• 농약과학회지
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• 제13권1호
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• pp.45-53
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• 2009

KLF01으로 명명된 세균이 토마토의 뿌리에서 분리 되었고 생화학적, 유전학적 검증을 통해 Lactobacillus sp.로 동종 되었다. In vitro 실험에서 식물성 세균인 Ralstonia solanacearum를 비롯하여, Xanthomonas axonopodis pv. citri, Xanthomonas campestris pv. vesicatoria, Eriwinia pyrifoliae, Eriwinia carotovora subsp. carotovora group에게도 저해 효과를 나타내는 것으로 확인되었다. 고추와 토마토를 이용한 in vivo 실험에서는 특히 R. solanacearum에 대해 대조구와 비교 시들음병의 진행을 저해하는 것으로 관찰되었다.

• 식물병연구
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• 제25권4호
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• pp.179-187
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• 2019

이 연구는 플라즈마 기술 (radio frequency-thermal plasma system과 direct current sputtering system)을 이용하여 제작된 나노 금속복합체를 이용하여 박과 작물(수박, 호박, 박)의 종자에서 분리한 미생물의 항균 활성 효과를 검정하기 위하여 실험을 진행하였다. 8종의 나노 금속복합체와 4가지의 담체를 이용하여 5종의 곰팡이와 10종의 세균을 대상으로 기내 실험을 수행하였다. 그 결과, 곰팡이를 대상으로 한 항균실험에서 나노 금속복합체 Brass/CaCO₃의 경우 1,000 ppm 농도에서 5종의 곰팡이에 대하여 100%의 항균효과를 나타내었다. 세균을 대상으로 한 항균실험의 경우 나노 금속복합체 Brass/CaCO₃(1,000 ppm)은 Weissella sp., Rhodotorula mucilaginosa, Burkholderia sp. 그리고 Enterococcus sp. 4가지 세균을 100% 억제하는 것으로 확인되었다. 나노 금속복합체 G-Ni은 Rhizopus stolonifer에 대하여 100% 항균효과를 나타냈으며, 4가지 곰팡이에 대해서는 52.94-71.76% 정도의 항균효과를 나타내었다. 하지만 나노 금속복합체 G-Ni은 10종의 세균에 대해서는 효과가 없는 것으로 나타났다. 요약하면, 8가지 나노 금속복합체와 4가지 담체 중에서 Brass/CaCO₃가 5종의 곰팡이와 4종의 세균 대하여 항균효과가 있었으며, G-Ni는 5종의 곰팡이에 대해서 52.94-100% 효과를 보였으나 세균에 대해서는 항균효과가 없는 것으로 확인되었다.

• 수산해양교육연구
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• 제28권6호
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• pp.1828-1833
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• 2016

The purpose of this research was to investigate the bacterial flora of healthy olive flounder larvae (Paralichthys olivaceus) and live feeds (Rotifer spp. and Artemia spp.). The total bacteria counts were $9.2{\times}10^7$ and $1.2{\times}10^{10}cfu/g$ and Vibrio sp.(82.8%) was dominant in rotifers. The total bacteria counts were $3.8{\times}10^6$ and $9.2{\times}10^6cfu/g$ and Vibrio sp.(73.3%) was dominant in artemia. In olive flounder larvae, the total bacteria counts were $1.4{\times}10^6{\sim}8.3{\times}10^7cfu/g$ and V. harveyi (38.5%) was dominant. It might be potential marker of disease outbreak in olive flounder larvae.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1994년도 Proceedings of International Symposium on BIOLOGICAL CONTROL OF PLANT DISEASES Korean Society of Plant Pathology
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• pp.50-61
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• 1994

Biological control of important fungal diseases such as Phytophthora blight of red pepper, gary mold rot of vegetables, and powdery mildew of many crops was attempted using an antagonistic bacterium, Bacillus sp. AC-1 in greenhouses and fields. The antagonistic bacterium isolated from the rhizosphere soils of healthy red pepper plant was very effective in the inhibition of mycelial growth of plant pathogenic fungi in vitro including Phytophthora capsici, Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Valsa mali, Fusarium oxysporum, Pythium ultimum, Alternari mali, Helminthosporium oryzae, and Colletotrichum gloeosporioides. Culture filtrate of antagonistic Bacillus sp. AC-1 applied to pot soils infested with Phytophthora capsici suppressed the disease occurrence better than metalaxyl application did until 37 days after treatment in greenhouse tests. Treatments of the bacterial suspension on red pepper plants also reduced the incidence of Phytophthora blight in greenhouse tests. In farmers' commercial production fields, however, the controlling efficacy of the antagonistic bacteria was variable depending on field locations. Gray mold rot of chinese chives and lettuce caused by Botrytis cinerea was also controlled effectively in field tests by the application of Bacillus sp. AC-1 with control values of 79.7% and 72.8%, respectively. Spraying of the bacterial suspension inhibited development of powdery mildew of many crops such as cucumber, tobacco, melon, and rose effectively in greenhouse and field tests. The control efficacy of the bacterial suspension was almost same as that of Fenarimol used as a chemical standard. Further experiments for developing a commercial product from the antagonistic bacteria and for elucidating antagonistic mechanism against plant pathogenic fungi are in progress.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권1호
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• pp.34-44
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• 2021

Acid mine drainage (AMD) resulting from pyrite oxidation in mining areas, subsequently leads to soil acidification accompanied by lowering pH and high concentration of metals and metalloids in its surrounding environment. Regarding to this, the microbial amelioration has been considered as a promising option for a more cost-effective and eco-friendlier countermeasure, compared to the use of alkaline chemicals. This study was aimed to evaluate influencing factors in microbially-mediated amelioration of acidic soil spiked by simulated AMD. For this, microcosm experiments were conducted by acid-neutralizing bacterial consortium (dominated by Klebsiella sp. and Raoultella sp.) under the various conditions of AMD spikes (0-2,500 mg SO42-/L), together with acidic mine soil (0-100 g) or sphagnum peat (0-5 g) in the 200 mL of nutrient medium. The employed bacterial consortium, capable of resisting to high level of sulfate concentration (up to 1,500 mg SO42-/L) in low pH, generated the ammonium while concomitantly reduced the sulfate, subsequently contributing to the effective soil stabilization with an evolution of soil pH up to neutral. Furthermore, it demonstrates that suitable condition has to be tuned for successful microbial metabolism to facilitate with neutralization during practical application.

• Mycobiology
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• 제28권4호
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• pp.190-192
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• 2000

Antifungal bacteria for biological control of plant diseases or production of novel antibiotics to plant pathogens were isolated in 1997 from various soils of Ansung, Chunan, Koyang, and Paju in Korea. Sixty-four bacterial strains pre-screened from approximately 1,400 strains were tested on V-8 juice agar against eight plant pathogenic fungi using in vitro bioassay technique for inhibition of mycelial growth. Test pathogens were Alternaria mali, Colletotrichum gloeosporioides, C. orbiculare, Fusarium oxysporum f. sp. cucumerinum, F. oxysporum f. sp. lycopersici, Magnaporthe grisea, Phytophthora capsici, and Rhizoctonia solani. A wide range of antifungal activity of bacterial strains was found against the pathogenic fungi, and strain RC-B77 showed the best antifungal activity. Correlation analysis between inhibition of each fungus and mean inhibition of all eight fungi by 64 bacterial strains revealed that C. gloeosporioides would be best appropriate for detecting bacterial strains producing antibiotics with potential as biocontrol agents for plant pathogens.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.348-352
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• 2005

In this study, fermentation using a rotary biofilm contactor was conducted to improve bacterial cellulose production. We investigated the optimal fermentation conditions by using a newly isolated Gluconacetobacter sp. RKY5 in the rotary biofilm contactor. The optimal total area of discs was found to be 1,769 $cm^2$ at which bacterial cellulose and cell concentration was obtained to 5.52 g/L and 4.98 g/L, respectively. In case of aeration experiment, when the aeration rate was 1.25 vvm, the maximal bacterial cellulose (5.67 g/L) was obtained and cell concentration was 5.25 g/L.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.957-961
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• 2000

A series of experiments was conducted to evaluate phytin phosphohydrolysis actlVlty in the rumen and to isolate phytase positive rumen bacteria. Endogenous phytase activity of wheat bran was estimated and compared with that of bacterial phytin phosphohydrolysis. Substantial phytase activity was detected in wheat bran during in vitro rumen incubation. Bacterial phytase activity was suggested not to be high. Only two facultative anaerobes, Klebsiella sp. and Corynebacterium sp. were isolated as phytase producing organisms. These belonged to a minor microbial group in the rumen population. Protozoal fraction showed an initial velocity of phytin phosphohydrolysis 7 times higher than the bacterial fraction.

• Food Science and Biotechnology
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• 제16권2호
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• pp.320-324
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• 2007

The bacterial diversity in Korean soybean-fermented foods was investigated using a PCR-based approach. 16S rRNA sequences were amplified and cloned from two different soybean-fermented foods such as doenjang (soybean paste), and ganjang (soybean sauce). Staphylococcus equorum (60.6%), Tetragenococcus halophila (21.2%), Leuconostoc mesenteroides (9.1%), Lactobacillus sakei (6.1%), and Bacillus subtilis (3.0%) were detected among clones isolated from soybean paste samples and Halanaerobium sp. (37.5%), Halanaerobium fermentans (37.5%), T. halophila (12.5%), Staphylococcus sp. (6.3%), S. equorum (3.1%), and B. subtilis (3.1%) were detected among clones isolated from soybean sauce. Our approach revealed different bacterial distributions and diversity from those previously obtained using culture-dependent methods.

• 한국자원식물학회지
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• 제12권2호
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• pp.152-160
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• 1999

1. 콩잎의 세균밀도는 4.60$\times$$10^2$~ 9.10$\times$$10^{5}$CFU/$\textrm{cm}^2$으로, 생육단계가 진전됨에 따라 세균밀도가 증가하는 경향이었다. 2. 콩나물 부패 세균의 밀도는 콩잎에서 0~5.00$\times$$10^3$CFU/$\textrm{cm}^2$으로, 부패세균의 밀도는 생육단계에 관련이 없었으나 재배지역과는 관련이 있었다. 3. 나물 콩 품종과 콩나물 부패세균의 밀도는 품종과 관련이 적었으며 생육단계와 작물의 부위에 따라 변이가 심하였다. 4. 콩잎에서 분리된 콩나물 부패세균은 Erwinia cypripedii, E. carotovora subsp. carotovora, Xanthomonas campestris pv. glycines, Staphylococcus sp., Micrococcus sp. 이며, E. carotovora subsp. carotovora, X. campestris pv. glycines가 밀도가 높았다.다.