• 농업과학연구
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• 제47권3호
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• pp.445-457
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• 2020

Prebiotics are defined as "Nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth and activity of bacteria in the intestine" and as defined improve host health. This study was carried out to investigate the effects of bifidobacteria (Bifidobacterium lactis BB12 and Bifidobacterium longum BB536) growth enhancer (BE0623) supplement as a prebiotic. The addition of BE0623, a growth promoting material for bifidobacteria, significantly increased bifidobacteria viable cells counts in fermented milk by about 45 to 75 times compared to the non-added control group. In addition, microscopic observation showed a significant effect on proliferation of bifidobacteria in fermented milk with added BE0623. The viable cell counts in bifidobacteria also increased roughly 102-fold compared to the control group (non-added BE0623) and was higher than that of commercial growth promoters. Each fraction obtained though the purification of BE0623 influenced the increase of bifidobacteria growth. Culturing bifidobacteria with a combination of fractions of BE0623 had a synergistic effect compared to culturing bifidobacteria with each fraction individually. When any of the fractions were not added, the effect of the growth enhancer on bifidobacteria was reduced. These results indicate that all fractions contain substances that promote the growth of bifidobacteria. Therefore, BE0623 is considered to be available as a growth promoting material for bifidobacterium.

• 생명과학회지
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• 제24권12호
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• pp.1308-1315
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• 2014

식물성장촉진 뿌리박테리아(PGPR)을 사용한 생물학적 조절(Biological control)은 최근 몇년 동안에 주목 받게 되었다. PGPR은 산업적으로 중요한 감자, 토마토 그리고 쌀과 같은 경제적으로 중요한 작물의 성장촉진과 관련되어있다. 음식물 쓰레기에서 발견된 Bacillus mojavensis KJS-3은 Aspergillus terreus, A. fumagatus, A. flavus and Fusarium redolense에 대해 항진균작용을 가지고 있는 균주로, 이미 여러 산업적인 측면에서 유용한 가능성이 확인된 균주이다. 본 연구에서는 Bacillus mojavensis KJS-3를 알타리무와 상추에 $0.5{\times}10^9cfu/g$, $1.0{\times}10^9cfu/g$ 및 $2.0{\times}10^9cfu/g$의 3가지 농도로 분무, 재배한 후, 잎의 수, 길이, 무게, 뿌리와 근경의 길이, 넓이 및 무게를 비교함으로써, 이들에 대한 생육촉진작용을 확인해보았다. 그 결과, 처리하지 않은 군에 비하여 Bacillus mojavensis KJS-3를 처리한 군이 더 높은 생육성장을 보였으며, $1.0{\times}10^92cfu/g$농도에서의 재배는 저농도에서의 재배보다 더 높은 생육 성장을 그리고 고농도에서의 재배와 비슷한 생육성장을 나타내었다. 이러한 결과를 토대로 B. mojavensis KJS-3의 생물학적 비료로서의 가능성을 확인할 수 있었으며, 또한 B. mojavensis KJS-3의 다른 작물에 대한 생육조절제의 적용도 가능할 것으로 예상된다.

• Journal of Microbiology and Biotechnology
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• 제21권6호
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• pp.556-566
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• 2011

A total of 31 Acinetobacter isolates were obtained from the rhizosphere of Pennisetum glaucum and evaluated for their plant-growth-promoting traits. Two isolates, namely Acinetobacter sp. PUCM1007 and A. baumannii PUCM1029, produced indole acetic acid (10-13 ${\mu}g$/ml). A total of 26 and 27 isolates solubilized phosphates and zinc oxide, respectively. Among the mineral-solubilizing strains, A. calcoaceticus PUCM1006 solubilized phosphate most efficiently (84 mg/ml), whereas zinc oxide was solubilized by A. calcoaceticus PUCM1025 at the highest solubilization efficiency of 918%. All the Acinetobacter isolates, except PUCM1010, produced siderophores. The highest siderophore production (85.0 siderophore units) was exhibited by A. calcoaceticus PUCM1016. Strains PUCM1001 and PUCM1019 (both A. calcoaceticus) and PUCM1022 (Acinetobacter sp.) produced both hydroxamate-and catechol-type siderophores, whereas all the other strains only produced catechol-type siderophores. In vitro inhibition of Fusarium oxysporum under iron-limited conditions was demonstrated by the siderophore-producing Acinetobacter strains, where PUCM1018 was the most potent inhibitor of the fungal phytopathogen. Acinetobacter sp. PUCM1022 significantly enhanced the shoot height, root length, and root dry weights of pearl millet seedlings in pot experiments when compared with controls, underscoring the plant-growth-promoting potential of these isolates.

• 한국미생물·생명공학회지
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• 제30권4호
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• pp.380-387
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• 2002

대한제당(주) 중앙연구소에서 기능성 감미료로서 개발한 자일로올리고당이 장내세균의 생장에 미치는 영향을 알아보기 위하여 in vitro실험을 하였다. 탄소원 이용능을 알아보기 위하여 당이용능검색배지인 m-PYF medium에 탄소원으로서 자일로올리고당과 시판중인 올리고당인 이소말토올리고당과 프럭토올리고당, sucrose를 각각 0.5%(w/v) 첨가한 후 여러 장내 세균을 각각 배양하였다. 장내유익균인 Bifidobacterium bifidum, Bifidobacterium infantis, Bifidobacterium longum, Lactobacillus casei 및 Lactobacillus acidophilus는 다른 탄소원보다 자일로올리고당이 첨가된 배지에서 훨씬 더 잘 생장하였으나, Clostridium perfringens, Bacteroides fragilis, Escherichia coli, Staphylococcus aureus와 Salmonella typhumurium 등 장내 유해균은 생장이 저해되었다 또한, 이들 세균을 혼합배양한 경우에도 장내 유익균의 생균수는 증가하였고, 유해균은 상대적으로 낮은 농도로 억제되었다. 충치를 유발하는 원인 균주인 Strepto-coccus mutans를 자일로올리고당이 첨가된 m-PYF medium에서 배양하였을 때 배양액의 pH가 5.0이상으로 유지되었다. 이러한 결과들을 볼 때 자일로올리고당은 인체의 장내 유익균에만 선택적으로 작용하여 생장을 증진시킬 뿐 아니라, S. mutans의 생장시 산 생성을 억제함으로써 충치 발생을 예방할 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.249-257
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• 2002

Pseudomonas fluorescens GL20 is a plant growth-promoting rhizobacterium that produces a large amount of hydroxamate siderophore under iron-limited conditions. The strain GL20 considerably inhibited the spore germination and hyphal growth of a plant pathogenic fungus, Fusarium solani, when iron was limited, significantly suppressed the root-rot disease on beans caused by F. solani, and enhanced the plant growth. The mechanism for the beneficial effect of strain GL20 on the disease suppression was due to the siderophore production, evidenced by mutant strains derived from the strain. Analysis of the outer membrane protein profile revealed that the growth of strain GL20 induced the synthesis of specific iron-regulated outer membrane proteins with molecular masses of 85- and 90 kDa as the high-affinity receptors for the ferric siderophore. In addition, a cross-feeding assay revealed the presence of multiple inducible receptors for heterologous siderophores in the strain. In order to induce increased efficacy and potential in biological control of plant disease, a siderophore-overproducing mutant, GL20-S207, was prepared by NTG mutagenesis. The mutant GL20-S207 produced nearly 2.3 times more siderophore than the parent strain. In pot trials of beans with F. solani, the mutant increased plant growth up to 1.5 times compared with that of the parent strain. These results suggest that the plant growth-promoting P. fluorescens GL20 and the genetically bred P. fluorescens GL20-S207 can play an important role in the biological control of soil-borne plant diseases in the rhizosphere.

• Journal of Microbiology and Biotechnology
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• 제28권9호
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• pp.1527-1535
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• 2018

Bacterial strain BAS23 was isolated from rice field soil and identified as Bacillus amyloliquefaciens. Based on dual culture method results, the bacterium BAS23 exhibited potent in vitro inhibitory activity on mycelial growth against a broad range of dirty panicle fungal pathogens of rice (Curvularia lunata, Fusarium semitectum and Helminthosporium oryzae). Cell-free culture of BAS23 displayed a significant effect on germ tube elongation and mycelial growth. The highest dry weight reduction (%) values of C. lunata, H. oryzae and F. semitectum were 92.7%, 75.7%, and 68.9%, respectively. Analysis of electrospray ionization-mass spectrometry (ESI-MS) and $^1H$ nuclear magnetic resonance (NMR) spectroscopy revealed that the lipopeptides were iturin A with a C14 side chain (C14 iturinic acid), and a C15 side chain (C15 iturinic acid), which were produced by BAS23 when it was cultured in nutrient broth (NB) for 72 h at $30^{\circ}C$. BAS23, the efficient antagonistic bacterium, also possessed in vitro multiple traits for plant growth promotion and improved rice seedling growth. The results indicated that BAS23 represents a useful option either for biocontrol or as a plant growth-promoting agent.

• 한국유기농업학회지
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• 제7권1호
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• pp.129-135
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• 1998

암면경, 펄라이트경 및 코코피트경 토마토의 생장촉진에 미치는 근권세균류의 영향을 구명하기 위하여 $Azospirilham\;sp.(4.5{\times}10^7cells/g),\;Rhodopseudomonas\;sp.(5.8{\times}10^5cells/g),\;Pseudomonas\;sp.(6.1{\times}10^6cells/g$) 및 Bacillus sp. 와 Corynebacterium glutamicum의 융합체($9.1{\times}10^5cells/g$) 등의 군주를 근권에 처리하였다. 군주의 근권처리시 토마토의 전반적인 생장이 대조구에 비해서 촉진되었으며, 식물생장촉진효과가 가장 우수한 군주는 Azospirillum sp.였다. 군주에 의한 식물생장 촉진 효과가 높은 재배방식 및 배지는 코코피트경 > 필라이트경 = 암면경 등의 순이었다.

• Journal of Nutrition and Health
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• 제28권11호
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• pp.1065-1072
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• 1995

Mugwort was successively fractionated with n-hexane, chloroform, ethyl acetate, n-butanol and water and the fractions were evaluated by their growth-promoting activites for Bifidobacterium sp. in vitro experiments. The growths of Bifidobacterium adolescentis, B. bifidum, B. infantis and B.longum were enhanced with the addition of the water fraction, while the fractions of chloroform and ethylacetate inhibited Clostridium perfringens. When the wate fraction was added to media at a concentration of 0.01-0.5%(w/v), the growhts of Bifidobacterium sp. were increased according to the concentration of water fraction used. The water fraction stimulated also the growth of lactobacillus acidophillus, whereas those of E. coli and Enterococcus faecalis were not affected. The growth-promoting activity of water fraction was stable at the range of pH 2 to pH 10 and kept in thermal treatment at 10$0^{\circ}C$ for 30 minutes.

• Journal of Plant Biology
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• 제12권3호
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• pp.43-49
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• 1969

This study is an evaluation of growth-promoting effects of methyl and ethyl alcohol on Korean radish and cabbage in the soil. In an experiment as College of Education, Seoul National University, Silt loams, which are treated seven times with methyl and ethyl alcohol at rates from 0.5cc. to 2.5cc. per pot, definitely increase growth rate of radish and cabbage seedlings originating from sterilized seeds. A strong, stimulating effect on the growth of radish and cabbage seedlings is produced when a rate of 0.5cc. per pot of alcohol is applied to pot soils. The effect of methyl alcohol is stronger in fresh weight, dry weight, and average height of radish and cabbage than that of ethyl alcohol.

• 한국시스템다이내믹스연구
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• 제3권2호
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• pp.5-27
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• 2002

This paper evaluate and compare effectiveness of urban growth management measures in Korea using system dynamics model. Simple urban dynamics model was used to compare urban growth management measures. Since the late 1960s, Korean government has been implementing various urban growth management measures without much success. In the 1960s, factories, universities, and public agencies were strongly encouraged to move out to local areas. During the 1970s, regulations on greenbelt area was adopted to prevent urban sprawl. Besides, regulations to prevent location of population inducing facilities, and promoting dislocation of those facilities were implemented simultaneously. During the 1990, regulations on total number of factories in the metropolitan area, development fees were adopted. These various method of urban management were compared. Simulation results shows that promoting decentralization of population, preventing population immigration, expanding greenbelt area are effectiveness ones compared to controlling total number of population inducing facilities, and preventing construction of new industries. Some implications of the findings were discussed.