• Korean Journal of Agricultural Science
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• v.47 no.3
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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.

• Journal of Life Science
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• v.24 no.12
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• pp.1308-1315
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• 2014

Biological control using the plant growth-promoting Rhizobacterium (PGPR) has received significant attention in recent years. PGPR has been linked with promoting growth in economically important crops, such as potatoes, tomatoes, and rice. Bacillus mojavensis KJS-3 (Moja-3), isolated from food waste, possesses antifungal properties against Aspergillus terreus, A. fumagatus, A. flavus, and Fusarium redolense, and it may have potential in the development of products for industrial applications. The main purpose of this study was to determine the effects of spraying the PGPR Bacillus mojavensis KJS-3 on the growth of altari radish (leaf number, leaf length, leaf weight, root length, and rhizome length, adjacent portion diameter, and weight) and lettuce (leaf number, length, width, and weight). Three different concentrations of the foliar spray treatment of B. mojavensis KJS-3 were applied to the altari radish and lettuce: the recommended standard concentration of $1{\times}10^9cfu/g$, half the standard concentration of $0.5{\times}10^9cfu/g$, and double the standard concentration of $2{\times}10^9cfu/g$). The B. mojavensis strain foliar spray treatment increased the growth of the leaves and roots of the altari radish and increased the growth of the lettuce leaves. For both plants, the recommended concentration of B. mojavensis KJS-3 produced better growth than half the standard concentration, and the growth was similar with the double dose. This study demonstrates positive effects of Moja-3, suggesting it may be a potential new bio-fertilizer for improving the growth of altari radish and lettuce.

• Journal of Microbiology and Biotechnology
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• v.21 no.6
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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.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.380-387
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• 2002

To investigate the effects of xylooligosaccharides on the in vitro growth of intestinal bacteria, various species were cultivated individually on the m-PYF medium containing a carbon source (0.5% w/v) such as xylooligosaccharides, isomaltooligosaccharides, fructooligosaccharides and sucrose, respectively. The health-promoting microorganisms such as Bifidobacterium bifidum, Bifidobacterium infantis, Bifidobacterium longum, Lactobacillus casei and Lactobacillus acidophilus grew more effectively by xylooligosaccharides than by other carbon source, though xylooligosaccharides inhibited the growth of Clostridium perfringens, Bacteroides fragilis, Escherichia coli, Staphylococcus aureus and Salmonella typhumurium. At the mixed culture xylooligosaccharides exerted a preferential stimulatory effects on numbers of the health-promoting microorganisms, while xylooligosaccharides inhibited populations of potential pathogens at relatively low level. Xylooligosaccharides also maintained the acidity of culture with Streptococcus mutans, caries-inducing bacteria, over pH 5.0. These results suggest that xylooligosaccharides selectively promote the growth of the health-promoting microorganisms in human intestine and prevent caries by inhibiting acid production from Streptococcu mutans.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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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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• v.28 no.9
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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.

• Korean Journal of Organic Agriculture
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• v.7 no.1
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• pp.129-135
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• 1998

This study was conducted to clarify the plant growth promoting effects of the various rhizobacteria on the growth of hydroponically grown tomatoes in rockwool, perlite and cocopeat cultures. Strains in terms of $Azospirilham\;sp.(4.5{\times}10^7cells/g),\;Rhodopseudomonas\;sp.(5.8{\times}10^5cells/g),\;Pseudomonas\;sp.(6.1{\times}10^6cells/g$), fusant of $Bacillus\;sp.\;and\;Corynebacterium\;glutamicum(9.1{\times}10^5cells/g$) was bacterialized into the root zone of tomatoes before sowing. Overall growth of tomato plants was promoted by bacterialization of the various rhizobacteria. Strains which showed the highest plan growth promoting effects of hydroponically grown tomatoes was Azospirillum sp., and optimum cultural substrates for the plant growth promotion by rhizobactera were in the order of cocopeat > perlite = rockwool cultures.

• Journal of Nutrition and Health
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• v.28 no.11
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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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• v.12 no.3
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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.

• Korean System Dynamics Review
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• v.3 no.2
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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.