• Toxicological Research
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• v.23 no.4
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• pp.373-382
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• 2007

This study was conducted to obtain acute information of the oral dose toxicity of PGB-1, a novel polyglucosamine polymer produced from a new strain Enterobacter sp. BL-2 in male and female mice. In order to calculated 50% lethal dose ($LD_{50}$) and approximate lethal dose (LD), test material was once orally administered to male and female ICR mice at dose levels of 2000, 1000, 500, 250, 125 and 0 (vehicle control) ml/kg (body wt.). The mortality and changes on body weight, clinical signs, gross observation and organ weight and histopathology of principle organs were monitored 14 days after dosing with PGB-1. We could not find any mortalities, clinical signs, body weight changes and gross findings. In addition, significant changes in the organ weight and histopathology of principal organs were not observed except for some sporadic findings. The results obtained in this study suggest that PGB-1 may not be toxic in mice and may be therefore safe for clinical use. The $LD_{50}$ and approximate LD in mice after single oral dose of PGB-1 were considered over 2000 mg/kg in both female and male mice.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.10
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• pp.672-678
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• 2014

In this study, variations of fermentative hydrogen production and microbial community were investigated with different nitrogen concentration of food waste. Optimum hydrogen production rate was acquired at 200 mg/L nitrogen concentration of the food waste. Which was eqivalent to 83.43 mL/g dry biomass/hr. However, bio-hydrogen production was inhibitedly reduced at over 600 mg/L of nitrogen concentration whereas proportional relation between hydrogen production and B/A ratio were not observed. Most dominant specie of the microbial community analyzed was Clostridium sp. throughout PCR-DGGE analysis of 16S rDNA. It revealed that most contributing microorganism producing hydrogen were Enterococcus faecium partial, Klebsiella pneumoniae strain ND6, Enterobacter sp. NCCP-231, and Clostridium algidicarnis strain E107 in this experiment.

• Korean journal of applied entomology
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• v.26 no.2 s.71
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• pp.89-97
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• 1987

Antagonistic microorganisms from rhizosphere soil were isolated, identified, and applied successfully as the biocontrol agents of damping-off caused by Rhizoctonia spp. Rhizosphere antagonists isolated from rhizosphere soil were identified as Trichoderma viride, T. harzianum, T. hamatum, T. polysporum, Gliocladium sp., Pseudomonas fluorescence, P. stutzeri, P. cepacia, Enterobacter sp., Serratia sp. and Erwinia herbicola. Of these, the most promising ones in vitro were T. virdie, T. harzianum, Gliocladium sp., Serratia sp., P. stutzeri, and P. cepacia. These above six antagonists were efficient in reducing disease incidence to $40{\sim}70%$ when the reselected rhizosphere antagonists preparations were applied to the soil at $10^6$ propagules per gram. Among six antagonists, T. viride was the most promising biocontrol agents against R. solani isolates in soil. The suppressive effect was more evident in steam-sterilized soil than in non-sterilized field soil.

• Food Industry And Nutrition
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• v.2 no.1
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• pp.16-21
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• 1997

Microbial of enzymatical methods are suitable for production of rare monosaccharides. Using oxidation and reduction ability of Microorganisms, various rare ketoses and polyols can be produced, for example D-tagatose from galagtitol by Enterobacter agglomerans strain 221e. L-tagatose from galactitol by Klebsiella pheumonias strain 40b, L-psicose from allitol by Gluconobacter frateurii IFO 3254, D-talitol from d-tagatose by Aureobasidium pullulans strain 113B, allitol from D-psicose by Enterobacter agglomerans strain 221e and so on. We can produce various rare aldoses and ketoses using aldose isomerases, for example L-galactose from L-tagatose by D-arabnose isomerase, and L-ribose from L-ribulose by L-isomerase, and so on. D-Tagatose 3-epimerase of Pseudomonas sp. ST-24 is very useful for preparationof various rare ketoses, for example D-psicose from D-fructose, D-sorbose from D-tagatose, L-fructose, from L-psicose and so on. Using polyol dehydrogenases, aldose isomerases and D-tagatose 3-epimerase, we can design the suitable for production of a certain rare monosaccharide from a suitable substrate.

• KSBB Journal
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• v.26 no.5
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• pp.407-411
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• 2011

Microbial fuel cell (MFC) wes enriched using sludge in wastewater treatment. The microbial community of activated sludge and enriched MFC were analyzed by FISH (fluorescent in situ hybridization) and 16S rDNA sequencing. Bacteroidetes group were pre-dominant in activated sludge by FISH. ${\alpha}$ group, ${\gamma}$ group and Acintobacter group were dominant and they were similar to distribution. The average value of 10 peak of MFC is 0.44C. When MFC wase enriched by sludge, ${\gamma}$-Proteobacteria, Plantomycetes group increased 70% and 60%, respectively. In results of 16S rDNA sequencing, Sphiringomonas sp. was comprised in ${\alpha}$ proteobacteria and Enterobacter sp., Klebsiella sp., Acinetobacter sp., Bacillus sp. were comprised in ${\gamma}$ proteobacteria and Chryseobacterium sp. was comprised in Flavobacteria were isolated from sludge.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.515-520
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• 2013

Bacterial communities derived from cheonggukjang and raw rice straw collected from a Mireuksan farm and a Heungup cheonggukjang in Gangwon province were investigated using both culture-based method and denaturing gradient gel electrophoresis (DGGE) analysis. Pure cultures, which were isolated from raw rice straw and cheonggukjang and cultured on tryptic soy agar plates (53-76 colonies per plate), were identified by analysis of 16S rRNA sequences. The traditional culture-based method and analysis of PCR-amplified 16S rRNA by DGGE revealed that for samples collected from the Mireuksan farm, Pantoea agglomerans and Bacillus subtilis were the predominant species in the raw rice-straw and cheonggukjang, respectively. For samples collected from the Heungup cheonggukjang, Bacillus amyloliquefaciens was the predominant species in both raw rice straw and cheonggukjang. Other microorganisms, including members of Pantoea, Bacillus, Enterococcus, Enterobacter, Pseudomonas, Rhodococcus, and Acinetobacter, were also present in the raw rice-straw and cheonggukjang, as were bacteria that could not be cultured.

• YAKHAK HOEJI
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• v.21 no.4
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• pp.193-199
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• 1977

ABS, Alkyl benzene sulfonate, persists for long periods in stream because of its resistance to biologic degradation. Its bio-degradation is very varied in the environments. This investigation was therefore undertaken in order to know the biodegradation of synthetic detergents which are comprising soft and hard forms from February 1976 to September 1976. The biodegradations by spontaneuos settling and aeration were determined. The reduction rates of ABS, DBS, and LAS were 9.8%, 13.7% and 10.4% by the settlings for 5 days at $25^{\circ}$ and 63.3%, 27.2%, and 43.9% by aeration respectively. It was not contributed effectively to biodegradate the synthetic detergents by the simulaneous incubation with micro-organisms isolated from sewage such as Enterobacter sp., E. coli, Bacillus sp., Flavobacterium sp., Pseudomonas sp., Staphylococcus sp., and etc. Tricking filter could also eliminate some amount of detergent. By the application of this investigation, it could be designed that detergents would be regulated in abuse in context with water pollution and be treated at a proper process in the sewage treatment plant to be installed.

• Journal of Mushroom
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• v.19 no.3
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• pp.134-139
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• 2021

A diverse group of plant-growth promoting bacteria were isolated in button mushroom (Agaricus bisporus) media to investigate the plant-growth promoting traits of compounds including indole acetic acid (IAA), ammonia, 1-aminocyclopropane-1-carboxylic acid deaminase, siderophore, and hydrogen cyanide. Twenty-one bacterial strains showing positive effects for all the test traits were selected and classified to confirm bacterial diversity in the media habitat. Plant-growth promoting traits of the isolates were also assessed. All strains produced IAA ranging from 20 ㎍/mL to 250 ㎍/mL. Most of the isolates produced more than 80% siderophore. Four strains (Pantoea sp., PSB-08, Bacillus sp., PSB-13, Pseudomonas sp., PSB-17, and Enterobacter sp., PSB-21) showed outstanding performances for all the tested traits. In a bioassay of these four strains using mung bean plant, the best growth performances (23.16 cm, 22.98 cm, 2.27 g/plant, and 1.83 g/plant for shoot length, root length, shoot dry weight, and root dry weight, respectively) were obtained from the plants co-inoculated with Bacillus sp., PSB-13. The resultant data indicate that button mushroom media have got a diverse group of bacteria with plant growth promoting abilities. Thus, the media could be a good recycling resource for using to an effective bio-fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.29-36
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• 2009

Fourteen bacterial strains were isolated from crop rhizosphere and identified as phosphate solubilizing bacteria (PSB) by 16S rRNA analysis. Only 3 strains exhibited a strong ability to solubilize insoluble phosphate in agar medium containing a hydroxyapatite. The rates of P solubilization by isolates were ranged from 200 and $2300\;mg\;L^{-1}$, which are inversely correlated with pH in culture medium. Furthermore, HPLC analyses reveal the production of organic acid from the culture filtrates of PSB. Among these, strain Acinetobacter sp. released only gluconic acid, Pseudomonas orientalis produced gluconic acid which was subsequently converted into 2-ketogluconic acid, and Enterobacter asburiae released acetic acid and succinic acid. On the other hand, P. orientalis and E. asburiae released $372\;mg\;L^{-1}$ and $191\;mg\;L^{-1}$ of IAA into broth culture, respectively, while Acinetobacter sp. did not produce IAA. Furthermore, in vivo study showed that plant growth promoting effect by bacteria generally seemed to be increased IAA production and phosphate solubilization.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.148-148
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• 2005