• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.271-275
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• 1998

Controversial observations on the effect of pre-attached bacteria on the attachment of diatoms to artificial surfaces immersed in seawater have been made. Furthermore, it is not known whether or not pre-attached bacteria on artificial surfaces influence attachment of diatoms in natural seawater. In this study, we used various surfaces to which marine bacteria were pre-attached for different incubation periods. In the first experiment, glass slides were initially attached by marine natural bacteria with different exposure time (0-133 hr) and then immersed into seawater for a certain time period. The attachment of diatoms was not affected by the abundance of pre-attached bacteria (p > 0.05). The maximum abundance of attached diatoms was found on control surfaces, and the minimum abundance on surfaces where attached bacterial abundance was highest. In the second experiment, glass slides and acryl slides, either attached by marine natural bacteria for 6 days or coated by agar, were immersed in seawater. Untreated slides were also employed. On the surfaces of acryl slides with the most abundant attached bacteria ($5.4{\pm}0.02{\times}10^5\;cells\;cm^{-2}$), abundances of attached diatoms were less than those on untreated slides. On the surfaces of glass slides with bacterial abundance of $2.5{\pm}1.0{\times}10^5\;cells\;cm^{-2}$, however, abundances of attached diatoms were not different from those of untreated slides. On the agar-coated slides, the immigration rate and immigration coefficient were on average > 2 folds compared to other surfaces, indicating high rates of diatom attachment on mucilage simulated surfaces. Therefore, it seems that pre-attachment of bacteria is not prerequisite for the attachment of diatoms on artificial surfaces.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.7
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• pp.833-838
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• 2007

In this study, adhesion and transport of bacteria in positively-charged media was investigated with batch and column experiments. Bacterial species used in this study was Escherichia coli ATCC 11105(length: 2.2 ${\mu}m$, diameter: 0.6 ${\mu}m$) and media used were quartz sand(particle size distribution: 0.5-2.0 mm, mean diameter: 1.0 mm) and iron-coated sand. Batch results indicate that bacterial adhesion increased as the content of iron-coated media increased. At iron-coated media 0%(quartz sand 100%), around 46% of bacteria was adhered to media while at iron-coated media 100%(quartz sand 0%) about 97% was attached. Column results also show that bacterial adhesion was enhanced with an increase of iron-coated media content. As the iron-coated media content increased from 0 to 100%, bacterial adhesion increased from 8 to 94%. The experimental results demonstrate that positively-charged media could influence transport of bacteria in porous media.

• 한국해양학회지
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• v.24 no.3
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• pp.148-156
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• 1989

This investigation was performed in eutrophic lake within the framework of a series of studies to evaluate the significance of gram reaction for both bacterioplankton and attached bacteria in the dynamics of organic materials at various aquatic ecosystems. In Lake Kasumigaura as a representative of the highly eutrophic freshwater environments, the gram-stain characteristics of the bacterial community changed with the influx of pulses of phytoplankton, as those in the meso trophic environments. The predominency of the gram-negative forms in the bacterial community was about 57% for bacterioplankton and about 53% for attached bacteria. The statistical analysis of the difference of these two distributions showed that these communites were different. Both gram-negative and gram-positive bacteria attached to particles were shown to effect the formation and degradation of particulate organic matter. Gram-negative bacteria plankton participate exclusively in the dynamics of dissolved organic matter.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.616-620
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• 2008

The aim of this study was to investigate the influence of phosphate on the adhesion of Escherichia coli to porous media. Column experiments were performed to examine the effect of phosphate on bacterial adhesion to quartz sand and iron-coated sand. Results showed that bacterial mass recovery in quartz sand decreased from 74.5 to 35.4% as phosphate concentration increased from 0 to 16 mg/L. This indicated that bacterial adhesion to quartz sand was enhanced with increasing phosphate concentration. This phenomenon is due to the increase of ionic strength. In contrast, the mass recovery in the coated sand increased from 2.9 to 26.0% as phosphate concentration increased. This indicated that bacterial adhesion to the coated sand was reduced with increasing phosphate concentration, due to the preoccupation of favorable adsorption sites and competitive adsorption by phosphate.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.8
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• pp.533-540
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• 2012

The concentration of organic compounds was analyzed at each step of BAC (biological activated carbon) process though BDOC (biodegradable dissolved organic carbon) total/rapid/slow. Further, bacteria communities and biomass concentrations measured DGGE (denaturing gradirnt gel electrophoresis) and ATP (adenosine triphosphate) methods were analyzed. The bed volume of steady state is different based on assessment of organic compounds removal. Bed volumes at steady state in DOC, $BDOC_{rapid}$ and $BDOC_{total/slow}$ removal were around 27,500, 15,000 and 32,000, respectively. A biomass didn't change after the bed volume reached 22,500 according to analyzing HPC (heterotrophic plate count) and ATP concentration of bacteria. The concentration of HPC and ATP were $3.3{\times}10^8$ cells/g and $2.14{\mu}g/g$, respectively. The number of the DGGE band were only 5 at the bed volume 8,916, but increased up to 11 at the bed volume 49,632. As operation time increase, bacterial group were more diversity. Four bacteria species including Pseudomonas fluorescens, the uncultured bacterium similar to Acinetobacteria, uncultured Novosphingobium sp. and Flavobacterium frigidarium have detected from the early stages and Proteobacteria group were dominantly detected.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.60-67
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• 2014

The comparisons between cellulolytic bacteria adhesion on rice straw and fiber digestion in time course during rumen fermentation were studied in situ. The adhesions of cellulolytic bacteria, F. succinogenes. R. albus and R. flavefaciens, were measured by RT-PCR. When the rice straws were incubated at 0. 2, 4, 8, 12 and 24 hours of the in situ rumen, straw was degraded with increasing speed during the incubation and showed the highest disappearance increasing rate (DM g/h) from 8 to 12 hour. The adhesions of F. succinogenes, R. flavefaciens and R. albus were achieved above 80% in 1 hour of in situ rumen fermentation and then keep adhesive population up after the time of fermentation. When the in situ samples were collected at 0, 5, 10, 30 and 60 min to detect the early stages of adhesion on the rice straws ingested into rumen, the numberous adhesive colony of F. succinogenes, R. flavefaciens and R. albus were detected in 5 min. In case of rice straw treated with 0, 2, 4 and 8% NaOH, all of three cellulolytic bacteria showed the increasing trends of adhesion with increasing DM disappearance of rice straw by higher concentration of NaOH at 12 hour of in situ. However, there were showed respectively difference at 24 hour. The present results gave certain evidence that adhesion of cellulolytic bacteria is definitely achieved in early stage of roughage ingestion into rumen, their colony develop the stable communities on roughage in process of rumen fermentation and then fiber degradation is accelerated.

• Journal of the Mineralogical Society of Korea
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• v.23 no.4
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• pp.315-329
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• 2010

Characteristics of thermophilic bacteria and secondary materials on the pyrrhotite surface were investigated by using scanning electron microscopy (SEM). The thermophilic bacteria from an acid hot spring in Japan were incubated with pyrrhotite at $42^{\circ}C$, $52^{\circ}C$, and $62^{\circ}C$ respectively. SEM analysis of the reacted pyrrhotite showed that indigenous rod-shaped bacteria ranging from $0.4{\times}1.5{\mu}m$ to $0.3{\times}11.9{\mu}m$ in size were attached to the pyrrhotite surface at these temperatures with formation of secondary materials. Extracellular polymer substances were formed on the bacterial surface. We suggest that these polymers functioned as a capsule protecting bacteria from the extreme environment. Secondary materials such as elemental sulfur, Fe-hydroxide, S-Fe and O-P-Fe compounds were found on the pyrrhotite surface.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.35-43
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• 2017

This study was to research the relationships between rice straw degradation and changes of fibrolytic bacteria population during the in vitro rumen fermentation. Dry matter(DM) digestion of rice straw and population of fibrolytic bacteria were measured at the 0. 4, 8, 12 and 48 hours during the incubation. The populations of F. succinogenes. R. albus and R. flavefaciens were defined as log copy number of 16S rDNA by technical method of Quantitative real-time PCR. Total population of F. succinogenes, R. flavefaciens and R. albus was sum of bactera attached on rice straw and suspended in medium. It's population was increased with incubation, reached top level of 29.0 Log copy No at the 24 hour and then decreased. In the meantime, DM digestion of rice straw showed the higher increasement from the 8 hour to the 24 hour than from the 0 hour to the 8 hour, and then a slowdown in increasing trend of digestibility. Attachments of F. succinogenes, R. flavefaciens and R. albus were detected immediately after start of in vitro rumen incubation. At the same time, the colonized bacterial share were respectively 34.5%, 84.4% and 67.9% in total population. All of them was reached the highest colonized bacterial share above 94.7% at the 4 hour incubation. However population of attached bacteria was shown the highest level at the 12 hour or the 24 hour incubation. Kinetics of colonization were formed area of top speed from the 12 hour to the 24 hour and respectively reached 10.33, 9.28 및 8.30 Log copy No/h/g DM at the 24 hour by F. succinogenes, R. flavefaciens and R. albus. The kinetics of rice straw degradation was formed top level of 0.95% DM/h at the 24 hour. The present results gave clear evidence that degradation of rice straw was increased with the development of total fibrolytic bacteria in process of rumen fermentation. Also, their attachment was largely occurred immediately after insertion of rice straw, the colonized bacteria was actively proliferated, and then degradation of rice straw was maximized.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.119-124
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• 2009

The aim of this study was to investigate the influence of ionic strength and iron impregnation on the attachment of Enterococcus faecalis to granular activated carbon (GAC). Column experiments were performed to examine bacterial adhesion to coconutbased GAC (c-GAC), iron-impregnated c-GAC (fc-GAC), acid-washed c-GAC (a-GAC) and iron-impregnated a-GAC (fa-GAC) under two different solution (NaCl 1, 10 mM) conditions. Results showed that bacterial mass recovery in c-GAC decreased from 77.3 to 61.6% while in a-GAC it decreased from 71.6 to 32.3% with increasing ionic strength from 1 to 10 mM. This indicates that bacterial attachment to GAC can be enhanced with increasing ionic strength. Results also showed that the mass recoveries in fc-GAC were 62.6% (1 mM) and 53.3% (10 mM) while they were 50.8% (1 mM) and 16.9%(10 mM) in fa-GAC, which were lower than those in c-GAC and a-GAC. This demonstrates that bacterial adhesion to GAC can be enhanced through iron impregnation. This study provides information regarding the effects of ionic strength and iron impregnation on bacterial attachment to GAC. Furthermore, this study will advance our knowledge of bacterial removal in surface-modified granular media.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.515-520
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• 2009

This study investigated the influence of oxyanions (nitrate, carbonate, phosphate) on the attachment of bacteria (Bacillus subtilis) to Al-Fe bimetallic oxide-coated sand using column experiments. Results showed that bacterial attachment to the coated sand was independent of nitrate concentration. Bacterial mass recovery remained constant (10.9${\pm}$0.2%) with varying nitrate concentrations (0.1, 1, 10 mM). In case of carbonate, mass recovery increased from 25.6% to 39.0% with increasing carbonate concentration from 0.1 mM to 1 mM, and mass recovery also increased from 50.9% to 78.9% at the same concentration condition in case of phosphate. This phenomenon could be attributed to the hindrance effect of carbonate and phosphate to bacterial attachment to the coated sand. Meanwhile, with increasing carbonate/phosphate concentration from 1 mM to 10 mM, mass recovery decreased from 39.0% to 23.8% and from 78.9% to 52.6%, respectively. This phenomenon could be ascribed to the enhancement effect of free carbonate/phosphate ions present in solution phase due to increasing carbonate/phosphate concentration, which increase ionic strength and thus enhance bacterial attachment to the coated sand. In our experimental conditions, the effect of phosphate to bacterial attachment to the coated sand was the greatest among phosphate, carbonate, and nitrate.