• Korean Journal of Microbiology
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• v.6 no.3
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• pp.92-92
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• 1968

1) The aim of present investigation is to elucidate the relation of the balance of the production and decomposition of the fir litter. in Kwangnung plantation stands. 2) The decay constant, K, of litters was 0. 185 for the fir stand at Kwangnung. 3) The mode for the accumulation of organic carbon ($C_a$) is $c_a$= $610(1-e^{-0.185t})$), and for the decay of organic carbon (C) C = $610(1-e^{-0.185t})$. 4) The time required for the decay of half of the accumulated organic carbon in the fir stand is 3. 74 years and for 99% of elimination 27.02 years. 5) The litters of Abies holophylla killed by heat and washed with alcohol-benzol, with hot water, or with both alcohol-benzol and hot water were incubated after inoculated with suspension of firwood soil. Plate counts were made of fungi and bacteria from time to time. 6) Removal of the alcohol-benzol soluble substance stimulates at the beginning of the decay the growth of fungi and also of bacteria. 7) Removal of the water soluble fraction is detrimental to the growth of fungi in particular. 8) The distribution of soil microbial population is higher in both F and H horizon of the fir plantation soil in Kwangnung. However, the number of soil microorganisms decreases with the depth in forest soil.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.93-99
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• 1968

1) The aim of present investigation is to elucidate the relation of the balance of the production and decomposition of the fir litter. in Kwangnung plantation stands. 2) The decay constant, K, of litters was 0. 185 for the fir stand at Kwangnung. 3) The mode for the accumulation of organic carbon ($C_a$) is $c_a$= $610(1-e^{-0.185t})$), and for the decay of organic carbon (C) C = $610(1-e^{-0.185t})$. 4) The time required for the decay of half of the accumulated organic carbon in the fir stand is 3. 74 years and for 99% of elimination 27.02 years. 5) The litters of Abies holophylla killed by heat and washed with alcohol-benzol, with hot water, or with both alcohol-benzol and hot water were incubated after inoculated with suspension of firwood soil. Plate counts were made of fungi and bacteria from time to time. 6) Removal of the alcohol-benzol soluble substance stimulates at the beginning of the decay the growth of fungi and also of bacteria. 7) Removal of the water soluble fraction is detrimental to the growth of fungi in particular. 8) The distribution of soil microbial population is higher in both F and H horizon of the fir plantation soil in Kwangnung. However, the number of soil microorganisms decreases with the depth in forest soil.

• KSBB Journal
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• v.14 no.2
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• pp.198-204
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• 1999

Asymbiotic bacterium with highly effective toxins was isolated from entomopathogenic nematode Steinernema glaseri which has been widely used against various soil-inhabiting pests. The symbiont of S. glaseri was identified as Xenorhabdus nematophilus sp. by using several biochemical and physiological tests. When this strain was released into the hemolymph of insect larva, it produced highly toxic substances and killed the larva within 2 days. Two colony forms that differed n some biochemical characteristics were observed when cultures in vitro. Phase l colonies were mucid and difficult to be dispersed in liquid. Phase II was not mucoid and was easily dispersed in liquid. It did not adsorb neutral red or bromothymol blue. Rod-shaped cell size was highly variable between two phases, ranging 2-10 ${\mu}{\textrm}{m}$. It was also found that only infective-stage nematodes can carry only primary-phase Xenorhabdus in their intestine.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.393-398
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• 1996

In order to develop a lactic acid bacterial powder which can be used as a probiotic for human and animal, a lactic acid bacteria which has high resistance against low pH and ox-gall, and shows a good growth inhibition against E. coli, was isolated from an animal intestine and characterized. The isolated strain was identified as Enterococcus faecium. It had more than 90% of survival at low pH for 2 hours and almost 100% of survival in the presence of 0.3% ox-gall. When co-cultured with E. coli in MRS broth, all of the E. coli cells were killed within 24 hours. The final powdered product of the isolated strain was manufactured after a freeze drying process using an industrial media, and then checked its stability. Its storage stability was 80% for 11 months at 18$\circ$C.

• Journal of the Korean Society of Clothing and Textiles
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• v.19 no.3
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• pp.548-559
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• 1995

The purpose of this study was 1) to investigate the effect of drycleaning on the removal of microorganisms according to on the conditions or the kinds of drycleaning solvent about the Quantity of microorganism which remains in kinds of the drycleaning solvent and the sludge after drycleaning. 2) to investigate the removal effect of :microorganisms in using drycleaning solvent repeatedly 3) to investigate the kinds of microorganism living in textiles. The re, ;ultras of tai, ; study were as follows; 1) less microorganisms remains in perchloroethylen than in petroleum solvent. The most microorganisms was isolated at the beginning stage during the drycleaning. 2) In fresh drycleaning solvents, Pseudomonas aeruginosa ATTIC 27853, taphylococcsu atreus ATTIC 6538. and Candida albicans 10529 were killed immediately, while in case of pesters solvents used for 6 month-drycleaning, Pseudomonas Aeruginosa ATTIC 27853 were survived a lot of still in 17 days. 3) On the kind of bacteria in textile goods, Pseudomonas acidovorans and Ewsipelothrix rhusiopathiae are isolated. a genus Rhodetorula is observed through microscope. On the kind of fungi in textile goods, genus Penicillins and genus Apergillus are found through microscope, genus Caddie and genus Trichophyton are found with shapes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.483-487
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• 1991

The utilization of ozone as a disinfectant for removing poultry meat microorganisms and then cleaning the poultry rinse water was investigated. When microbial suspensions were treated with ozone at 2, 500ppm/min for 40min, microorganisms were not detectable perfectly. The bacteriocidal effect of ozone by temperature was enhanced greater at 7$^{\circ}C$ than $25^{\circ}C$. All poultry meat microorganisms were killed by ozone treatment at 1, 530ppm for 50min. The pathogenic bacteria such as Salmonella sp. were more vulnerable and not detected by ozone treatment for 20min. Ozonation of the suspension for 20min and 50min increased light transmission at 500nm to 58% and 145%, respectively. The order of COD removal was ozone treatment(21%), coagulant((Al)2SO4) treatment(41%), ozone treatment after coagulant treatment(54%).

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.41-48
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• 2000

Bacteroides fragilis and Escherichia coli, normal colonic inhabitants, are the most frequently isolated bacteria in infected tissues, particularly in intraabdominal abscesses. This study was designed to determine whether enteric bacteria may alter the B. fragilis-induced expression of pro inflammatory cytokines in mouse peritoneal tissue (MPT). After C57BL/6 mice were inoculated with abscess-forming mixture containing B. fragilis in the presence or absence of E. coli, RNA was extracted from MPT. Expression of interleukin (IL)-$1{\alpha}$ and tumor necrosis factor $(TNF){\alpha}$ mRNA was assessed using RT-PCR and standard RNA. Each cytokine protein was also measured by ELISA. The co-inoculation of E. coli into mouse peritoneal cavity advanced the onset of abscess development by B. fragilis infection. When mouse was co-infected with E. coli and B. fragilis intraperitoneally, there was a synergistic increase in the expression of IL-$1{\alpha}$ and $TNF{\alpha}$ mRNA in MPT and this was paralleled by increased cytokine protein secretion. Mixed inoculation of heat-killed E. coli and B. fragilis did not cause a synergistic increase in those cytokine mRNA expression. These results suggest that enteric bacteria may significantly affect proinflammatory cytokine signal produced by host peritoneal cavity in response to B. fragilis infection.

• Journal of Soil and Groundwater Environment
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• v.20 no.3
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• pp.25-33
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• 2015

In this study, Fe₃O₄-ACCS-Ag nanoparticles (NPs) were successfully synthesized using silica extracted from corn cob ash. The synthesized Fe₃O₄-ACCS-Ag NPs were characterized using X-ray diffraction (XRD), scanning electron microscopyenergy dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM) and fourier transform infrared spectroscopy (FTIR). In addition, the potential application of Fe₃O₄-ACCS-Ag NPs as an antibacterial material in water disinfection was investigated using Escherichia coli ATCC 8739 as model bacteria. The antibacterial activity of synthesized composite material showed 99.9% antibacterial effect within 20 min for the tested bacteria. From this experiment, the synthesized Fe₃O₄-ACCS-Ag nanocomposites also hold magnetic properties and could be easily recovered from the water solution for its reuse. The reused nanocomposites presented the decreasing antibacterial efficiencies with the reuse cycle but the composite used three times still killed 90% of bacteria in 20 min.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.6-10
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• 2015

Photodynamic therapy (PDT) apply photosensitizers and light. The purpose of this study was to evaluate the in vitro efficacy of PDT using blue LED (light emitting diode) with photofrin and radachlorin for Propionibacterium acnes. The colony forming units method was used to assess the antibacterial activity. Suspension (1 mL) containing P. acnes at $1{\times}10^5CFU/mL$ were prepared and then 2 fold serial diluted to $12.5{\mu}g/mL$ from $50{\mu}g/mL$ concentration of photofrin and radachlorin. After 60 minutes incubation, light was irradiated for 10 to 30 minutes using the following light source of wavelength 460 nm, each energy density 36, 72 and $108J/cm^2$. Bacterial growth was evaluated after 72 hours incubation in a Phenylethanol Blood Agar (PEBA) culture. In addition, flow cytometric analysis were performed to measure the live cell after PDT. Also transmission electron microscopy (TEM) was employed to evaluate the effect of pathogens by PDT. The PDT Group was perfectly killed to all kind of photosensitizers dose of $12.5{\mu}g/mL$ with irradiation of 10 minutes. Also other Groups were killed to all kind of photosensitizers dose of $6.25{\mu}g/mL$ with irradiation time of 20 and 30 minutes. The flow cytometry showed a lower number of viable bacteria in the PDT group compared to the control group. The images of the TEM results were showed in cytoplasmic membrane damage and partially deformed to cell morphologies. These results suggest that radachlorin and photofrin combine blue LED PDT can be effectively treated when was proved treatment for acnes therapy.

• Carbon letters
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• v.8 no.3
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• pp.184-190
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• 2007

Carbon Nano Tubes could be either metallic or semi-conducting in nature, depending on their diameter. Its photocatalytic behavior has given an impetus to use it as an anti-microbial agent. More than 95% Escherichia coli and Staphylococcus aureus bacteria got killed when exposed to Carbon Nano Tubes for 30 minutes in presence of sunlight. Carbon Nano Tubes are supposed to have smooth surface on to which it accumulates positive charges when exposed to light. The surface that is non illuminated has negative charge. At the cellular level microorganisms produce negative charges on the cell membrane, Therefore damaging effect of multi walled carbon nano tubes (exposed to light) on the microorganisms is possible. In this paper, photo catalytic killing of microbes by multi walled carbon nano tubes is reported. Killing was due to damage in the cell membrane, as seen in SEM micrographs. Moreover biochemical analysis of membrane as well as total cellular proteins by SDS PAGE showed that there was denaturation of membrane proteins as well as total proteins of both the microbes studied. The killed microbes that showed a decrease in number of protein bands (i.e. due to breaking down of proteins) also showed an increase in level of free amino acids in microbes. This further confirmed that proteins got denatured or broken down into shorter units of amino acids. Increased level of free amino acids was recorded in both the microbes treated with multi walled carbon nano tubes and sunlight.