• Journal of Korean Society on Water Environment
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• v.36 no.2
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• pp.148-152
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• 2020

The quantitative accuracy of dry rehydratable film method was compared with the standard culture method to analyze the applicability of dry rehydratable film in the total aerobic bacteria test for water. The materials used in this study were 500 cases of water and were tested according to the Korean official test method for drinking water. The mean value of the total aerobic bacteria in plate count agar(PCA) and MC-Media Pad AC(MAC) were 2.6 ± 1.1 Log cfu/mL and 2.6 ± 1.2 Log cfu/mL. The p value and correlation coefficient(R²) were 0.933 and 0.9985 between the PCA and MAC, respectively, indicating no significant difference and very high correlation. According to the water types, the p value and R² were 0.887 and 0.9911 in the PCA and MAC. In the purified water, the p value was 0.973 and R² was 0.9934 in the PCA and MAC of other water. In each type of water, there were no significant differences between the PCA and MAC, and the correlation was very high. Thus, it is suggested that the MAC would be available for total aerobic bacteria test for water.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.995-1004
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• 2017

Culture-dependent methods, such as heterotrophic plate counting (HPC), are usually applied to evaluate the bacteriological quality of hemodialysis water. However, these methods cannot detect the uncultured or viable but non-culturable (VBNC) bacteria, both of which may be quantitatively predominant throughout the hemodialysis water treatment system. Therefore, propidium monoazide (PMA)-qPCR associated with HPC was used together to profile the distribution of the total viable bacteria in such a system. Moreover, high-throughput sequencing of 16S rRNA gene amplicons was utilized to analyze the microbial community structure and diversity. The HPC results indicated that the total bacterial counts conformed to the standards, yet the bacteria amounts were abruptly enhanced after carbon filter treatment. Nevertheless, the bacterial counts detected by PMA-qPCR, with the highest levels of $2.14{\times}10^7copies/100ml$ in softener water, were much higher than the corresponding HPC results, which demonstrated the occurrence of numerous uncultured or VBNC bacteria among the entire system before reverse osmosis (RO). In addition, the microbial community structure was very different and the diversity was enhanced after the carbon filter. Although the diversity was minimized after RO treatment, pathogens such as Escherichia could still be detected in the RO effluent. In general, both the amounts of bacteria and the complexity of microbial community in the hemodialysis water treatment system revealed by molecular approaches were much higher than by traditional method. These results suggested the higher health risk potential for hemodialysis patients from the up-to-standard water. The treatment process could also be optimized, based on the results of this study.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.98-112
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• 1996

Tho purpose of this study was to investigate hygienic and comfortable properties of socks. Materials are nine summer socks either frequently being worn or new products recently introduced to market. Three female and three male adults participated in this study. Through wearing experiment, the numbers of microbes on foot and sock were counted and subjective sensation was measured. The microbes were isolated and identified based on growth physiological characteristics. Nine different socks had smaller number of bacteria of sock than that of foot. The number of bacteria of sock was significantly related with that of foot in cotton socks, in piled cotton socks, in mesh cotton socks, in cotton+ nylon+ linen blended socks, in nylon socks. Total number of bacteria of tv cut finished socks was most small and total number of bacteria was increased in the order of ultra fresh finished socks, untreated cotton socks, nylon socks, cotton + nylon+ linen blended socks, mesh cotton socks, polyester+ nylcn+ linen blended socks, piled cotton socks, cotton socks. Total number of bacteria of cotton socks and piled cotton socks were significantly different from that of uv cut finished socks. Finished socks and .jocks has high air permeability had significantly small number of bacteria. Comfortable sensation in nylon socks and polyester+nylon+linen socks was significantly uncomfortable. The way socks finished and air permeability of .jocks affected theirs hygienic property, while fiber type of them affected comfortablene, is. Bacteria identified were Staphylo coccus aureus, S. au rice larir, S. cahn ii, S. ep ids midis, S. haemo Iyticus, S. h am in 2's. S.fapraphyticus, S. warnery, 1 cinetobater calcoaceticus bio. anitratus, p.reudomonas mendocina, p. paucimobilis, Flavimonas Q ryzihabitans (CDC Group VE-2), and Xanthomanas maltophina. Fungi isolated were Spicaria sp., Thrichoderma sp., Fusarium sp., Aspergillus sp., Epicoccum sp., Cladosporium sp., and Penicillium sp..

• Journal of Korean society of Dental Hygiene
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• v.17 no.1
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• pp.13-25
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• 2017

Objectives: The purpose of this study was to compare colony forming unit (CFU) method and multiplex real-time polymerase chain reaction (MRT-PCR) method for accurate quantitative analysis of bacteria. Methods: We compared the CFU method and the MRT-PCR method, which are still used in Korea, for Prevotella intermedius (P. intermedius), a periodontal disease pathogen selected by MRT-PCR, and Streptococcus mutans (S. mutans), a dental caries causative organism. The subjects of this study were 30 patients who visited the C dental hospital. Results: Total microorganisms in MRT-PCR method were significantly higher in both types of bacteria (p<0.05), since DNA of dead bacteria was also analyzed. This was because the periodontal dise(-) anaerobes, and even dead bacteria contain large amounts of toxic substances called LPS in the extracellular membrane, and fimbriae and pili, which are motility structures, still remain as a strong toxic substance in periodontal tissue. Conclusions: Therefore, in terms of the total amount of bacteria found, the MRT-PCR method will be a useful technique for searching all the bacteria in the oral cavity including live bacteria, as well as sterilization.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.80-84
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• 2001

Vertical and temporal variations of active and total bacterial abundance were monthly estimated in Lake Soyang from April 1999 to January 2000. The number of total and respiring bacteria was determined directly under microscope by AODC and CTC methods, respectively. The number of total and active bacteria varied from $2.1{\times}10^5 to 3.1{\times}10^6 $,$cells{\cdot}ml^{-1}$ and $1.8{\times}10^4 to 8.0{\times}10^5 $,$cells{\cdot}ml^{-1}$, respectively. The proportions of respiring bacteria to total cell ranged from 3.7 to 44.2% : The proportions was the highest in November 1999 and the lowest in December 2000. The specific activity of${\beta}$-glucosidase divided by total bacteria was$1.6{\times}10^5\;amol{\cdot}cell^{-1}{\cdot}hr^{-1}$in August and$1.4{\times}10^5\;amol{\times}cell^{-1}{\times}hr^{-1}$in September while the specific activity divided by CTC active bacteria was about$3.6{\times}10^5\;amol{\cdot}cell^{-1}{\cdot}hr^{-1},\;24.0{\times}10^5\;amol{cdot}cell^{-1}{cdot}hr^{-1}$. The specific activity of active bacteria in September was 6.7 times higher than that of August. By these data of active bacteria, the new information of aquatic ecosystem was unveiled.

• Journal of Environmental Health Sciences
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• v.38 no.2
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• pp.151-158
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• 2012

Objectives: Bioaerosols released by treating organic-waste resources cause a variety of environmental and hygiene problems. The objective of this study was to investigate the distribution characteristics of the airborne bacteria emitted from a pig manure composting plant, a principal site for organic-waste resource facilities. Methods: Three types of pig manure composting plant were selected based on fermentation mode: screw type, rotary type and natural-dry type. Each site was visited and investigated on a monthly basis between September 2009 and August 2010. A total of 36 air samplings were obtained from the pig manure composting plants. The air sampling equipment was a six-stage cascade impactor. Quantification and qualification of airborne bacteria in the air samples was performed by agar culture method and identification technique, respectively. Results: The mean concentrations of airborne bacteria in pig manure composting plant were 7,032 (${\pm}1,496$) CFU $m^{-3}$ for screw type, 3,309 (${\pm}1,320$) CFU $m^{-3}$ for rotary type, and 5,580 (${\pm}1,106$) CFU $m^{-3}$ for natural dry type. The screw type pig manure composting plant showed the highest concentration of airborne bacteria, followed by the natural dry type and the rotary type. The ratio of respirable to total airborne bacteria was approximately 40-60%. The predominant genera of airborne bacteria identified were Micrococcus spp., Staphylococcus spp. and Escherichia spp. Conclusion: Monthly levels of airborne bacteria were highest in August and lowest in November regardless of fermentation mode. There was no significant correlation relationship between airborne bacteria and environmental factors such as temperature, relative humidity and particulate matters in pig manure composting plants.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.366-370
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• 1992

Sediment samples were collected from the stations 0101-0921 located between N $32^{\circ}$30'~$34^{\circ}$30' and E $123^{\circ}$30'-$128^{\circ}$30' during July 31-August lO. 1988. The distributions of total heterotrophic bacteria, freshwater bacteria and hydrocarbon degrading bacteria were studied. Each bacterial distribution was in the range of $3{\times}10^{5}~9.2{\times}10^{6}CFU/cm^{3}$sediment, $3{\times}10^{3}~2.1{\times}10^{6}CFU/cm^{3}$ sediment and $2{\times}10^{4}~6.2{\times}10^{6}CFU/cm^{3}$ sediment. respectively. The percent of hydrocarbon degrading bacteria against total heterotrophic bacteria was 0.7-73,2 % which was much higher than other marine sediments reported. These values were statistically analyzed with the percent of freshwater bacteria against total heterotrophic bacteria. These two parameters were well correlated with the correlation coefficient r= 0.60058 (n=34) and P=0.OOO2. This means that the distributions of hydrocarbon degrading bacteria and freshwater bacteria in the research area were affected together by the fresh water discharge into the sea environment. Therefore it can be concluded that the distribution of hydrocarbon degrading bacteria in the sediment of South Sea was affected by petroleum hydrocarbon input from terrestrial region through rivers.

• Herbal Formula Science
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• v.19 no.2
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• pp.83-92
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• 2011

Objectives : This study was carried out to moniter microbial flora on freeze-dried herbal powder and identify isolated bacteria. Methods : We measured the total number of bacteria and fungi in 29 herbal powder which had made according to the guideline of KFDA. For the identification, we observed microscopic properties and carried out polymerase chain reaction(PCR). The purified DNA was analyzed by DNA sequencer. Results : Among the 29 herbal powders, the fungi were detected only one sample as unacceptable range of total aerobic bacteria. Isolated bacteria were identified as Bacillus cereus, B. subtilis, B. megaterium, B. licheniformis, Erwinia tasmaniensis, E. amylovora, and Pantoea agglomerans by 16S rDNA analysis. E. tasmaniensis was observed 20 herbal samples. Conclusions : According to above results, further studies for the effective sterilization of low herbal materials should be needed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.6
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• pp.324-331
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• 2019

Objectives: This study investigated the types and antibiotic sensitivity of bacteria in odontogenic abscesses. Materials and Methods: Pus specimens from 1,772 patients were collected from affected areas during incision and drainage, and bacterial cultures and antibiotic sensitivity tests were performed. The number of antibiotic-resistant bacteria was analyzed relative to the total number of bacteria that were tested for antibiotic susceptibility. Results: Bacterial cultures from 1,772 patients showed a total of 2,489 bacterial species, 2,101 gram-positive and 388 gram-negative. For penicillin G susceptibility tests, 2 out of 31 Staphylococcus aureus strains tested showed sensitivity and 29 showed resistance. For ampicillin susceptibility tests, all 11 S. aureus strains tested showed resistance. In ampicillin susceptibility tests, 46 out of 50 Klebsiella pneumoniae subsp. pneumoniae strains tested showed resistance. Conclusion: When treating odontogenic maxillofacial abscesses, it is appropriate to use antibiotics other than penicillin G and ampicillin as the first-line treatment.