• Applied Chemistry for Engineering
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• v.19 no.1
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• pp.122-128
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• 2008

We evaluated the relationship between the multiplication of heterotrophic microorganisms and physicochemical factors in the final discharged sewage water from J municipal waste water treatment plants. Dissolved organic carbon (DOC) was the most crucial factor influencing multiplication of heterotrophic plate counts (HPC) among the water quality variables selected. Degrading bacteria, such as proteolytic bacteria, lipholytic bacteria, starch degrading bacteria, cellulolytic bacteria, and pectinolytic bacteria, were monitored to understand the condition of nutrients in finished sewage effluent. The percentages of lipid and protein combined occupied 81% in finished sewage water. The multiplication of HPC showed the highest value in August. The formation of trihalomethane (THM) was low in the finished discharge water during chlorine disinfection, which was $71{\mu}/L$ (which was less than $100{\mu}/L$- the standard of drinking water quality) with 10 mg/L of chlorine during 15 min.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.273-278
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• 2005

This study was performed to investigate the characteristics of distribution for airborne bio aerosol in 11 public facilities in Seoul from June to July. The collected samples are total suspended bacteria in indoor and outdoor Anderson six stage air sampler by the IAQ standard method of Ministry of Environment in Korea. The concentration of total suspended bacteria in the theater higher than IAQ standards. As the results of the survey, the most high indoor air mean concentration of bacteria $1273CFU/m^3$ was theater and the most high outdoor air mean concentration of bacteria $^229 CFU/m3$was Kindergarten. The mean concentration of bacteria in the theater was higher than the IAQ standards established by the Ministry of Environment, Republic of Korea. Moreover, this study was for investigation a part of indoor air pollution condition in public facilities. It means that this study can't represent fDr all of public facilities. Therefore, we suggest that long and middle term country plan for management of IAQ should be established through long-term and continuous investigation of IAQ condition. Also above consideration in mind, it is suggest that the research for source contribution of the results on these need further study.

• Journal of Aquaculture
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• v.16 no.2
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• pp.118-123
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• 2003

This study was conducted to investigate the disinfection effects of chlorine dioxide ($ClO_2$) on 4 fish pathogenic bacteria (Vibrio anguillarum, Edwardsiella tarda, Streptococcus sp. and Staphylococcus sp.) isolated from infected olive flounders. The bacteria were exposed to different concentrations of ClO$_2$ (0.129, 0.246 and 0.455 ppm) and response times (0.5, 1, 3, 5 and 10 min), and then were incubated for 12 hr. The effective disinfection concentrations of $ClO_2$ against experimental bacteria by $ClO_2$ for 0.5 min were observed with 0.455 ppm for Staphylococcus sp., 0.246 ppm for V. anguillarum and E. tarda, and 0.129 ppm for Streptococcus sp., respectively. The duration of exposure at low concentration of $ClO_2$ increased for the disinfectant ability to experimental bacteria.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.31-37
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• 2015

This study was conducted to investigate the bactericidal activity of electrolyzed water (EW) against coliform bacteria on Undaria pinnatifida (UP). The UP was washed with 15% EW, tap water (TW), and distilled water in the following order: 15% EW for 5 and 10 min (1st to 3rd washing process), TW for 1 min, and distilled water for 10 min (3rd to 5th washing process). The washing processes using 15% EW and distilled water occurred a total of 6 times. The number of viable cells, coliform bacteria, and molds in the untreated sample were in the range of 10¹ to 10³ CFU/g. In the case of the UP with 15% EW for 5 min sample, the viable cell counts were reduced by 1-2 log cycles as compared with the untreated sample. The coliform bacteria were not detected except after the 1st EW washing process. Mold counts were not detected in all treatments. In the UP with 15% EW for 10 min sample, the viable cells, coliform bacteria, and mold counts were not detected. In color, there were no significant differences among samples. In sensory evaluation, the UP treated with 15% EW for 10 min (first washing process) got higher scores for color, aroma, and taste than others. These results suggest that the treatment of 15% EW for 10 min is the most effective way to reduce coliform bacteria of the UP.

• Safety and Health at Work
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• v.11 no.4
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• pp.517-525
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• 2020

Background: The study was planned to show the status of indoor microorganisms and the status of the reduction device in the military dog clinic. Methods: Airborne microbes were analyzed according to the number of daily patient canines. For identification of bacteria, sampled bacteria was identified using VITEK^®2 and molecular method. The status of indoor microorganisms according to the operation of the ventilation system was analyzed. Results: Airborne bacteria and fungi concentrations were 1000.6 ± 800.7 CFU/m³ and 324.7 ± 245.8 CFU/m³. In the analysis using automated identification system, based on fluorescence biochemical test, VITEK^®2, mainly human pathogenic bacteria were identified. The three most frequently isolated genera were Kocuria (26.6%), Staphylococcus (24.48%), and Granulicatella (12.7%). The results analyzed by molecular method were detected in the order of Kocuria (22.6%), followed by Macrococcus (18.1%), Glutamicibacter (11.1%), and so on. When the ventilation system was operated appropriately, the airborne bacteria and fungi level were significantly decreased. Conclusion: Airborne bacteria in the clinic tend to increase with the number of canines. Human pathogenic bacteria were mainly detected in VITEK^®2, and relatively various bacteria were detected in molecular analysis. A decrease in the level of bacteria and fungi was observed with proper operation of the ventilation system.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.6
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• pp.395-399
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• 2000

Five different freeze-dried recombinant bioluminescent bacteria were used for the detection of cellular stresses caused by endocrine disrupting chemicals. These strains were DPD2794 (recA::luxCDABE), which is sensitive to DNA damage, DPD2540 (fabA::luxCDABE), sensitive to cellular membrane damage, DPD2511 (katG::luxCDABE), sensitive to oxidative damage, and TV1061 (grpE::luxCDABE), sensitive to protein damage. GC2, which emits bioluminescence constitutively, was also used in this study. The toxicity of several chemicals was measured using GC2. Damage caused by known endocrine disrupting chemicals, such as nonyl phenol, bisphenol A, and styrene, was detected and classified according to toxicity mode, while others, such as phathalate and DDT, were not detected with the bacteria. These results suggest that endocrine disrupting chemicals are toxic in bacteria, and do not act via an estrogenic effect, and that toxicity monitoring and classification of some endocrine disrupting chemicals may be possible in the field using these freeze-dried recombinant bioluminescent bacteria.

• Journal of Environmental Health Sciences
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• v.33 no.2 s.95
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• pp.104-114
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• 2007

This study evaluated the airborne concentrations of bacteria, Gram-negative bacteria, and fungi in waiting rooms, wards, and outdoors, according to time and particle size between October 17 and November 28, 2003. The geometric mean number of airborne bacteria was highest in the morning. The more people there were, the higher was the total bacteria concentration. The concentration of fungi was also highest in the morning. Temperature and relative humidity affected the concentrations of fungi significantly (p<0.05). This study found relationships between microorganism concentrations and (actors such as time, place, temperature, humidity, ventilation, and number of people. Therefore, to manage the pollution resulting from airborne microorganisms, each time, place, and environmental factor should be examined periodically, and the number, size, and movement of airborne microorganisms should be evaluated.

• Toxicological Research
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• v.29 no.2
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• pp.129-135
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• 2013

Salmonella is one of the major pathogenic bacteria that cause food poisoning. This study investigated whether heat-killed as well as live Lactobacillus protects host animal against Salmonella infection. Live and heat-killed Lactobacillusacidophilus was administered orally to Sprague-Dawley rats for 2 weeks before the rats were inoculated with Salmonella. Rise in body temperature was moderate in the group that was treated with heat-killed bacteria as compared to the Salmonella control group. The mean amount of feed intake and water consumption of each rat in the heat-killed bacteria group were nearly normal. The number of fecal Salmonellae was comparable between the live and the heat-killed L. acidophilus groups. This finding shows that L. acidophilus facilitates the excretion of Salmonella. Moreover, the levels of pro inflammatory cytokines, including tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 beta, in the heat-killed L. acidophilus group were significantly lower when compared to the levels in the Salmonella control group. These results indicate that nonviable lactic acid bacteria also could play an important role in preventing infections by enteric pathogens such as Salmonella.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.8
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• pp.1268-1272
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• 2004

The 70% ethanol extract from cactus Chounnyouncho (Opuntia humifusa) was fractionated subsequently by hexan, chloroform, ethyl acetate, buthanol and water. The ethyl acetate fraction exhibited strong antimicrobial activities by paper disk diffusion method on the five strains of food born bacteria Bacillus subtilis, Staphylococcus aureus subsp. aureus, Escherichia coli, Salmonella typhimurium and Pseudomonas fluorescens. It has a heat resistance to show inhibitory effect after heat treatment at 11$0^{\circ}C$ for 1 hr. The ethyl acetate fraction showed almost perfect growth inhibition at over 700 ppm on the tested strains.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.9-14
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• 2003

When ginsenosides Rbl, Rb2, and Rc were anaerobically incubated with commercial and human intestinal lactic acid bacteria, most commercial lactic acid bacteria did not metabolize these ginsenosides to compound K. However, lactic acid bacteria, B. minimum KK-1, Bifidobacterium cholerium KK-2, and B. cuniculi K-513, isolated from human intestinal microflora transformed these ginsensosides to compound K. When the bacterial mixtures of commercial lactic acid bacteria were incubated with these ginsenosides, these compounds were not transfformed to compound K. However, when Bzfidobacterium KK-1 and KX-2 were miked, these ginsenosides were synergistically transformed to compound K. When water extract of ginseng was incubated with these mixed bifidobacteria, compound K was potently produced. Therefore, it is suggested that, if ginseng with these mixed bifidobacteria is fermented, compound K-enforced ginseng materials could be produced that show cytotoxicity against tumor cell lines.