• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.669-671
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• 2000

Antimicrobial cationic peptides have attracted increasing research and clinical interest as a natural antibiotics due to their broad spectrum of antimicrobial activites and the rapid development of multidrug-resistant pathogenic microorganisms. In this study, first, we synthesized artificial fusion partner and cationic peptide genes (lactoferricin, magainin, protegrin-1, and indolicidin). Second, we constructed recombinant expression vectors and then transformed Pichia pastoris. Finally, expressed cationic peptides were purified and tested for their antimicrobial activites. Antimicrobial activity has been tested upon the appearance of clearing zone on the plate with the lawn of gram negative E.coli XL- I blue and garm positive Staphylococcus aureus. Protegrin-1 and Indolicidin have apparant activity of cationic peotides. This fusion technique may lead to a general and suitable tool for production of pure antimicrobial cationic peptides in Pichia pastoris.

• 대한치과의사협회지
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• 제48권2호
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• pp.113-118
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• 2010

Titanium and titanium alloys are the most common materials used for dental and biomedical implants, owing to their biocompatibility and favourable mechanical properties. However infection of the region surrounding a dental implant by pathogenic microorganisms is a significant factor in implant failure. Prevention and control of microbial colonization of implant surfaces is considerable interest to the biomedical community. One important strategy is to render the implant surface antibacterial by impeding the formation of biofilm. A number of approaches have been proposed for this purpose. Therefore, we reviewed the researches of antibacterial coatings on titanium implants in this articles.

• 한국식품영양과학회지
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• 제28권5호
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• pp.1003-1009
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• 1999

For the isolation of probiotics which may be used for the human beings and animals, we have screened the microorganisms from chicken intestines which have acid and bile tolerance and the growth inhibition of pathogenic E. coli and Salmonella typhimurium. Among them, a strain which was identified as Lactobacillus salivarius had around 66% of survival after 2h incubation in the artificial gastric juice and 9% of survival after 24h incubation in the presence of 0.3% bile salts, and showed complete inhibition against both path ogenic E. coli and Salmonella typhimurium after 24 h coincubation. Its storage stability after lyophilization could be improved by adding polyvinylpyrrolidone.

• 한국유체기계학회 논문집
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• 제17권6호
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• pp.44-51
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• 2014

The disinfection method using UV has emerged as photodissociation in water disinfection. In order to predict performance for UV disinfection, CFD analysis was performed due to saving cost. Most CFD studies of UV reactor have used particle tracking method. However it demands additional analysis time, computing resource and phase besides working fluid. In this paper, pathogenic microorganisms' route is assumed to streamline of fluid to save computing time. the computational results are in good agreement with experimental results. The results of streamline method are compared with the particle tracking method. In conclusion, the effectiveness of streamline method for UV disinfection are confirmed.

• 한국지역사회생활과학회지
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• 제21권1호
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• pp.13-18
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• 2010

This study was performed to investigate the antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens. The growth inhibitory effects of the extract at a concentration of 250, 500, 1,000 or 2,000 mg/L on food poisoning microorganism were determined against Salmonella typhimurium, Listeria monocytogenes, Yersinia enterocolitica, Escherichia coli O157:H7 and Staphylococcus aureus. The microorganisms growth was not affected by the extract at the concentration up to 250 mg/L, but was significantly (p<0.05) inhibited by the extract at a concentration higher than 1,000 mg/L. The extract of Euphorbia humifusa had strong antimicrobial activity against all test strains at a concentration of 2,000 mg/L. The results in the present study demonstrate antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens, suggesting that Euphorbia humifusa could be an effective natural antibacterial agent in food.

• 생약학회지
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• 제39권3호
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• pp.246-248
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• 2008

Six prenylated xanthones, cudraxanthone B (1), isocudraxanthone K (2), cudraxanthone H (3), cudratricusxanthone A (4), cudraxanthone L (5) and macluraxanthone B (6), have been isolated from the MeOH extract of Cudrania tricuspidata root barks. The evaluation for antibacterial effect of compounds 1-6 against the pathogenic microorganisms concerning with public health or zoonosis was conducted. Of these, compound 4 showed significant antibacterial effect in disk diffusion method.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.60-60
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• 2002

• Journal of Dairy Science and Biotechnology
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• 제27권1호
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• pp.37-43
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• 2009

The mammalian immune system comprises a complex array of cells and molecules that interact to provide protection from pathogenic microorganisms. The beneficial role played by lactic acid bacteria and milk-derived peptides in humans, including their effect on the immune system, has been extensively reported. Lactic acid bacteria and milk-derived peptides, which are present in dairy products, are frequently used as nutraceuticals to improve some biological functions in the host. Activation of the systemic and secretory immune response by lactic acid bacteria and milk-derived peptides requires many complex interactions among the various constituents of the intestinal ecosystem. Thus, the aim of this review was to examine in detail the immunological potential of lactic acid bacteria and milk-derived peptides.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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• pp.582.1-582
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• 2001

IL-6 and IL-10 are known to be inflammatory cytokines that mediate host response to invading microorganisms or pathogenic antigen. But the roles of these cytokines in pulpal inflammation are not well established. The objective of this study was to investigate the concentrations and the roles of IL-6 and IL-10 in the pulpal inflammation associated with gram-negative bacteria, P. nigrescens. We exposed the pulps of rat mandibular incisors and inserted sterile cotton in control groups and inoculated P. nigrescens in experimental groups.(omitted)

• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.93-98
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• 2009

The thermophilic aerobic digestion (TAD) process is recognized as an effective method for rapid waste activated sludge (WAS) degradation and the deactivation of pathogenic microorganisms. Yet, high energy costs due to heating and aeration have limited the commercialization of economical TAD processes. Previous research on autothermal thermophilic aerobic digestion (ATAD) has already reduced the heating cost. However, only a few studies have focused on reducing the aeration cost. Therefore, this study applied a two-step aeration control strategy to a fill-and-draw mode semicontinuous TAD process. The NADH-dependent fluorescence was monitored throughout the TAD experiment, and the aeration rate shifted according to the fluorescence intensity. As a result, the simple two-step aeration control operation achieved a 20.3% reduction in the total aeration, while maintaining an effective and stable operation. It is also expected that more savings can be achieved with a further reduction of the lower aeration rate or multisegmentation of the aeration rate.