• 한국미생물·생명공학회지
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• 제39권1호
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• pp.1-8
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• 2011

The antimicrobial effects of silver (Ag) ion or salts are well known. Recently, silver nanoparticle is attracting an interest in a wide variety of fields since it has been known to be safe and effective as an antimicrobial agent against a broad spectrum of microorganisms. Although silver nanoparticle has been applied to various kinds of products owing to its potent antimicrobial activity, the effects of silver nanoparticle on microorganisms and antimicrobial mechanism have not been revealed clearly. In this paper, we summarized the characteristics, antimicrobial activities and mechanisms, cytotoxicity and applicability of silver nanoparticle.

• Environmental Engineering Research
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• 제13권3호
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• pp.136-140
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• 2008

$TiO_2$ photocatalyst has been known to exhibit a notable disinfecting activity against a broad spectrum of microorganisms. A lot of commercial $TiO_2$ photocatalyst products have been developed for antimicrobial purposes. However, a standard method has not yet been proposed for use in testing antimicrobial activity. In this study, we developed a $TiO_2$ photocatalytic adhesion test method with film as the standard testing method for the evaluation of antimicrobial activity. This method was devised by modifying the previous antimicrobial products test method, which has been widely used, and considering the characteristics of $TiO_2$ photocatalytic reaction. The apparatus for testing the antimicrobial activity was composed of a Black Light Blue (BLB) lamp as UV-A light source, a Petri dish as the cover material, and a polypropylene film as the adhesion film. The standard $TiO_2$ photocatalyst sample, Degussa P25 $TiO_2$ - coated glass, could only be used once. The optimal initial concentration of the microorganism, proper light intensity, and light irradiation time were determined to be $10^6$ CFU/mL, 1.0 mW/$cm^2$, and 3 hr, respectively, for testing and evaluating antimicrobial activity on the $TiO_2$ surface.

• 한국환경과학회지
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• 제11권1호
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• pp.33-40
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• 2002

An antimicrobial substance-producing microorganism was isolated from soil samples. Based of the taxonomic characteristics of its morphological, cultural, physiological properties and 16s rRNA sequence alignment, this microorganism was identified as Pseudomonas aeruginosa, and we named Pseudomonas aeruginosa EL-KM. The optimal culture condition for production of antimicrobial substance was 1% mannitol, 0.4% yeast extract, 0.5% Nacl, 0.2% $K_2SO_4$, 100$\mu$M $MgSO_4$.$7H_2O$, 10$\mu$M $CaCl_2$.$2H_2O$, 1$\mu$M $FeSO_4$.$7H_2O$, 1$\mu$M $MnSO_4$.$4-5H_2O$, initial pH 7 and 200 rpm at 3$0^{\circ}C$. The purification of the antimicrbial substance was performed by silica gel column chromatographys, and fraction with TLC $R_f$ 0.77 value represented good antimicrobial activity. The crude antimicrbial substance was stable within a pH range of 3-10 and temperature range of 4$^{\circ}C$-121$^{\circ}C$ autoclaving. This crude antibacterial substance acted as bacteriolytic agent against Vibrio cholerae non-Ol ATCC 25872, and also exhibited excellent properties, when the substance was demonstrated against many other gram-positive, gram-negative bacteria, yeast and fungi.

• 한국염색가공학회지
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• 제31권4호
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• pp.323-331
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• 2019

Sorghum is a rich source in phytochemicals, such as tannins, phenolic acids, anthocyanins, phytosterols and policosanols. Sorghum has been known to have antimicrobial, antiinflammatory, antioxidant properties. In this study, poly(vinyl alcohol)(PVA)-sorghum extract(SE) composite nanoweb was produced by electrospinning and its characteristics including bioactivities were investigated. The SE had antimicrobial and antiinflammatory activities as well as a reduced cytotoxicity. The PVA-SE nanoweb had a highly enhanced antimicrobial activity compared to PVA nanoweb. The amount of proinflammatory cytokine released from macrophages treated with the PVA-SE nanoweb was reduced. The PVA-SE nanoweb can be a potential candidate for medical and cosmeceutical materials providing antimicrobial and antiinflammatory activities with a low degree of cytotoxicity.

• 한국응용과학기술학회지
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• 제28권4호
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• pp.393-401
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• 2011

Natural Curcumin belongs to Zingiber Officinale Roscoe was known to possess natural odor, natural taste, natural color, and other pharmaceutical & chemical characteristics. Natural Curcumin extract was made to use ethanol as a solvent was to show a yellow color having state of solid powder and an active component. Natural Curcumin extract tested pharmaceutical & chemical experiment to dilute in curcumin 1%-water solution. Curcumin extract tested antimicrobial experiment using microbe, and tested dye experiment using fiber. Some conclusions in the result of characteristics experiment was obtained as follow. The result of antimicrobial experiment showed that the growth of staphylococcus aureus (ATCC-001) and aspergillus niger (ATCC-002) as microbes decreased according to passage of time. This phenomenon could know that Curcumin compoment showed influence to antimicrobial effect. Also, the result of dye experiment showed that cotton and sick with fiber dyeing dyed in direction of dark yellow color. This phenomenon could know that Curcumin extract showed influence to dyeing effect in observation of optical electron microscope(OEM.) The result of instrument analysis ascertained inorganic components of K(53.300ppm), Na(1.150ppm), Ca(0.711ppm), Ti(0.351ppm), Li(0.256ppm), Cu(0.233ppm) etcs from Curcumin component with ICP/OES, and ascertained organic components of propanoic acid(1.859), benzene(10.814), phenol(14.194) etcs from Curcumin component with GC/MSD.

• 한국식품조리과학회지
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• 제33권1호
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• pp.65-71
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• 2017

Purpose: This study was carried out to investigate the availability of raw Astragalus membranaceus as a food ingredient. Methods: Raw and dried A. membranaceus water extracts were used to examine the free radical scavenging activity, polyphenol and flavonoid contents, and antimicrobial activity. Also, the sensory characteristics of each water extracts were evaluated. Results: The free radical scavenging activity and total polyphenol and flavonoid contents of raw A. membranaceus extracts were higher than those of dried A. membranaceus extracts. The antimicrobial activities of raw and dried A. membranaceus extracts were examined against several food borne illness-causing microorganisms using the paper disc diffusion method. Inhibition zones were observed in Staphylococcus aureus subsp. aureus, Bacillus subtilis, Pseudomonas aeruglnosa, Salmonella enterica subsp. enterica, Escherichia coli and Bacillus cereus treated with raw extracts. Inhibition zones were observed in B. subtilis, P. aeruglnosa and S. enterica subsp. enterica treated with dried extracts. Raw A. membranaceus extracts had higher scores than dried extracts in sensory evaluation. Conclusion: Raw A. membranaceus was better in antioxidative, antimicrobial activities, and sensory characteristics than dried one.

• 생약학회지
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• 제27권4호
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• pp.378-382
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• 1996

We previously reported the morphological, physiochemical characteristics of Alismae Rhizoma. In this study, we examined the antimicrobial and antifungal activities of 85% ethanol and water extracts of Alismae Rhizoma using disc method. Ethanol extracts of Korean Alismae Rhizoma showed antimicrobial activity on B. subtilis and S. aureus on the concentration dependent manner, whereas, Chinese Alismae Rhizoma revealed antimicrobioal activity on E. coli and N. gonorrhoeae. The water solution(500 mg/ml) of each lyophilized powder of aqueous extracts didn't show any antimicrobial activity on B. subtilis, S. aureus and E. coli, on the contrary, they stimulated cell growth slightly. Ethanol extracts of Korean samples showed antifungal activity on A. niger, but not on C. albicans. Neither A. niger nor C. albicans were affected by Chineses samples.

• Journal of Microbiology and Biotechnology
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• 제28권3호
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• pp.381-390
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• 2018

We have previously derived a novel antimicrobial peptide, LPcin-YK3(YK3), based on lactophoricin and have successfully studied and reported on the relationship between its structure and function. In this study, antimicrobial peptides with improved antimicrobial activity, less cytotoxicity, and shorter length were devised and characterized on the basis of YK3, and named YK5, YK8, and YK11. The peptide design was based on a variety of knowledge, and a total of nine analog peptides consisted of one to three amino acid substitutions and C-terminal deletions. In detail, tryptophan substitution improved the membrane perturbation, lysine substitution increased the net charge, and excessive amphipathicity decreased. The analog peptides were examined for structural characteristics through spectroscopic analytical techniques, and antimicrobial susceptibility tests were used to confirm their activity and safety. We expect that these studies will provide a platform for systematic engineering of new antibiotic peptides and generate libraries of various antibiotic peptides.

• 한국식품영양과학회지
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• 제28권3호
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• pp.526-533
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• 1999

Two species of antimicrobial agent producing bacteria and one sensitive strain were isolated from soil. Those were identified as B. subtilis, B. licheniformis, and Curtobacterium sp. by morphological, biochemical, physiological and chemotaxonomic characteristics. These were designated as B. subtilis cx1, B. licheniformis cy2 and Curtobacterium sp. cf3, respectively. Antimicrobial agent produced by B. subtilis cx1 showed high antibacterial activity against gram positive bacteria including of B. subtilis, Curtobacterium sp., L. mesenteroids, Staphy. aureus, S. faecalis and even gram negative bacteria, P. aeruginosa. Antimicrobial agent from B. licheniformis cy2 showed slightly lower antimi crobial activity than that from B. subtilis cx1. These two strains showed maximum production of antimicrobial agents at 30oC for 9~21hr cultivation. Curtobacterium sp. cf3 showed more sensitive activity than a sensitive strain of B. subtilis ATCC 6633 which was same genus or species with the B. subtilis cx1 and B. subtilis cy2, when the antimicrobial agent producing strains, B. subtilis cx1 and B. subtilis cy2, were directly applied onto these sensitive lawns.

• Restorative Dentistry and Endodontics
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• 제39권4호
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• pp.241-252
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• 2014

The goal of endodontic treatment is the prevention and control of pulpal and periradicular infections. Calcium hydroxide ($Ca(OH)_2$) has been widely used in endodontics as an intracanal medicament to eliminate the remaining microorganisms after chemomechanical preparation. The purpose of this article is to review the antimicrobial properties of $Ca(OH)_2$ as an intracanal medicament in root canal treatment. The first part of this review details the characteristics of $Ca(OH)_2$ and summarizes the results of in vitro studies related to its antimicrobial effect. The antimicrobial effect of $Ca(OH)_2$ results from the release of hydroxyl ions when it comes into contact with aqueous fluids. $Ca(OH)_2$ has a wide range of antimicrobial effects against common endodontic pathogens, but is less effective against Enterococcus faecalis and Candida albicans. The addition of vehicles or other agents might contribute to the antimicrobial effect of $Ca(OH)_2$.