• 한국염색가공학회지
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• 제23권2호
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• pp.69-75
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• 2011

A pre-treatment process has been developed for natural dyeing of wool by which the dyed materials have been imparted antimicrobial efficacy against both gram-positive and gram-negative bacteria durable up to 20 washes. In this process, wool fabrics were treated with citric acid under oxidizing condition prior to dyeing. The treated fabrics were then dyed with four different types of natural dye powders obtained from leaves of silver oak, wattle, tanner's senna and flame of forest. All the natural dyes produced yellowish brown colour on wool fabrics. The washing and light fastness properties of the fabrics subjected to pre-treatment were one grade higher compared to those of the dyed fabrics without pre-treatment. The pre-treated wool fabrics showed antimicrobial efficacy against both gram-positive bacteria (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). The fabrics dyed without pre-treatment showed antimicrobial efficacy against gram-positive bacteria (Staphylococcus aureus) only. The durability of antimicrobial efficacy was higher in pre-treated and dyed wool fabrics compared to the dyed fabrics without pre-treatment.

• 한국임상수의학회지
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• 제34권6호
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• pp.425-428
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• 2017

Silver nanoparticles have marked antimicrobial effects on several pathogens and have been used to control bacterial growth in humans. In the present study, we evaluated the antimicrobial efficacy of silver nanoparticles against the common causative pathogens of canine otitis external through counting of colony forming units. Silver nanoparticles showed significant dose-dependent antimicrobial effects on pathogens. In addition, we conducted antimicrobial susceptibility tests and compared the antimicrobial efficacy of silver nanoparticles. Microorganisms with a high resistance to antibiotics were also resistant silver nanoparticle with low concentration ($5{\mu}g/mL$). However, in high concentration ($15{\mu}g/mL$), almost 100% reduction in the number of CFUs of these pathogens was observed.

• 대한수의학회지
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• 제61권2호
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• pp.16.1-16.6
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• 2021

Pseudomonas aeruginosa is one of the most common pathogenic species associated with canine otitis externa (OE). Their resilience is achieved by forming a biofilm, which allows these bacteria to evade even the harshest of treatments. This study evaluated the in vitro synergistic efficacy of N-acetylcysteine (NAC) with different antimicrobial agents against P. aeruginosa isolated from dogs with OE to develop an effective treatment against P. aeruginosa. The antimicrobial activity was evaluated by the minimum inhibitory concentration test using the microdilution method. The efficacy of antibiofilm formation was evaluated using a crystal violet stain method. The treatment solutions included NAC alone, and in synergy with enrofloxacin, polymyxin B, and gentamicin. NAC alone exhibited antimicrobial and antibiofilm abilities. On the other hand, the combination of NAC and the antibiotics did not show any significant synergistic effects against P. aeruginosa.

• 동의생리병리학회지
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• 제17권6호
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• pp.1427-1432
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• 2003

This study was carried out to investigate the antimicrobial and anticancer effects of Galla Rhois (GR) on pathogens isolated from oral and KB human oral epidermoid carcinoma cells. Their antimicrobial activities were tested against Streptococcus mutans (S. mutans), Staphylococcus aureus (S. aureus), Enterobacter aerogenes (E. aerogenes), Escherichia coli (E. coil) and Candida albicans (C. albicans). GR powder has the antimicrobial activity against C. albicans, S. mutans and S. aureus. The extracts of water and ethanol have the antimicrobial activity against S. sureus and C. albicans. The water extract showed inhibitory activity against the growth and pH of above mentioned reference microorganisms. The water extract of GR declined cell viability in a dose dependent manner. DNA flow cytometric analysis showed that population of sub-G/sub 0//G₁, phase of cell cycle was increased by GR extract treatment in a dose dependent manner. Western blot analysis revealed that Caspase-3 was reduced by GR extract treatment. These result suggested that GR has the effect of antimicrobial on pathogens isolated from oral, and also, has anticancer effect that associated with the induction of apoptosis in a dose dependent manner in KB human oral epidermoid carcinoma cells. It may be GR-induced apoptosis was mediated via activation of Caspase-3.

• Mycobiology
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• 제45권3호
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• pp.178-183
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• 2017

Diabetes mellitus is a chronic disorder which affects millions of population worldwide. Global estimates published in 2010 reported the world diabetic prevalence as 6.4%, affecting 285 million adults. Foot ulceration and wound infection are major forms of disabilities arising from diabetic diseases. This study was aimed to develop a natural antimicrobial finishing on medical grade textile that meets American Association of Textiles Chemists and Colorists (AATCC) standard. The textile samples were finished with the ethanolic extract of Penicillium amestolkiae elv609, an endophytic fungus isolated from Orthosiphon stamineus Benth (common name: cat's whiskers). Endophyte is defined as microorganism that reside in the living plant tissue, without causing apparent disease symptom to the host. The antimicrobial efficacy of the ethanolic extract of P. minioluteum was tested on clinical pathogens isolated from diabetic wound. The extract exhibited significant inhibitory activity against 4 bacteria and 1 yeast with the minimal inhibitory concentration ranged from 6.25 to 12.5 mg/mL. The results indicate different susceptibility levels of the test microorganism to the ethanolic extract. However, the killing activity of the extract was concentration-dependent. The finished medical textile showed excellent antimicrobial efficacy on AATCC test assays. All the microbial cultures treated with the textile sample displayed a growth reduction of 99.9% on Hoheinstein Challenge Test. The wash durability of the finished textile was found good even after 50 washes with commercial detergent. Besides, the gas chromatography mass spectrometry analysis showed that 6-octadecenoic acid and diethyl phthalate were the main bioactive constituents of the extract. In conclusion, the developed medical textile showed good antimicrobial efficacy on laboratory tests. This work can be extended to in vivo trials for developing healthcare textile products for antimicrobial applications.

• Biomaterials and Biomechanics in Bioengineering
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• 제2권3호
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• pp.127-141
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• 2015

Silver-based systems activated by low intensity direct current continue to be investigated as an alternative antimicrobial for infection prophylaxis and treatment. However there has been limited research on the quantitative characterization of the antimicrobial efficacy of such systems. The objective of this study was to develop a semi-mechanistic pharmacokinetic/pharmacodynamic (PK/PD) model providing the quantitative relationship between the critical system parameters and the degree of antimicrobial efficacy. First, time-kill curves were experimentally established for a strain of Staphylococcus aureus in a nutrientrich fluid environment over 48 hours. Based on these curves, a modified PK/PD model was developed with two components: a growing silver-susceptible bacterial population and a depreciating bactericidal process. The test of goodness-of-fit showed that the model was robust and had good predictability ($R^2>0.7$). The model demonstrated that the current intensity was positively correlated to the initial killing rate and the bactericidal fatigue rate of the system while the anode surface area was negatively correlated to the fatigue rate. The model also allowed the determination of the effective range of these two parameters within which the system has significant antimicrobial efficacy. In conclusion, the modified PK/PD model successfully described bacterial growth and killing kinetics when the bacteria were exposed to the electrically activated silver-titanium implant system. This modeling approach as well as the model itself can also potentially contribute to the development of optimal design strategies for other similar antimicrobial systems.

• 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.

• 한국동물위생학회지
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• 제32권4호
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• pp.347-351
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• 2009

Bruella spp. involves a considerable danger of public health and farm animal industry. In this study, we assessed the disinfection efficacy of alkaline disinfectant solution and three commercial farm disinfectants (quaternary ammonium compound, sodium dichloroisocyanurate, potassium monopersulphate/sodium dichloroisocyanurate) against Brucella ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of selected disinfectants following exposure to test bacteria for 30 minutes at $4^{\circ}C$. Disinfectants and test bacteria are diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. Three commercial disinfectant showed excellent antimicrobial activity (up to dilution of $\times200$ in OM treatment). Alkaline disinfectant solution demonstrated favorable bactericidal efficacy against B. abortus (at dilution of $\times20$ in OM treatment). Three commercial farm disinfectants possess excellent efficacy against B. ovis. Alkaline disinfectant solution has lower potency than commercial farm disinfectant but could help to limit the spread of brucellosis.

• 대한화장품학회지
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• 제34권4호
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• pp.325-331
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• 2008

본 연구는 천연 식물 추출물을 이용하여 화장품 제형 내에서 천연 방부제로서 효능을 확인하기 위한 목적으로 진행하였다. 선별된 15종의 천연 식물 추출물을 이용하여 병원성 세균(Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli)과 효모균(Candida albicans), 곰팡이균(Aspergillus niger)에 대한 paper disc법(disc diffusion method)과 최소저해농도측정법(MIC)을 이용하여 항균 활성을 측정하였다. 그 결과 가자, 오배자 추출물은 그람 양성인 S. aureus와 그람 음성균인 P. aeruginosa, E. coli 에 대한 항세균 활성이 우수하였고, 계피 추출물은 효모균인 C. albicans와 곰팡이균인 A. niger에 대해 우수한 항진균 활성을 나타냈다. 최종 선별된 3종 외 식물추출물은 효과가 없었다. 항균 활성 효과가 우수한 최적 조합비로 구성된 가자, 오배자, 계피 추출물의 혼합 추출물을 화장품 제형에 첨가하여 제형 내 방부 활성을 측정한 결과 상업적으로 널리 사용되고 있는 파라벤 혼합 방부제와 유사한 정도의 방부 활성을 나타냄을 확인하였다. 결론적으로, 화학 방부제를 대신하여 천연 식물 추출물로만 이루어진 넓은 항균 스펙트럼을 갖춘 방부 시스템의 개발이 가능할 것으로 사료되며 최근 다양한 문제가 제기되고 있는 화학 방부제의 단점을 극복한 천연 방부제를 함유한 화장료의 개발에 응용 가능할 것으로 기대된다.

• 한국염색가공학회지
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• 제19권2호
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• pp.44-49
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• 2007

Antimicrobial fibers were prepared by an electro-spinning method. Polystyrene hydantoin(PSH) was employed as an antimicrobial precursor to produce an electro-spun antimicrobial acrylic fiber. Increasing the surface area of hydrophobic antimicrobial-fibers provides enhanced antimicrobial efficacy. The biocidal activity of electro-spun acrylic fibers could be rendered through chlorine bleach treatment, and the antimicrobial effectiveness against gram-Positive and gram-negative bacteria was investigated. In addition, scanning electron microscopy(SEM) demonstrated the feature of the electro-spun fibers.