• KSBB Journal
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• v.30 no.2
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• pp.69-76
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• 2015

The antibacterial activity of a antimicrobial (organic synthetic or organic natural material) on the bacteria (Bacillus megaterium, Arthrobacter oxydans, Micrococcus luteus, Methylobacterium aquaticum) detected in the automobiles showed 99.9% bacteria decrease rate within 30 min of being in contact with the tested bacteria culture. The MIC of the organic synthetic material based antimicrobials and the organic natural material based antimicrobial on the bacteria were 31~500 mg/mL and 8~250 mg/mL, respectively. The bacteria and biofilms were formed on the surface of aluminum after 5 ~8 days in the case of addition of the organic synthetic material based antimicrobial to the MIC values for the tested bacteria culture. On the other hand, there was no proliferation of bacteria and formation of biofilms on the surface of aluminum even after 30 days in the case of addition of the organic natural material based antimicrobial to the MIC values for the tested bacteria culture. As a result, the organic natural material based antimicrobial was confirmed to be more excellent effect of inhibition of bacterial proliferation and restraint of biofilms formation than the organic synthetic material based antimicrobial.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.2
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• pp.137-145
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• 2016

This study screened the biological activity of an acidified gill extract of the Manila clam Ruditapes philippinarum including antimicrobial, hemolytic, membrane permeabilization, and DNA-binding activity, and purified the antimicrobial material. The acidified gill extract showed potent antimicrobial activity against Bacillus subtilis and Escherichia coli without significant hemolytic activity, but showed no membrane permeabilization or DNA-binding ability. An antimicrobial material was purified from the acidified gill extract using C₁₈ reversed-phase and cation-exchange high-performance liquid chromatography (HPLC). Treatment of the purified material with trypsin completely abolished all of the antibacterial activity against Bacillus subtilis, suggesting that the purified material is a proteinaceous antibiotic. The molecular weight of the purified material was 2571.9 Da, but no primary structural information was obtained due to N-terminal blocking. A future study should confirm the primary structure. Our results suggest that the Manila clam gill contains proteinaceous antibiotics that have a role in first-line defense. This information could be used to better understand the Manila clam innate immune system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.52-53
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• 2013

According to the increases the standard of living of the people, requirements for building environments are also being diversified. The fungus that occurred the building is not good the health of occupants as well as undermine the value of the building. However, chemical antimicrobial agent contain ingredients harmful to human body and it has an impact on indoor air quality. Therefore, the use of natural antimicrobial material is strongly required. In this study, the fungal reproductive inhibit capacity was evaluated by using mortars with natural antimicrobial material.

• International Journal of Concrete Structures and Materials
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• v.18 no.3E
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• pp.165-171
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• 2006

Environment-friendly materials are increasingly used as building construction materials nowadays, and the market share of those is growing. Accordingly, the research and developments in terms of environmental value are progressing steadily now. The main characteristics of environmental products are far-infrared radiation, negative-ion emission, electromagnetic wave shielding, and antimicrobial property. These products are often used in mortar and as spray on the finishing material. Nevertheless, there are hardly any research on the functional properties of concrete, the main material in construction field. Thus, we evaluated such basic properties of concrete as slump, compressive strength and air content while using such functional materials as sericite, wood-pattern sandstone, carbon black and nano-metric silver solution to focus on their functional properties like far-infrared radiation, negative ion emission, electro magnetic wave shielding, and antimicrobial activity in this research. The results indicated that the most useful material in the functional materials was carbon black. Sericite and nano-metric silver solution had a little effect on the functional property. Moreover, although wood-pattern sandstone had very high functional property, it exhibited too low compressive strength to be applied, to concrete as a factory product. Antimicrobial property of nano-metric silver solution in the concrete was not clear demonstrated, but if these specimens were to be aged in $CO_2$ gas for a long time, it might be apparent.

• Korean Journal of Materials Research
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• v.29 no.12
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• pp.735-740
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• 2019

The purpose of this study is to fabricate an ophthalmic lens by copolymerizing two types of carbon nanotubes and hydrophilic hydrogel lens materials, and to investigate its application as an ophthalmic lens material by analyzing its physical properties and antimicrobial effect. For polymerization, HEMA (2-hydroxyethyl methacrylate), EGDMA (ethylene glycol dimethacrylate), a crosslinking agent, and AIBN (azobisisobutyronitrile), an initiator, are used as a basic combination, and a single-walled carbon nanotube and a single-walled, carboxylic-acid-functionalized carbon nanotube are used as additives. To analyze the physical properties, the water content, refractive index, breaking strength, and antimicrobial effect of the fabricated lenses are measured. The fabricated lenses satisfies all the basic properties of the basic hydrogel ophthalmic lens. The water content increases with increasing amount of additive and decreases with addition of 0.2 % ratio of nanoparticles. The refractive index is inversely proportional to the water content result. As a result of the antimicrobial test of the fabricated lens, the addition of carbon nanotubes shows an excellent antimicrobial effect. Therefore, it is considered that the fabricated lens can be applied as a functional material for basic ophthalmic hydrogel lenses.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.371-377
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• 1999

In order to evaluate the antimicrobial function of natural herb extracts as antimicrobial agent or packaging material for the preservation of foods and greenhouse produce, the water extract of chopi (Zanthoxylum piperitum DC.) was prepared and its antimicobial activity was determined. In the paper disk test its antimicrobial activity was increased in proportion to its concentraion. The growth of microorganisms was completely inhibited above 500ppm of its concentration. It showed wide spectrum of thermal(40 to 180oC) and pH(4 to 10) stabilities. In the electronic microscopic observation(TEM and SEM) of microbial morphological change it showed to decrease the activation of physiological enzymes and to lose the function of cell membranes. Even in the activation test of galactosidase, it seemed to weaken the osmotic function of cell membranes remarkably in comparison with chloroform and its activation corresponded to 40~50% of toluene. Zanthoxylum piperitum DC. extract seemed to be an excellent antimicrobial for the inhibition of food borne microorganisms as well as the pre servation of greenhouse produces.

• Fashion & Textile Research Journal
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• v.15 no.4
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• pp.630-634
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• 2013

Cow leather coated with polyurethane film that contains various organic photosensitizers was investigated to demonstrate the antimicrobial properties in the application of the material to protective clothing and home appliances. To prepare the antimicrobial coating on leather surfaces with high potency against microbes, photoactive agents, such as benzophenone (BP), 4,4'-bis(dimethylamino) benzophenone (MK), 4,4'-dihydroxybenzophenone (DHBP) and methylene blue (MB), were incorporated into polyurethane-based coating solutions. The photoactive antimicrobial agent treated leather samples were characterized by SEM, color appearance, color fastness against abrasion, and antimicrobial tests. The optical properties of organic photosensitizers indicated that active UV absorbance ranges were different: BP (around 250 nm), MK (around 360 nm), DHBP (around 305 nm) and MB (around 295 nm &570 nm-685 nm). The intensity of the UV absorbance curve at the UVA light wavelength for the antimicrobial test showed the highest value with MK; subsequently, this was followed by MB, DHBP and BP in decreasing order. The treated-leather samples demonstrated excellent antibacterial activity under UVA light. The antimicrobial effects for the Staphylococcus aureus were superior to Escherichia coli. Moreover, the polyurethane finishing showed an effective durability to abrasion. The overall results indicated that DHBP is the most suitable PU coating additive to provide antimicrobial properties to leather as well as color and surface appearance than MK, MB, and BP.

• Journal of the Korean Magnetic Resonance Society
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• v.6 no.1
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• pp.69-77
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• 2002

During the screening of material which has the antimicrobial activity against aminoglycoside-resistant bacteria, A new material $\varepsilon$-(L-$\beta$-Iysine) polypeptide from a culture medium of Streptomyces sp.(DWGS2) was isolated, and the structure and the physicochemical properties of the new material were elucidated. The new material was separated by column chromatography of the culture medium using Dowex1$\times$2, Silica gel, and Sephadex LH20 etc. The chemical structure and molecular weight were determined with the data of various NMR experiments, MALDI mass, and ESI mass experiments. The antimicrobial activity of $\varepsilon$-(L-$\beta$-Iysine) polypeptide is not only better than equal to the activity of known aminoglycoside type of antibiotics(MIC=3.125 - 6.25ug/mL) but also effective against aminoglycoside-resistant bacteria and fungi. If the mechanism of antimicrobial activity against aminoglycoside- resistant bacteria is figured out, the $\varepsilon$-(L-$\beta$-Iysine) polypeptide can be utilized for the treatment of diseases caused by aminoglycoside-resistant bacteria.

• Environmental Engineering Research
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• v.13 no.3
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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.

• Journal of Food Hygiene and Safety
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• v.10 no.1
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• pp.23-28
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• 1995

The effect of the ethanol extract from salviae miltiorrhizae radix (Salvia miltiorrhiza) on the microbial growht and the stability of the extracted antimicrobial material were investigated. The ethanol extract had strong growth inhibition activity (MIC, 3.13~50.0 $\mu\textrm{g}$/ml) against Gram-positive bacteria such as B. subtilis, L. monocytogenes and S. aureus. Among Gram-positive bacteria tested, B. subtilis was the most susceptible to the extracted substance. While the antimicrobial activity of the ethanol extract was weak (MIC, 400~800 $\mu\textrm{g}$/ml) to E. coli and yeasts (C. albicans, Sacch. diastaticus). The ethanol extract had bactericidal action at higher concentration than MIC against B. subtilis, while the extract had only bacteriostatic action against S. aureus. The extracted antimicrobial substance was stable in the pH range of 4.0 to 10.0, heat treatment at 121$^{\circ}C$ for 15 min, and freezing and thawing