• Fisheries and Aquatic Sciences
• /
• 제16권2호
• /
• pp.79-84
• /
• 2013

In an effort to discover an alternative antibiotic for treating infections with methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas sp. UJ-6, a marine bacterium that exhibited antibacterial activity against MRSA, was isolated. The culture broth and its ethyl acetate extract exhibited bactericidal activity against MRSA. The extract also exhibited antibacterial activity against gram-negative bacteria, which were not susceptible to vancomycin. The treatment of MRSA with the extract resulted in abnormal cell lysis. The extract retained >95% of its anti-MRSA activity after heat treatment for 15 min at $121^{\circ}C$. Thus, although most antibiotics are unstable under conditions of thermal stress, Pseudomonas sp. UJ-6 produces a heat-stable anti-MRSA substance. The results of this study strongly suggest that Pseudomonas sp. UJ-6 can be used to develop a novel, heat-stable, broad-spectrum antibiotic for the treatment of MRSA infections.

• 한국식품저장유통학회지
• /
• 제14권2호
• /
• pp.194-200
• /
• 2007

전통발효식품의 기능성 및 저장성을 증진시킬 목적으로 전통된장으로부터 효소활성 및 항균활성이 우수한 CH-14 균주를 분리하여 그 특성을 검토하였다. 분리한 CH-14 균주는 그람양성, catalase 양성, oxidase 음성, 내생포자 및 편모를 가지는 간균으로 세포의 크기는 $0.5-0.7{\times}3.5-4.2{\mu}m$이었다. 최종 분리균을 Bergey's Manual of Systematic Bacteriology 및 Bergey's Manual of Determinative Bacteriology와 API 50 CHL Kit에 의한 당 발효실험의 결과를 토대로, Bacillus subtilis로 밝혀져 Bacillus subtilis CH-14로 명명하였다. 최적배지의 조성을 검토한 결과, 탄수원은 2% cellobiose, 질소원은 yeast extract와 peptone을 각각 0.5%씩 혼합 첨가하는 것이 효과적이었다. 무기염은 0.05%의 $MgSO_4{\cdot}7H_2O$가 적당하였다. 최적 생육온도 범위는 $30^{\circ}C-45^{\circ}C$이었으며, 초기 pH 범위는 pH 4.5-10.0이었다. 배양시간에 따른 항균물질의 생산성을 검토한 결과, 배양 24시간이 최대의 활성을 나타내었다. 다양한 종류의 유해미생물에 대한 최소저해농도(MIC)를 검토한 결과, E. coli와 P. mirabilis에 대해서는 5 mg/mL, S. aureus, S. enteritidis, V. parahaemolyticus에 대해서는 10mg/mL를 나타내었다.

• 한국미생물·생명공학회지
• /
• 제44권3호
• /
• pp.246-253
• /
• 2016

The antibacterial activities of thirty mushroom species belonging to Basidiomycetes and Ascomycetes, cultivated on two liquid media, were evaluated against gram-positive (Bacillus subtilis and Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria by the disk diffusion method. All of the mushrooms, except Auriporia aurea, Fomes fomentarius, and Lyophyllum shimeji, showed different antibacterial activity levels—from 9.5 mm in diameter of the inhibition zone to full inhibition of growth of the test bacteria. The antibacterial activities of Crinipellis schevczenkovi, Hohenbuehelia myxotricha, Oxyporus obducens, and Spongipellis litschaueri were observed for the first time. The antibacterial potential of culture liquids of the investigated species was higher than that of their mycelia activity. Dependence of the intensity of antibacterial activity on the culture medium was shown. The antibacterial efficiency of the most active species (Lentinus edodes, Piptoporus betulinus, and Phellinus igniarius) was verified and compared with those of some commercial antibiotics and natural essential oils of Salvia and Eucalyptus. The culture liquid of Piptoporus betulinus, obtained after cultivation on glucose-peptone-yeast culture medium, is a potential substance for further creation of antibacterial products.

• Fisheries and Aquatic Sciences
• /
• 제11권1호
• /
• pp.1-6
• /
• 2008

In an effort to discover an alternative therapeutic agent against methicillin-resistant Staphylococcus aureus (MRSA), several medicinal plants and seaweeds were evaluated for its antibacterial activity against MRSA. A methanolic extract of the Phaeophyta Ecklonia stolonifera exhibited significant antibacterial activity against MRSA. To perform more detailed investigation on antibacterial activity, the methanol extract of E. stolonifera was further fractionated with organic solvents such as hexane, dimethylchloride, ethyl acetate, and n-butanol. Among them, the hexane fraction showed the strongest antibacterial activity against MRSA strains with MIC from 500 to $600 {\mu}g/mL$. The fraction also exhibited a bactericidal activity against MRSA, indicating that E. stolonifera contains a bactericidal substance against MRSA.

• 한국미생물·생명공학회지
• /
• 제33권2호
• /
• pp.142-147
• /
• 2005

The objective of this study was to develop a new potent antibacterial compound against bovine pneumoniae bacteria from medicinal plants or herbs. Among 65 kinds of medicinal plants and herbs, ethanol extracts of Citrus unishiu showed the highest solid yield of $54\%$. However, ethanal extracts from Agastache rugosa had the highest antibacterial activities against bovine pneumoniae bacteria, Mannheimia haemolytica A and Haemophilus somnus (size of clear zone: 16.0 mm and 10.0 mm, respectively). The antibacterial compound was also maximally extracted when the powder of A. rugosa was treated with $70\%$ ethanol at $45^{\circ}C$ for 12 hours.

• 대한의생명과학회지
• /
• 제28권1호
• /
• pp.50-57
• /
• 2022

In this study, we tried to examine the possibility of developing a dental product such as tooth decay prevention and oral hygiene by manufacturing a natural polymer film for oral use. Natural polymer films were prepared from shark byproduct extract (SBE) and gellan gum (GG). As an antibacterial substance, the antibacterial activity of green tea extract against tooth decay-causing bacteria was measured. An film was prepared by adding green tea extract to the composition of SBE and GG. The mechanical, solubility, moisture content and antibacterial function of the prepared film were investigated in detail. Also, the incorporation of GTE into the SBE/GG film improved the physical performance of the film. Increasing the content of GTE improved the antioxidant and antibacterial properties of the film. Formulation of antimicrobial SBE/GG film containing green tea extract was established and these results evidently showed potential for cavity prevention products application.

• 한국의류산업학회지
• /
• 제5권4호
• /
• pp.395-398
• /
• 2003

In this study, we measured the antibacterial activities, deodorization, UV cut ability, whiteness and SEM, according to the size($5{\mu}m$, $15{\mu}m$) of $TiO_2$, concentration(3%, 5%, 10%) and dipping temperature($50^{\circ}C$, $70^{\circ}C$) with using anatase type of $TiO_2$ photocatalyst. Photocatalyst is the substance which carries out functions, such as decomposition, removal, deodorization, antibacterial, etc. of a contaminant, in a place with light based on an oxidation-reduction reaction. The results of this study were as follow. Antibacterial activities are increased with increasing of the $TiO_2$'s concentration, and $TiO_2$ has high antibacterial activities for Staphylococcus aureus but it has low antibacterial activities for Klebsiella pneumoniae. The deodorization and UV cut ability is very good, therefore be able to get good effects with using only 3% of $TiO_2$. Every effects are increased by using small size of $TiO_2$ and high dipping temperature.

• 대한방사선기술학회지:방사선기술과학
• /
• 제44권3호
• /
• pp.219-224
• /
• 2021

The purpose of these experiments is often to scan infected patients with MRI. Therefore, it is to investigate whether the antibacterial film containing silver ions, which is a non-magnetic substance, affects magnetic resonance imaging. In this experiment, the ACR phantom was used, not the patient. The ACR phantom was wrapped in an antibacterial film and the SNR, CNR, sagittal localization image, and geometrical accuracy were compared before and after. The experiment was performed 10 times and the averaged values were compared. There were no significant differences in the results of all experiments. The FDA recommends removing metal and antibacterial film masks during MRI scans. The reason is that there was one case of injury with facial burns. When I touched the antibacterial film to check the fever during the 2 hour experiment, I did not feel any particular fever. In light of the experimental results, it would be helpful to use an antibacterial film when testing an infected patient. The reason is that there isn't a difference before and after the experiment of SNR, CNR, and sagittal localization images.

• 한국환경과학회지
• /
• 제11권1호
• /
• pp.33-40
• /
• 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.

• 대한한방내과학회지
• /
• 제24권2호
• /
• pp.269-282
• /
• 2003

Water and ethanol extracts of 67 species of medicinal plants were tested to determine antimicrobial activity against Helicobacter pylori. Among them, the extracts of Coptis japonica showed the best antibacterial activity. The extract of C. japonica showed four major spots on TLC plate and the Rf values of the spots were 0.07, 0.13, 0.21 and 0.73, respectively. Except for the spot of Rf 0.73, other three spots inhibited the cell growth of H. pylori. As shown in HPLC analysis, three antimicrobial spots contain berberine, major antimicrobial substance of C. japonica. However, the spot of Rf 0.13 had higher activity than berberine. The concentrated water extract of three prescribed medicines related with C. japonica showed good antibacterial activity against H. pylori.