• Journal of Applied Biological Chemistry
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• 제49권4호
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• pp.131-134
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• 2006

The in vitro anti-fungal activity of hydroxylated fatty acids obtained from microbial conversion by Psuedomonas aeruginosa PR3 using ricinoleic acid(RA), eicosadienoic acid(EDA) and conjugated linoleic acid(CLA) as substrates, was investigated. Bioconverted hydroxylated fatty acids showed different anti-fungal activities potentials against the range of phytopathogenic fungi such as Botrytis cinerea, Rhizoctonia solani, Fusarium oxysporum, Sclerotonia sclerotiorum, Colletotricum capsici, Fusarium solani and Phytophthora capsici. RA and EDA showed up to 50% fungal mycelial inhibition at the concentration of $5{\mu}l\;ml^{-1}$. RA, EDA and CLA also exhibited anti-fungal activities with minimum inhibitory concentration(MIC), ranging from 500 to $1000{\mu}g\;ml^{-1}$. Screening was also carried out using varied concentrations of bioconverted RA and EDA for determining the anti-fungal effect on the spore germination of different fungi. Bioconverted RA and EDA showed a considerable degree of spore germination inhibition.

• 복식문화연구
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• 제11권3호
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• pp.441-446
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• 2003

Water-insoluble chitosan with molecular weight of 2,000,000, 500,000, 80,000, and 40,000 and more than 90% of degree of deacetylation were used to test antibacterial activity of chitosan against a pathogenic bacteria, methicillin resistant Staphylococcus aureus(MRSA), which is being issued in the world. As experimental method, Agar plate Smear Method and Agar plate Contact Method were used. The moleculur weight of chitosan didn't exert significant influences on its antibacterial activity against MRSA but chitosan having molecular weight 40,000, 80,000 and 150,000 showed the excellent antibacterial activity. The antibacterial efHciency was excellent in applying it after chitosan was dissolved in acetic acid solution, while the antibacterial efficiency was not expressed nearly in case of applying after chitosan was dissolved in neutral water. Therefore, it is considered that chitosan can show the antibacterial efficiency only if a positive ion status of -NH₃/sup +/ is maintained. MIC of chitosan/acetic acid solution and cotton fabrics finished with chitosan/acetic acid solution showed in concentration of 0.05%.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.220-223
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• 2000

Sophorolipid, a glycolipid type biosurfactant produced from Candida Bombicola, inhibited the growth of bacteria and fungi. Between two types of sophorolipid, acid and lactone form, the latter had more strong antimicrobial activity. Culturing parameters including oil substrate, initial glucose concentration, aeration, culture mode, affected the ratio of two forms. The fatty acid moety varied depending on the oil having different fatty acid chains. Minimum inhibitory concentration of lactonic sophorolipid toward Propionibacterium acne was below 0.5ppm. This result indicated the potentials of sophorolipid as antimicrobial agent in various area including cosmetics.

• Journal of Nutrition and Health
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• 제36권2호
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• pp.147-153
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• 2003

In this study, Artemisia capillaries, which has been used as a folk remedy, was investigated for its antimicrobial activity. First, the Aremisia capillaris was extracted with methanol at room temperature, and fractionation of the methanol extracts from Artemisia capillaris was carried out using petroleum ether, chloroform, and ethyl acetate. Second, the antimicrobial activity of the Artemisia capillaris extracts was determined using a paper disc method and minimum inhibitory concentration of ethyl acetate extracts from Artemisia capillaris against food-borne pathogens and food spoilage bacteria was measured. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Artemisia capillaris against Staphylococcus aureus and Salmonella typhimurium. The ethyl acetate extract of Artemisia capillaris showed strong antimicrobial activity against S. typhimurium at a concentration of 1,000 ppm. The 3,000 ppm of ethyl acetate extract from Artemisia capillaris retarded the growth of S. aureus and S. typhimurium for up to 6 hours.

• 대한수의학회지
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• 제24권2호
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• pp.163-168
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• 1984

The in vitro activity of penicillins(penicillin G, ampicillin, carbenicillin, methicillin and cloxacillin) and gentamicin to Staphylococcus aureus and coagulase-negative staphylococci isolated from bovine mastitic milk samples was determined. The growth of all isolates of staphylococci tested was inhibited by cloxacillin and methicillin at a concentration of $0.78{\mu}g/ml$ and by gentamicin at a minimum inhibitory concentration (MIC) of $1.56{\mu}g/ml$. Of the 140 strains of Staphylococcus aureus isolated 99(70.7%) gave positive reactions for penicillinase on the starch-iodine test. Of 121 isolates of coagulase-negative staphylococci, 58(47.9%) showed penicillinase production, but all the Staph. xylosus lacked the ability to produce penicillinase. MIC of penicillin G of the penicillinase-positive strains was $0.2{\mu}g/ml$ or more. The combination of cloxacillin with gentamicin showed a synergistic effect by inhibiting regrowth of the tested organism.

• 한국식품영양학회지
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• 제19권4호
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• pp.526-531
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• 2006

자몽 종자 추출물의 항균성을 조사하기 위하여 그람 양성균인 Bacillus cereus, Bacillus subtilis, Listeria monocytogenes와 그람 음성균인 Escherichia coli, Salmonella enteritidis, Serratia marcescem를 대상으로 하여 최소 저해 농도, 생육 저해 활성, 콜로니 형성 저해 활성을 실험하였다. 그람 양성균에 대한 자몽 종자 추출물의 최소 저해 농도는 12.5 ppm정도로 상대적으로 낮았으며, 그람음성균의 최소저해 농도는 50ppm 이상으로 상대적으로 높았다. 균주의 증식에 대한 생육 저해 활성을 조사한 결과 Bacillus cereus는 1ppm 이하, Bacillus subtilis는 6.25 ppm, Listeria monocytogenes는 1ppm 이하, Escherichia coli는 6.25 ppm, Salmonella enteritidis는 25 ppm Serratia marcescem는 25pp부터 생육이 저해되었다. 그람 양성균의 콜로니 형성 저해활성은 Bacillus cereus는 93.9%, Bacillus subtilis는 94.0%, Listeria monocytogenes는 99.9%, 그람 음성균의 콜로니 형성 저해 활성은 Escherichia coli는 4.4%, Salmonella enteritidis는 82.7%, Serratia marcesem는 86.4%로, 그람 양성균에 대해서는 높은 저해 활성을 보였으며, 그람 음성균에 대해서는 비교적 낮은 저해 활성을 보였다.

• 대한한방내과학회지
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• 제34권3호
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• pp.278-288
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• 2013

Objectives : Methicillin-resistant Staphylococcus aureus (MRSA) has a cephalosporin and beta-lactam antibiotic-resistant strains. MRSA is one of the major pathogens causing hospital infection and the isolation ratio of MRSA has gradually increased. Consequently, increased resistance to antibiotics is causing serious problems in the world. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infectious diseases. Methods : The antibacterial activities of Ipyo-san were evaluated against 2 strains of MRSA and 1 standard Methicillin-susceptible staphylococcus aureus (MSSA) strain by using the disc diffusion method, minimal inhibitory concentrations (MIC) assay, colorimetric assay using MTT test, checkerboard dilution test and time-kill assay performed under dark. Results : The MIC of Ipyo-san water extract against S. aureus strains ranged from 1000 to $2,000{\mu}g/ml$, so we confirmed that it had a strong antibacterial effect. Also, the combinations of Ipyo-san water extract and conventional antibiotics exhibited improved inhibition of MRSA with synergy effect. We suggest that Ipyo-san water extract against MRSA has antibacterial activity so it has potential as alternatives to antibiotic agents. For the combination test, we used Triton X-100 (TX) and DCCD for measurement of membrane permeability and inhibitor of ATPase. As a result, antimicrobial activity of Ipyo-san water extract was affected by the cell membrane. Conclusions : We suggest that the Ipyo-san water extract lead the treatment of bacterial infection to solve the resistance and remaining side-effect problems that are the major weak points of traditional antibiotics.

• 한국식품위생안전성학회지
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• 제15권1호
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• pp.55-59
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• 2000

Bamboo oil의 천연 보존료로서의 가치를 평가하기 위해 합성 보존료인 BHA와 이미 수입되어 사용되고 있는 천연보존료인 tea tree oil을 비교하기 위하여 disc diffusion법과 broth dilution 법으로 S. aureus와 E. coli대한 항균력을 검토한 결과를 요약하면 다음과 같다. 1. Disc diffusion법으로 S. aureus에 대한 항균력을 조사한 결과 BHA>tea tree oil>bamboo oil 순이었고 E. coli에 대한 항균력은 bamboo oil이 가장 강하게 나타났으며 다음은 BHA>tea tree oil순으로 나타났다. 2. Broth dilution법으로 S. aureus와 E. coli모든 시료 6.0$\mu$l/ ml 이상에서 모두 측정되지 않아 모든 시료에서 동일하게 최소억제농도가 6.0$\mu$l/ ml 이상 필요한 것으로 나타났다. 3. Bamboo oil의 이용 개발 시 경제적 조건은 동일한 항균력을 기대할 때 tea tree oil에 비하여 약 20%정도 저렴하여 경제성이 충분히 있는 것으로 나타났다.

• 한국임상수의학회지
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• 제34권4호
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• pp.261-267
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• 2017

The aim of this study was to investigate the antibacterial properties of chitosan silver nanocomposites (CAgNCs) using pathogenic Vibrio ichthyoenteri as a bacterial model. Results of agar disc diffusion and turbidimetric assays showed that CAgNCs could inhibit the growth of V. ichthyoenteri in concentration dependent manner. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CAgNCs were 75 and $125{\mu}g/mL$, respectively. Furthermore, CAgNCs treatment induced the reactive oxygen species (ROS) level in V. ichthyoenteri cells in concentration and time dependent manner, suggesting that it generates oxidative stress, leading to bacterial cell death. The field emission scanning electron microscope (FE-SEM) images of CAgNCs treated V. ichthyoenteri exhibited strong cell membrane damage than un-treated control bacteria. MTT assay results showed the highest cell viability (22%) at $75{\mu}g/mL$ of CAgNCs treated bacteria samples. The results from this study suggest that CAgNCs is a potential antibacterial agent to control fish pathogenic bacteria.

• 동의생리병리학회지
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• 제19권5호
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• pp.1233-1237
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• 2005

Catechin products in green tea extract was prepared to investigate antibacterial activity on the pathogenic bacteria. Survival of pathogenic bacteria (MASA - methicillin resistant Staphylocouus aureus, E.coli O157 and S. typhimurium Sal-13) in tryptic soy agar(TSA) containing Catechin products powder incubated at various concentration was evaluated. TSA containing $0{\sim}2%(w/v)$ of Catechin products was inoculated approximately $10^4\;CFU/ml$ of pathogenic bacteria and incubated at $37^{\circ}C$ for 24 hours. The plate counting technique and clear zoon test were used to test survival effect of the Catechin products. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was derived from the survival curves of pathogenic bacteria. S. typhimurium Sal-13 was the most sensitive strain to Catechin products. This result suggested that Catechin products can be used as an effective natural antibacterial agent.