• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2008년도 제49회 학술심포지움 및 국제학술대회
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• pp.65.1-65.1
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• 2008

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2008년도 제49회 학술심포지움 및 국제학술대회
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• pp.66.1-66.1
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• 2008

• 한국치위생학회지
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• 제18권1호
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• pp.9-18
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• 2018

Objectives: Pleurotus eryngii is used both for edible and medicinal purposes, and has a physiological activity. The purpose of this study is to investigate the antibacterial effect of Pleurotus eryngii against six oral pathogens (Staphylococcus aureus, Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, Streptococcus sobrinus, and Actinomyces viscosus). Methods: The antibacterial activities of various extracts of Pleurotus eryngii were examined by disc diffusion assay and minimum inhibitory concentration (MIC). The disc diffusion assay was performed by putting a paper disc soaked in extracts on plates inoculated bacterial cultures. The MIC of these extracts was determined by using a broth microdilution assay at a concentration ranging between 0.03 mg/ml to 15.00 mg/ml. The growth inhibition effect of extracts was measured at 600 nm for 24 hrs. Results: The antibacterial activity was confirmed against all six tested bacteria at Pleurotus eryngii ethyl acetate extract by the disc diffusion method. Acetone extract showed the antibacterial activity only against 4 strains containing Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, and Actinomyces viscosus. In ethanol extract, no activity was observed against other strains except Staphylococcus aureus. MIC values of ethyl acetate extract were the same, 7.50 mg/ml in all tested bacteria. Conclusions: Pleurotus eryngii exhibited the antibacterial activity against oral pathogens (Staphylococcus aureus, Streptococcus criceti, Streptococcus mutans, Streptococcus ratti, Streptococcus sobrinus, and Actinomyces viscosus). Thus, Pleurotus eryngii may be considered as a natural antibacterial agent for treatment of dental diseases.

• 한국응용과학기술학회지
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• 제41권2호
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• pp.283-291
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• 2024

본 연구는 스노우베리 추출물과 발효 추출물을 대상으로 피부 상재균인 Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans를 이용하여 천연화장품 소재로서의 항균 활성을 비교 평가하였다. 이를 위한 스노우베리 추출물의 항균 활성은 10-200mg/mL 농도에서 생육저해환(paper disc diffusion method)과 최소저해농도(Minimum inhibitory concentration)를 평가하였다. 스노우베리 추출물과 발효 추출물의 생육저해환을 확인하였을 때, 스노우베리 추출물의 경우 뿌리 추출물에서만 100mg/mL, 200mg/mL의 농도에서 항균력을 나타내었고, 발효 추출물의 경우 200mg/mL에서 항균력을 나타내는 것을 확인하였다. 그러나 스노우베리 추출물과 발효 추출물의 4종의 세균에 대한 항균력은 확인할 수 있었으나, 진균인 Candida albicans에서는 항균력을 확인할 수 없었다. MIC 결과 스노우베리 잎, 뿌리 추출물에서 발효의 경우 줄기 추출물에서 각 균에 대한 최소저해농도가 100mg/mL, 200mg/mL로 확인되었다. 이러한 결과는 스노우베리가 피부 개선을 위한 항균 소재 및 방부제로서의 활용 가치가 있다고 사료된다.

• 한국컴퓨터정보학회논문지
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• 제21권5호
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• pp.135-139
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• 2016

Scrophularia ningpoensis hemsl has been traditionally used in China and Vietnam for treatment of bacteria, atopy, pimple, tonsillitis, angina and encephalitis for a long time. The main objectives of this study were to evaluate the antibacterial activity of the Scrophularia ningpoensis hemsl extract on biofilm formation of Klebsiella pneumoniae. Antibacterial activity was conducted using disc diffusion assay and minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were determined using the broth micro dilution method in accordance to Clinical and Laboratory Standards Institute guidelines(CLSI). Furthermore, cytotoxicity on L929 were assessed using animal cell culture for the proliferation test(MTT cell assay) and the biofilm forming capacity of the K. pneumoniae were determined using the colony forming unit (CFU) assay. The extract exhibited considerable antibacterial activity. K. pneumoniae was susceptible to the extract with the MIC and MBC of 0.1875 and $1.5mg/m{\ell}$ respectively. Cytoxicity test in L929 showed no sign of toxicity at the concentration of $0.75mg/m{\ell}$ and at the same concentration the extract caused inhibition of bacterial biofilm formation. The extract of Scrophularia ningpoensis hemsl possesses an in vitro antibacterial antibiofilm activities against K. pneumoniae, with no sign of cytoxicity on L929.

• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1059-1064
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• 2014

Staphylococcus aureus is a major human pathogen, implicated in both community and hospital acquired infections. The therapy for methicillin-resistant Staphylococcus aureus (MRSA) infections is becoming more difficult because of multidrug resistance and strong biofilm-forming properties. Schiff bases have attracted attention as promising antibacterial agents. In this study, we investigated the in vitro activity of taurine-5-bromosalicylaldehyde Schiff base (TBSSB) against MRSA. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) were determined using a microtiter broth dilution method. TBSSB effectively inhibited planktonic MRSA, with an MIC of $32{\mu}g/ml$. The time-kill curve confirmed that TBSSB exhibited bactericidal activity against MRSA. TBSSB was also found to significantly inhibit MRSA biofilm formation at 24 h, especially at $1{\times}MIC$ and sub-MIC levels. Furthermore, scanning electron microscopy and transmission electron microscopy showed remarkable morphological and ultrastructural changes on the MRSA cell surface, due to exposure to TBSSB. This study indicated that TBSSB may be an effective bactericidal agent against MRSA.

• 급식외식위생학회지
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• 제1권1호
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• pp.27-35
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• 2020

Salt is a common seasoning agent used in various processed foods, especially in kimchi and salted seafood (jeotgal). This study was conducted to investigate the efficacy of salt with antimicrobial substances (acetic acid, garlic extract, carvacrol, nisin, thymol, and their combination (acetic acid+nisin+thymol)) on improvement of antibacterial effects of salt against foodborne pathogens. Salt (10%) was prepared using six different types of 0.2% natural antimicrobial substances. The antibacterial effect of salt combined with natural antimicrobial substances was evaluated against foodborne pathogens using the broth micro-dilution method and growth curve plotted using absorbance measurements. For the five foodborne pathogens, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of salt without antimicrobial substances as control were in the range of 24~>50,000 ㎍/mL and >50,000 ㎍/mL, respectively. Salt with nisin, thymol, or garlic extract showed strong inhibitory effects and their MIC against L. monocytogenes were 49, 12,500, and 24 ㎍/mL, respectively. In particular, salt with nisin showed inhibitory activities against Gram-positive bacteria. However, all the antimicrobial substances were less effective against Gram-negative bacteria such as E. coli O157:H7 and S. Typhimurium than Gram-positive bacteria. These results could be used for the development of salt with natural antimicrobial substances especially targeted against L. monocytogenes. This would enable the lowering of saline concentration while improving the storability of food.

• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1236-1239
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• 2006

Allyl alcohol (2-propen-l-ol), found in considerable amounts in heated garlic, was able to discriminate yeasts from bacteria and was approximately three orders of magnitude more inhibitory towards yeasts than bacteria. The average minimum inhibitory concentration (MIC) of allyl alcohol for bacteria and yeasts was 5.0% and 0.0056%, respectively. The unsaturated primary alcohols, including allyl alcohol and 2-buten-l-ol, seemed to work differently from all the other saturated alcohols and unsaturated secondary alcohols in inhibiting various yeasts. An alcohol dehydrogenase-negative (ADH$^-$) strain of Saccharomyces cerevisiae was as resistant to allyl alcohol as various bacteria, exhibiting an MIC of 5.0%. The unsaturated primary alcohols were apparently oxidized into the corresponding unsaturated aldehydes before they inhibited the yeasts.

• Journal of Microbiology and Biotechnology
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• 제10권2호
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• pp.227-232
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• 2000

Fresh pine needles were collected and extracted with 95% methanol and the extract was concentrated to determine its antimicrobial activity. The methanol extract had a considerable inhibitory effect on the tested bacteria, such as Esherichia coli 0157;H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. The methanol extract of pine needles was further fractionated to chloroform, ethylacetate, butanal, and water fractions. Among these four fractions, the butanol and water fractions, which showed a relatively strong inhibitory effect on all of the tested bacteria, were purified and the minimum ingibitory concentration (MIC) was determined for each microorganism. The MIC raged between 25 mg/ml and 45 mg/ml depending on the microorganism. the purified active fractions were applied to sterilized milk as a model food system to define the antimicrobial effectiveness and it was found that the antimicrobial activities in the water fractions were stronger than those in the butanol fractions.

• 한국약용작물학회지
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• 제18권5호
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• pp.315-322
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• 2010

This study was carried out to investigate the antimicrobial activities of organic extracts obtained from the fruit of Thuja orientalis L. The native fruits in Korea were collected and extracted by 80% ethanol, and the extract was sequentially fractionated with n-hexane, chloroform, ethylacetate, and butanol. The fraction yields of n-hexane, chloroform, ethylacetate, butanol and water of ethanol extract were 10.15%, 10.05%, 1.45%, 45.35% and 27.55%, respectively. n-Hexane-soluble fraction showed the highest antibacterial activity against gram positive bacteria, while the chloroform, ethylacetate, butanol and aqueous fractions did not show any antibacterial activity. Minimum inhibitory concentration (MICs) on Staphyloycoccus aureus, Bacillus subtilis and Sateptococcus pneumoniae, n-hexane-soluble fraction were $100\;{\mu}g$, $500\;{\mu}g$ and $50\;{\mu}g$/disc, respectively. The antibacterial activity was not destroyed by heating at 80, 100, $120^{\circ}C$ for 30 min and was not affected by pH. In the inhibitory test against the Staphylococcus aureus, Bacillus subtilis and Sateptococcus pneumoniae, n-hexane-soluble fraction showed potent growth inhibition at the concentration of 0.1 and $0.5\;{\mu}g/mL$ for 12~24 hours and n-hexane-soluble fraction did not show any mutagenic activity.