• 한국미생물·생명공학회지
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• 제27권5호
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• pp.354-358
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• 1999

In order to know the antifungal characteristics of saturated fatty acids having 6 to 12 carbons, their minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) were estimated against Saccharomyces cerevisiae. Fatty acids from C6 to C11 exhibited increasing activity with chain length, but C12 fatty acid did not show activity at all. In relation to antifungal modes of actions, fatty acids investigated showed on inhibitory activity toward the plasma membrane H+-ATPase of Saccharomyces cerevisiae. Their inhibitions to the glucose-induced acidification and ATP hydrolysis caused by the proton pump were found to be in common wiht antifungal activities. At the test concentration of 1mM, hexanoic acid (C6) showed the lowest inhibition of about 30%, while undecanoic acid(C11) showed the strongest inhibition of over 90%. In addition, as seen with antifungal activity, the inhibitory activity of dodecanoic acid (C12) was suddenly reduced to less than 50%.

• 한국식품위생안전성학회지
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• 제33권6호
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• pp.427-437
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• 2018

In this study, 23 ethanolic extracts from 20 medicinal plants were evaluated for biological activities. Results revealed that of 23 samples, seven samples have demonstrated good antimicrobial activity. Minimum inhibitory concentrations were 0.4-2.0 mg/mL, while minimum bactericidal concentrations were mostly high 0.8-2.0 mg/mL for selected seven samples. Five samples revealed > 70 mg gallic acid equivalent (GAE)/g of total phenolic contents. Among test samples, six samples exhibited > 80% inhibition of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and only two samples exhibited > 80% inhibition of 2,2'-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radicals. A total of five test samples revealed Trolox equivalent antioxidant capacity more than $1000{\mu}m/g$. The MTT assay indicated that eight test samples exhibited > 90% viability of murine macrophage cells (RAW 264.7) at $250{\mu}g/mL$ and suppressed iNOS mRNA expression at transcriptional level when stimulated by lipopolysaccharide (LPS). Some medicinal plants revealed promising results, and so they have prospective for further more inclusive studies.

• 대한약침학회지
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• 제25권1호
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• pp.37-45
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• 2022

Objectives: The quorum-sensing-inhibitory and anti-biofilm activities of the methanol extract of E. globulus leaves were determined against clinically isolated multidrug-resistant Pseudomonas aeruginosa. Methods: The preliminary anti-quorum-sensing (AQS) activity of eucalyptus was investigated against a biosensor strain Chromobacterium violaceum ATCC 12472 (CV12472) by using the agar well diffusion method. The effect of sub-minimum inhibitory concentrations (sub-MICs) of the methanol extract of eucalyptus on different quorum-sensing-regulated virulence factors, such as swarming motility, pyocyanin pigment, exopolysaccharide (EPS), and biofilm formation, against clinical isolates (CIs 2, 3, and 4) and reference PA01 of Pseudomonas aeruginosa were determined using the swarm diameter (mm)-measurement method, chloroform extraction method, phenol (5%)-sulphuric acid (concentrated) method, and the microtiter plate assay respectively, and the inhibition (%) in formation were calculated. Results: The preliminary AQS activity (violacein pigment inhibition) of eucalyptus was confirmed against Chromobacterium violaceum ATCC 12472 (CV12472). The eucalyptus extract also showed concentration-dependent inhibition (%) of swarming motility, pyocyanin pigment, EPS, and biofilm formation in different CIs and PA01 of P. aeruginosa. Conclusion: Our results revealed the effectiveness of the E. globulus extract for the regulation of quorum-sensing-dependent virulence factors and biofilm formation at a reduced dose (sub-MICs) and suggest that E. globulus may be a therapeutic agent for curing and controlling bacterial infection and thereby reducing the possibility of resistance development in pathogenic strains.

• Applied Biological Chemistry
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• 제38권4호
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• pp.289-292
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• 1995

무화과잎으로부터 천연 항미생물 물질의 개발을 검토할 목적으로 무화과잎을 메탄올로 추출하고 ethyl acetate와 buffer용액을 이용하여 용매분획하였고 각 분획에 대한 항미생물 활성을 측정하였으며 활성이 강한 분획에 대한 최소저해농도(MIC)와 최소치사농도(MLC)를 측정하였다. 무화과 잎중의 항미생물 활성은 산성 분획과 페놀성 분획에서 강하게 나타났으며 미생물의 종류에 관계없이 활성범위가 넓었다. 페놀성 분획이 산성 분획에 비하여 MIC와 MLC값이 상대적으로 낮았고 MIC값의 경우 두 분획이 공통적으로 세균보다는 진균류에 대하여 낮았으며 특히 저온세균인 Pseudomonas aeruginosa에 대한 MIC와 MLC값이 대단히 낮음을 알 수 있었다.

• 생약학회지
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• 제40권1호
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• pp.70-76
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• 2009

Thirty six essential oils from herb drugs entered in Korean official formulary, which are frequently used in oriental region, were tested for antibiotic resistance inhibition. When the oils were combined with ampicillin (Am) or amoxicillin (Amx) they showed significant inhibitory effects on the growth of multi-drug resistant Staphylococcus aureus SA2 in considerably low concentration. The most effective combinations were oils from Acanthopanacis Cortex ($0.49{\mu}g/mL$) with Am and Cnidii Rhizoma and Lonicerae Flos (2.77 and $2.79{\mu}g/mL$, respectively) with Amx as shown in minimum resistance inhibitory concentrations.

• 한국식물병리학회지
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• 제11권3호
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• pp.245-251
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• 1995

Nine hundred and ninety-two isolates of Botrytis cinerea were obtained from infected strawberries, tomatoes and cucumbers in Taejon, Gongju, Puyo, Nonsan and Kimhae in Korea. Six hundred forty-two (64.7%) isolates were benomyl resistant (BR), 245 (24.7%) were procymidone resistant (PR), and 105 (10.6%) were dichlofluanid resistant (DR). In the minimum inhibitory concentration (MIC) test, DR isolates showed mycelial growth on the PDA incorporated with 100 or 500 $\mu\textrm{g}$/ml of dichlofluanid, while dichlofluanid sensitive (DS) isolates did not grow on the PDA incorporated even with 10 $\mu\textrm{g}$/ml of dichlofluanid. Chemical concentrations for inhibition of spore germination were much lower than those for inhibition of mycelial growth. IC50 values, the effective concentrations for 50% inhibition of spore germination, for DR were 0.11~0.29 $\mu\textrm{g}$/ml, whereas they were 0.04~0.09 $\mu\textrm{g}$/ml for DS isolates. In comparison of fitness-related characteristics such as virulence, sclerotial formation, and sporulation, DR isolates were inferior to DS isolates. However, mycelial growth was little different between DR isolates and DS isolates.

• 대한통합의학회지
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• 제11권4호
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• pp.125-133
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• 2023

Purpose : This study aimed to analyze the antibacterial activity of Liriope platyphylla ethanol extract (LPEE) against Streptococcus mutans and Porphyromonas gingivalis and to validate its potential for the prevention and treatment of dental caries, gingivitis, and periodontal disease. Methods : To verify the antibacterial effect of L. pulsatilla ethanolic extract (LPEE) against S. mutans and P. gingivalis, the disk diffusion method was used to determine the inhibition zones at concentrations of 50, 100, 200, and 300 mg/㎖. To determine the minimum inhibition concentration (MIC), the final dose of LPEE was .2, .4, .8, 1.6, 2.5, and 5.0 mg/㎖, and the minimum bactericidal concentration (MBC) was determined based on the MIC results. To confirm the growth inhibitory effect of LPEE on both pathogens, the absorbance was measured at 600 nm after each incubation for 0, 3, 6, 12, and 24 hr at concentrations of .8, 1.6, 2.5, and 5.0 mg/㎖. Results : The cytotoxicity of LPEE was evaluated and the cell viability was more than 70 % at 400 mg/㎖. Therefore, concentrations of 50, 100, 200, and 300 mg/㎖ were used in this study. The antimicrobial effect against S. mutans was seen at 100 mg/㎖ and grew in a concentration-dependent manner, while P. gingivalis was effective at 50 mg/㎖ with the dose dependency. The MIC was .8 mg/㎖ for both strains, and the MBC was 1.6 mg/㎖ with the same results. The growth inhibitory effect of LPEE on S. mutans and P. gingivalis was observed, even at low concentrations. Conclusion : The antibacterial effect of LPEE was evaluated through the analysis of MIC, MBC, and growth inhibition effect on S. mutans and P. gingivalis, which suggests LPEE might have the possibility of utilization as a preventive and therapeutic composition for oral diseases.

• 한국식품저장유통학회지
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• 제8권2호
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• pp.217-223
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• 2001

The antimicrobial and glucosyltransferase(GTase) inhibition activity were searched for 30 species of various folk drugs and by products of food industry. Among them, two species, gallnut and red grape husk water extracts, were selected for the powerful antimicrobial and GTase inhibition activity. The polyphenol fractions of gallnut and red grape husk were showed very greater antimicrobial activity on both Gram(+) and (-), B. subtilis and E. coli. The minimum antimicrobial activity of gallnut polyphenol fraction were 1.0mg for B. subtilis and 3,0mg for E. coli. Red grape husk was 2.0mg for B. subtilis and 3.0mg for E coli. The polyphenol fractions of gall nut and red grape husk were showed powerful GTase inhibition activity. The concentrations of these fractions for 80% inhibition of GTase activity were 1.08$\times$10$\^$-3/mg/㎖ and 1.08$\times$10$\^$-2/mg/㎖, respectively. The most abundant compound in these fraction seems to be polyphenol derivatives. From these results, we think that the gallnut and the red grape husk polyphenol fraction had more antimicrobial and anti-plaque activities than artificial synthetic preservatives as an economic point of view.

• 한국식품영양학회지
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• 제21권1호
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• pp.15-21
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• 2008

In this study, the minimum inhibition concentration(MIC), growth inhibition activity, and colony forming inhibitory activity of water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae and Salmonella enteritidis were tested. The MICs of the water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 312.5 ppm, below 156.3 ppm, 625 ppm, 10,000 ppm, above 10,000 ppm, 10,000 ppm, above 10,000 ppm, above 10,000 ppm, 10,000 ppm, and above 10,000 ppm, respectively. The growth inhibition concentrations against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, and Klebsiella pneumoniae were 156.3 ppm, below 156.3 ppm, 625 ppm, 5,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, and 5,000 ppm, respectively. However, 10,000 ppm did not inhibit the growth of Salmonella enteritidis. Finally, the colony forming inhibitory activities against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 98.0%, 99.8%, 69.8%, 98.1%, 62.0%, 63.1%, 79.5%, 61.9%, 79.6%, and 0.0%, respectively.

• 대한임상검사과학회지
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• 제49권3호
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• pp.256-262
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• 2017

식물로부터 유래되는 휘발성 유기 화합물인 에센셜 오일은 인체에 약리효과를 나타낸다고 알려져 있다. 본 연구에서는 화농성 질환과 병독성 질환 비뇨기계통 감염에 나올 수 있는 병원성 세균 Staphylococcus aureus (그람양성알균), Escherichia coli (그람음성막대균), Pseudomonas aeruginosa (그람음성막대균, 극성단모균)을 대상으로 천연 허브 오일 중에 비교적 많이 알려져 있는 라벤더(lavender), 티트리(tea tree), 로즈마리(rosemary), 멜리사(melisa) 4종류의 단일 오일과 비교해, 티트리와 로즈마리, 멜리사를 블렌딩하였을 때 항균력이 상승되는 효과가 있는지 연구하였다. 그 결과 디스크 확산법에서 블렌딩 오일(티트리, 로즈마리, 멜리사)의 경우 단독의 허브오일보다 S. aureus에서18 mm, E. coli 에서 22 mm 와 P. aeruginosa는13 mm의 우수한 항균능력을 확인할 수 있었다. 뿐만 아니라 블렌딩 오일의 경우 최소억제농도(Minimum Inhibitory Concentrations, MIC) 분석에서 S. aureus, E. coli 에서는 0.3125%에서, P. aeruginosa는 1.25%에서 성장억제효과가 확인되었다. 따라서 본 실험에서는 블렌딩 오일이 Oxacillin과 로즈마리, 티트리보다 항균효과가 우수한 것으로 증명되어 단독의 허브오일보다 블렌딩 오일이 우수한 항균력을 나타나는 것을 확인할 수 있었다. 그러므로 허브의 블렌딩을 활용하면 다제 내성균에 대한 항균시너지효과를 발휘할 수 있음을 입증했을 뿐만 아니라 향후 천연보존제와 건강기능성 식품 및 화장품에 활용 가능성을 기대해본다.