• 한국식품영양과학회지
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• 제31권5호
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• pp.899-904
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• 2002

알로에 및 프로폴리스 추출물과 그 혼합물의 구강 내 병원균에 대한 항균효과 및 상호작용효과를 검색하였다. 알로에 ethanol 추출물 (AE)의 구강 병원균에 대한 최소저해농도는 S. mutans, C. albicans, E. coli에 대해서는 250$\mu\textrm{g}$/mL, E. fae-calis는 270$\mu\textrm{g}$/mL로 나타났다. 프로폴리스 ethanol 추출물(PE)의 경우에는 S. mutans에 대해서는 20 $\mu\textrm{g}$/mL, E. hirae, C. albicans, E. coli에 대해서는 20$\mu\textrm{g}$/mL, E. faecalis에 대해서는 40$\mu\textrm{g}$/mL로 나타났다. 수지 및 밀납성분을 제거한 분획(PW)의 S. mutans, E. hirae, C. albicans, E. coli의 최소저해농도는 70$\mu\textrm{g}$/mL로, PE 분획보다 낮은 항균활성을 보였으며, E.faecalis의 경우에는 18$\mu\textrm{g}$/mL로 PE분획보다 높은 항균활성을 보였다. AE 및 PE의 혼합물의 항균효과를 측정한 결과, S. mutans, E. faecalis, E. hirae, C. albicans에 대하여는 상승효과 (FICI=0.375)가 있었으며, AE 및 PE의 각각의 MIC의 1/2 이하의 모든 농도범위에서 상승효과(FICI$\leq$0.5)가 있었다. 그러나 E. coli에 대하여는 AE 및 PE의 혼합에 의한 상승효과가 없었다(FICI=1.0). 또한, AE 및 PW의 혼합물의 항균효과를 측정한 결과, S. mutans, E. faecalis, E. hirae, C. albicans에 대하여는 상승효과가 적은 것 (FICI=0.75)으로 나타났다. 즉, 사용된 구강 병원균주 중에서 E. coli를 제외한 모든 균주들에 대하여 PE 및 PW는 AE의 항균효과를 강화시키는 것으로 나타났다.

• 대한약침학회지
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• 제25권2호
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• pp.101-105
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• 2022

Objectives: This study aims to determine the Fractional Inhibitory Concentration Index (FICI) of combinations of Melastoma malabathricum leaf fraction with ciprofloxacin or gentamicin against pathogenic bacteria, Escherichia coli, Staphylococcus aureus, and Bacillus cereus, isolated from Diabetic Foot Ulcer (DFU) patients. Methods: We tested concentrations of 45%, 55%, 65%, and 75% of gentamicin and ciprofloxacin using dilution and agar diffusion methods. The combination of M. malabathricum leaf extract with these antibiotics was tested in vitro against all three bacteria. Results: The combination of M. malabathricum leaf extract and ciprofloxacin gave a FICI value of 0.5, indicating synergistic antibacterial activity against the test bacteria. Conclusion: The results show that the antibacterial effect of a combination of high doses of the leaf extract with either antibiotic is greater than that of the leaf extract and the antibiotics in single use.

• Archives of Pharmacal Research
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• 제17권6호
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• pp.438-442
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• 1994

Antimicrobial activity of GL (the aqueous extract from the carpophores of Ganoderma lucidum ($F_RK_{KARST}$) was tested in vitro aginst Gram positive and Gram negative bacteria by serial broth dilution method, and the antimicrobial activity was expressed by minimal inhibitory concentration (MIC). Among fifteeen species of bacteria tested, the natimicrobial activity of GL was of antimicrobial combinations of GL with four kinds of antibiotics (ampicilin, cefazolin, oxytet-racycline and chloramphenicol), the fractional inhibitory concentraction index (FICI) was determined by checkerboard assy for each stain. The antimicrobial combinations of GL with four antibiotics resulted in additive effect in most instances, synergism in two instances, and antagonism in two instances. Synergism was obversed when GL was combined with cefazolin against Bacillus subtilis and Klebsiella oxytoca.

• 한국균학회지
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• 제49권4호
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• pp.539-545
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• 2021

한국의 무화과나무 모무늬잎마름 증상에 관여하는 한 균주의 Cercospora류 곰팡이가 형태적으로는 Passalora속에 속하지만 계통학적으로는 Pseudocercospora속에 속한다고 알려져 있다. 이 문제를 해결하기 위하여, 6점의 시료를 현미경으로 검경하였으며 두 균주를 염기서열 분석하였다. 그 결과, 이들 시료의 곰팡이는 형태적으로는Passalora bolleana와 일치하였다. ITS와 LSU 염기서열을 분자계통학적으로 분석한 결과 이들 두 균주가 Pseudocercospora속 집락에 위치하였다. 결과적으로, 한국 유래의 세 균주(본 연구의 두 균주와 이전의 한 균주)와 루마니아 유래의 한 균주는 모두 Pseucocercospora bolleana로 동정되었다. 추가적으로, 대만과 한국에서 무화과나무 점무늬병균으로 알려진 Pseudocercospora fici-caricae와도 비교하고 토의하였다.

• 약학회지
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• 제38권6호
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• pp.742-748
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• 1994

As part of our search for less toxic antimicrobial agents from natural resources, the carpophores of Elfvingia applanata$(P_{ers}.)K_{ARST}.$ was extracted with hot water. EA, the aqueous extract from the carpophores of E. applanata, was lyophilized and a dark brownish powder was obtained. Antimicrobial activity of EA was tested in vitro against Gram positive and Gram negative bacteria by serial broth dilution method, and the antimicrobial activity was expressed by minimal inhibitory concentration(MIC). Among fourteen species of bacteria tested, the antimicrobial activity of EA was the most potent against Proteus vulgaris showing MIC of 1.250 mg/ml. To investigate the effect of antimicrobial combinations of EA with four kinds of antibiotics(ampicillin, cefazolin, oxytetracycline and chloramphenicol), the fractional inhibitory concentration index(FICI) was determined by checkerboard assay for each strain. The antimicrobial combinations of EA with four kinds of antibiotics resulted in synergism in four instances, but no antagonism was observed. Four instances of synergism were observed when EA was combined with ampicillin against Micrococcus luteus, with cefazolin against Bacillus subtilis, with cefazolin against Micrococcus luteus and with oxytetracycline against Staphylococcus aureus.

• 약학회지
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• 제40권6호
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• pp.653-658
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• 1996

As part of our search for less toxic antimicrobial agents from natural resources. rutin was isolated from Sophora japonica and then hydrolyzed to quercetin. Antimicrobial activity of quercetin was tested in vitro against five kinds of gram positive and ten kinds of gram negative bacteria by serial broth dilution method. Among fifteen kinds of bacteria tested, the antimicrobial activity of quercetin was the most potent against Proteus vulgaris showing minimal inhibitory concentration(MIC) of 125 ${\mu}$g/ml. To investigate the effect of antimicrobial combinations of quercetin with four kinds of antibiotics (ampicillin, cefazolin, oxytetracycline and chloramphenicol). the fractional inhibitory concentration index (FICI) was determined by checkerboard assay for each strain. The antimicrobial combinations of quercetin with four kinds of antibiotics resulted in synergism in one instance, additive effect in four instances, but no antagonism was observed.

• 대한약침학회지
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• 제19권4호
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• pp.312-318
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• 2016

Objectives: Bacterial resistant infections have become a global health challenge and threaten the society's health. Thus, an urgent need exists to find ways to combat resistant pathogens. One promising approach to overcoming bacterial resistance is the use of herbal products. Green tea catechins, the major green tea polyphenols, show antimicrobial activity against resistant pathogens. The present study aimed to investigate the effect of catechins, green tea extract, and methylxanthines in combination with gentamicin against standard and clinical isolates of Staphylococcus aureus (S. aureus) and the standard strain of Pseudomonas aeruginosa (P. aeruginosa). Methods: The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values of different agents against bacterial strains were determined. The interactions of green tea extract, epigallate catechin, epigallocatechin gallate, two types of methylxanthine, caffeine, and theophylline with gentamicin were studied in vitro by using a checkerboard method and calculating the fraction inhibitory concentration index (FICI). Results: The MICs of gentamicin against bacterial strains were in the range of $0.312-320{\mu}g/mL$. The MIC values of both types of catechins were $62.5-250{\mu}g/mL$. Green tea extract showed insufficient antibacterial activity when used alone. Methylxanthines had no intrinsic inhibitory activity against any of the bacterial strains tested. When green tea extract and catechins were combined with gentamicin, the MIC values of gentamicin against the standard strains and a clinical isolate were reduced, and synergistic activities were observed (FICI < 1). A combination of caffeine with gentamicin did not alter the MIC values of gentamicin. Conclusion: The results of the present study revealed that green tea extract and catechins potentiated the antimicrobial action of gentamicin against some clinical isolates of S. aureus and standard P. aeruginosa strains. Therefore, combinations of gentamicin with these natural compounds might be a promising approach to combat microbial resistance.

• 한국미생물·생명공학회지
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• 제38권4호
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• pp.405-413
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• 2010

무화과는 뽕나무 과에 속하며 세계에서 가장 오래된 과일 중 하나이고, 국내에서는 주로 소화장애, 염증성궤양 그리고 가려움증 등에 사용되어 왔다. 본 연구에서는 무화과 잎을 메탄올로 추출한 후 임상진료실에서 분리된 메티실린 내성 황색포도상구균(MRSA)에 대한 항균활성을 보았다. 그 결과 분리된 MRSA 1-20에서 최소억제농도 (MIC)는 2.5 mg/mL에서 20 mg/mL 농도로 측정되었으며, 최소살균농도(MBC)는 5 mg/mL에서 20 mg/mL 농도로 관찰되었다. Oxacillin이나 ampicillin과 병용투여 시 4-8배 이상의 MIC/MBC농도가 감소되었으며, FICI 값도 0.0375-0.5이하로 병용효과를 나타내었다. 더불어 메탄올추출물 단독 사용시 보다 항생제와 병용투여 시 빠른 사멸효과를 보였다. 결론적으로 무화과 잎이 메티실린 내성 황색포도상구균에 항균활성을 나타냄을 확인하였으며, 메티실린 내성 황색포도상구균 감염에 천연 치료제로서의 가능성을 확인하였다.

• Archives of Pharmacal Research
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• 제27권3호
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• pp.295-299
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• 2004

The antifungal activities of the essential oil from Agastache rugosa and its main component, estragole, combined with ketoconazole, one of the azole antibiotics commonly used to treat infections caused by Trichophyton species, were evaluated in this study. The combined effects were measured by the checkerboard microtiter and the disk diffusion tests, against T. erinacei, T. mentagrophytes, T. rubrum, T. schoenleinii and T. soudanense. Susceptibility of the five Trichophyton species to the oil alone, or ketoconazole alone, differed distinctly. The fractional inhibitory concentration indices (FICI) of ketoconazole combined with estragole or A. rugosa essential oil, against the tested Trichophyton species, were between 0.05 and 0.27, indicating synergistic effects. These drug combinations exhibited the most significant synergism against T. mentagrophytes, with FICIs of 0.05 and 0.09 for estragole and the essential oil fraction from A. rugosa, respectively. Isobolograms based on the data from checkerboard titer tests also indicated significant synergism between ketoconazole and the Agastache oil fraction or estragole, against the Trichophyton species evaluated. Trichophyton susceptibility to ketoconazole was significantly improved by combination with the Agastache rugosa oil fraction or its main component, estragole.

• Bulletin of the Korean Chemical Society
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• 제20권4호
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• pp.411-416
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• 1999

A new kind of differential flow induced chemical wave is introduced by theoretical calculation. A differential flow between the counter acting species of a dynamical activator-inhibitor system may destabilize its homogeneous reference state and cause the medium to self-organize into a pattern of travelling waves through the differential flow instability (DIFI). In a chemical system, also, the differential bulk flow may change the dynamics of the system, thus it has been refered to as the differential flow induced chemical instability (DIFICI). For DlFICI experiments, one directional flow has been commonly employed, resulting in periodic wave patterns generally. In this study, we considered two directional flow for the DIFICI wave by exchanging artificially the flow direction at some period.