• Biomedical Science Letters
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• v.30 no.1
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• pp.32-35
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• 2024

In vitro antimicrobial activities of hot water extracts of Chamaecyparis obtuse, for methicillin-resistant Staphylococcus aureus (MRSA) was compared to commonly used conventional antimicrobial agents. All MRSA was susceptible to linezolid or vancomycin, but also to erythromycin. MIC range and MIC₉₀ to erythromycin, clindamycin, levofloxacin, tetracycline for MRSA were each 4 ㎍/mL, 2 ~ >128 ㎍/mL, ≤0.06 ~ >128 ㎍/mL, 0.25 ~ >128 ㎍/mL, 0.25~64 ㎍/mL and 4 ㎍/mL, .128 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, 64 ㎍/mL. The hot water extracts of leaf of C. obtuse had the lowest MIC range, MIC₅₀, and MIC₉₀ (0.125 µL/mL) for the MRSA tested, and it was possible more potent than various conventional antimicrobial agents. Screen antibacterial drug candidate with high antibacterial activity such as derivatives of C. obtuse leaf extract such as terpinen-4-ol or using combined therapy with commercialized antibacterial agents will likely be helpful in treating refractory MRSA infections.

• Biomedical Science Letters
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• v.30 no.2
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• pp.96-99
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• 2024

In vitro antimicrobial activities of hot water extracts of Chamaecyparis obtuse, for clinical metallo-β-lactamase-Producing Pseudomonas aeruginosa (MBLPA.) was compared to commonly used conventional antimicrobial agents. All MBLPA was susceptible to colistin or amikacin, but also to imipenem 88.6%, meropenem 100%, piperacillin 85.7%, ceftazidime 97.1%, gentamicin 97.1%, and ciprofloxacin 100% were non-susceptible. MIC range to imipenem, meropenem, cefotaxime, ceftazidime, gentamicin, and ciprofloxacin for MBLPA were each 1 - >128 ㎍/mL, 4 - >128 ㎍/mL, 4 - >128 ㎍/mL, 8 - >128 ㎍/mL, 4 - >128, and 2- >128 ㎍/mL. MIC range to aztreonam for MBLPA were 1 - 128 ㎍/mL. MIC₉₀ to imipenem, meropenem, cefotaxime, ceftazidime, gentamicin, and ciprofloxacin for MBLPA were each 32 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, >128 ㎍/mL, and 128 ㎍/mL. MIC₉₀ to colistin and amikacin were each 1 ㎍/mL and 64 ㎍/mL. The hot water extracts of C. obtuse leaf had the lowest MIC range (0.25 - >0.5 μL/mL), MIC₅₀ (>0.5 μL/mL), and MIC₉₀ (>0.5 μL/mL) of the clinical MBLPA tested, and it was possible more potent than various conventional antimicrobial agents for MBLPA infection patients. Therefore, it suggested the possibility of using extract components of C. obtuse or their derivatives to treat MBLPA infection patients.

• Journal of Pharmacopuncture
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• v.10 no.3
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• pp.47-52
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• 2007

Objective This experimental study was performed to investigate the effect of Coptidis rhizoma extract compared with quantity on Staphylococcus aureus that induce keratitis. Methods Minimal inhibitory concentration(MIC) was measured by dropping to $50{\mu}l$　according to density Coptidis rhizoma extract(100%, 10%, 1%, 0.1%) compared with quantity(40g, 80g, 160g). Anti-bacterial potency was measured by the size of inhibition zone with change of volume. Results 1. MIC on Staphylococcus aureus in Coptidis rhizoma extract was showed anti-bacterial potency compared with quantity and density in 100% and 10% of all samples(40g, 80g, 160g). 2. MIC on Staphylococcus aureus in Coptidis rhizoma extract(40g, 80g, 160g) was showed anti-bacterial potency compared with quantity all samples($20{\mu}l,\;30{\mu}l,\;40{\mu}l,\;50{\mu}l$) in 100% density. 3. MIC on Staphylococcus aureus in Coptidis rhizoma extract(40g, 80g, 160g) was showed anti-bacterial potency compared with quantity all samples ($20{\mu}l,\;30{\mu}l,\;40{\mu}l,\;50{\mu}l$) in 100% density. Anti-bacterial potency of 80g Coptidis rhizoma extract decreased compared with 40g. Anti-bacterial potency of 160g Coptidis rhizoma extract decreased compared with 40g in $20{\mu}l,\;30{\mu}l$. Conclusions Coptidis rhizoma extract was showed anti-bacterial potency compare with quantity and density. In herbal drug, antibacterial potency compare with quantity and density must be studied.

• Korean Journal of Clinical Pharmacy
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• v.7 no.1
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• pp.40-44
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• 1997

Helicobacter pylori(HP) has been implicated as the cause of acute and chronic gastritis, peptic ulcer, and gastric carcinoma. To date the most successful treatment in eradicating HP is known to be the combination of two or more antibiotics with an anti-ulcer drug. In this study, in vitro antimicrobial activity against two was assessed, when proton pump inhibitors (PPIs), omeprazole and lansoprazole, were added to antibiotics at different concentrations. The assays in the absence of PPIs gave minimum inhibitory concentration(MIC) value of 0.63 mg/l for amoxicillin, 4 mg/l for tetracycline, 0.08 mg/l for clarithromycin and 0.16 mg/l for azithromycin. At the concentrations of 125 mg/l, 25 mg/1 and 0.5 mg/l of omeprazole, and the concentrations of 31.25 mg/l, 6.25 mg/l and 1 mg/l of lansoprazole, the MICs of clarithromycin and azithromycin were reduced by $50\%$. Also, lansoprazole at the highest concentration 31.25 mg/l reduced the MIC of amoxicillin by $50\%$, and omeprazole at the highest concentration of 125 mg/l reduced the MIC of tetracycline by $50\%$. In conclusion, the in vitro combination of PPIs and antibiotics led to improvement in the MIC of antibiotics against HP associated gastric disease.

• The Korean Journal of Mycology
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• v.43 no.2
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• pp.112-117
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• 2015

To investigate the changes of the resistance to prochloraz of Fusarium species causing bakanae disease, Fusarium isolates were collected from various regions in Korea, and pathogenicity tests were performed using rice seeds. Minimum inhibitory concentration (MIC) and effective concentration of 50% ($EC_{50}$) values of isolates were determined using the agar dilution method. High frequency distribution of MIC values of prochloraz against isolates collected in 2006~2007 and 2013~2014 years were $3.125{\sim}6.25{\mu}g/mL$ and $6.25{\sim}12.5{\mu}g/mL$, respectively. The mean $EC_{50}$ value of isolates increased from $0.3142{\mu}g/mL$ in 2006~2007 to $0.8124{\mu}g/mL$ in 2013~2014. Based on the $EC_{50}$ value of isolates collected in 2006~2007, the resistant baseline of prochloraz was determined as $0.6{\mu}g/mL$. Compared with the ratio of resistant isolates in 2006~2007, the ratio of resistant isolates in 2013~2014 increased from 6.5% to 41.6%.

• YAKHAK HOEJI
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• v.50 no.1
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• pp.15-20
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• 2006

Puerarin and daidzin have been isolated from Puerariae thunbergiana Benth. Structures were determined by spectroscopic methods. Compounds showed weak antimicrobial activity against S. mutans, S. epidermidis, S. aureus, and C. albicans (MIC, $800{\mu}g/ml$). However, these compounds were not antioxidative. Puerariae thunbergiana Benth. extracts against microorganisms were evaluated in terms of the minimum inhibitory concentrations (MIC). In general, C. albicans was stronger antimicrobial activity than the other microorganisms. The antioxidative activity of was observed in the etyl acetate extract ($IC_{50},\;119.87{\pm}0.16\;{\mu}g/ml$). The DPPH radical scavenging effect ($IC_{50},\;1,673.3{\pm}0.54\;{\mu}M$) of the puerarin was comparable with that of synthetic antioxidant, BHA $(IC_{50},\;88.39{\pm}1.1){\times}10^{3}{\mu}M$. These results suggest that puerarin and daidzin have a potential antimicrobial activity.

• BMB Reports
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• v.50 no.12
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• pp.597-598
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• 2017

Mitochondria have evolutionarily, functionally and structurally distinct outer- (OMM) and inner-membranes (IMM). Thus, mitochondrial morphology is controlled by independent but coordinated activity of fission and fusion of the OMM and IMM. Constriction and division of the OMM are mediated by endocytosis-like machineries, which include dynamin-related protein 1 with additional cytosolic vesicle scissoring machineries such as actin filament and Dynamin 2. However, structural alteration of the IMM during mitochondrial division has been poorly understood. Recently, we found that the IMM and the inner compartments undergo transient and reversible constriction prior to the OMM division, which we termed CoMIC, ${\underline{C}}onstriction$ ${\underline{o}}f$ ${\underline{M}}itochondrial$ ${\underline{I}}nner$ ${\underline{C}}ompartment$. In this short review, we further discuss the evolutionary perspective and the regulatory mechanism of CoMIC during mitochondrial division.

• Korean Journal of Microbiology
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• v.29 no.6
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• pp.353-360
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• 1991

5-substituted uridine(I,Br,Cl), 5'-amino-5'-deoxyuridine conjugates of amino acid, peptide and penicillin G, 5'-monophosphate uridine derivatives and 5'-monophosphate-fatty acid detrivatives were chemically synthesized. Their biological activities were determined as MIC and IC/sub 50/ unit against various pathogenic microorganisms in vitro. 5'-amino-5'-deoxyuridine-cyclo(Phe-Asp)(23), 5-iodo-5'-amino-deoxyuridine-penicillin G(26) were the most efficient; their IC/sub 50/ against L5178Y murine lymphoma cell was 6.5 h/ml, MIC against S. aureus (+) and E. coli (-) was 6.25 g/ml. MIC of 5-bromo-2', 3'-O-isopropylideneuridine(6) against Trichophyton rubrum was 0.2 g/ml. And 5'-monophosphate derivatives are more active than simple uridine derivatives, suggesting other modified nucleoside 5'-phosphate may be worthwhile examing further as a new prodrugs.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1740-1745
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• 2004

In order to evaluate the in vitro synergic effect of Eunkyo-san, with quinolone antibiotics, rufloxacin (RUFX), the minimal inhibitory concentration (MIC), MIC50 and MIC90 of single use of quinolones and concomitant treatment with Eunkyo-san against 9 strains of aerobic gram positive bacteria. The obtained results were as follows : In the case of aerobic gram positive bacteria, the MIC, MIC50 and MIC90 against Staphylococcus aureus, Staphylococcus aureus smith, Staphylococcus epidermidis, Staphylococcus pyogens, Streptococcus pneumoniae Type Ⅰ, Type Ⅱ and Type Ⅲ was significantly decreased in concomitant treated groups with Eunkyo-san compared to those of single treated groups of RUFX, respectively. However, no significant changes were demonstrated against Bacillus subtilis and Enterococcus faecalis. In conclusion, the in vitro antibacterial activity of RUFX were increased against some strains of aerobic gram positive strains, especially, pneumococcus such as Staphylococcus and Streptococcus by concomitant use of Eunkyo-san.

• The Journal of Internal Korean Medicine
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• v.26 no.3
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• pp.521-532
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• 2005

Objectives & Methods : In order to evaluate the in vitro synergic effects or Eunkyo-san which is a traditional poly-herbal formula that has been used in the treatment of respiratory diseases in oriental medicine, and quinolone antibiotics, rufloxacin (RUFX) and iprofloxacin(CPFX), experimentation was designed to determine minimal inhibitory concentration(MIC), $MIC_{50}\;and\;MIC_{90}$ of single use of quinolones and concomitant treatment with Eunkyo-san against 5 strains of aerobic gram negative bacteria, Escherichia coli, Klebsiella peumoniae, Hemophilus influenzae, Citrobacter freundii and Pseudomonas aeruginosae. Result : In the case of aerobic gram negative bacteria, the MIC, $MIC_{50}\;and\;MIC_{90}$ against Klebsiella peumoniae and Citrobacter freundii significantly decreased in concomitant-treated groups with Eunkyo-san compared to those of single-treated groups of RUFX and CPFX, respectively. However, no significant changes were demonstrated against Echerichia coli, Hemophilus influenzae and Pseudomonas aeruginosae. Conclusion : According to these results, concomitant use of Eunkyo-san against some strains of aerobic gram-negative bacteria dramatically increases in vitro antibacterial activity of RUFX and CPFX, and the increase and selectivity of antibacterial activities against these strains is attributable to Eunkyo-san, and not RUFX or CPFX activity.