• Journal of Microbiology and Biotechnology
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• 제28권7호
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• pp.1209-1216
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• 2018

This study aimed to evaluate the antimicrobial activity of 2-phenylethynyl-butyltellurium (PEBT) in Escherichia coli and the relation to its pro-oxidant effect. For this, we carried out the disk diffusion test, minimum inhibitory concentration (MIC) assay, and survival curve analysis. We also measured the level of extracellular reactive oxygen species (ROS), activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), and level of non-protein thiols (NPSH). PEBT at 1.28 and 0.128 mg/disk exhibited antimicrobial capability in the disk diffusion test, with an MIC value of 1.92 mg/ml, whereas PEBT at 0.96, 1.92, and 3.84 mg/ml inhibited bacterial growth after a 9-h exposure. PEBT at 3.84, 1.92, and 0.96 mg/ml increased extracellular ROS production, decreased the intracellular NPSH level, and reduced the SOD and CAT activities. Glutathione or ascorbic acid in the medium protected the bacterial cells from the antimicrobial effect of PEBT. In conclusion, PEBT exhibited antimicrobial activity against E. coli, involving the generation of ROS, oxidation of NPSH, and reduction of the antioxidant defenses in the bacterial cells.

• 치위생과학회지
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• 제18권3호
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• pp.147-154
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• 2018

This study aimed to evaluate the antimicrobial effects of Acanthopanax sessiliflorum fruit (ASF; Ogaza) extracts on Streptococcus mutans and Streptococcus sobrinus, which are agents that cause dental caries, and on Streptococcus mitis and Streptococcus salivarius, the microbial flora of the oral cavity. The ASF extracts obtained using 70% ethanol were fractionated in the order of ethyl acetate and n-Butanol, concentrated under reduced pressure, and lyophilized to give powdery solvent extracts. The antimicrobial activity of ASF extracts from each solvent was examined using the disk diffusion method. As a result, only those extracts obtained using an ethyl acetate solvent showed antimicrobial activity. These extracts were selected, and the minimum inhibitory concentration was measured by disk diffusion method at various extract concentrations. Results showed a minimum inhibitory concentration of 32 mg/ml. The viable cell count was measured to confirm the minimum bactericidal concentration. Results showed a minimum bactericidal concentration of 64 mg/ml. In the cytotoxicity test using normal human dermal fibroblast cells, the absorbance value of the test group was similar to that of the control group at 0.64, 1.28, and 6.4 mg/ml. The bacteria and their colonies were examined using a scanning electron microscope. Boundaries between the antimicrobial activity region and non-antimicrobial activity region were observed around the paper disk, which was immersed in the extract with 32 mg/ml concentration. Bacterial colonization was not observed in the area with antimicrobial activity. This finding suggests that ASF extracts can inhibit the growth of some microorganisms in the oral cavity, in addition to the effects of these extracts known to date. In particular, ASF extracts may be used as a preparation for preventing dental caries by adding the extract to the toothpaste or oral mouthwash.

• Journal of Korean Neurosurgical Society
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• 제63권1호
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• pp.45-55
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• 2020

Objective : Fibrin sealants have been used for hemostasis, sealant for cerebrospinal fluid leakage, and adhesive barrier in neurosurgery. Further, as its clinical use and role of an effective drug delivery vehicle have been proposed. This study was performed to measure antibacterial activity and continuous local antibiotic release from different concentrations of vancomycin-impregnated fibrin sealant in vitro. Methods : Antibacterial activity was investigated by disk diffusion test by measuring the diameter of the growth inhibition zone of bacteria (methicillin-resistant Staphylococcus aureus, ATCC29213) from vancomycin-embedded fibrin sealant disc diluted at five different concentrations (C1-C5; 8.33, 4.167, 0.83, 0.083, and 0.0083 mg/disc, respectively). Continuous and conditioned release of vancomycin concentration (for 2 weeks and for 5 days, respectively) were also measured using high-performance liquid chromatography (HPLC) method. To mimic the physiologic wound conditions with in vitro, conditioned vancomycin release in phosphate buffer solution (PBS) was measured and replaced PBS for five consecutive days, half a day or completely daily. Results : In the disk diffusion test, the mean diameters of bacterial inhibition zone were 2.54±0.07 cm, 2.61±0.12 cm, and 2.13±0.15 cm (C1, C2, and C3 respectively) but 1.67±0.06 cm and 1.23±0.15 cm in C4 and C5, respectively. Continuous elution test elicited the peak release of vancomycin from the fibrin sealant at 48 hours, with continued release until 2 weeks. However, conditioned vancomycin release decreased to half or more on day 2, however, the sustainable release was measured over the therapeutic dose (10-20 ㎍/mL) for 5 days and 4 days in assays of half and total exchange of PBS. Conclusion : This study suggests that fibrin sealant can provide an efficient vehicle for antibiotic drug release in a wide range of neurosurgical procedures and the safe and effective therapeutic dose will be at the concentration embedded of 4.167 mg/disc or more of vancomycin.

• 한국미생물·생명공학회지
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• 제34권4호
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• pp.342-351
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• 2006

병원내 항생제 다제 내성을 일으키는 CTX-M형 ESBL을 생성하는 E. coli와 Klebsielia pneumoniae의 생성현황을 조사하고 이들 균주로 인한 감염증치료와 역학적 조사연구에 도움이 되고자 효소의 유전형을 규명하였다. 2005년 7월-12월에 부산에 소재하고 있는 2개의 종합병원에서 분리된 E. coli와 K. pneumoniae 각각 153주, 52주를 수집하였다. 그 중에서 ESBL을 생성 하는 균주를 검출하기 위해 Double disk synergy test를 시행하여서 E. coli 23주와 K. pneumoniae 13주를 분리하였다. 균주의 동정은 Vitek system GNI card(bioMerieux Vitek Inc., Hazelwood, Mo., U.S.A.)로 확인하였고, 항생제감수성시험은 disk diffusion method 와 agar dilution method를 사용하였다. 분리된 균주들의 내성을 일으키는 ESBL유전형을 규명하기 위하여 Isoelectric focusing(IEF), polymerase chain reaction test, DNA sequencing을 시행하였다. A병원의 13주와 B병원의 10주로 총 23주의 E. coli(15.0%)와 A병원의 7주와 B병원의 6주로 K. pneumoniae 13주(25.0%)가 double disk synergy test 양성으로 ESBL 생성균주로 판정하였다. ESBL 생성 36균주를 대상으로 bla$_{TEM}$, bla$_{SHV}$, bla$_{CTX-M}$ 유전자 검출을 위한 PCR을 시행한 결과 bla$_{TEM}$ 유전자는 13주(36.1%), bla$_{SHV}$ 유전자는 13주(36.1%), bla$_{CTX-M}$ 유전자는 32주(88.9%)가 양성반응을 보여서 bla$_{CTX-M}$ 유전자를 가진 균주가 가장 많이 나타났다. 그리고, bla$_{TME}$, bla$_{SHV}$ 두 가지 유전자를 가지고 있는 균주는 1주(2.8%)만 나타났고 bla$_{TEM}$, bla$_{CTX-M}$두 가지 유전자를 가지고 있는 균주는 9주(25.0%), bla$_{SHV}$, bla$_{CTX-M}$ 두 가지 유전자를 가지고 있는 균주가 10주(27.8%)로 나타나 bla$_{CTX-M}$을 포함하는 복합유전자가 많이 증가함을 알 수 있었다. 또한 CTX-M형 ESBL을 생성하는 E. coli와 K. pneumoniae에 대한 cefutaxime의 MIC는 256 $\mu$g/m1 이상으로 ceftazidime의 16-256 $\mu$g/mL 이상보다 높은 분포를 보였다. 즉, CTX-M형 ESBL 유전자를 지닌 균주에 대한 cefotaxim의 MIC는 ceftazidime의 MIC에 비해서 상대적으로 높은 양상을 보였다. 이러한 결과는 국내의 대학병원 뿐 만 아니라 일반종합병원에서도 CTX-M형 ESBL 생성 E. coli와 K. pneumoniae가 존재하며 확산 중임을 시사한다. 앞으로 CTX-M형 ESBL의 만연과 변종 CTX-M형 ESBL의 출연을 감시하기 위한 정기적인 연구와 조사가 필요한 것으로 생각한다.

• 한국동물위생학회지
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• 제36권4호
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• pp.297-301
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• 2013

The present study was to investigate anti-microbial effects of curcumin on major bacterial pathogens for farmed fish, such as Aeromonas hydrophila, A. salmonicida subsp. masoucida, A. salmonicida subsp. salmonicida, Edwardsiella tarda, Vibrio vulnificus, V. paraheamolyticus using disk diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests. In disc diffusion test, curcumin exhibited concentration-dependent antimicrobial activities to all bacteria pathogens used in the study. Antimicrobial effects of curcumin was found differently depending on bacterial species when determined by MIC or MBC tests. For examples, E. tarda and A. hydrophila was respectively the most sensitive bacterium for bacteriostatic and bacteriocidal effect of curcumin. Collectively, curcumin could be a potential natural drug for controlling pathogenic bacteria in the aquaculture industry.

• 대한화학회지
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• 제55권3호
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• pp.400-404
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• 2011

홍화는 예로부터 '사람의 건강에 도움이 된다'고 해서 '잇꽃'으로 불려져 왔으며 동의보감에서는 꽃잎이 홍색을 나타내기 때문에 홍화(紅花)로 소개되어 있다. 예로부터 홍화는 꽃잎을 압착후 정제된 색소를 이용하여 옷감에 천연색소를 입히는 염료와 연지의 재료로 사용되기도 하였다. 현대에 와서는 홍화의 주성분인 폴리페놀 화합물(Polyphenol cocktail) 성분이 건강식품업계에서 항노화 및 항산화물질로 알려지면서 관심의 대상이 되고 있다. 금번연구에서는 홍화의 주성분인 폴리페놀 화합물이 청소년기 혹은 장년기에서도 고민거리가 되고 있는 여드름균의 생성을 억제시킬 수 있는 항균, 항염효능이 있음을 DDT(Disk Diffusion Test) assay, MTT assay, NF-${\kappa}$B Luciferase activity inhibition assay의 in vitro법으로 확인하고 더불어 인체안면에 대한 임상시험에 사용할 세안화장품 제형의 화장비누 시제품을 제조하여 여드름피부의 개선 효과가 있음을 시험하고자 한다. 또한 이번 연구는 여드름용 화장비누 개발에 진일보하여 약용화장품 산업의 발전에 기여할 것임을 확신한다.

• 한국미생물·생명공학회지
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• 제40권4호
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• pp.380-388
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• 2012

북극 지의류로부터 서로 다른 5종의 극지 미생물을 분리하였고, 그들의 생리활성 물질들은 아세톤, 물, 클로로포름, 다이에틸에테르, 에탄올, 에틸아세테이트, 메탄올 및 페트롤륨 에테르 등 다양한 용매를 이용하여 균 배양액으로부터 추출되었다. 이러한 추출물들의 항균성은 Staphylcoccus aureus, Bacillus subtilis, Micrococcus luteus, Enterobacter cloacae, Pseudomonas aeruginosa 및 Escherichia coli 등 6종의 병원체에 대한 디스크 확산법과 최소억제농도 측정법에 의해 조사되었다. 여러 추출 샘플 중, Burkholderia sordidicola S5-$B^T$ (KOPRI 26644) 유사미생물 종의 에틸아세테이트 추출물이 표적박테리아에 대한 높은 항균활성을 나타내었다(억제대, 7-10 mm; 최소억제농도, $57.5{\rightarrow}1000{\mu}g/ml$). 또한, 다양한 추출 용매 중, 클로로포름 추출물에서 약하지만 분명한 활성을 나타내었다.

• 대한통합의학회지
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• 제7권2호
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• pp.141-151
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• 2019

Purpose : Hypochlorous acid (HOCl), a major inorganic bactericidal compound of innate immunity, is effective against a broad range of microorganisms. In particular, HOCl is well-known as a non-antibiotic antimicrobial substance. However, effects of HOCl as an antimicrobial agent are still needed to study these functions against various specific type of microorganisms. In this study, we investigated the antimicrobial effect of hypochlorous acid (HOCl) in S. mutans and A. actinomycetemcomitans to cause dental caries and periodontal disease. Experiments were conducted to observe whether HOCl become effective replacement of disinfectant. Methods : To observe antimicrobial effect of HOCl, stabilized HOCl is prepared in the form of a physiologically balanced solution in pre-conditioned and post-conditioned HOCl solution. As a control, commercially available disinfectant MAXCLEAN was used as positive control. Moreover, S. mutans and A. actinomycetemcomitans distribution in gagrin, filtered tap water, and culture media. Cell viability were measured by viable cell count methods and disk diffusion test. Results : Our results showed that treatment of HOCl have no effect against antimicrobial effect compare to control group especially gagrin in disk diffusion test. HOCl tended to reduced viability against S. mutans in group of post-conditioned than pre-conditioned of HOCl solution however, there was no significant difference as well as no effect in A. actinomycetemcomitans. Conclusion : HOCl showed tendency to reduce viability against S. mutans in group of post-conditioned of HOCl solution and no effect of antimicrobial effect. Although HOCl is well known as effective against a broad range of microorganisms, HOCl seems to have diversity following type of species to be used as antimicrobial drug following our results. Therefore, it is necessary to be rigidly controlled and regulated in using HOCl solution clinically.

• Archives of Pharmacal Research
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• 제24권6호
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• pp.590-596
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• 2001

A new extended-spectrum ${\beta}-lactamase$ with an isoelectric point (pl) of 6.2 was detected in Klebsiella pneumoniae Fl 61 that was isolated from a patient with infection. This strain was highly resistant to the third or fourth generation cephalosporins such as cceftazidime ceftriaxone, cefoperzaone, and cefpirome. Analysis of this strain by the double disk diffusion test showed synergies between amoxicillin-clavulanate (AMX-CA) and cefotaxime, and AMX-CA and aztreonam, which suggested that this strain produced a extended-spectrum ${\beta}-lactamase$ (ESBL). Cenetic analysis revealed that the resistance was due to the presence of a 9.4-kb plasmic, designated as pkpl 61, encoding for new ${\beta}-lactamase$ gene (bla). Sequence analysis showed that a new bla gene of pkpl 61 differed from $bla_{TEM-1}$ by three mutations leading to the following amino acid substitutions: $Val_{84}{\rightarrow}lie,{\;}Ala_{184}{\rightarrow}Val,{\;}and{\;}Gly_{238}{\rightarrow}Ser$. These mutations have not been reported previously in the TIM type ${\beta}-lactamases$ produced by clinical strains. The novel ${\beta}-lactamase$ was overexpressed in E. coli and purified by ion exchange chromatography on Q-Sepharose and CM-Sepharose, and then further purified by gel filtration on Sehadex G-200. The catalytic activity of th8 purified ${\beta}-lactamase$ was confirmed by the nitrocefin disk.

• Natural Product Sciences
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• 제13권1호
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• pp.85-89
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• 2007

To determine whether the essential oil from Coriandum sativum and its main component, linalool, exhibit antifungal activity, we employed a broth dilution assay and disk diffusion test using common pathogenic Candida and Trichophyton species. Both coriander oil and linalool significantly inhibited growth of the tested fungi, with minimal inhibitory concentrations (MICs) in the range of $0.03{\sim}2mg/ml$. Furthermore, in a checkerboard titer test, both the oil fraction and linalool exhibited synergism when combined with ketoconazole, with resultant FICIs ranging from 0.06 to 0.53. Notably, hyphal formation in C. albicans cells was obviously inhibited by C. sativum essential oil in this experiment.