• 미생물학회지
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• 제52권3호
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• pp.327-335
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• 2016

본 연구에서는 신규 Amycolatopsis 균주 KCTC 29142를 분리하여 형태학적 관찰, 계통분석 및 화학분류학적 분석 등 다상 분류분석을 통해 분석하였다. KCTC 29142 균주의 에틸아세테이트추출물은 강한 항균활성을 나타났고, 활성물질은 철 이온 킬레이트 물질인 siderochelin A로 동정되었다. 본 연구에서 분리된 siderochelin A는 다제내성균인 Acinetobacter baumanii, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Staphylococcus aureus (VRSA), 및 Escherichia coli (E. coli)에 대해 강한 활성을 보였고, 임상에서 분리된 다제내성균에 대한 MIC를 결정하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제17권1호
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• pp.73-79
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• 2013

The fruit of the black raspberry (Rubus coreanus Miquel) has been employed in traditional medicine, and recent studies have demonstrated its measureable biological activities. However, the root of the black raspberry has not been studied. Therefore, in this study, we evaluated the anti-inflammatory and antibacterial properties of the root and unripe fruit polyphenols of the black raspberry. Both polyphenols proved to have anti-inflammatory activity as evidenced by the decreased nitric oxide (NO), cytokines (IL-$1{\beta}$, IL-6, and IL-10) and prostaglandin E2 ($PGE_2$) levels in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages. However, root polyphenols showed stronger anti-inflammatory activity than fruit polyphenols. LPS-induced mRNA and protein expressions of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 levels were also decreased, confirming the anti-inflammatory activity. Root polyphenols showed lethal activity against methicillin-resistant Staphy-lococcus aureus (MRSA), carbapenem-resistant Acinetobacter baumannii (CRAB), and Bacillus anthracis. In contrast, the black raspberry fruit did not demonstrate these properties. These data provide the first demonstration that black raspberry root has potential anti-inflammatory and anti-superbacterial properties that can be exploited as alternatives for use in the food and cosmetic industries and/or as pharmaceuticals.

• Tuberculosis and Respiratory Diseases
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• 제72권1호
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• pp.30-36
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• 2012

Background: Patients with ventilator-associated pneumonia (VAP) in intensive care unit (ICU) have a high mortality rate. The routine surveillance cultures obtained previously or an ATS guideline for hospital-acquired pneumonia was used in selecting initial antimicrobials. The object of this study was to compare the respiratory samples before VAP and bronchoalveolar lavage (BAL) culture. Methods: 54 patients underwent fiberoptic bronchoscopy to obtain BAL samples. We reviewed microbiologic specimen results of prior respiratory specimens (pre-VAP) and BAL. Results: Among 51 patients with 54 VAP episodes, 52 microorganisms of pre-VAP and 56 BAL samples were isolated. Pre-VAP included 21.2% of MRSA, and 32.6% of multidrug resistant-Acinetobacter baumannii (MDR-AB). BAL samples comprised 25.0% of MRSA, 26.7% of MDR-AB, 14.3% of Stenotrophomonas maltophilia and 3.6% of Klebsiella pneumonia in order. In pre-VAP samples compared to BAL samples, only 35.2% were identical. In BAL samples compared to pre-VAP samples obtained in 5 days before the onset of VAP, only 43.6% were identical. However, among BAL samples compared to pre-VAP samples obtained after more than 5 days, 13.3% were identical (p=0.037). Conclusion: Based on these data, pre-VAP samples obtained prior to 5 day onset of VAP may help to predict the causative microorganisms and to select appropriate initial antimicrobials.

• KSBB Journal
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• 제26권2호
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• pp.100-106
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• 2011

Strain BCNU 5011 was isolated from forest soil samples collected in the Taebaek mountain in the Gangwon province, Korea. The biochemical, physiological and 16S rRNA sequence analysis strongly indicated that this isolate was most closely related to Paenibacillus polymyxa. A maximum production level of antimicrobial substances of Paenibacillus sp. BCNU 5011 was achieved under aerobic incubation at $30^{\circ}C$ for 3 days in SST broth.Paenibacillus sp. BCNU 5011 showed a broad spectrum of activity against Gram positive and Gram negative bacteria, including methicllinresistant Staphylococcus aureus (MRSA). Paenibacillus sp. BCNU 5011 was also shown to inhibit the growth of different potential human pathogenic bacteria and fungi in vitro. Peptide extract showed better antimicrobial activity than solvent extracts. But active antimicrobial compounds might be included in both peptide extract and solvent extracts. Further separation, purification and identification of active principles leads project to develop antimicrobial agents and anti-MRSA agents.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1249-1250
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• 2015

We report a plasma-on-a-chip (POC) which provides a non-thermal atmospheric plasma for superbacteria infection treatment A three-electrode configuration allows an initiation carrier injection prior to a primary discharge, leading to a significant reduction in a breakdown voltage. A stable non-thermal argon plasma is generated using a pulsed glow discharge and inactivation of anti-biotic resistant bacteria, for example MRSA, is successfully demonstrated by exposing the bacteria to the argon plasma in a couple of minutes.

• Journal of Microbiology and Biotechnology
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• 제22권6호
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• pp.800-805
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• 2012

Licochalcone E was firstly isolated from licorice root in 2005, which belongs to the retrochalcone family. Studies on the biological activities of licochalcone E were in the initial stage. In the study, we demonstrated that licochalcone E has potent antimicrobial property against Staphylococcus aureus. Furthermore, via hemolysis, Western blot, and real-time RT-PCR assays, we have shown that subinhibitory concentrations of licochalcone E dose-dependently reduces the production of ${\alpha}$-toxin in both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). The data suggest that licochalcone E may deserve further investigation as a potential therapeutic against S. aureus infections, or the structure of licochalcone E may be used as a basis for chemical synthesis of novel anti-S. aureus compounds.

• 한국유기농업학회지
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• 제22권3호
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• pp.469-481
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• 2014

본 연구진은 신규 미생물인 Nocardia sp. CS682 균주에서 항균물질인 nargenicin을 확보하고, 그 유도체 5종을 확보하여 그람양성, 음성 및 다약제 내성균에 대한 항균 효능 및 LPS로 자극된 대식세포에서의 nitric oxide 생성 억제능을 확인하였다. Nargenicin 유도체들은 nargenicin 및 vancomycin에 비교하여 우수한 항균 활성을 보여주었으며, compound 4 및 5는 광범위한 항균 효능 외에 nitric oxide 생성 억제능을 보여 항균-항염효과를 가지는 dual effector로써 감염, 면역 질환에 응용 가능성을 시사하였다. Nargenicin 유도체들은 향후 염증반응에서의 면역 조절 기작에 대한 추가 연구가 필요할 것으로 사료된다.

• 생명과학회지
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• 제17권9호통권89호
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• pp.1278-1283
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• 2007

시중에서 사용되고 있는 일반 소독제를 대상으로 하여 병원 미생물의 내성 빈도를 검토한 결과는 약 30%였다. 그 중에서 푸드세프 (산화제 중 할로겐 계 소독약)와 동인테고 (양성 계면 활성제) 및 Iodo 175 (양성 계면 활성제)는 병원 미생물에 대해 낮은 감수성을 나타냈었을 뿐 아니라, 시험에 사용된 다른 소독제에 비하여 높은 내성 빈도를 나타내었다. 소독제 내성 균주를 사용해서 항생제 내성을 MIC test와 paper disc 방법으로 확인한 결과 30%의 내성 빈도를 나타내었다. 다른 항생제에 비해 aminoglycoside 계의 항생제인 gentamycin, kanamycin, streptomycin에서 높은 내성 빈도를 나타냄을 확인할 수 있었다. 본 연구실에서 제주도 손바닥 선인장으로부터 추출${\cdot}$분획한 MBT-01108 물질을 소독제와 항생제에 내성을 획득한 내성균에 상용했을 경우 내성이 생기지 않을 뿐 아니라, 내성균이 자라지 못하였다. 또한 현재 문제시되고 있는 다제 내성균인 MRSA, R-Pseudomonas aeruginosa, VRE, E. coli O157에 사용했을 경우에도 마찬가지의 결과를 얻을 수 있었다. 이상에서 살펴 본 바와 같이 손바닥 선인장에서 추출 ${\cdot}$ 분획한 MBT-01108 물질은 기존의 항생제와는 다른 기작으로 작용을 할 것으로 생각되고, 신규 항균 활성 물질의 약제 개발에 그 유용성이 매우 클 것으로 기대되며 여러 가지 항균성 생활 제품의 개발에도 유용할 것으로 기대된다.

• 생명과학회지
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• 제15권2호
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• pp.279-286
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• 2005

손바닥선인장 추출물은 한의학에서 항염증 작용, 화상, 부종, 소화 불량 등 몇 가지의 생리학적 기능이 확인되었다. 본 연구에서는 손바닥선인장 줄기를 메탄올을 이용하여 추출한 후 그 추출물을 이용하여 항균활성을 확인한 결과 병원균 등 일반 세균에서 항균활성을 확인하였다. 특히, 약제내성균 및 혐기성 균인 여드름 원인균 뿐만 아니라 효모, 곰팡이 등 진균류에서도 항균활성을 나타내어 넓은 항균 스펙트럼을 가지고 있음을 확인할 수 있었다. 또한 열 처리, 저장온도 및 저장기간이 항균활성에 영향을 미치지 않았으므로 온도 및 기간에 안정함을 확인할 수 있었고, 식품 보존제로서의 가능성 확인 시험에서도 기존의 식품 보존제보다 안전성이 있는 항균활성 물질로 평가되었다.

• Journal of Microbiology and Biotechnology
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• 제31권1호
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• pp.115-122
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• 2021

Phenol-soluble modulins (PSMs) are responsible for regulating biofilm formation, persister cell formation, pmtR expression, host cell lysis, and anti-bacterial effects. To determine the effect of psm deletion on methicillin-resistant Staphylococcus aureus, we investigated psm deletion mutants including Δpsmα, Δpsmβ, and Δpsmαβ. These mutants exhibited increased β-lactam antibiotic resistance to ampicillin and oxacillin that was shown to be caused by increased N-acetylmannosamine kinase (nanK) mRNA expression, which regulates persister cell formation, leading to changes in the pattern of phospholipid fatty acids resulting in increased anteiso-C15:0, and increased membrane hydrophobicity with the deletion of PSMs. When synthetic PSMs were applied to Δpsmα and Δpsmβ mutants, treatment of Δpsmα with PSMα1-4 and Δpsmβ with PSMβ1-2 restored the sensitivity to oxacillin and slightly reduced the biofilm formation. Addition of a single fragment showed that α1, α2, α3, and β2 had an inhibiting effect on biofilms in Δpsmα; however, β1 showed an enhancing effect on biofilms in Δpsmβ. This study demonstrates a possible reason for the increased antibiotic resistance in psm mutants and the effect of PSMs on biofilm formation.