• Applied Biological Chemistry
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• 제50권4호
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• pp.262-267
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• 2007

토양에는 생존하지만 현 기술로는 배양이 불가능한 미생물로부터 천연 항생제를 탐색하기 위해 한국 토양 DNA 단편들을 가진 cosmid library을 대장균에서 제작하였고 약6만개의 clone들을 대상으로 항세균 활성을 보여주는 YS92B를 최종 선발하였다. YS92B클론 배양액의 ethyl acetate추출액은 다양한 병원성 세균의 성장을 in vitro에서 강력히 저해하였다(Listeria monocytogenes, Bacillus subtilis, Pseudomonas syringae, Xanthomonas campestris pv. oryzae, Staphylococcus epidemis). 이 항균활성의 주 물질인 YS92B-VII는 ethyl acetate추출, Sephadex LH20 column chromatography와 HPLC(High Performance Liquid Chromatography)에 의해 순차적으로 분리하였으며 이 과정에서 주 활성물질은 각 피크를 항균검정으로 추적하여 최종 정제하였다. 이 물질은 NMR(Nuclear Magnetic Resornance)에 의한 구조 분석 결과에서 탄소 12개의 포화지방산인 lauric acid가 tyrosine에 결합된 N-lauroyl tyrosine임을 최종 확인하였다. 따라서 본 보고는 한국 토양에서 유래한 고유의 N-acyl amino acid synthase(NAS)유전자가 대장균에 발현되어 생산되는 N-acyl amino acid tyrosine의 특성을 밝히는 것이다.

• Advances in nano research
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• 제17권1호
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• pp.51-59
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• 2024

Nanotechnology, the science of manipulating matter at the nanoscale, offers remarkable opportunities for innovation across various fields. Nanomaterials, which form the cornerstone of advanced materials, drive forward new ideas and groundbreaking applications. In the textile industry, traditional antibacterial and antifungal garments are typically treated with chemical compounds to inhibit bacterial growth. However, these treatments often lack durability, losing effectiveness after multiple washes. To address this limitation, the application of green nanotechnology in developing high-performance textiles emerges as a promising solution. This study explores the integration of nanocomposites into the polymer layers of footballs to enhance their stability and performance. By embedding nanoparticles within the polymer matrix, the durability and resilience of the footballs are significantly improved, leading to better control and performance on the field. This innovative approach not only extends the lifespan of the footballs but also provides economic advantages by reducing the frequency of replacements. Additionally, the enhanced stability contributes to a more consistent and reliable playing experience, promoting improved safety and performance for athletes.

• 한국미생물·생명공학회지
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• 제38권1호
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• pp.105-111
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• 2010

소목은 전통적으로 타박상, 염증 등의 질병치료를 위해 민간의학에서 오래 동안 사용되어 온 한약재야다. 소목의 섬재로부터 항균효과를 조사하기 위하여 MeOH 추출에 의한 hexane, $CHCl_3$, EtOAc, n-BuOH, MeOH 및 $H_2O$ 분획을 얻었다. 분획 시료 중 3.94%의 가장 높은 수율의 EtOAc 분획이 조사된 인채 병원성 세균에 대해 가장 강한 항균활성 나타냈다. 또한 EtOAc 분획의 항균활성은 Gram (-) 균주 보다 Gram (+) 균주에 더 효과적이며, Gram (-) 균주에 대해서는 세균에 따른 항균활성의 차이를 보였다. EtOAc 분획은 silica gel adsorption column chromatography 및 Sephadex LH-20을 이용하여 분리하였으며 수득한 주요 성분은 채결정을 통하여 얻어진 단일물질을 HPLC를 이용하여 순도를 측정하였다. 300g의 C. sappan으로부터 3.94%의 EtOAc 분획을 얻었으며 EtOAc분획물은 분석한 결과 10 mg에는 1.67 mg의 brazilin을 포함하였다. 분리된 활성울질은 짧은 황색 결정의 단일 화합물로 MS에 의해 분자량이 285로 나타났으며, $^1H$-NMR, $^{13}C$-NMR에 의한 구조분석으로 brazilin($C_{16}H_{14}O_5$을 동정하였다. 이 같은 결과는 소목의 MeOH 추출에 의한 EtOAc 분획에 존재하는 brazilin이 S. aureus와 같은 인체 병원성 Gram (+) 균주에 대한 생약치료제로 활용이 가능할 것을 시사한다.

• 청정기술
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• 제28권1호
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• pp.24-31
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• 2022

오늘날 다양한 용도로 사용하고 있는 석유계 플라스틱은 지구 환경 및 생태계에 큰 위협을 주는 존재로서 이를 대체하기 위한 방안을 찾기 위해 범세계적으로 각 분야에서 많은 노력이 가해지고 있다. 이런 관점에서 본 연구에서는 생분해성 특성을 지닌 해양 바이오매스 유래 알지네이트에 석유계 기반의 폴리비닐알콜(Poly vinyl alcohol; PVA)을 10 wt% 혼합하여 알지네이트 기반 폴리비닐알콜 블렌드 필름(alginate-based PVA blend films)을 수용액상으로부터 캐스팅하여 제조하였다. 가교제로는 글루타르알데히드가 사용되었으며, 필름에 항균성을 부여하고자 캐슈넛껍질액으로부터 추출된 알킬 페놀계 바이오오일인 카다놀(cardanol) 성분을 0.1 ~ 2.0 wt% 범위로 첨가하였다. 이렇게 제조된 블렌드 필름의 특성을 알아보기 위하여 푸리에변환 적외선 분광법(FTIR), 열중량분석(TGA), 인장강도, 팽윤도 및 항균성 등을 측정하였다. FTIR과 열중량분석, 인장강도 결과들은 주성분인 알지네이트에 PVA가 하나의 매트릭스 상을 이루며 잘 분산되어 있음을 보여주었고, 특히, 단일 성분일 때 약점으로 알려진 알지네이트의 취성(brittle)과 PVA의 약한 열적 내구성이 블렌드를 이루면서 PVA와 알지네이트 기능기들의 가교 및 수소결합으로 인하여 열적, 기계적인 물성들이 향상됨을 보였다. 카다놀 성분의 첨가는 황색포도상구균과 대장균에 대한 항균성을 크게 향상시켜 60 min 접촉시간에서 황색포도상구균의 사멸율은 98% 이상이고, 대장균의 경우 약 70%의 우수한 향균 성능을 나타냈다. 알지네이트-PVA 블렌드에 대한 최적 항균성은 카다놀이 0.1 ~ 0.5 wt% 범위이었다. 이상의 결과들을 볼 때, 카다놀을 함유한 알지네이트-PVA 블렌드 필름은 식품 포장제 및 여러 항균소재로서 응용할 수 있을 것으로 판단된다.

• 한국결정성장학회지
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• 제15권6호
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• pp.263-268
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• 2005

[ $20{\sim}40nm$ ] 크기의 Ag 콜로이드가 첨가된 세라믹 볼을 이용하여 음용수중의 중금속 흡착 및 항균성에 대한 특성을 평가하였다. 다공성이 우수한 세라믹 볼을 제조하기 위한 조건은 다음과 같다. 즉, 출발원료: 85wt%의 $Ca_{10}(PO_4)_6(OH)_2$, 바인더: 5wt%의 PVA 및 15wt%의 $\alpha-Ca_3(PO_4)_2$, 열처리온도: $1000^{\circ}C$, 반응시간: 3시간 이었다. 이와 같은 조건에서 얻어진 세라믹 볼은 비표면적이 $110m^2/g$ 이었으며, $120{\mu}m$의 기공크기와 80%의 기공율을 나타내었다. 그리고 AAS를 이용하여 음용수중의 중금속 흡착 제거율에 대한 성능시험을 행한 결과, Zn, Mn, Cu, Fe와 같은 중금속이 담지 1일 후 0.03mg/l 이하로 제거 되었으며, 침적시간 3시간 후에는 대장균이 모두 멸균되는 우수한 살균력을 나타내었다.

• 대한수의학회지
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• 제37권2호
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• pp.321-330
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• 1997

Enrofloxacin is one of the second-generation quinolones which have been widely used to treat bacterial infections in various species including chicken, pig, horse and cattle. The objective of the present study was to describe the serum bactericidal activity(SBA) of enrofloxacin, its pharmacokinetic behaviors after intramuscular or intravenous administration to Korean native goats in the dose rate of 5mg/kg b.w. The results obtained through this study were as follows : 1. Sera collected from both sexes of Korean native goats administered 5mg/kg i.v. or i.m. showed potent antibacterial activities up to the 12 hours by way of the serum bactericidal activity. 2. Concentrations of enrofloxacin in the biological samples were measured by high-performance liquid chromatography(HPLC) so as to study pharmacokinetic characteristics. For detection of enrofloxacin, 10% TCA was optimal for protein precipitation and the mobile phase was 0.01M citric acid/methanol/acetonitrile(7/2/1, pH 3.5) with solid phase being the $C_{18}$ reversephase column and detection wavelength being 278nm. The limit of detection of enrofloxacin on HPLC was $0.05{\mu}g/ml$. 3. Pharmacokinetic profile of enrofloxacin administered 5mg/kg i.v. in Korean native goats was best described by two-compartment open model and that administered i.m. the same rate by one-compartment model. There were no sex differences in pharmacokineticl parameters. In conclusion, enrofloxacin showed potent in vivo antibacterial activity and excellent pharmacokinetic properties in Korean native goats, hence it may be used as a potential antibacterial in the veterinary clinical settings.

• Journal of Veterinary Science
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• 제24권6호
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• pp.74.1-74.15
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• 2023

Background: Antibiotic beads are used to treat local bacterial infections by delivering high drug concentrations to infected tissue. Objectives: This study examined the elution characteristics of metronidazole from metronidazole-calcium sulfate (MCa) and metronidazole-calcium-potassium sulfate (MCaK) beads over 20 days and the antibacterial efficacy of the beads after storage. Methods: The MCa and MCaK beads were prepared by mixing 250 mg of metronidazole and 10 g of calcium sulfate hemihydrate with water and a 3% potassium sulfate solution, respectively. The beads were placed in phosphate-buffered saline for the elution study. The metronidazole eluents were determined using high-performance liquid chromatography. The microstructures were examined by scanning electron microscopy (SEM), and the antimicrobial activity was evaluated by a microbioassay. Results: For the 20-day study, the total amount of metronidazole released was greater in the MCa beads than in the MCaK beads by 6.61 ± 0.48 mg (89.11% ± 3.04%) and 4.65 ± 0.36 mg (73.11% ± 4.38%), respectively. The amounts of eluted drugs from the MCa and MCaK beads were higher than the minimum inhibitory concentration at 0.5 ㎍/mL against anaerobic bacteria at both 20 days and 14 days. SEM showed that calcium crystals on the outer surface had dissolved after elution, and thinner calcium crystals were prominent in the MCaK beads. The MCa and MCaK beads exhibited antibacterial activity after setting, followed by storage at room temperature or 4℃ for 21 days. Conclusions: The MCa beads could release more drug than the MCaK beads, but all eluted metronidazole amounts were effective in controlling bacterial infections. Both metronidazole beads could be stored at ambient temperature or in a refrigerator.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.179-179
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• 2005

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1579-1585
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• 2016

Sugar esters are valuable compounds composed of various sugars and fatty acids that can be used as antibacterial agents and emulsifiers in toothpaste and canned foods. For example, fructose fatty acid esters suppress growth of Streptococcus mutans, a typical pathogenic bacterium causing dental caries. In this study, fructose laurate ester was chosen as a target material and was synthesized by a transesterification reaction using Candida antarctica lipase B. We performed a solvent screening experiment and found that a t-butanol/dimethyl sulfoxide mixture was the best solvent to dissolve fructose and methyl laurate. Fructose laurate was synthesized by transesterification of fructose (100 mM) with methyl laurate (30 mM) in t-butanol containing 20% dimethyl sulfoxide. The conversion yield was about 90%, which was calculated based on the quantity of methyl laurate using high-performance liquid chromatography. Fructose monolaurate (M_r 361) was detected in the reaction mixture by high-resolution mass spectrometry. The inhibitory effect of fructose laurate on growth of oral or food spoilage microorganisms, including S. mutans, Bacillus coagulans, and Geobacillus stearothermophilus, was evaluated.

• Mycobiology
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• 제44권4호
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• pp.338-342
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• 2016

The culture filtrate of Lentinula edodes shows potent antimicrobial activity against the plant pathogenic bacteria Ralstonia solanacearum. Bioassay-guided fractionation was conducted using Diaion HP-20 column chromatography, and the insoluble active compound was not adsorbed on the resin. Further fractionation by high-performance liquid chromatography (HPLC) suggested that the active compounds were organic acids. Nine organic acids were detected in the culture filtrate of L. edodes; oxalic acid was the major component and exhibited antibacterial activity against nine different phytopathogenic bacteria. Quantitative analysis by HPLC revealed that the content of oxalic acid was higher in the water extract from spent mushroom substrate than in liquid culture. This suggests that the water extract of spent L. edodes substrate is an eco-friendly control agent for plant diseases.