• 약학회지
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• 제42권3호
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• pp.248-256
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• 1998

We had already reported that we purified N-${\beta}$-alanyl-5-S-glutathionyl-3,4-dihydroxyphenylalanine (5-S-GAD), a novel antibacterial substance from the immunized adult Sarcoph aga peregrina (Flesh fly). We found that the antibacterial activity of synthetic 5-S-GAD is equal to that of authentic 5-S-GAD without a specificity of antibacterial activity against Gram positive and Gram negative. Significant synergism was detected between 5-S-GAD and streptomycin against streptomycin resistant strain E.coli K12 594. It has an antitumor activity against several tumor cell lines at a concentration of $100{\mu}M$. However, no cytotoxic activity against murine macrophage was detected at a concentration of $500{\mu}M$. Furthermore, haemolytic activity against sheep erythrocytes was not detected at the same concentration. We suggest that the S-conjugation of glutathion with dihydroxyphenylalanine might be important to increase antibacterial activity of dihydroxyphenylalanme.

• 한국약용작물학회지
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• 제20권5호
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• pp.308-314
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• 2012

This study was carried out to investigate the antibacterial activity against pathogens of acne and the anti-inflammatory effect of 75% ethanol extract and its fractions from the leaves of Prunus sargentii. In the antibacterial activity by the disc diffusion assay, the extract showed the highest effect against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis in 5 mg/disc. However, the ethyl acetate fraction showed the highest antibacterial activity in 1 mg/disc. On the other hand, the hexane and chloroform fraction showed strong nitric oxide (NO) production inhibitory effect in lipopolysaccharide (LPS)-stimulated Raw 264.7 cell. In the cell viability of Raw 264.7 by MTT assay, the extract and all fractions were exhibited normal viabilities as nontoxic result. Consequently, the extract from the leaves of P. sargentii and its ethyl acetate fraction could be applicable to functional materials for antibacterial activity related fields. Moreover, the hexane and chloroform fraction could be applicable to candidate materials as anti-inflammatory agent.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.93-100
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• 2020

A bacterial strain inhibiting the growth of Vibrio anguillarum, the causative agent of vibriosis, was isolated from fish intestines. The isolated strain HS36 was identified as Aerococcus urinaeequi based on the characteristics of the genus according to Bergey's Manual of Systematic Bacteriology and by 16S rRNA sequencing. The growth rate and antibacterial activity of strain HS36 in shaking culture were higher than those in static culture, while the optimal pH and temperature for antibacterial activity were 7.0 and 30℃, respectively. The active antibacterial substance was purified from a culture broth of A. urinaeequi HS36 by Sephadex G-75 gel chromatography, Sephadex G-25 gel chromatography, and reverse-phase high-performance liquid chromatography. Its molecular weight, as estimated by Tricine SDS-polyacrylamide gel electrophoresis, was approximately 1,000 Da. The antibacterial substance produced by strain HS36 was stable after incubation for 1 h at 100℃. Although its antibacterial activity was optimal at pH 6-8, activity was retained at a pH range from 2 to 11. The purified antibacterial substance was inactivated by proteinase K, papain, and β-amylase treatment. The newly purified antibacterial substance, classified as a class II bacteriocin, inhibited the growth of Klebsiella pneumoniae, Salmonella enterica, and Vibrio alginolyticus.

• 한국치위생학회지
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• 제23권6호
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• pp.459-466
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• 2023

Objectives: The purpose of this study was to evaluate the physical properties and antibacterial activity of denture base resin with added silver sulfadiazine. Methods: Specimens were made from self-curing denture base resin and silver sulfadiazine as an inorganic antibacterial agent. For physical evaluation of the specimens, surface roughness, surface hardness, and contact angle were measured. Bacterial growth was assessed by optical densityat 600 nm (OD600) and colony forming units (CFU) measurements to confirm antibacterial activity. Results: There was no significant difference in surface roughness, surface hardness, and contact angle in the experimental group containing silver sulfadiazine compared to the control group. In contrast, the experimental group showed a significant decrease in antibacterial activity compared to the control group in terms of OD value. Analysis of CFU confirmed a significant decrease in colonies in the experimental group compared to the control group. Conclusions: Denture base resin containing silver sulfadiazine, an inorganic antibacterial agent, exhibited enhanced antibacterial activity without physical changes. In conclusion, the use of denture base resin containing inorganic antibacterial agents may be expected in the future.

• Biomolecules & Therapeutics
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• 제1권2호
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• pp.196-203
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• 1993

We compared in vitro antibacterial activity of DWC-751, a new parenteral cephalosporin antibiotic, with those of cefpirome (CPR), cefotaxime (CTX) and ceftazidime (CAZ). DWC-751 showed a broad antimicrobial spectrum against Gram-positive and negative bacteria. The antibacterial activity of DWC-751 against Stapylococcus aureus was equal to that of CPR and superior to those of CTX and CAZ. The activity of it against Excherichia coli was more potent than those of CPR, CTX and CAZ. Against Pseudomonas aeruginosa, DWC-751 was slightly inferior to that of CAZ and superior to those of CPR and CTX. The antibacterial activity of DWC-751 was superior to those of CPR, CTX and CAZ against clinical isolates and ofloxacin resistant strains. DWC-751 showed bactericidal action against Escherichia coli at concentrations close to the MIC and induced the formation of filament and burge and lysis of Escherichia coli in a microscopic examination.

• 대한의생명과학회지
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• 제15권1호
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• pp.73-80
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• 2009

Bloodstream infections (BSI) are caused by planktonic microorganisms, sometimes leading to serious infections such as bacteremia and sepsis. BSI occurs more frequently to the patients wearing the central venous catheter (CVC). The ciprofloxacin-incorporated CVC (CFX-CVC) has been reported previously to possess antimicrobial activity. In this study, the antibacterial activity of CFX-CVC and its mechanism against planktonic BSI cells were explored by using the shake flask test and by examining the release rate of 260 nm-absorbing substances from the bacterial cells indicative of the membrane damage of the bacterial cells. CFX-CVC reduced more than 99.9% of the viable planktonic BSI cells demonstrating its potent antibacterial activity. It provoked bacteriolysis causing leakage of a large amount of 260 nm-absorbing materials from the planktonic bacterial cells like S. aureus and E. coli. These results provide evidence that the antibacterial activity of CFX-CVC came from the inhibition of the stability of the planktonic bacterial cells.

• Preventive Nutrition and Food Science
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• 제3권4호
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• pp.320-323
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• 1998

Lysozyme was covalentyl conjugated with galactomannan through a amino-carbonyl reaction between the lysine $\varepsilon$-amino groups of lysozyme and the reducing ends of galactomannan at a relative humidity of 79% and 6$0^{\circ}C$. The resulting lysozyme-galactomannan conjugate (LGC) was investigated for its antibacterial activity against Escherichia coli. Lysozyme alone did not exhibit antibacterial activity against E. coli. in contrast , significant bactericidal effect was observed for LGC, depending on the reaction temperature. The degree of conjugation between lysozyme and galactomannan was dependent on the incubation time, which affected the antibacterial efficiency against E. coli. This study demonstrated that the amino-carbonyl reaction between lysozyme and galactomannan could be a potential tool to modify lysozyme toward broadening its antibacterial spectrum to Gram-negative bacteria.

• 한국유기농업학회지
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• 제24권3호
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• pp.497-510
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• 2016

본 연구는 Lactobacillus bulgaricus SP5 분비물의 항균물질 탐색과 특성을 조사하고 병원성 미생물에 대한 억제효과를 얻고자 실시하였다. L. bulgaricus로부터 얻어진 상징액에 대한 항균활성은 시험에 이용된 모든 병원성 미생물인 E. coli 11234, Salmonella. enteritidis 3313, S. enteritidis 12021, 그리고 S. typhimurium 40253에 대해서 항균활성을 가지는 것으로 나타났다. 상징액 중의 황균활성 성분을 확인하기 위하여 다양한 pH 조정과 열처리 후, 병원성 미생물에 대한 항균활성을 측정하였다. 상징액의 열처리 후, 병원성미생물에 대한 항균활성은 비열처리와 같은 항균활성을 나타내었으나, 상징액의 pH를 4.6에서 중성이상으로의 변화는 항균활성이 현저히 감소하였다. 따라서 상징액의 항균활성은 pH 변화에 대해서 불안정하였으나, 열에 대해서는 매우 안정한 것으로 밝혀졌다. 이상의 결과를 통해 상징액의 병원성균에 대한 항균작용은 박테리오신 같은 peptide 보다는 lactic, acetic, phosphoric, succinic, pyroglutamic, citric, malic, 그리고 formic acid 등 다양한 유기산의 작용에 의한 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제11권4호
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• pp.720-723
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• 2001

The effect of long-term storage on garlic antibacterial activity was investigated. A concentration of 5% or more garlic was found to be necessary to completely inhibit Eschrichia coli growth in tryptic soy broth. This value is substantially higher than the minimum inhibitory concentration of 1% for E. coli reported previously. pH-modified garlic extract was stored at different temperatures to investigate the impact of storage conditions (i.e., temperature, pH, period of storage) on the stability of the antibacterial activity of the garlic extract used against E. coli B34. The antibacterial effectiveness of the garlic extract against E. coli remained stable when both the storage temperature and the pH of the extract were kept low. When the garlic extract was stored at $40^{\circ}C and above, most or all of the garlic antibacterial activity disappeared after a 24-h storage period, regardless of the storage pH. The antibacterial activity was weakened when the pH of the garlic extract was adjusted to 8, and at low temperatures.

• 한국의류산업학회지
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• 제8권6호
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• pp.702-708
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• 2006

The purpose of this study was to investigate the dyeing-property and antibacterial activity on nylon fabric dyed with cochineal at variable dyeing conditions. Al, Cr, Fe, Cu and Sn were used as mordants and adsorption was compared with different mordanting methods. The maximum UV-visible absorption band of cochineal extract was 495 nm. The dyeability on nylon fabric was good because of having a amine group. The optimum dyeing conditions of nylon fabrics are dyeing concentration 1.5%(o.w.s), dyeing temperature $60^{\circ}C$, pH 3 and dyeing time 30 minutes. The pre-mordanting method is preferred for Al and Cr, and the post-mordanting one is preferred for Cu, Sn and Fe to achieve better dyeing. The optimum mordanting conditions of wool fabrics dyed with cochineal are mordanting concentration of 0.5%(o.w.s), mordanting temperature $60^{\circ}C$, and dyeing time 30 minutes. Nylon fabrics dyed with cochineal show a little antibacterial activity, but it was increased by Sn mordanting. MIC test results in antibacterial activities revealed that the antibacterial activity of Cu was the highest among mordants, but Sn mordant was the most effective in antibacterial activities after mordanting treatment of nylon fabric. The fastness properties of dyed nylon fabric showd a little worse or a similar level and there was no significant difference between a mordanted and non-mordanted fabric.