• 한국식품영양학회지
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• 제12권2호
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• pp.199-203
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• 1999

To evaluate antidental caries activity of polylysine cell growth and acid production of Streptococcus mutans and lactobacillus acidophilus were microbiologically monitored in anaerobic broth system containing various concentration of polylysine. The pH and heat stability of polylysine having antimicrobial activity were also examined. Two tested microbes were fairly well grown in broth containing polylysine 0.1mg/ml however inhibited at 1 and 2mg/ml of polylysine concentration. Especially lag times of Strep-tococcus mutans and Lactobacillus acidophilus were prolonged to about hour at 1.0 and 2.0 mg/ml of poly-lysine. acid production of Streptococcus mutans and lactobacillus acidophilus was also decreased by poly-lysine. Antimicrobial activity of polylysine was not affected by the change of pH and the heat treat-ment.

• Journal of Microbiology and Biotechnology
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• 제23권7호
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• pp.1015-1022
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• 2013

We recently showed that polylysine, the polymer of lysines, retains anti-prion activity. Although the effectiveness of prion inhibition by polylysine was demonstrated with the regimen tolerated in mice, a determination of quantitative polylysine toxicity is necessary to precisely address the in vivo toxicity level of polylysine. In this communication, we report the results of body weight monitoring and hematologic tests performed in CD-1 mice that received two different tolerable dosages of polylysine for an either 5-day or 4-week period. We found that there was no significant alteration in overall serum chemistry, blood cell count, and body weight gain compared with controls. The only notable quantitative change with statistical significance was the decrease of platelet numbers in mice subchronically administered with polylysine. Our results suggest that polylysine is harmless in mice if administered for a short period, but administrations of polylysine in mice may require considerate attention for safety in future investigations as mice chronically receive tolerable doses of polylysine.

• 한국식품영양과학회지
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• 제33권4호
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• pp.705-710
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• 2004

$\varepsilon$-Polylysine에 grapefruit seed extract와 glyceride를 각각 혼합한 항균보존제의 식품부패균에 대한 항균효과를 MIC test와 실제 쌀밥에 적용하였다. 두 혼합 항균제 모두 clear zone을 나타내었으나, $\varepsilon$-polylysine과 grapefruit seed extract 혼합물이 $\varepsilon$-polylysine과 monoglyceride 혼합물보다 약 100배정도 낮은 minimum inhibitory concentration을 보였다. Glyceride 첨가제의 실험에서 Bacilius cereus와 Pseudomonas aerugines의 경우 0.1 $\mu$L/mL에서 생육이 저해된 것에 반해 Escherishia coli의 경우 15 $\mu$L/mL에 저해되어 E. coli가 이 항균제에 대하여 강한 저항성을 보이는 것으로 나타났다. 취반 시 glyceride 흔합항균제를 여러 농도별 (0.3%, 0.5%, 1%)로 첨가시킨 쌀밥을 72시간동안 저장하였을 때 총균수는 항균제의 농도가 증가할수록 감소하는 경향을 보였다. 쌀밥에 E. coli를 접종하여 항균제 농도에 따른 생육억제효과를 측정한 결과 항균제 농도가 높을수록 강하게 생육을 억제하였다. 항균제가 쌀밥의 관능에 미치는 영향은 맛, 냄새, 입안에서의 조직감에서는 유의적인 차이를 보이지 않았으나, 전체적인 기호도에서 1% 첨가군이 유의적인 차이를 보여 0.5%의 첨가가 적합한 것으로 나타났다.

• 한국식품저장유통학회지
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• 제12권4호
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• pp.323-328
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• 2005

천연 항균성 peptide인 polylysine을 이용한 항균성 포장재의 개발을 위한 기초자료를 얻기 위하여 polyamide 수지를 기반으로 하는 제조조건을 검토하고 두부를 대상식품으로 하여 병원성 및 부패 관련 미생물에 대한 항균활성을 확인하였다. Polylysine 제조조건에 있어서는 polylysine, polyamide의 농도와 코팅필름의 두께에 따라 항균활성에 큰 차이를 보였으나, $1.0\%$ 이상의 polylysine, $40\%$ polyamide, $50\;{\mu}m$ 이상의 필름 두께로 제조한 필름에 상대적으로 가장 높은 항균활성을 나타내었다. Polylysine의 용출량은 코팅된 필름을 멸균수에서 7일간 침지시킨 결과 침지 3일 까지 최대 약 $20\;{\mu}g/mL$의 농도를 나타낸 후 평형에 도달하였다. 코팅 필름의 항균활성은 초기 생균수 $4.8{\times}10^5\;CFU/mL$인 B. cereus에 대해 대조구에 비해 침지 7일 후 최대 105 CFU/mL수준의 감균효과를, 그리고 초기 생균수 $6.8{\times}10^5\;CFU/mL$인 K. pneumoniae에 대해서는 대조구에 비해 침지 7일 후 최대 $10^2\;CFU/mL$ 수준의 감균효과를 나타내어 polylysine 코팅 필름의 항균성 포장재로서의 활용 가능성을 확인 할 수 있었으며 polylysine 코팅 필름을 상업적으로 적용하기 위해서는 저농도의 두꺼운 필름보다는 고농도의 얇은 필름이 미생물의 증식을 저해하는데 효과적이라고 판단된다. 또한 필름으로부터 polylysine 용출을 용이하도록 하기 위한 연구가 추가로 연구되어야 하겠다.

• Geomechanics and Engineering
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• 제12권5호
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• pp.753-770
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• 2017

The coagulation or flocculation of cohesive clay suspensions is one of the most widely used treatment technologies for contaminated water. Flocculated clay can transport pollutants and nutrients in ground water. Coagulants are used to accelerate these mechanisms. However, existing coagulants (e.g., polyacrylamide, polyaluminum chloride) are known to have harmful effects in the environment and on human health. As an alternative, eco-friendly coagulant, this study suggests ${\varepsilon}-polylysine$, a cationic biopolymer fermented by Streptomyces. A series of sedimentation experiments for various ${\varepsilon}-polylysine$ concentrations were performed, and the efficiency of sedimentation with ${\varepsilon}-polylysine$ was estimated by microscopic observation and light absorbance measurements. Two types of sedimentation were observed in the experiments: accumulation sedimentation (at 0.15%, 0.20%, 0.25% ${\varepsilon}-polylysine$) and flocculation sedimentation (at 0%, 0.1%, 0.5%, 1.0%, 2.0% ${\varepsilon}-polylysine$). These sedimentation types occur as a result of the concentration of counter ions. Additionally, the performance of ${\varepsilon}-polylysine$ was compared with that of a previously used environmentally friendly coagulant, chitosan. The obtained results indicate that flocculation sedimentation is appropriate for contamination removal and that ${\varepsilon}-polylysine$ functions more efficiently for clay removal than chitosan. From the experiments and analysis, this paper finds that polylysine is an alternative eco-friendly coagulant for removing chemical contaminants in groundwater.

• Journal of Microbiology and Biotechnology
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• 제26권9호
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• pp.1657-1660
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• 2016

Prion diseases are incurable neurodegenerative disorders. Our previous study demonstrated that polylysine was effective in prolonging the incubation period in a rodent model and in alleviating the scrapie prion protein (PrP^Sc) burden in the brain at the terminal stage of the disease. Here, we report that intraperitoneal administration of polylysine suppresses the accumulation of prions in the spleen during the early stages of the disease. This study supports the congruence of PrP^Sc inhibition by polylysine in both the spleen and brain.

• 한국식품저장유통학회지
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• 제10권3호
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• pp.278-283
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• 2003

김치 제조시 위생적 품질 개선을 위하여 ethanol과 천연항균물질인 polylysine의 복합 첨가를 검토하였다. Ethanol 농도를 0.3, 0.6 및 0.9%로 첨가하여 김치를 제조한 후 1$0^{\circ}C$에 저장하면서 3일 간격으로 총균수, 대장균군, 젖산균, 곰팡이 및 효모 등을 비교 측정한 결과, ethanol의 첨가는 대장균군과 젖산균의 생육 억제에 있어 보다 효과적인 것으로 나타났으며, ethanol 농도 0.6% 첨가시부터 미생물 생육 억제 효과가 뚜렷하게 나타났다. 또한 ethanol 0.6%를 첨가하여 담근 김치는 저장중 pH 저하 및 산도 상승에 대한 지연효과를 보여주었고, 저장중 관능특성의 변화에서도 신냄새, 이취, 신맛, 이미, 조직감 및 종합적 기호도의 모든 항목에서 가장 우수한 것으로 평가되었다. Polylysine은 단일 사용시보다는 0.6% ethanol과 복합 첨가했을 경우 미생물 생육 억제에 상승효과를 보였으나 관능평가에서 이미 및 이취를 느끼는 것으로 평가되어 0.6% ethanol 단일 첨가가 미생물 증식 억제 및 발효 지연에 가장 효과적인 것으로 나타났다.

• Geomechanics and Engineering
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• 제17권5호
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• pp.453-464
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• 2019

Soft marine soil has high fine-grained soil content and in-situ water content. Thus, it has low shear strength and bearing capacity and is susceptible to a large settlement, which leads to difficulties with coastal infrastructure construction. Therefore, strength improvement and settlement control are essential considerations for construction on soft marine soil deposits. Biopolymers show their potential for improving soil stability, which can reduce the environmental drawbacks of conventional soil treatment. This study used two biopolymers, an anionic xanthan gum biopolymer and a cationic ${\varepsilon}-polylysine$ biopolymer, as representatives to enhance the geotechnical engineering properties of soft marine soil. Effects of the biopolymers on marine soil were analyzed through a series of experiments considering the Atterberg limits, shear strength at a constant water content, compressive strength in a dry condition, laboratory consolidation, and sedimentation. Xanthan gum treatment affects the Atterberg limits, shear strength, and compressive strength by interparticle bonding and the formation of a viscous hydrogel. However, xanthan gum delays the consolidation procedure and increases the compressibility of soils. While ${\varepsilon}-polylysine$ treatment does not affect compressive strength, it shows potential for coagulating soil particles in a suspension state. ${\varepsilon}-Polylysine$ forms bridges between soil particles, showing an increase in settling velocity and final sediment density. The results of this study show various potential applications of biopolymers. Xanthan gum biopolymer was identified as a soil strengthening material, while ${\varepsilon}-polylysine$ biopolymer can be applied as a soil-coagulating material.

• BMB Reports
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• 제30권5호
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• pp.308-314
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• 1997

We investigated biotinylation of nitrocellulose membrane for immuno-filtration capture assay. In order to enhance the efficiency of biotinylation, nitrocellulose membranes were pretreated with several chemicals for the purpose of suitable protein absorption through surface modification. As a signal generating enzyme, urease was used and the concentration of avidin was optimized for the efficient binding kinetics between urease-biotin in liquid phase and biotinylated membrane in solid phase. For effective biotinylation, bovine serum albumin-biotin complexes could be immobilized at a concentration of $370\;{\mu}g$/stick ($4.4\;cm^2$). Among tested chemicals, polylysine (0.25%) showed a significant effect in biotinylation. Polylysine is thought to enhance surface area by extending unbound residues into solution. Time of treatment over 30 min and higher molecular weight of polylysines (58,100 dalton) showed positive effect on the enhancement of biotinylation. The result from this study may be useful for developing a new biosensor and other biofunctional membranes for examining molecular recognition.

• 대한화장품학회지
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• 제47권2호
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• pp.155-161
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• 2021

본 연구는 항균 활성을 갖는 천연 소재를 검색하고 화장품의 보존제로써 적용을 위해 진행되었다. 디스크 확산법(disc diffusion method)을 통해 피부 병원성균 3 종(Staphylococcus aureus, Escherichia coli (E. coli), Pseudomonas aeruginosa)과 효모균(Candida albicans (C. albicans))에서의 천연 항균 소재 9 종을 검색하였다. Inhibition zone 크기를 측정한 결과, 오배자 추출물(Rhus Semialata gall (Gallnut) extract), 참나무 목초액 (Oak vinegar) 그리고 폴리리신(ε-polylysine)은 10 mm 이상으로 다른 추출물에 비해 우수한 항균활성을 나타내었다. 병원성균 3종과 효모균, 곰팡이균(Aspergillus brasiliensis (A. brasiliensis))에서 최소살균농도(minimum bactericidal concentration, MBC)를 측정한 결과, 오배자 추출물과 참나무 목초액은 5 종의 병원성균에서 10 ~ 20 mg/mL와 20 ~ 40 mg/mL, 폴리리신의 경우 진균류에서 0.5 ~ 2 mg/mL으로 살균 작용에 의한 항균효과를 각각 확인하였다. Checkerboard 방법에 따라 오배자 추출물과 참나무 목초액, 오배자 추출물과 폴리리신의 혼합 비율에 따른 시너지 효과(synergistic effect), 부가 효과(additive effect), 무관함(indifferent) 그리고 상쇄효과(antagonistic effect)를 평가하였다. 그 결과, 단독으로 사용할 때보다 오배자 추출물과 참나무 목초액 복합물은 E. coli, C. albicans, A. brasiliensis를, 오배자 추출물과 폴리리신 복합물은 C. albicans, A. brasiliensis를 4 배 낮은 농도에서 99.9% 억제하며 항균 시너지 효과를 확인하였다. 오배자 추출물과 참나무 목초액 복합물은 S. aureus와 P. aeruginosa를 2 배 낮은 농도에서 억제하며 부가 효과가 확인되었다. 이로써, 오배자 천연 복합물은 항균 시너지 효과를 발휘할 수 있음을 입증했을 뿐만 아니라 넓은 항균 스펙트럼을 갖춘 천연 방부 시스템으로써 화장품에서 응용할 수 있을 것으로 기대된다.