• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.2979-2984
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• 2014

Silver nanoparticles have been synthesized by liquid-phase and alcohol reduction methods. Silver-doped silica-complex nanoparticles were prepared using a sol-gel process. The formation, structure, morphology, and particle size of the nanoparticles have been studied using several techniques. Silver nanoparticles of size of 30-40 nm were formed successfully by alcohol reduction. TEM images show that both the concentration and the molecular weight of polyvinyl pyrrolidone (PVP) considerably affect the size of the emerging silver nanoparticles. The number of silver-doped silica-complex particles increased by a mercapto-group treatment that showed a narrower size distribution than that of silica treated with amino groups. The silver/polyester and silver-doped silica/polyester masterbatch chips showed excellent antibacterial activity against Staphylococcus aureus and Escherichia coli.

• 센서학회지
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• 제32권4호
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• pp.213-218
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• 2023

Triboelectric nanogenerators (TENGs) have emerged as a highly promising energy harvesting technology capable of harnessing mechanical energy from various environmental vibrations. Their versatility in material selection and efficient conversion of mechanical energy into electric energy make them particularly attractive. TENGs can serve as a valuable technology for self-powered sensor operation in preparation for the IoT era. Additionally, they demonstrate potential for diverse applications, including energy sources for implanted medical devices (IMDs), neural therapy, and wound healing. In this review, we summarize the potential use of this universally applicable triboelectric energy harvesting technology in the disinfection and blocking of pathogens. By integrating triboelectric energy harvesting technology into human clothing, masks, and other accessories, we propose the possibility of blocking pathogens, along with technologies for removing airborne or waterborne infectious agents. Through this, we suggest that triboelectric energy harvesting technology could be an efficient alternative to existing pathogen removal technologies in the future.

• 한국재료학회지
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• 제32권2호
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• pp.80-84
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• 2022

Copper nanoparticles (CuNPs) are considered of great importance due to their high catalytic and antimicrobial activities. This study focuses on the preparation and characterization of CuNPs, and on their antibacterial/antifungal activities. A copper salt (copper sulfate pentahydrate) as precursor, starch as stabilizing agent, and ascorbic acid as reducing agent were used to fabricate CuNPs. The resulting product was characterized via different techniques such as X-ray diffractrometry (XRD), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning electron microscopy (SEM) to confirm its characteristic properties. Employing the Scherrer formula, the mean crystallite sizes of copper (Cu) and cuprous oxide (Cu₂O) nanocrystals were found to be 29.21 and 25.33 nm, respectively, as measured from the main X-ray diffraction peaks. The functional groups present in the resulting CuNPs were confirmed by FTIR. In addition, the engineered CuNPs showed antibacterial and antifungal activity against tested pathogenic bacterial and fungal strains.

• 대한화장품학회지
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• 제46권2호
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• pp.159-166
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• 2020

프로폴리스는 식물에서 채취한 수지에 꿀벌의 분비물이 합쳐져 만들어진 아교성 물질로 세균이나 바이러스로부터 자신을 보호하는 기능을 한다. 본 연구에서는 한국, 중국, 브라질 유래 프로폴리스 추출물의 항산화, 항균, 미백, 항염 활성을 비교하고, 이들 추출물의 화장품소재로서의 응용가능성을 살펴보았다. 플라보노이드, 폴리페놀함량분석과 자유라디칼 소거능 시험을 통해 항산화 활성을 확인한 결과 한국, 중국, 브라질 프로폴리스 추출물 모두 유의한 항산화 효능을 보였다. 피부에 상재하는 미생물에 대한 항균효능을 MIC 시험법을 통해 측정한 결과 C. acnes 균에서 한국 프로폴리스 추출물이 다른 추출물에 비해 우수한 항균력을 보였다(KPE: 62.5 ㎍/mL, CPE: 250 ㎍/mL, BPE: 500 ㎍/mL). 또한, 한국 프로폴리스 추출물은 멜라닌 세포의 멜라닌 생성을 억제하였고, 마우스대식세포에서 리포폴리사카라이드로 유도된 염증인자인 산화질소와 PGE₂ 생성을 나머지 두 추출물보다 우수하게 억제하였다. 이들 결과를 종합하면 프로폴리스 추출물은 항산화, 항균, 항염 효능소재로 응용될 수 있으며, 특히 항균, 항염, 미백에서 우수한 효능을 보인 한국프로폴리스추출물의 응용가능성이 우수함을 확인할 수 있었다.

• 한국식품영양과학회지
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• 제40권3호
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• pp.466-469
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• 2011

본 연구는 복분자의 활용도를 높이기 위한 자료를 제공하고자 동결 건조한 완숙 복분자를 종자와 종자를 분리한 과육, 그리고 분리과정을 거치지 않은 과실로 구분하여 지방산조성 분석과 각 부위별 methanol 추출물의 여드름 관련 균주에 대한 항균 활성, 그리고 polyphenol 함량 및 DPPH radical 소거능을 비교 분석하였다. 지방산 조성 분석 결과 종자의 총 지방 및 지방산 함량이 다른 부위에 비해 월등히 높은 수준임을 알 수 있었다. 아울러 종자의 주요 지방산으로 밝혀진 linoleic acid와 linolenic acid의 함량이 전체 지방산 조성의 81.262%로 대부분을 차지하였다. Polyphenol 함량 측정에서 123.64 mg/g으로 가장 높은 수준의 polyphenol 함량을 보였던 종자의 methanol 추출물이 DPPH radical 소거능에서도 다른 추출물에 비해 높은 활성을 나타내었다. 여드름 원인균에 대한 항균 활성에서 실험에 사용된 모든 균주에 대해서 종자를 분리한 과육의 methanol 추출물이 상대적으로 가장 높은 항균 활성을 나타내었으며, 종자 추출물은 상대적으로 낮은 활성을 보여주었다. 그러나 가장 높은 활성을 나타낸 과육 추출물의 항균 활성과 비교해서 종자 추출물의 항균 활성이 각 균주별로 약 76.96~89.08%에 해당함을 알 수 있었다. 결과적으로 완숙 복분자의 과육 부분뿐만 아니라 잔사나 폐기물로 버려질 수 있는 종자 부위의 활용도를 높일 수 있는 가능성을 확인하였다.

• 멤브레인
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• 제33권6호
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• pp.398-408
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• 2023

본 연구는 지카바이러스, 메르스, coronavirus disease-19 (COVID-19) 등의 감염병 방역 및 의료현장에서 사용할 수 있는 의료용 공기정화호흡기(powered air purifying respirators, PAPR)의 항균성 보호복의 후드와 필터를 개발하였다. PAPR은 전동팬 본체 및 필터, 배터리팩, 후드로 구성되며 보호복의 후드 소재는 뛰어난 흡습성, 풍압, 외부충격을 견딜 수 있는 폴리프로필렌 슐폰레이스(spunlace) 부직포 직물(SFS)을 사용하였다. 사용자의 감염위험을 낮추기 위해 후드의 외피에는 피톤치드계 물질을 사용하여 99.9%의 안티-박테리얼(antibacterial) 효과를 얻었으며 내피에는 친수가공을 하여 흡수성을 25% 향상시켰다. 의료용 보호복 후드에 필요한 인공혈액 침투저항성, 건조미생물 침투저항성, 습식세균 침투저항성, 그리고 박테리오파아지 침투저항성을 평가한 결과 2~6 단계의 합격평가를 받았다. 한편, 항균 처리된 슐폰레이스(spunlace filter, SF) 헤파 필터(high efficiency particulate air, HEPA)의 성능을 평가한 결과 우수한 항균성, 분진제거율, 차압 효과를 확인하였다.

• 대한한방부인과학회지
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• 제25권3호
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• pp.27-39
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• 2012

Objectives: Recently Ciprofloxacin, used in the treatment of mastitis, showed many serious side effects. The object of this study was to recognize whether TNS and KWT can be used in the treatment of mastitis by observing the in vitro antibacterial effects of TNS and KWT aqueous herbal extracts against S. aureus. Methods: Antibacterial activities of TNS and KWT aqueous extracts against S. aureus ATCC 25923 were detected using standard agar microdilution methods. In addition, the effects on the bacterial growth curve were monitored at MIC and $MIC{\times}2$ levels. The effects on the intracellular killing and bacterial invasion of individual test materials were also observed using Raw 264.6 and MCF-7. The results were compared with Ciprofloxacin, a second generation of quinolone antibiotics in the present study. Results: MIC of aqueous extracts of TNS and KWT against S. aureus were detected as ($0.313{\pm}0.107$) and ($0.137{\pm}0.053$) mg/ml, respectively. MIC of Ciprofloxacin was detected as ($0.469{\pm}0.297$) ${\mu}g/ml$ at same conditions. In addition, TNS, KWT aqueous herbal extracts and Ciprofloxacin were also showed marked dosage-dependent inhibition of bacterial growth, and dramatical inhibitions on the both intracellular killing assays and bacterial invasion using Raw 264.6 and MCF-7 cells were detected. Conclusions: The results obtained in this study suggest that TNS and KWT aqueous herbal extracts showed antibacterial effects against S. aureus, and they also showed dosage-dependent inhibitory effects on the bacterial growth. And they showed the significant intracellular killing and bacterial invasion effects. It means, KWT and TNS may show more potent anti-infectious effects against S. aureus in vivo.

• Restorative Dentistry and Endodontics
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• 제38권1호
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• pp.36-42
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• 2013

Objectives: This study evaluated the antibacterial effect and mechanical properties of composite resins ($L_{CR}$, $M_{CR}$, $H_{CR}$) incorporating chitosan with three different molecular weights (L, Low; M, Medium; H, High). Materials and Methods: Streptococcus (S). mutans 100 mL and each chitosan powder were inoculated in sterilized 10 mL Brain-Heart Infusion (BHI) solution, and was centrifuged for 12 hr. Absorbance of the supernatent was measured at $OD_{660}$ to estimate the antibacterial activities of chitosan. After S. mutans was inoculated in the disc shaped chitosan-containing composite resins, the disc was cleansed with BHI and diluted with serial dilution method. S. mutans was spread on Mitis-salivarius bacitracin agar. After then, colony forming unit (CFU) was measured to verify the inhibitory effect on S. mutans biofilm. To ascertain the effect on the mechanical properties of composite resin, 3-point bending and Vickers hardness tests were done after 1 and 3 wk water storage, respectively. Using 2-way analysis of variance (ANOVA) and Scheffe test, statistical analysis was done with 95% significance level. Results: All chitosan powder showed inhibition effect against S. mutans. CFU number in chitosan-containing composite resins was smaller than that of control resin without chitosan. The chitosan containing composite resins did not show any significant difference in flexural strength and Vickers hardness in comparison with the control resin. However, the composite resin, $M_{CR}$ showed a slightly decreased flexural strength and the maximum load than those of control and the other composite resins $H_{CR}$ and $L_{CR}$. Conclusions: $L_{CR}$ and $H_{CR}$ would be recommended as a feasible antibacterial restorative due to its antibacterial nature and mechanical properties.

• 한국약용작물학회지
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• 제26권2호
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• pp.134-140
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• 2018

Background: The extract of Abies holophylla is used as an ingredient in cosmetics. This study assessed the antioxidant and antibacterial activities of the material remaining after the extract is used. Methods and Results: The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethyl benzothiazoline)-6-sulfonic acid (ABTS) radical scavenging abilities were assessed to determined the free radical scavenging activity. The total phenol and flavonoid contents were determined to measure the antioxidant activity. The DPPH and ABTS radical scavenging activities of the resudual extract were higher (95.61 - 99.42% and 74.26 - 77.98% in water extract respectively) than those of the positive control. In 50% EtOH extract, the total phenol content was $389.84mg{\cdot}GAE/m{\ell}$, and the total flavonoid was $0.15mg{\cdot}QE/m{\ell}$. The minimum inhibition concentration degree for antibacterial activity against Staphylococcus aureus was < 8 to < $125{\mu}g/m{\ell}$ compared to that of the positive control in all extracts. The clear zone against S. aureus was found to be $12.2{\pm}3.8mm$. Conclusions: The A. holophylla byproducts were found to have antioxidant and antibacterial activities. Therefore, the materials remaining after the A. holophylla extract is used in cosmetics has potential functional uses.

• 대한본초학회지
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• 제30권4호
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• pp.29-35
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• 2015

Objectives : The objective of this research was to investigate the antibacterial and antioxidant activities of bio-fermented Sanguisorbae Radix extract.Methods : The Sanguisorbae Radix extract was fermented byStreptococcus thermophilus,and their products was tested for antibacterial activity against pathogenic microorganisms namely,Bacillus cereus,Bacillus subtilis,Staphylococcus aureus,Escherichia coli,Vibrio parahaemolyticusandSalmonella typhimuriumby paper disc diffusion method and the antioxidant activities of extract was evaluated by five different assays as electron donating ability(EDA), superoxide dismutase(SOD)-like activity, polyphenol, flavonoid contents and nitrite scavenging ability.Results : The bio-fermented Sanguisorbae Radix extract was safe from heat. Antibacterial activity of fermented Sanguisorbae Radix extract appeared relatively highly againstBacillus cereusandStaphylococcus aureusand didn't show any difference. EDA in comparison to Vitamin C showed over 90% activity at about the same time of Sanguisorbae Radix extract expressed highly. SOD activity showed 15% in fermentation before and after. The nitrite scavenging ability of Sanguisorbae Radix extract before and after fermentation showed higher numerical value over 70% in pH 2.5 than that of butylated hydroxytoluene(BHT). But SOD activity, EDA and nitrite scavenging ability were not different between the Sanguisorbae Radix extract before and after fermentation. Total polyphenol content expressed over about 20 mg/g, and that of the Sanguisorbae Radix extracts was increased than that of the fermented Sanguisorbae Radix extracts.Conclusions : The results suggest the usefulness of developing functional materials using antioxidant active Sanguisorbae Radix extract was fermented bySalmonella typhimuriumwith high polyphenol contents and nitrite scavenging ability.