• 생약학회지
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• 제29권3호
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• pp.155-158
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• 1998

In the Asian sub-continent Momordica charantia and Allium sativum are extensively used as food and are popular in herbal medicine. The two were screened against 15 pathogens and both exhibited broard spectrum antimicrobial activity. As compared to the standard antibiotics, M. charantia demonstrated broader and higher level of activity against most of the organisms. On the other hand A. sativum showed comparable activity to the standard antibiotics. Both M. Charantia and A. sativum are proposed as non toxic, safe, broad spectrum antibacterial agents.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.669-671
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• 2000

Antimicrobial cationic peptides have attracted increasing research and clinical interest as a natural antibiotics due to their broad spectrum of antimicrobial activites and the rapid development of multidrug-resistant pathogenic microorganisms. In this study, first, we synthesized artificial fusion partner and cationic peptide genes (lactoferricin, magainin, protegrin-1, and indolicidin). Second, we constructed recombinant expression vectors and then transformed Pichia pastoris. Finally, expressed cationic peptides were purified and tested for their antimicrobial activites. Antimicrobial activity has been tested upon the appearance of clearing zone on the plate with the lawn of gram negative E.coli XL- I blue and garm positive Staphylococcus aureus. Protegrin-1 and Indolicidin have apparant activity of cationic peotides. This fusion technique may lead to a general and suitable tool for production of pure antimicrobial cationic peptides in Pichia pastoris.

• BMB Reports
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• 제29권6호
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• pp.545-548
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• 1996

CA(1-8)ME(1-12), the CA-ME hybrid peptide of the amino terminal segments of cecropin A (CA) and melittin (ME), has been reported to have a broad spectrum and improved potency without a hemolytic property. In order to obtain new synthetic peptides with powerful antibacterial activity without hemolytic activity, several hybrid peptides were designed from the sequences of CA, ME, magainin 2, bombinin and lactoferricin. All hybrid peptides were constructed to form an amphipathically basic-flexible-hydrophobic structure and synthesized by the solid phase method. Their hemolytic activities against human red blood cells and antibacterial activities against both Gram-positive and Gram-negative bacteria were detennined. CA(1-8)MA(1-12), CA(1-8)BO(1-12), MA(10-17)ME(1-12) and LF(20-29)ME(1-12) showed comparable activities with broad spectra against both Gram-positive and Gram-negative bacteria relative to CA(1-8)ME(1-12) but without hemolytic properties. These hybrid peptides, therefore, could be useful as model peptides to design a novel peptide with improved antibacterial activity and study on structure-activity relationships of antimicrobial peptides.

• 미생물학회지
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• 제44권4호
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• pp.326-332
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• 2008

국내 토양으로부터 MRSA에 대해 항균활성을 보이는 세균들을 분리하였다. 이들 가운데 가장 높은 항MRSA 균 활성을 보인 YK5 균주는 호기성 간균으로 운동성이 있고, 내생포자를 형성하였으며, 인돌을 형성하지 않았고, mannitol을 분해하여 산을 생성시키지 않았다. 이 균주의 16S rRNA 유전자 염기서열은 Paenibacillus 속 세균들의 유전자와 $95{\sim}98%$의 상동성을 나타냈는데 특히 P. elgii와 가장 높은 상동성을 보였으나, 기타 생리 생화학적 특성에서 다른 점들이 관찰되어 P. incheonensis YK5로 명명되었다. P. incheonensis YK5 를 SST 배지에 접종하여 $37^{\circ}C$에서 96 시간 배양한 다음 그 상등액으로 부터 부탄올로 추출된 항균물질은 그람 양성균인 MRSA 20 균주들과 Streptococcus pneumoniae, 그람 음성균인 Pseudomonas aeruginosa 10균주들, Salmonella spp., Shigella spp., Escherichia coli와 Klebsiella pneumoniae 및 인체병원성 진균인 Cryptococcus neoformans와 Trichophyton spp.에 대하여 광범위한 항균효과를 나타냈다. 또한 이 항균물질은 $20{\sim}100^{\circ}C$ 사이의 온도구간에서 안정한 활성을 유지하였을 뿐만 아니라, pH $3.0{\sim}7.0$의 넓은 pH범위에서 활성을 나타내 MRSA를 비롯한 다양한 병원균에 대한 항생물질로서의 가능성을 보였다.

• 대한치과의사협회지
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• 제41권2호통권405호
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• pp.116-123
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• 2003

Antimicrobial Peptides are natural antibiotics evolved by many plants, invertebrate, and vertebrate to defend against the microbial infection. Antimicrobial peptides show a broad-spectrum antimicrobial activity with little opportunity for the development of resistance since they target microbial membranes that distinguish microbes from enkaryotic cells. The oral cavity is constantly exposed to microbial challenges and antimicrobial peptides play an important role in managing the oral health. With the increase of resistant micro-organisms to conventional antibiotics, antimicrobial peptides are attracting interests as novel antibiotics. In this review, the characteristics of antimicrobial of antimicrobial peptides including the classification, mechanism of action, resistance, and expression in the oral cavity have been discussed in the prospects of application to oral disease.

• 한국미생물·생명공학회지
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• 제39권1호
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• pp.1-8
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• 2011

The antimicrobial effects of silver (Ag) ion or salts are well known. Recently, silver nanoparticle is attracting an interest in a wide variety of fields since it has been known to be safe and effective as an antimicrobial agent against a broad spectrum of microorganisms. Although silver nanoparticle has been applied to various kinds of products owing to its potent antimicrobial activity, the effects of silver nanoparticle on microorganisms and antimicrobial mechanism have not been revealed clearly. In this paper, we summarized the characteristics, antimicrobial activities and mechanisms, cytotoxicity and applicability of silver nanoparticle.

• 한국약용작물학회지
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• 제28권1호
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• pp.38-46
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• 2020

Background: Although Sancho (Zanthoxylum schinifolium Siebold & Zucc) oil has traditionally been used for its antibiotics properties, there is currently a lack of scientific evidence regarding its biological activities. In this study, we investigated the antimicrobial and antioxidant activities of Sancho oil against food-hazardous microorganisms, phytopathogens, and dermatophytes. Methods and Results: We investiated the antimicrobial activity of Sancho oil against 11 food-hazardous microorganisms, nine phytopathogens, and six dermatophytes. The Sancho oil was found to show the strongest antibacterial activity against Shigella flexneri and Listeria spp. Sancho oil also showed high antifungal activity against plant pathogens, particularly Fusarium oxysporum, and showed antimicrobial activity against dermatophytes such as Trichophyton rubrum, Microsporum canis and Candida albicans. The antioxidant activity of Sancho oil was measured using the DPPH method, and was found to be stronger than that of unrefined oil. Moreover, this activity increased with increasing oil concentration. Conclusions: We found that Sancho oil showed differing antimicrobial activities against food-hazardous microorganisms, dermatophytes, and plant pathogens. The antimicrobial activity spectrum of Sancho oil was not broad and varied among microbial strains. On the basis of our findings, we consider that Sancho oil could be used an antibacterial material for food-borne S. flexneri and Listeria spp., a biopesticide for Fusarium spp., and a treatment for dermatophytes such as T. rubrum.

• 대한약침학회지
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• 제24권1호
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• pp.32-40
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• 2021

Objectives: Pathogenic microbes are causal agents for various types of severe and even lethal infectious diseases. Despite of development in medication, bacterial and fungal infections still persist to be a vital problem in health care. Bacteria and several fungal species have shown resistance to antibiotics used in treatment to current medications. Therefore, it is a considerable field of interest in the design and development of novel compounds with antimicrobial activity. Methods: The compounds bearing a heterocyclic ring play an imperative role among other organic compounds with pharmacological activity used as drugs in human for control and cure of various infections. Thiadiazoles containing nitrogen-sulfur atom as part of their cyclic structure which shown wide-ranging application as structural units of biologically active molecules and are very useful intermediates in Medicinal Chemistry. Results: The effectiveness of the thiadiazole nucleus was established by the drugs currently used for the treatment of various infections. 1,3,4-Thiadiazoles and some of their derivatives are widely studied because of their broad spectrum of pharmacological activities. Conclusion: In the present work, a series of 1,3,4-Thiadiazole derivatives were synthesized by cyclization of a group of various benzaldehyde with thiosemicarbazide in the presence of various reagent like FeCl3, HCHO by losing a molecule of water. These derivatives were found to possess prominent antimicrobial activity.

• 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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• 제29권5호
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• pp.731-738
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• 2019

Endophytic fungi are an important component of plant microbiota, and have the excellent capacity for producing a broad variety of bioactive metabolites. These bioactive metabolites not only affect the survival of the host plant, but also provide valuable lead compounds for novel drug discovery. In this study, forty-two endophytic filamentous fungi were isolated from Ficus elastica leaves, and further identified as seven individual taxa by ITS-rDNA sequencing. The antimicrobial activity of these endophytic fungi was evaluated against five pathogenic microorganisms. Two strains, Fes1711 (Penicillium funiculosum) and Fes1712 (Trichoderma harzianum), displayed broad-spectrum bioactivities. Our following study emphasizes the isolation, identification and bioactivity testing of chemical metabolites produced by T. harzianum Fes1712. Two new isocoumarin derivatives (1 and 2), together with three known compounds (3-5) were isolated, and their structures were elucidated using NMR and MS. Compounds 1 and 2 exhibited inhibitory activity against Escherichia coli. Our findings reveal that endophytic fungi from the rubber tree F. elastica leaves exhibit unique characteristics and are potential producers of novel natural bioactive products.