• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.453-456
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• 2000

감귤의 저온저장 중 부패방지를 위한 천연항균제 개발의 일환으로 감귤의 저온저장 중 과피로부터 분리한 곰팡이를 MEA와 PDA 배지에서 배양하면서 분생자병과 분생자의 형태적 특성을 조사한 결과 플라스크형의 phialide, 분생자병의 branching type이 simple type이며, conidial head가 columnar shape 등의 특징을 갖는 Penicillium sp. CF-301로 동정되었다. 또한 국내 자생식물을 채집하여 유기용매로 추출한 후 향균활성을 조사한 결과 측백나무 열매와 주목나무를 제외한 8종의 식물 추출액이 감귤부패균에 대하여 향균활성을 보였으며, 특히 측백나무 즙액은 8mm의 투명환을 보여 가장 높은 항균활성을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제16권3호
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• pp.349-354
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• 2006

Furaneol, a key aroma compound found in strawberry, pineapple, and processed foodstuffs, has been known to possess various biological activities on animal models. In this study, the antimicrobial effects of furaneol against human pathogenic microorganisms were investigated. The results indicated that furaneol displayed a broad spectrum of antimicrobial activities against Gram-positive and Gram-negative bacteria and fungi without hemolytic activity on human erythrocyte cells. To confirm the antifungal activity of furaneol, we examined the accumulation of intracellular trehalose as a stress response marker on toxic agents and its effect on dimorphic transition of Candida albicans. The results demonstrated that furaneol induced significant accumulation of intracellular trehalose and exerted its antifungal effect by disrupting serum-induced mycelial forms. These results suggest that furaneol could be a therapeutic agent having a broad spectrum of antimicrobial activity on human pathogenic microorganisms.

• 한국미생물·생명공학회지
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• 제47권4호
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• pp.651-661
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• 2019

Targeting the pathogen viability using drugs is associated with development of drug resistance due to selective pressure. Hence, there is an increased interest in developing agents that target bacterial virulence. In this study, the inhibitory effect of ciclopirox, an antifungal agent with iron chelation potential, on the microbial virulence factors was evaluated in 26 clinical MDR Pseudomonas aeruginosa isolates collected from Alexandria Main University Hospital, a tertiary hospital in Egypt. Treatment with 9 ㎍/ml ciclopirox inhibited the hemolytic activity in 70% isolates, reduced pyocyanin production, decreased protease secretion in 46% isolates, lowered twitching and swarming motility, and decreased biofilm formation by 1.5- to 4.5-fold. The quantitative real-time PCR analysis revealed that treatment with ciclopirox downregulated the expression levels of alkaline protease (aprA) and pyocyanin (phzA1). Ciclopirox is used to treat hematological malignancies and the systemic administration of ciclopirox is reported to have adequate oral absorption with a satisfactory drug safety profile. It is important to calculate the appropriate clinical dose and therapeutic index to reposition ciclopirox from a topical antifungal agent to a promising virulence-modifying agent agent against P. aeruginosa, a problematic Gram-negative pathogen.

• Journal of Microbiology and Biotechnology
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• 제20권1호
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• pp.138-145
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• 2010

A bacterial strain isolated from soil for its potential to control the anthracnose disease caused by Colletotrichum gloeosporioides was identified as a Bacillus subtilis. Bacillus subtilis CMB32 produced antifungal agents on M9 broth at $30^{\circ}C$. Biosurfactant lipopeptides produced by Bacillus subtilis CMB32 were precipitated by adjusting to pH 2 and extracting using chloroform/methanol, and then were purified using column chromatography and reverse-phase HPLC. The molecular masses of the lipopeptides were estimated by MALDI-TOF mass spectrometry as (a) 1,080, (b) 1,486, and (c) 1,044 Da, respectively. They had cyclic structures and amino acid compositions of (a) Pro, Asx, Ser, Tyr, Glx, (b) Glx, Tyr, Thr, Ala, Pro, lie, and (c) Glx, Leu, Val, Asx, respectively. Further analysis revealed that Bacillus subtilis CMB32 produced three antifungal lipopeptides: (a) iturin A, (b) fengycin, and (c) surfactin A.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.729-732
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• 2000

양파의 저온저장중 부패방지를 위한 천연항균제 개발의 일환으로 저장양파로부터 부패세균을 분리한 후 이 균에 대한 식물추출물의 항균활성을 조사하였다. 양파의 저온저장중 과육으로부터 분리한 곰팡이를 MEA와 PDA에서 배양하면서 분생자병과 분생자의 형태적 특성을 조사한 결과 플라스크형의 phialide, 분생자병의 branching type이 simple type이며, conidial head가 columnar shape 가지고 있는 것으로 확인되어 Penicillium sp. ON-211으로 동정하였다. 또한 자생 식물은 채집하여 각종 유기용매로 추출한 후 항균활성을 조사하였다. 정향나무, 탱자나무의 잎은 chloroform 분액에서 높은 활성을 나타내었고, 측백나무 열매는 물분획에서 높은 활성을 나타내었으며, 연필향나무의 잎은 ethyl acetate 분획에서 비교적 높은 항균 활성이 나타났다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제39권5호
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• pp.246-250
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• 2013

Rhinocerebral mucormycosis (RCM) is an opportunistic, potentially life-threatening fungal disease. This infective disease invades not only the facial sinuses, but also the maxilla, zygoma, and rhino-cerebral structures with a massive destruction of the facial skeletons and soft tissue. This disease progresses within various underlying diseases, such as diabetes mellitus, hematologic malignancy, renal failure, and systemic immunodepression. The relationship between mucormycosis and these underlying conditions have been discussed extensively in the literature. The authors studied 6 cases of RCM diagnosed by a tissue biopsy and treated at the department of oral and maxillofacial surgery, from 1997 to 2012. Patients were treated with several kinds of surgical interventions and antifungal agents, and their clinical & radiological signs, underlying conditions, surgical methods, and outcomes were analyzed.

• The Plant Pathology Journal
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• 제32권3호
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• pp.273-280
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• 2016

Most biocontrol agents for plant diseases have been isolated from sources such as soils and plants. As an alternative source, we examined the feces of tertiary larvae of the herbivorous rhino beetle, Allomyrina dichotoma for presence of biocontrol-active microbes. The initial screen was performed to detect antifungal activity against two common fungal plant pathogens. The strain with strongest antifungal activity was identified as Bacillus amyloliquefaciens KB3. The inhibitory activity of this strain correlated with lipopeptide productions, including iturin A and surfactin. Production of these surfactants in the KB3 isolate varied with the culture phase and growth medium used. In planta biocontrol activities of cell-free culture filtrates of KB3 were similar to those of the commercial biocontrol agent, B. subtilis QST-713. These results support the presence of microbes with the potential to inhibit fungal growth, such as plant pathogens, in diverse ecological niches.

• 약학회지
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• 제41권2호
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• pp.187-194
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• 1997

For the development of antifungal agents, modification of naftifine which exhibits significant antimycotic activity was performed by replacing the naphthalene ring of it to hete ro cyclic rings such as morpholine. benzothiazole, piperidine and pyridine derivatives. The synthesized compounds were tested in vitro antifungal activity against five different fungi with naftifine as a comparative antimycotic molecule. From the biological evaluation two compounds, (E)-N-(3-phenyl-2-propenyl)-N-(4-piperidinylmethyl)amine(3d) and (E)-N-(3-phenyl-2-propenyl)-N-(3-pyridylmethyl)amine(3f) showed relatively noticeable activity(MIC=50${\mu}g$/ml). On the other hand, the other compounds had no activity.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.216-220
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• 2005

Periconicin A and B, two new fusicoccane diterpenes originally isolated from the cultures of endophytic fungus Periconia sp. OBW-15, were tested by several biological assays. Periconicin A was consistently more active than periconicin B. In an antifungal activity assay, periconicin A showed potent inhibitory activity against the agents of human mycoses, including Candida albicans, Trichophyton mentagrophytes, and T. rubrum, with minimum inhibitory concentration (MIC) in the range of 3.12- 6.25 $\mug$ /ml. In a plant growth regulatory activity assay, periconicins inhibited hypocotyl elongation and root growth of Brassica campestris L. and Raphanus sativus L. At concentrations below 1 μg/ml, however, both compounds accelerated root growth by 110- 135%. From these results, it is apparent that a methyl group positioned in a cyclopentane ring may play an important role in plant and fungal growth inhibitory activity.

• Mycobiology
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• 제41권3호
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• pp.164-166
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• 2013

A Bacillus sp. BS061 significantly reduced disease incidence of gray mold and powdery mildew. To identify the active principle, the culture filtrate was partitioned between butanol and water. The antifungal activity against B. cinerea was evident in the butanol-soluble portion, and active substances were identified as cyclic lipopeptides, iturin A series, by nuclear magnetic resonance spectrometry (NMR) and mass analysis. Interestingly, antifungal activity against powdery mildew was observed in the water-soluble portion, suggesting that cyclic lipopeptides have no responsibility to suppress powdery mildew. This finding reveals that biocontrol agents of Bacillus origin suppress gray mold and powdery mildew through the secretion of different bioactive substances.