• 한국미생물·생명공학회지
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• 제39권2호
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• pp.168-174
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• 2011

본 연구에서는 안전하고 효율적인 항진균제 개발 연구의 일환으로 73종의 약용 및 식용식물의 메탄올 추출물을 조제하고 이들의 hexane, methylene chloride, ethylacetate, butanol 분획물 및 water 잔류물 365종을 각각 조제하여 Aspergillus niger에 대한 항진균력을 조사하였다. 활성 선별단계에서 비교적 경제적이면서도 손 쉬운 순차적 유기용매 분획물을 제조하여 항진균 천연물 탐색을 시도함으로서 기존에 천연물 추출물에서 검색되지 않은 참나물, 뽕나무, 단삼의 항진균 활성을 확인하였다. 특히 항진균 활성이 보고된 바 없는 참나물의 경우 methylene chloride 분획에서 A. niger에 대한 MIC, MFC 가 각각 0.25 및 0.5 mg/mL임을 확인하여 강력한 항진균 활성을 확인하였으며, 0.25 mg/mL 농도에서 포자발아 억제활성도 나타냄을 확인하였다. 또한 활성분획은 0.5 mg/mL농도까지 인간 적혈구에 대해 용혈활성을 나타내지 않았으며, 활성물질은 당이 결합된 flavonoid로 추측되었다. 본 연구결과는 참나물 methylene chloride 분획의 우수한 항진균 활성을 제시하며, 비교적 간단한 유기 용매 분획법을 이용한 천연물 시료제조 및 이를 이용한 활성탐색이 새로운 활성물질 선별에 효과적임을 제시하고 있다.

• Archives of Pharmacal Research
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• 제23권1호
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• pp.46-49
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• 2000

Two neolignan compound, magnolol $(5,5^{l}-diallyl-2,2^{l}-dihydroxybiphenyl, 1)$ and honokiol $(5,5^{l}-diallyl-2,4^{l}-dihydroxybiphenyl, 2)$ were isolated from the stem bark of Magnolia obovata and evaluated for antifungal activity against various human pathogenic fungi. Compound 1 and 2 showed significant inhibitory activities against Trichophyton mentagrophytes, Microsporium gypseum, Epidermophyton floccosum, Aspergillus niger, Cryptococcus neoformans, and Candida albicans with minimum inhibitory concentrations (MIC) in a range of $25-100{\mu}g/ml$. Therefore, compound 1 and 2 could be used as lead compounds for the development of novel antifungal agents.

• Food Science and Biotechnology
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• 제14권4호
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• pp.487-492
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• 2005

Simple competition plate bioassays of Pichia anomala SKM-T and Galactomyces geotrichum SJM-59 were conducted to evaluate their potential as biological control agents that inhibit growth of Botrytis cinerea during post-harvest storage of strawberries (Fragaria ${\times}$ ananassa Duche, Red-Pearl). Occurrence rates of fungi on the surface of yeast-treated strawberries were evaluated during storage at $4^{\circ}C$. P. anomala SKM-T and G. geotrichum SJM-59 showed antifungal activities on agar plate, and P. anomala SKM-T maintained its desirable antifungal activity on surface of strawberries and its physicochemical properties during storage. Sensory evaluation was based on kinesthetics and consumer acceptability. Due to its potential antifungal activity, P. anomala SKM-T could function as biological control agent against spoilage fungi during post-harvest storage of strawberries.

• 생명과학회지
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• 제14권6호
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• pp.1003-1008
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• 2004

11 plant essential oils are screened in vitro for their antifungal activities against Botrytis cinerea, Fusarium oxysporum and Rhizoctonia solani, which are causative agents of serious plant diseases. The radial growth of the test fungi were reduced in response to the oils. Among them, the essential oil from the bark of Cinnamomum zeylanicum inhibited 3 tested fungi growth, strongly, followed by those of oregano and thyme. The major constituents of the three essential oils, cinnaldehyde, carvacrol and thymol were tested for their effects on the fungi. From the results obtained, cinnamaldehyde, the major constituents of C. zeylanicum bark esential oil, has potential to be developed as a biopesticide for controlling phytopathogenic fungi causing serious damages on the important crops cultivated in Korea.

• 대한미생물학회지
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• 제19권1호
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• pp.35-40
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• 1984

The effectiveness of three antifungal antibiotics amphotericin B, clotrimazole and 5-fluorocytosine was tested against 120 clinical isolated Candida species. The minimum inhibitory concentrations of amphotericin B was considerably lower than those of clotrimazole and 5-fluorocytosine. High-level resistance to 5-fluorocytosine was present in 50% of the isolates. The combination of clotrimazole and 5-fluorocytosine produced synergistic inhibition against all 20 strains of Candida albicans tested that were relatively resistant to both antifungal agents.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.99.2-99
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• 2003

An attempt was made to screen antifungal activities of Bacillus thuringiensis strains on various plant pathogens, Botryosphaeria dothidea, Diaporthe actinidiae, Botrytis cinerea, Glomerella cingulata, Colletorichum cocodes, Sclerotinia scierotiorum, Alternaria alternata, Helicobuidium mompa, Bipolaris coicis, Fusarium graminearum and Rhizoctosnia solani. Ten and forty-five strains of B. thuringiensis were isolated from animal feces in Korea and Japan, respectively. Inhibitory effects of the strains on the mycelial growth of the pathogens were examined on the mixed media of potato dextrose agar and nutrient agar. Approximately half of the strains inhibited the mycelial growth of one or more pathogens. Most of the pathogens were inhibited by any of the strains but Fusarium graminearum and Rhizoctonia solani were not inhibited at all. This is the first report that B. thuringiensis shows a potent antifungal activity on plant pathogens in Korea.

• The Plant Pathology Journal
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• 제40권3호
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• pp.322-328
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• 2024

Soybean (Glycine max), a crucial global crop, experiences yearly yield reduction due to diseases such as anthracnose (Colletotrichum truncatum) and root rot (Fusarium spp.). The use of fungicides, which have traditionally been employed to control these phytopathogens, is now facing challenges due to the emergence of fungicide-resistant strains. Streptomyces bacillaris S8 strain S8 is previously known to produce valinomycin t through a nonribosomal peptide synthetase (NRPS) pathway. The objective of this study was to evaluate the antifungal activity of S. bacillaris S8 against C. truncatum and Fusarium sp., assessing its efficacy against soybean pathogens. The results indicate that strain S8 effectively controlled both above-ground and underground soybean diseases, using the NRPS and NRPS-related compound, suggesting its potential as a biological control in plant-microbe interactions. These findings underscore the pivotal role of the stain S8 in fostering healthy soybean microbial communities and emphasize the significance of microbiota structure studies in unveiling potent biocontrol agents.

• Applied Biological Chemistry
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• 제42권4호
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• pp.271-276
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• 1999

새로운 천연물 농약 또는 생산군주를 개발하기 위하여 Streptomyces 속의 여러 균주를 대상으로 항진균 물질을 탐색하여 항진균 물질 생산 균주 Streptomyces hygroscopicus MJM1004를 선발하였다. 항진균 물질의 생산을 위한 발효 배지를 선정하기 위하여 여러 탄소원, 질소원과 무기원을 대상으로 균체 생장 정도와 항진균 물질의 생산성을 조사하였으며, 생산 배지는 2% soybean meal, 1% glucose, 2% starch, 0.3% $CaCO_3$, 0.05% $MgSO_4{\cdot}7H_2O$, 0.05% $K_2HPO_4$를 조성으로 하였다. S. hygroscopicus MJM1004 균주의 균체에서 추출된 항진균 물질은 Candida albicans와 여러 식물 병원성 곰팡이들에 대하여 광범위한 저해 효과를 나타내었다. S. hygroscopicus MJM1004 균체로부터 분리된 항진균 물질, SH-1004를 핵자기공명법($^1H,\;^{13}C$, DQF COSY, HMQC 및 HMBC)을 통하여 분석한 결과 azalomycin F complex 임을 확인할 수 있었다. Positive FAB mass spectrum을 통하여 SH-1004는 azalomycin F4a와 F5a가 1.8 : 1의 비율로 혼합된 물질임을 확인하였다.

• 한국임상약학회지
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• 제28권3호
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• pp.181-187
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• 2018

Background: Posaconazole is a broad-spectrum triazole antifungal agent and the most recommended prophylactic antifungal agent for patients with acute myeloid leukemia (AML) undergoing induction chemotherapy. In this study, we evaluated the status and effectiveness of posaconazole as a prophylactic antifungal agent in pediatric patients receiving induction chemotherapy for AML. Methods: We retrospectively reviewed the electronic medical records of 36 pediatric patients with AML (between January 2013 and September 2017) at the Yonsei University Health System. Invasive fungal disease (IFD) was assessed as the primary endpoint of prophylactic antifungal effect. The secondary endpoints were incidence of fever, persistent fever despite the use of broad-spectrum antibiotics for 72 h, alteration of antifungal agent, intensive care unit admission, and death within 100 days. Results: Among the 36 patients, 18 patients used posaconazole, 12 were treated with suspension formula, and 6 of them were treated with tablets. Eighteen patients did not use antifungal agents prophylactically. The mean number of days of posaconazole administration was $26.8{\pm}16days$. IFD occurred in 2/18 (11.1%) patients in the no prophylaxis group and in 1/18 (5.6%) patients in the posaconazole group (p=0.49). Conclusion: Posaconazole is expected to be useful for the prevention of IFD in pediatric patients with AML undergoing induction chemotherapy. Prospective studies of the effectiveness of posaconazole prophylaxis should be conducted in more pediatric patients in the future.

• Journal of Microbiology and Biotechnology
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• 제18권10호
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• pp.1729-1734
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• 2008

Chitosan, a cationic polysaccharide, has been widely used as a dietary supplement and in a variety of pharmacological and biomedical applications. The antifungal activity and mechanism of action of low molecular weight water-soluble chitosan (LMWS-chitosan) were studied in fungal cells and vesicles containing various compositions of fungal lipids. LMWS-chitosan showed strong antifungal activity against various pathogenic yeasts and hyphae-forming fungi but no hemolytic activity or cytotoxicity against mammalian cells. The degree of calcein leakage was assessed on the basis of lipid composition (PC/CH; 10:1, w/w). Our result showing that LMWS-chitosan interacts with liposomes demonstrated that chitosan induces leakage from zwitterionic lipid vesicles. Confocal microscopy revealed that LMWS-chitosan was located in the plasma membrane. Finally, scanning electron microscopy revealed that LMWS-chitosan causes significant morphological changes on fungal surfaces. Its potent antibiotic activity suggests that LMWS-chitosan is an excellent candidate as a lead compound for the development of novel anti-infective agents.