• Journal of Microbiology and Biotechnology
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• 제27권6호
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• pp.1078-1089
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• 2017

Biofilm formation of Staphylococcus aureus is one of its mechanisms of drug resistance. Anti-biofilm screening of 106 compounds from marine-derived fungi displayed that 12 compounds inhibited S. aureus biofilm formation by >50% at the concentration of $100{\mu}g/ml$, and only secalonic acid D (SAD) and B inhibited by >90% at $6.25{\mu}g/ml$ without inhibiting cell growth after 24-h incubation. Meanwhile, it was found that the double bond between C-1 and C-10 of citrinin derivatives and the C-C connection position of two chromone monomers may be important for their anti-biofilm activities. Moreover, SAD slightly facilitated biofilm eradication and influenced its architecture. Furthermore, SAD slowed the cell growth rate in the preceding 18-h incubation and differentially regulated transcriptional expression of several genes, such as agr, isaA, icaA, and icaD, associated with biofilm formation in planktonic and biofilm cells, which may be the reason for the anti-biofilm activity of SAD. Finally, SAD acted synergistically against S. aureus growth and biofilm formation with other antibiotics. These findings indicated that various natural products from marine-derived fungi, such as SAD, could be used as a potential biofilm inhibitor against S. aureus.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.261-261
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• 2005

• 한국수산과학회지
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• 제57권1호
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• pp.15-22
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• 2024

This study assessed microbial contamination in seven fried fish pastes sold in Southeast Asian traditional markets during summer. It measured viable cell count, coliforms, Escherichia coli, fungi, and Staphylococcus spp. It also qualitatively analyzed Vibrio parahaemolyticus, Salmonella spp., Bacillus cereus, Listeria monocytogenes, and Clostridium perfringens. The average viable cell count, coliforms and fungi were detected as 6.34 (3.84-8.13), 2.16 (1.00-3.55), and 3.92 (1.85-7.74) log₁₀ CFU/g, respectively. Staphylococcus spp. was detected at 4.59 (2.10-7.63) log₁₀ CFU/g. Some samples had high contamination levels: viable cell count (8.13 log₁₀ CFU/g), fungi (7.74 log₁₀ CFU/g) and S. aureus (7.63 log₁₀ CFU/g). However, E. coli was not detected in any samples (ND, <1 log₁₀ CFU/g). V. parahaemolyticus, Salmonella spp., B. cereus, L. monocytogenes, and Cl. perfringens were also not detected in the samples. The microbial contamination data provide insight into managing microbial contamination and ensuring the safety of fried fish pastes in traditional summer markets.

• 생약학회지
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• 제33권3호통권130호
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• pp.219-223
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• 2002

In order to screen new radical scavenging principle which is expected to be antiaging drug lead, we have isolated 160 strains of the marine-derived fungi and investigated 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity for their acetone extracts. The significant activities (>50% Inhibition) were observed in 8 strains of fungi (MFA006, MFA0l4, MFA040, MFA133, MFA139, MFA143, MFA148, MFA153), and among them, MFA153 (Aspergillus parasiticus) showed the most significant radical scavenging activity. The active components were purified by assay-guided isolation to yield two known benzyl alcohols, l53B3 (1) and l53B4 (2), and their structures were determined by physicochemical evidence. Two compounds (1,2) showed the significant radical scavenging activity with $IC_{50}$ values of 0.6 and $1.4{\mu}M$ against DPPH, respectively.

• 한국해양생명과학회지
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• 제8권2호
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• pp.136-149
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• 2023

우리나라 여러 해양환경 지역으로부터 확보한 370주의 해양세균, 균류, 미세조류로부터 기초생리활성(항산화, 항염, 항균, 항암, 항바이러스)을 조사하여 채집지, 분리원, 종(種) 수준에서의 활성결과를 비교하였다. 해양세균의 경우, 일반적으로 유용성이 많이 알려진 Streptomyces 속과 Bacillus 속에 속하는 균주들이 두드러진 강한 효능이 관찰되었고, 주로 해양퇴적물로부터 유용한 자원을 분리할 수 있었다. 해양균류와 미세조류의 경우에도 종 특이적으로 활성이 강하게 나타나는 결과를 확인할 수 있었고, 효능 특이적으로 활성을 보이는 결과도 얻을 수 있었다. 이러한 결과를 바탕으로 추후 특정질병에 선택적으로 효능을 보이는 화학물질 연구 또는 자원 기반 연구 수행 시 유용성을 전제로 한 자원 확보 전략 수립과 산업 활성화를 위한 전략소재로 우선적 접근이 용이할 수 있는 연구결과라 생각된다. 또한, 이들 결과를 해양바이오 뱅크를 통한 분양소재로 활용함으로써 학계, 산업계에서 활용하여 해양바이오산업 활성화에 좀 더 빠른 접근을 도울 수 있다고 생각한다.

• Mycobiology
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• 제51권6호
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• pp.436-444
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• 2023

Aspergillus species play a crucial role in terrestrial environments as degraders and are well known for producing various secondary metabolites. Recently, Aspergillus species have been discovered in marine environments, exhibiting adaptability to high salinity and producing diverse secondary metabolites with valuable properties. However, limited research has focused on their marine diversity, leading to inaccurate species identification. The current study addresses this gap by investigating diverse marine habitats in the Republic of Korea, including sediment, seawater, seaweed, and marine animals. From three coasts of the Korean Peninsula, 472 Aspergillus strains were isolated from the various marine habitats. A total of 41 species were accurately identified using multigenetic markers: internal transcribed spacer, calmodulin, and b-tubulin. The findings underscore the importance of accurate identification and provide a basis for elucidating the functional role of marine-derived Aspergillus species in marine ecosystems.

• Fisheries and Aquatic Sciences
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• 제5권2호
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• pp.97-102
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• 2002

Pyricularia oryzae (P. oryzae), the cause of rice blast, is one of the most important fungal pathogens of rice. Seventy strains of marine fungi were isolated from marine algae, and it was measured antifungal activity against P. oryzae. Metabolites of marine fungus A-248 which isolated from marine algae showed strong antifungal activity against P. oryzae. The antifungal substance from the metabolites of marine fungus A-248 was extracted with ethylacetate, and then purified by preparative TLC and reverse-phase HPLC. The minimum inhibitory concentration (MIC) value was $0.18\mu g/mL$ for the antifungal activity of the substance purified from A-248 metabolites. The purified substance was similar to antifungal activity of rhizoxin, which is a commercial antifungal agent.

• Journal of Microbiology and Biotechnology
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• 제24권10호
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• pp.1337-1345
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• 2014

A novel antifungal protein produced by the fungal strain Penicillium citrinum W1, which was isolated from a Southwest Indian Ocean sediment sample, was purified and characterized. The culture supernatant of P. citrinum W1 inhibited the mycelial growth of some plant pathogenic fungi. After saturation of P. citrinum W1 culture supernatants with ammonium sulfate and ion-exchange chromatography, an antifungal protein (PcPAF) was purified. The N-terminal amino acid sequence analysis showed that PcPAF might be an unknown antifungal protein. PcPAF displayed antifungal activity against Trichoderma viride, Fusarium oxysporum, Paecilomyces variotii, and Alternaria longipes at minimum inhibitory concentrations of 1.52, 6.08, 3.04, and $6.08{\mu}g/disc$, respectively. PcPAF possessed high thermostability and had a certain extent of protease and metal ion resistance. The results suggested that PcPAF may represent a novel antifungal protein with potential application in controlling plant pathogenic fungal infection.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2345-2350
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• 2009

As part of an effort to discover bioactive natural products from marine sources, we investigated the bioactive secondary metabolites from two marine isolates of the fungi, Trichoderma viride and Rhizopus stolonifer. Three cyclopentenones, myrothenones A (1) and B (2) and trichodenone A (3), were isolated from T. viride and two cyclopentenones, 2-bromomyrothenone B (4) and botrytinone (5), were isolated from R. stolonifer. The molecular structures and absolute stereochemistries of the cyclopentenones were determined from chemical and physicochemical evidence, including quantum chemistry calculations, X-ray analysis, and the circular dichroism (CD) exciton chirality method. Myrothenone A (1) displays tyrosinase inhibitory activity, with an I$C_{50}$ value of 6.6 ${\mu}M$, and is therefore more active than the positive control, kojic acid.

• Mycobiology
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• 제49권6호
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• pp.551-558
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• 2021

The Federated States of Micronesia (FSM) is an island country in the western Pacific and is a known biodiversity hotspot. However, a relatively small number of fungi (236 species) have been reported till July 2021. Since fungi play major ecological roles in ecosystems, we investigated the fungal diversity of FSM from various sources over 2016 and 2017 and constructed a local fungal inventory, which also included the previously reported species. Fruiting bodies were collected from various host trees and fungal strains were isolated from marine and terrestrial environments. A total of 99 species, of which 78 were newly reported in the FSM, were identified at the species level using a combination of molecular and morphological approaches. Many fungal species were specific to the environment, host, or source. Upon construction of the fungal inventory, 314 species were confirmed to reside in the FSM. This inventory will serve as an important basis for monitoring fungal diversity and identifying novel biological resources in FSM.