• Mycobiology
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• 제45권4호
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• pp.240-254
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• 2017

Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity ($a_w$) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and $a_w$. This review discusses the effects of temperature and $a_w$ on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.

• Mycobiology
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• 제46권1호
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• pp.13-23
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• 2018

Depending on the mode of nutrition exploitation, major fungal guilds are distinguished as ectomycorrhizal and saprotrophic fungi. It is generally known that diverse environmental factors influence fungal communities; however, it is unclear how fungal communities respond differently to environment factors depend on fungal guilds. In this study, we investigated basidiomycetes communities associated with Quercus mongolica using 454 pyrosequencing. We attempted to detect guild pattern (ectomycorrhizal or saprotrophic fungal communities) by comparing the influence of geography and source (root and surrounding soil). A total of 515 mOTUs were detected from root (321) and soil (394) of Q. mongolica at three sites of Mt. Jeombong in Inje County. We found that patterns of diversity and community structure were different depending on the guilds. In terms of alpha diversity, only ectomycorrhizal fungi showed significant differences between sources. In terms of community structure, however, geography significantly influenced the ectomycorrhizal community, while source appeared to have a greater influence on the saprotrophic community. Therefore, a guildbased view will help to elucidates novel features of the relationship between environmental factors and fungal communities.

• Journal of Microbiology and Biotechnology
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• 제34권8호
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• pp.1551-1562
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• 2024

Fungi employ diverse mechanisms for iron uptake to ensure proliferation and survival in iron-limited environments. Siderophores are secondary metabolite small molecules with a high affinity specifically for ferric iron; these molecules play an essential role in iron acquisition in fungi and significantly influence fungal physiology and virulence. Fungal siderophores, which are primarily hydroxamate types, are synthesized via non-ribosomal peptide synthetases (NRPS) or NRPS-independent pathways. Following synthesis, siderophores are excreted, chelate iron, and are transported into the cell by specific cell membrane transporters. In several human pathogenic fungi, siderophores are pivotal for virulence, as inhibition of their synthesis or transport significantly reduces disease in murine models of infection. This review briefly highlights siderophore biosynthesis and transport mechanisms in fungal pathogens as well the model fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe. Understanding siderophore biosynthesis and transport in pathogenic fungi provides valuable insights into fungal biology and illuminates potential therapeutic targets for combating fungal infections.

• 설비공학논문집
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• 제24권12호
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• pp.852-857
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• 2012

Recently, the indoor air pollution by microbes such as fungi and mites have become a concern as important research topic on indoor air quality. Fungal growth is significantly affected by humidity. In this study, we examined the influence of relative humidity on the surface of building materials and the water content of building materials on the fungal growth rate by measuring the mycelium length of fungi in the fungal detector placed on the surface of building materials. As a result, even if the relative humidity on the surface of building materials is identical, the more water content of building materials is, the more fungi grow faster. It was suggested that fungal growth rate depends on not only the relative humidity on the surface of building materials but also the water content of building materials.

• Mycobiology
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• 제42권1호
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• pp.1-5
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• 2014

The typical life cycle of filamentous fungi commonly involves asexual sporulation after vegetative growth in response to environmental factors. The production of asexual spores is critical in the life cycle of most filamentous fungi. Normally, conidia are produced from vegetative hyphae (termed mycelia). However, fungal species subjected to stress conditions exhibit an extremely simplified asexual life cycle, in which the conidia that germinate directly generate further conidia, without forming mycelia. This phenomenon has been termed as microcycle conidiation, and to date has been reported in more than 100 fungal species. In this review, first, we present the morphological properties of fungi during microcycle conidiation, and divide microcycle conidiation into four simple categories, even though fungal species exhibit a wide variety of morphological differences during microcycle conidiogenesis. Second, we describe the factors that influence microcycle conidiation in various fungal species, and present recent genetic studies that have identified the genes responsible for this process. Finally, we discuss the biological meaning and application of microcycle conidiation.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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• pp.933-935
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• 2017

이 논문은 유도무기의 비행 중에, 공력가열을 받는 환경조건으로부터 유도무기를 보호하는 열방호용 코르크계 외부 인슈레이션 재료의 곰팡이 영향 연구에 관한 것이다. 필라멘트 와인딩 공법으로 제작된 복합재 연소관의 외부에 적층하는 코르크계 재료를 고려하였으며, 주어진 시스템에서의 효율적인 시스템 개발을 위해서 요구되는 요구조건 분석의 중요성을 고려하였다. 코르크계 복합재료를 유도무기용 복합재연소관의 외부 인슈레이션 재료로 사용하는데 요구되는 기본 요구조건에 대한 요구조건 분석에 의한 연구항목의 실험적 연구를 수행하였다. 해당 코르크계 재료의 곰팡이 영향 연구를 위해 곰팡이가 배양된 시편의 전단시편(QLS) 기계적물성 시험을 수행, 곰팡이 배양 전후의 결과와 비교하였으며, 곰팡이 발생 방지연구를 위해 곰팡이 방지페인트 유무에 따른 항곰팡이 효과발현을 공인기관 인증시험을 통해 확인하였다.

• 복식
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• 제53권5호
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• pp.23-31
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• 2003

The Purpose of this study was to isolate and identify fungi found in excavated clothes dating on the 16th century. As a result of microscoping with LPCB staining, seven isolated strains were classified-Acremonium strictum, Acremonium kiliense, Fonsecaea sp., Candida sp., Trichoderma sp., Cladosporium spp., Penicillium spp.. In the process of isolation and identification of fungi by the sort of textile, more fungi were found in cotton, cotton batt and silk than in ramie and hemp, suggesting that hemp has antibacterial characteristics due to the presence of lignin. In the Comparison washed samples with unwashed ones, there were more kinds of fungi in washed samples. In the cellulase activity test, Acremonium kiliense had the highest level cellulase activity, suggesting that Acremonium killiense has an important Influence on damage of textiles.

• 한국균학회지
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• 제35권1호
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• pp.11-27
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• 2007

2004년 4월부터 2006년 11월까지 내장산 국립공원 고등균류를 조사한 결과는 다음과 같다. 조사기간 동안 고등균류는 총 5강 19목 60과 168속 418종(미기록종 10과 13속 15종 포함)이 조사 되었으며, 담자균아문은 47과 143속 384종이, 자낭균아문은 9과 19속 28종이었으며 점균문은 4과 6속 6종이 조사되었으며, 담자균아문의 모균아강(Hymenomycetidae)이 34과 122속 353종으로 대부분을 차지하였다. 가장 많이 발생된 균류는 송이버섯과로 64종이었으며, 무당버섯과(39종), 구멍장이버섯과(36종), 그물버섯과(36종) 순으로 나타났다. 고등균류 버섯 발생은 강수량 및 대기온도가 높은 시기인 기후 환경요인과 밀접한 관계가 있는 7월, 8월 및 9월에 집중하였다. 고등균류 버섯 분포에 영향을 기후환경 요인은 강수량, 상대습도 및 대기온도가 중요한 인자로 나타났다.

• 한국작물학회지
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• 제28권2호
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• pp.262-266
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• 1983

인삼종자의 내과피에 부생하는 진균이 배생장 및 개압에 미치는 영향을 알기 위하여 종자와 층적장의 모래를 살균 처리한 뒤 종자를 층적하여 얻은 결과를 요약하면 다음과 같다. 1. 종자소독에 의해 종자의 내과피에 부생하는 균밀도가 현저히 저하되었으며 종자의 경도변화가 크게 억제되었고, 종자의 경도와 균밀도간에는 부(-)상관 $(r=0.984^**)$이 인정되었다. 2. 종자내 수분함량의 증가는 종자소독구가 대조구보다 20일 늦게 시작되었다. 3. 배생장과 개압은 종자소독에 의해 크게 억제되었고 종자의 경도가 낮을수록 배생장은 잘되었다. 인삼종자의 내과피에 부생하는 진균이 내과피를 경화시켜 산소, 수분 등의 공급을 쉽게 함으로써 배생장 및 개갑을 촉진시키는 것으로 생각된다.

• The Plant Pathology Journal
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• 제36권3호
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• pp.193-203
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• 2020

Volatile compounds (VOCs) are not only media for communication within a species but also effective tools for sender to manipulate behavior and physiology of receiver species. Although the influence of VOCs on the interactions among organisms is evident, types of VOCs and specific mechanisms through which VOCs work during such interactions are only beginning to become clear. Here, we review the fungal volatile compounds (FVOCs) and their impacts on different recipient organisms from perspective of distinct lifestyles of the filamentous fungi. Particularly, we discuss the possibility that different lifestyles are intimately associated with an ability to produce a repertoire of FVOCs in fungi. The FVOCs discussed here have been identified and analyzed as relevant signals under a range of experimental settings. However, mechanistic insight into how specific interactions are mediated by such FVOCs at the molecular levels, amidst complex community of microbes and plants, requires further testing. Experimental designs and advanced technologies that attempt to address this question will facilitate our understanding and applications of FVOCs to agriculture and ecosystem management.