• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.214-219
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• 2007

A $3{\times}3$ factorial design experiment was conducted to investigate the effect of temperature and duration of storage on the fermentation quality of potato pulp ensiled with two fungal inoculants under laboratory conditions. The inoculants, Rhizopus oryzae (R) and Amylomyces rouxii (A) were each added to potato pulp material to contain at least $1{\times}10^6$ CFU/g fresh matter, and silages without additives served as controls. The silages were stored under three temperature regimes; 4, 12 and $25^{\circ}C$. Three silos per treatment from every temperature regime were opened on days 7, 24 and 40 days after ensiling to investigate treatment effects on fermentation quality, starch and sugar concentrations. Increase in temperature and duration of storage had a positive significant effect (p<0.01) on the fermentation quality of potato pulp silage (PPS). The inoculants had little effect (p>0.05) on the fermentation quality of the silages. Sugar concentration in the silages decreased with increase in temperature (p<0.01) but increased (p<0.05) with progression of duration of storage. The fungal inoculants had no effect on starch degradation in PPS. The results suggest that storage temperature and duration of storage are more important in determining the rate of fermentation than addition of the fungal inoculants in PPS.

• Mycobiology
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• 제44권3호
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• pp.162-170
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• 2016

In this paper, we demonstrate the ability of Arabidopsis thaliana to detect different mixtures of volatile organic compounds (VOCs) emitted by the common indoor fungus, Aspergillus versicolor, and demonstrate the potential usage of the plant as a bioindicator to monitor fungal VOCs in indoor air. We evaluated the volatile production of Aspergillus versicolor strains SRRC 108 (NRRL 3449) and SRRC 2559 (ATCC 32662) grown on nutrient rich fungal medium, and grown under conditions to mimic the substrate encountered in the built environment where fungi would typically grow indoors (moist wallboard and ceiling tiles). Using headspace solid phase microextraction/gas chromatography-mass spectrometry, we analyzed VOC profiles of the two strains. The most abundant compound produced by both strains on all three media was 1-octen-3-ol. Strain SRRC 2559 made several terpenes not detected from strain SRRC 108. Using a split-plate bioassay, we grew Arabidopsis thaliana in a shared atmosphere with VOCs from the two strains of Aspergillus versicolor grown on yeast extract sucrose medium. The VOCs emitted by SRRC 2559 had an adverse impact on seed germination and plant growth. Chemical standards of individual VOCs from the Aspergillus versicolor mixture (2-methyl-1-butanol, 3-methyl-1-butanol, 1-octen-3-ol, limonene, and ${\beta}-farnesene$), and ${\beta}-caryophyllene$ were tested one by one in seed germination and vegetative plant growth assays. The most inhibitory compound to both seed germination and plant growth was 1-octen-3-ol. Our data suggest that Arabidopsis is a useful model for monitoring indoor air quality as it is sensitive to naturally emitted fungal volatile mixtures as well as to chemical standards of individual compounds, and it exhibits relatively quick concentration- and duration-dependent responses.

• The Plant Pathology Journal
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• 제35권5호
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• pp.437-444
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• 2019

Chlorine dioxide ($ClO_2$) has been widely used as an effective disinfectant to control fungal contamination during postharvest crop storage. In this study, Fusarium oxysporum f. sp. batatas SP-f6 from the black rot symptom of sweetpotato was isolated and identified using phylogenetic analysis of elongation factor 1-${\alpha}$ gene; we further examined the in vitro and in vivo inhibitory activities of $ClO_2$ gas against the fungus. In the in vitro medium tests, fungal population was significantly inhibited upon increasing the concentration and exposure time. In in vivo tests, spore suspensions were drop-inoculated onto sweetpotato slices, followed by treatment using various $ClO_2$ concentrations and treatment times to assess fungus-induced disease development in the slices. Lesion diameters decreased at the tested $ClO_2$ concentrations over time. When sweetpotato roots were dip-inoculated in spore suspensions prior to treatment with 20 and 40 ppm of $ClO_2$ for 0-60 min, fungal populations significantly decreased at the tested concentrations for 30-60 min. Taken together, these results showed that $ClO_2$ gas can effectively inhibit fungal growth and disease development caused by F. oxysporum f. sp. batatas on sweetpotato. Therefore, $ClO_2$ gas may be used as a sanitizer to control this fungus during postharvest storage of sweetpotato.

• Journal of the Korean Wood Science and Technology
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• 제51권3호
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• pp.183-196
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• 2023

Recently, the morphological and molecular features of five stain fungi infecting rubberwood (Hevea brasiliensis), namely Paecilomyces maximus, Paecilomyces formosus, Penicillium crustosum, Paecilomyces lecythidis and Aspergillus chevalieri, have been studied. Prior to this study, the authors revealed that catechin from gambir (Uncaria gambir) could inhibit the growth of the white-rot fungus Schizophyllum commune, and it was important to determine the bioactivity of the aforementioned agent against A. chevalieri. The efficacy of the biocidal agent was examined using a laboratory wooden block test. Rubberwood blocks, 8 mm in thickness, 20 mm in width, and 30 mm in length, were impregnated with catechin solution at concentrations of 6%, 9%, 12%, and 15% (w/v) using the vacuum-pressure method, and their bioactivity was monitored over three weeks through visual and scanning electron microscope assessment of fungal growth as well as the discoloration intensity of the wood samples. The results showed that catechin treatment increased the resistance of wood samples to A. chevalieri. Overall, the higher the catechin concentration, the lower the fungal growth. The lowest fungal growth was observed in the wood samples treated with 12% and 15% catechin (score of 0), demonstrating no discoloration. In contrast, the fungal growth score of the untreated wood samples reached 4, indicating severe discoloration. Catechins appear to be adequate biofungicides against stain fungi in rubberwood.

• 한국균학회지
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• 제20권2호
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• pp.109-117
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• 1992

운동성을 띠는 5가지 부생균과 1종류의 식물병원세균으로 Agrobacterium radiobacter, Bacillus subtilis, B. polymyxa, Pseudomonas aeruginosa, P. fluorescens 및 Xanthomonas malvacearum을 공시하여 이들 세균이 Cochliobolus sativus 분생포자, Fusarium oxysporum f. sp. ciceri의 후막포자, Macrophomina phaseolina의 균핵 및 Phytophthora drechsleri f. sp. cajani 난포자의 분비물에 미치는 화학주성을 서로 다른 무생물적 조건하에서 실험하였다. 균의 분비물의 농도와 세균세포의 끌리는 유인사이에는 정상관$(r=0.76{\sim}0.89)$이 있었다. 유사한 결과로서 화학주성반응과 배양간격에서도 통계적인 정상관이 있다$(r=0.82{\sim}0.95)$. 세균의 화학주성반응은 온도와 pH에 크게 영향을 받는다. 최적 화학주성을 나타내는 온도로서 A. radiobacter는 $25^{\circ}C$, B. polymyxa, P. aerugionosa, p. fluorescens and X. madracearum은 $30^{\circ}C$이었고, B. subtilis는 $35^{\circ}C$가 최적이었다. 최대 화학주성을 나타내는 분비물의 주성은 pH7이고 pH3과 11에서는 buffer와 같았다. 시험용 모세관에 유인물질이나 buffer 중 어느 종류가 채워져도 유인물질이 있는 시험관에 연결되면 세균은 주성이 나타난다는 것이 증명되었다.

• Journal of Microbiology and Biotechnology
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• 제28권1호
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• pp.145-156
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• 2018

Most eukaryotic peroxiredoxins (Prxs) are readily inactivated by a high concentration of hydrogen peroxide ($H_2O_2$) during catalysis owing to their "GGLG" and "YF" motifs. However, such oxidative stress sensitive motifs were not found in the previously identified filamentous fungal Prxs. Additionally, the information on filamentous fungal Prxs is limited and fragmentary. Herein, we cloned and gained insight into Aspergillus nidulans Prx (An.PrxA) in the aspects of protein properties, catalysis characteristics, and especially $H_2O_2$ tolerability. Our results indicated that An.PrxA belongs to the newly defined family of typical 2-Cys Prxs with a marked characteristic that the "resolving" cysteine ($C_R$) is invertedly located preceding the "peroxidatic" cysteine ($C_P$) in amino acid sequences. The inverted arrangement of $C_R$ and $C_P$ can only be found among some yeast, bacterial, and filamentous fungal deduced Prxs. The most surprising characteristic of An.PrxA is its extraordinary ability to resist inactivation by extremely high concentrations of $H_2O_2$, even that approaching 600 mM. By screening the $H_2O_2$-inactivation effects on the components of Prx systems, including Trx, Trx reductase (TrxR), and Prx, we ultimately determined that it is the robust filamentous fungal TrxR rather than Trx and Prx that is responsible for the extreme $H_2O_2$ tolerence of the An.PrxA system. This is the first investigation on the effect of the electron donor partner in the $H_2O_2$ tolerability of the Prx system.

• 한국식물병리학회지
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• 제1권2호
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• pp.128-135
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• 1985

국내 사과산지 4개처에서 푸른곰팡이 병균 Penicillium expansum을 분리하여 각종 살균제에 대한 반응을 조사하였다. 일반적으로 균의 약제내성은 지역간에 차이가 적었으며 약제의 종류 및 농도에 의한 차이는 컸고 봄균주가 자랄 수 없는 고농도에서도 가을균주는 생장하였다. 균사생장에 대한 살균제의 $ED_{50}$ 및 $0.1{\mu}g\~41.7{\mu}g/ml$ 및 $100{\mu}g\~2,250{\mu}g/ml$로서 저장고 및 과수원에서 분리한 균의 억제효과가 높고 균의 내성이 낮았으며, captafol, captan, iprodione, mancozeb이 $2.6{\mu}g\~750{\mu}g/ml$ 및 $638{\mu}g\~40,500{\mu}g/ml$로서 약효 및 균의 내성이 중도였고, chlorothalonil folpet, oxidong, propineb, triademefon이 $27.8{\mu}g\~8,354{\mu}g/ml$ 및 $2,625{\mu}g\~150,357{\mu}g/ml$로서 효과가 낮고 균의 내성이 높았다. 포자형성 억제효과는 균사생장 억제효과와 같은 경향을 보였으며 포자발아 억제효과는 ployoxin 및 triademefon을 제외하고는 반대의 경향을 보였다.

• 한국응용곤충학회지
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• 제24권1호
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• pp.19-24
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• 1985

국내(國內) 주요(主要) 사과산지(産地) 4개처(個處)에서 저장중(貯藏中) 부패과(腐敗果) 및 수확전(收穫前) 과수원(果樹園) 이병과(罹病果)에서 Alternaria mali를 분리(分離)하여 각종(各種) 살균제(殺菌劑)를 가용(加用)한 PSA배지상(培地上)에 배양(培養)하여 균(菌)의 내성(耐性)을 조사(調査)한 결과(結果)는 다음과 같다. 지역별(地域別) 및 계절별(季節別) 균주간(菌株間)에는 약제내성(藥劑耐性) 차이(差異)가 적었으며, 살균제(殺菌劑)의 종류(種類) 및 농도(濃度)에 따른 차이(差異)는 컸다. Chlorothalonil 및 captafol의 균생육(菌生育)에 대(對)한 MIC 는 각각(各各) 100,238 및 $81,000{\mu}g/ml$ 이상(以上)으로서 효과(效果)가 가장 낮았으며 균(菌)의 내성(耐性)이 가장 높았다. lprodione 및 folpet의 MIC는 각각(各各) 3,825 및 $3,000{\mu}g/ml$ 이상(以上)으로 중도(中度)의 효과(效果)를 보였으며 균(菌)의 내성(耐性)도 중도(中度)였다. polyoxin의 MIC는 $900{\mu}g/ml$로서 효과(效果)가 높았으나 이는 권장농도(勸奬濃度)의 9배(倍)로서 균(菌)의 내성(耐性)이 약간(若干) 발생(發生)한 경향(傾向)을 보였다. polydong 및 oxidong 의 MIC 는 각각(各各) 500 및 $1,000{\mu}g/ml$ 이하(以下)로서 효과(效果)가 가장 높았으며 권장농도(勸奬濃度) 이하(以下)에서 균생육(菌生育)을 억제(抑制)하였으므로 현재(現在)로서는 농가(農家) 과수원(果樹園)에서 균(菌)의 내성(耐性)이 가장 낮았다. 공시(供試) 살균제(殺菌劑) 7종(種)에 대(對)한 사과 반점(斑點) 낙엽병균(落葉病菌)의 균사생장(菌絲生長), 포자형성(胞子形成) 및 포자발아(胞子發芽)는 같은 경향(傾向)의 반응(反應)을 보였다.

• 한국산업보건학회지
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• 제28권4호
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• pp.382-392
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• 2018

Objective: Allergic diseases such as asthma due to fungal exposure in houses have increased, and proper management is urgent. Mold can grow in the air, floor, walls, and other areas according to environmental conditions, and there are many limitations to the conventional methodology for examining fungal exposure. For this reason, the degree of fungal contamination is being evaluated by ERMI (Environmental Relative Moldiness Index), a quantitative analysis method proposed by the EPA. In this study, we compared ERMI values between water-damaged dwellings and non-damaged ones to evaluate the effectiveness of Korean ERMI values. We also explored the association of ERMI values with the level of airborne mold and characteristics of dwellings. Methods: Floor dust was collected after installing a Dustream collector on the suction port of a vacuum cleaner. The collected samples were filtered to remove only 5 mg of dust, and DNA was extracted using the FastDNA SPIN KIT protocol. Results: The ERMI values were found to be 19.6 (-6.9-58.8) for flooded houses, 7.5 (-29.2-48.3) for leaks/condensation, and 0.8 (-29.2-37.9) for non-damaged dwellings. The airborne concentration of mold for flooded, leakage or condensed, and non-damaged houses were $684CFU/m^3$, $566CFU/m^3$, and $378CFU/m^3$, respectively. The correlation between ERMI values and the levels of airborne mold was low (R = 0.038), but a weakly significant association of the ERMI values with the concentration of particulate matter ($PM_{10}$) was observed as well(R=0.231,P<0.05). Conclusions: Our findings show that the reference value using ERMI can be used to distinguish water-damaged and non-damaged dwellings. It is believed that ERMI values could be a promising tool for assessing long-term fungal exposure in dwellings.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.691-694
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• 2007

Acetic acid and butyric acid were produced by the anaerobic fermentation of soil mixed with wheat or rice bran. The concentration of acetic acid produced in the wheat and rice bran-treated soil was 31.2mM and 8mM, respectively, whereas the concentration of butyric acid in the wheat and rice bran-treated soil was 25.0mM and 8mM, respectively. The minimal fungicidal concentration (MFC) for all the fungal strains was 40-60mM acetic acid, 20-40mM butyric acid, and 40-60mM mixture of acetic acid: butyric acid (1:1, v/v). Consequently, the efficacy of mixing wheat-bran with soil to control soil diseases was demonstrated.