• Journal of Microbiology and Biotechnology
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• 제29권1호
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• pp.105-113
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• 2019

Although siderophore compounds are mainly biosynthesized as a response to iron deficiency in the environment, they also bind with other metals. A few studies have been conducted on the impact of heavy metals on the siderophore-mediated iron uptake by microbiome. Here, we investigated siderophore production by a variety of rhizosphere fungi under different concentrations of $Zn^{2+}$ ion. These strains were specifically isolated from the rhizosphere of Panax ginseng (Korean ginseng). The siderophore production of isolated fungi was investigated with chrome azurol S (CAS) assay liquid media amended with different concentrations of $Zn^{2+}$ (50 to $250{\mu}g/ml$). The percentage of siderophore units was quantified using the ultra-violet (UV) irradiation method. The results indicated that high concentrations of $Zn^{2+}$ ion increase the production of siderophore in iron-limited cultures. Maximum siderophore production by the fungal strains was detected at $Zn^{2+}$ ion concentration of $150{\mu}g/ml$ except for Mortierella sp., which had the highest siderophore production at $200{\mu}g/ml$. One potent siderophore-producing strain (Penicillium sp. JJHO) was strongly influenced by the presence of $Zn^{2+}$ ions and showed high identity to P. commune (100% using 18S-rRNA sequencing). The purified siderophores of the Penicillium sp. JJHO strain were chemically identified using UV, Fourier-transform infrared spectroscopy (FTIR), and matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF-MS) spectra.

• 현장농수산연구지
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• 제14권1호
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• pp.61-83
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• 2012

곤포사일리지에 발생하는 곰팡이를 분류 동정하기 위하여 2009년부터 2011년까지 253개의 오염된 곤포사일리지를 채집하였다. 이탈리안라이그라스 수단 그라스, 호밀, 옥수수, 보리와 귀리에서 분리한 총 253 목초 샘플을 분석했다. 채집된 곤포사일리지에서 총 270균주를 순수 분리하였고, 분리된 곰팡이의 형태와 rDNA sequence를 분석하여 분류 동정하였다. 분리한 곰팡이를 형태를 기준으로 분류 동정 한 결과 Rhizopus sp., Fusarium spp., Coprinus sp., Blastomyces sp., Aureobasidium sp., Polypaecilum sp., Botryoderma sp., Mucor sp., Scytalidium sp., Sphaeropsis sp., Aspergillus spp., Trichocladium sp., Humicola sp., Staphylotrichum sp., Periconia sp., Verticillium sp., Diplococcium sp., Penicillium spp., Trichoderma spp. 등 19종의 곰팡이가 분리 동정되었다. 한편, 사일리지에서 분리한 곰팡이의 염기서열을 분석한 결과 Acremonium strictum, Asperillus tubingensis, Bionectria ochroleuca Dipodascaceae sp., Fusarium proliferatum, Fusarium oxysporum, Fusrium solani, Gelasinospora reticulata, Gibberella monliliformis, Gibberella zeae, Nectria mauritiicola, Penicillium paneum, Pseudallecheria boydii, Schizaphyllum commune, Scoplariopsis brevicaulis, SimpliciIlium lamellicola로 분류 동정되었다. PenicIlliwn sp.와 Trichoderma sp.는 각각 74와 64균주가 분리되어 가장 많이 분리 동정되었고, Humicola sp., Aspergillus sp., Coprinus sp., Fusarium spp.도 10~30 균주가 분리 동정되었다. 곤포 사일리지에서의 대부분의 곰팡이는 한 종 이상의 곰팡이가 복합적으로 오염되었다.

• Mycobiology
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• 제47권4호
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• pp.430-440
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• 2019

Fungal contamination of built-in furniture is a frequent problem in Korea when new apartment is built. However, domestic information on the contaminating fungi is very limited. This study was conducted to isolate, identify and characterize the fungi of the problem in one of the apartment houses where the fungi were claimed in the built-in furniture before the house owner moves in. Fungi present in the furniture installed in a main room, dress room, and kitchen side were visually and microscopically confirmed and purely isolated on PDA. The isolated fungi were identified by analyzing the morphological characteristics and nucleotide sequence of the ITS, calmodulin gene, and TEF-1α gene. Aspergillus creber, A. niger, A. pseudoglacus, A. ruber, Cladosporium perangustum and Penicillium commune were identified. Four out of the six fungal species were positive for at least one enzyme in six kinds of extracellular enzyme assays. When these four species (A. creber, A. niger, C. perangustum and P. commune) were inoculated onto four kinds of wood chips of furniture materials, they were able to colonize all of the wood chips. Their settlement was better at 95% humidity condition than at 30% humidity condition. Among the four species, C. perangustum caused the darkest discoloration and secreted the most number of extracellular enzymes. The four species were re-isolated from the colonized wood chips and confirmed as the problematic fungi in the built-in furniture.

• Mycobiology
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• 제33권4호
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• pp.210-214
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• 2005

More than 120 isolates of lactic acid bacteria obtained from Kimchi was screened for antifungal activity against Aspergillus fumigatus. Approximately 10% of the isolates showed inhibitory activity and only 4.16% (five isolates) exhibited strong activity against the indicator fungus A. fumigatus. The five isolates showed a wide rang of antifungal activity against A. flavus, Fusarium moniliforme, Penicillium commune, and Rhizopus oryzae. They were identified by 16S rDNA sequencing as Lactobacillus cruvatus, L. lactis subsp. lactis, L. casei, L. pentosus, and L. sakei. The effect of Lactobacillus on mycelial growth and fungal biomass as well as its ability to produce toxic compounds were determined. The results indicate that the three species, Lactobacillus casei, L. lactis subsp. lactis, and L. pentosus, are active against A. fumigatus.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.426-429
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• 2004

Eleven fungal strains previously isolated from the Mexican desert were evaluated for their capacity to use catechin as carbon source in submerged cultures. At 2 g/l of catechin, all strains grew better than the control strains, Aspergillus niger Aa-20. Aspergillus niger PSH and Penicillium commune EH2 degraded 79.33％ and 76.35％ with degradation rates of 0.0065 and 0.0074 g/l/h, respectively, when an initial catechin concentration of 3 g/l was used. Obtained results demonstrated the potential biotechnological capacity of these fungal strains to use condensed tannins as carbon source.

• Mycobiology
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• 제43권3호
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• pp.258-265
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• 2015

The fungi on Meju are known to play an important role as degrader of macromolecule of soybeans. In order to elucidate the origin of fungi on traditional Meju, mycobiota of the air both inside and outside traditional Meju fermentation rooms was examined. From 11 samples of air collected from inside and outside of 7 Meju fermentation rooms, 37 genera and 90 species of fungi were identified. In outside air of the fermentation room, Cladosporium sp. and Cladosporium cladosporioides were the dominant species, followed by Cladosporium tenuissimum, Eurotium sp., Phoma sp., Sistotrema brinkmannii, Alternaria sp., Aspergillus fumigatus, Schizophyllum commune, and Penicillium glabrum. In inside air of the fermentation room, Cladosporium sp., Aspergillus oryzae, Penicillium chrysogenum, Asp. nidulans, Aspergillus sp., Cla. cladosporioides, Eurotium sp., Penicillium sp., Cla. tenuissimum, Asp. niger, Eur. herbariorum, Asp. sydowii, and Eur. repens were collected with high frequency. The concentrations of the genera Aspergillus, Eurotium, and Penicillium were significantly higher in inside air than outside air. From this result and those of previous reports, the origin of fungi present on Meju was inferred. Of the dominant fungal species present on Meju, Lichtheimia ramosa, Mucor circinelloides, Mucor racemosus, and Scopulariopsis brevicaulis are thought to be originated from outside air, because these species are not or are rarely isolated from rice straw and soybean; however, they were detected outside air of fermentation room and are species commonly found in indoor environments. However, Asp. oryzae, Pen. polonicum, Eur. repens, Pen. solitum, and Eur. chevalieri, which are frequently found on Meju, are common in rice straw and could be transferred from rice straw to Meju. The fungi grow and produce abundant spores during Meju fermentation, and after the spores accumulate in the air of fermentation room, they could influence mycobiota of Meju fermentation in the following year. This could explain why concentrations of the genera Aspergillus, Eurotium, and Penicillium are much higher inside than outside of the fermentation rooms.

• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.22-28
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• 2005

Gibberellins (GAs) play important roles in plant growth and development. Fifty-four fungi were isolated from the roots of 4 kinds of Sesamum indicum plants, and the production of GAs was spectrophotometrically examined. The number of GA-producing fungi was two strains from S. indicum, four strains from Gold S. indicum, and five strains from Brown S. indicum. Eleven fungi with GAs-producing activity were incubated for seven days in 40 ml of Czapek's liquid medium at $25^{\circ}C$ and 120 rpm, and the amount of each GA in the medium was measured by gas chromatographymass spectrometery (GC-MS). Penicillium commune KNU5379 produced more $GA_3$, $GA_4$, and $GA_7$ than Gibberella fujikuroi, Fusarium proliferatum, and Neurospora crassa which are known as GAs-producing fungi. GAs-producing activity of the P. commune KNU5379 was shown to produce 71.69 ng of $GA_1$, 252.42 ng of $GA_3$, 612.00 ng of $GA_4$, 259.00 ng of $GA_7$, and 202.69 ng of $GA_9$ in 25 ml of liquid medium. Bioassay of culture fluid of GA-producing fungi was also performed on rice sprout.

• 한국식품과학회지
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• 제28권2호
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• pp.366-370
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• 1996

흥삼분말의 위생적 살균을 위해 감마선 조사기법을 이용하였다. 감마선조사에 따른 오염 미생물의 살균효과는 호기성 전세균은 7.5 kGy, 곰팡이 및 대장균군은 2.5 kGy의 조사선량으로 검출한계 이하로 제거시킬 수 있었고 실온에서 6개월 저장후에도 미생물의 생육과 증식은 없었다. 홍삼분말에서 분리, 동정된 곰팡이는 Penicillium commune, Aspergillus niger, Aspergillus versicolor, Aspergillus unguis로 이들 포자의 $D_{10}$값은 각각 0.37-0.5 kGy. 0.24-0.31 kGy, 0.25-0.36 kGy, 0.28-0.41 kGy였으며, 2.5 kGy 선량에서의 불활성화계수는 각각 5-6.5, 7.4-9.3, 6.5·.9.1, 6.1-8.4이었다. 한편 홍삼 extract를 첨가한 배지가 PDA 배지보다 더 낮은 방사선 감수성을 보였고, 분리곰팡이의 배지특성에 따른 생육양상은 배양중기 이후부터 흥삼 extract 배지상에서 생육이 왕성하였다.

• 한국식생활문화학회지
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• 제37권5호
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• pp.446-453
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• 2022

In this study, we analyzed the antifungal activities of five essential oils (clove, rosemary, thyme, basil, and oregano) against three fungi (Penicillium oxalicum, Penicillium commune, and Cladosporium cladosporioides) isolated from farm-type fermented meat products Though their antifungal activities differed for each fungus, thyme had the greatest effect. Notably, C. cladosporioides showed the highest sensitivity to essential oils, and growth inhibitory effects were greater than for the other two strains. Additionally, ABTS, DPPH, and FRAP analysis confirmed that the five essential oils studied had antioxidant activity. ABTS analysis showed that clove (75%) and oregano (75%) oils had the highest antioxidant activities (both 93.7%). DPPH analysis showed that clove (75%) and rosemary (75%) oils had significantly greater antioxidant activities (both 93.8%) than thyme, basil, or oregano oils. FRAP results indicated that clove and basil oils were the strongest reductants. Comprehensive comparative analysis indicated that clove oil had more antioxidant activity than the other four essential oils. Overall, the study shows that the excellent antifungal properties of clove oil could be harnessed to produce safe fermented meat products by preventing rancidity and mold contamination.

• Journal of Animal Science and Technology
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• 제64권2호
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• pp.343-352
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• 2022

Pig slaughterhouses harbor high humidity because of the necessary cleaning that takes place simultaneously with slaughter, which facilitates the existence of mold. Due to the enclosed space, there are several limitations to the control of mold growth with respect to cleaning, ventilation, and drying. In this study, the prevalence of fungi was investigated in four pig slaughterhouses in Korea. Four fungi (Aspergillus niger, Penicillium commune, Penicillium oxalicum, and Cladosporium cladosporioides) were detected with the highest frequency. These four strains were subjected to various treatments to reduce their growth. The fungi were inoculated onto stainless steel (SS) chips and treated with ultraviolet (UV)-C irradiation and hot water. Individual treatments with UV-C (15, 30, 90, 150, 300, and 600 mJ/cm²), and hot water (60, 65, 70, and 83℃) were performed to sanitize the SS chips. Simultaneous cleaning with 60℃ hot water and more than 150 mJ/cm² of UV-C reduced the fungal incidence by > 6.5 Log from 6.6-7.0 Log CFU/cm² (initial count). Our results demonstrate that a combined treatment of UV-C and hot water is the most economical and convenient way to prevent microbiological contamination of small tools (such as knives and sharpeners) and steel surfaces in slaughterhouses.