• 한국미생물·생명공학회지
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• 제23권6호
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• pp.737-746
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• 1995

Through the study of identification of filamentous molds isolated from 12 traditional Nuruk, collected from several regions in Korea, 78 strains of Absidia spp., including Absidia corymbifera, Absidia ramosa, and Absidia sp. of which specific names were not identified, 19 strains of Rhizopus spp. including Rhizopus cohnii, Rhizopus arrhizus, and Rhizopus oryzae, 8 strains of Circinella spp., 1 strain of Actinomucor sp., 49 strains of Aspergillus spp., including Aspergillus oryzae, Aspergillus flavus, Aspergillus flavus var. columnaris, Aspergillus wentii, Aspergillus candidus, Aspergillus fumigatus, Aspergillus niger, and Aspergillus foetidus, 2 strains of Cladospoyium spp. and 2 strains Botryotrichum spp., etc. total 159 kinds of filamentous molds were isolated and identified. There were many differences in numbers and distributions of filamentous molds from each Nuruk according to their collected region. Absidia spp. were most frequently isolated from every Nuruk sample. Aspergillus oryzae, Aspergillus candidus, and Rhizopus cohnii showed even distribution. Penicillium sp. and Mucor sp. were not detected. Actinomucor sp., Aspergillus foetidus, Botryotrichum sp., and Cladosporium spp., which have not been reported by far, were found. Amylase activities, pH stability of amylase, and acid productivity of isolated strains were compared.

• 한국미생물·생명공학회지
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• 제24권5호
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• pp.574-578
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• 1996

In the course of screening for the antifungal compounds against Candida albicans, an antifungal compound (F1480) was isolated from the culture broth of Aspergillus candidus F1484. Isolation and purification of compound F1484 were performed using ethyl acetate extraction, silica gel column chromatography, ODS column chromatography, and preparative HPLC. The structure of compound F1484 was determined by the spectroscopic analyses of EI-MS, $^{13}$C, $^{1}$H-NMR, DEPT, HMQC, and HMBC. This compound appeared to have a structure of antifungal agent, chloroflavonin. In addition to antifungal activities against the yeast phase of Candida species, compound F1484 showed cytotoxic effect against various human tumor cell lines.

• The Plant Pathology Journal
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• 제26권2호
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• pp.121-129
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• 2010

We evaluated microbial populations and aflatoxin production in unhulled and white rice from rice processing complexes of the National Agricultural Cooperative Federation in five regions in Korea and identified three predominant Aspergillus species. Fungal and bacterial populations in rice samples were significantly different between regions in 2007. Aflatoxins were also detected and varied at the levels of 2.45 - 3.43 ng per g unhulled rice grain and 1.29 - 2.09 ng per g white rice grain. Unhulled rice generally detected higher level of aflatoxins than white rice regardless of sampling regions; however, no significant differences were found in Anseong and Cheonan in 2005 and Cheonan and Gimpo in 2007. Aflatoxin production between sampling regions was not different regardless of rice type and sampling year. Although the fungal diversity was highly distinct from region to region, three Aspergillus isolates were predominant in the rice samples; thus, representative isolates AC317, AF57, and AF8 were selected and identified based on their morphological and molecular characteristics. Consequently, isolates AC317, AF57, and AF8 were identified as A. candidus, A. flavus, and A. fumigatus, respectively. These fungi can produce mycotoxins that are harmful for consumers and thus it is important to detect and reduce the population of storage fungi in rice.

• The Plant Pathology Journal
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• 제24권1호
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• pp.74-79
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• 2008

This research was conducted to evaluate fungal and bacterial populations in unhulled and brown rice under indoor storage conditions, and to examine the relationship between microbial populations and environmental conditions such as temperature and relative humidity. The temperature and relative humidity of the storage room ranged from $22.6^{\circ}C\;to\;27.0^{\circ}C$ and 23.3% to 44.2%, respectively. Total fungal and bacterial populations remained relatively stable over the storage period. Predominant fungi included Aspergillus candidus, A. flavus, A. fumigatus, and Penicillium spp.; the predominant bacteria were Bacillus, Microbacterium, Sphingomonas, and Methylobacterium spp. Total fungi and bacteria were not significantly correlated with either unhulled (r=0.448, P=0.372) or brown (r=0.466, P=0.351) rice. In unhulled rice, total fungi showed positive correlations with total Aspergillus (r=0.994, P<0.001) and total Penicillium (r=0.906, P<0.05); A. flavus was positively correlated with total Aspergillus (r=0.913, P<0.05) and total fungi (r=0.868, P<0.05). In brown rice, Bacillus spp. was also positively correlated with total bacteria (r=0.998, P<0.001). Mean temperature was negatively correlated with A. candidus (r=-0.852, P<0.05) and total fungi (r=-0.961, P<0.01), and mean relative humidity was positively correlated with total Penicillium spp.(r=0.884, P<0.05) in brown rice. Hence these results could provide basic information on the fungal and bacterial populations in unhulled and brown rice stored under room conditions, and on the effect of environmental conditions on the populations of fungi and bacteria, especially Aspergillus and Penicillium spp.

• 한국응용곤충학회지
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• 제42권4호
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• pp.329-334
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• 2003

쌀바구미와 저장 곡물 곰팡이간의 상호작용 분석의 일환으로 곰팡이 종에 대한 쌀바구미의 분포 선호성을 조사하였다. 쌀바구미는 비교 대상 4종 곰팡이(Aspergillus candidus, A. niger, A. flavus와 Penicillium spp.)에 오염된 현미를 살균된 현미보다 선호하였으며, 선호도는 A. candidus와 Penicillium spp.에 대해서 가장 높았다. 차대 쌀바구미 우화수는 A. candidus와 Penicillium 오염미에서 가장 많았으며 A. flavus 오염미에서 가장 적었다. 쌀바구미의 곰팡이 오염미에 대한 선호와 쌀바구미 적합도간 불일치 현상은 쌀바구미의 분포 및 곡물 곰팡이 선호도가 알려진바 유사 니체에서의 장기적인 공진화 과정을 거쳐 이루어진 종간 상호작용의 조정과 아울러 영양적 특성 등 단기적 서식환경의 적절성의 두 가지 측면에서 설명될 수 있음을 암시하는 것으로 생각된다.

• Mycobiology
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• 제46권3호
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• pp.287-295
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• 2018

In this study, we evaluated the effect of different temperatures (10, 20, 30, and $40^{\circ}C$) and relative humidities (RHs; 12, 44, 76, and 98%) on populations of predominant grain fungi (Aspergillus candidus, Aspergillus flavus, Aspergillus fumigatus, Penicillium fellutanum, and Penicillium islandicum) and the biocontrol activity of Pseudomonas protegens AS15 against aflatoxigenic A. flavus KCCM 60330 in stored rice. Populations of all the tested fungi in inoculated rice grains were significantly enhanced by both increased temperature and RH. Multiple linear regression analysis revealed that one unit increase of temperature resulted in greater effects than that of RH on fungal populations. When rice grains were treated with P. protegens AS15 prior to inoculation with A. flavus KCCM 60330, fungal populations and aflatoxin production in the inoculated grains were significantly reduced compared with the grains untreated with strain AS15 regardless of temperature and RH (except 12% RH for fungal population). In addition, bacterial populations in grains were significantly enhanced with increasing temperature and RH, regardless of bacterial treatment. Higher bacterial populations were detected in biocontrol strain-treated grains than in untreated control grains. To our knowledge, this is the first report showing consistent biocontrol activity of P. protegens against A. flavus population and aflatoxin production in stored rice grains under various environmental conditions of temperature and RH.

• 한국응용곤충학회지
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• 제13권2호
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• pp.71-75
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• 1974

1. 쌀바구미류는 성충>유충>용의 순으로 체내에 곰팡이를 많이 갖고 있었다. 2. 무균소맥에서 사육하면서 체내 균류의 잔존상황을 조사한 바 10일후에는 완전히 제거할 수 있었고, 가장 오래 잔류하는 것은 A. candidus였다. 3. 곰팡이류의 산난수에 미치는 영향은 A. candidus 구가 가장 많았고 A. ruber 그리고 대조구의 순이고 A. niger구가 가장 적었다. 4. 유충의 생육은 A. candidus>A. ruber>대조구의 순으로 양호하였고 A. niger구에서는 2-3령까지 밖에 발육을 하지 못하였다. 5. 생육이 가장 빠른 것은 A. candidus구로 제3주에용화개체를 볼 수 있었고 제4편에 성충 우화를 볼 수 있었다. 대조구에서도 동일한 경향을 볼 수 있었으나 생육은 약간 늦었다. 6. A. niger구에서 생육이 불량한 것은 왕성한 균생장으로 쌀바구미의 활동이 저해되는 것과 동시에 불명의 원인이 있는 듯 하였다. 7. 저곡중의 쌀바구미와 곰팡이류간에는 진화과정을 통하여 원시적 협동작용이 있었다.

• Mycobiology
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• 제35권4호
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• pp.191-195
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• 2007

The colonization pattern and extent of decay produced in paddy stubble by soil inhabiting mycoflora were done by using nylon net bag technique. Among the three methods used for isolation of fungi, dilution plate technique recorded the highest number of fungi followed by damp chamber and direct observation method. Nutrient availability and climatic conditions (temperature, humidity and rainfall) influenced the occurrence and colonization pattern of fungi. Maximum fungal population was recorded in October ($48.99{\times}10^4/g$ dry litter) and minimum in May ($11.41{\times}10^4/g$ dry litter). Distribution of Deuteromycetous fungi was more in comparison to Zygomycetes, oomycetes and ascomycetes. In the early stage of decomposition Mucor racemosus, Rhizopus nigricans, Chaetomium globosum and Gliocladium species were found primarly whereas at later stages of decomposition preponderance of Aspergillus candidus, Torula graminis, Cladosporiun cladosporioides and Aspergillus luchuensis was recorded.

• Applied Biological Chemistry
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• 제17권1호
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• pp.54-62
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• 1974

전국(全國)에 걸쳐 수집한 62개(個)의 변질미(變質米) 시료(試料)를 외관상(外觀上)의 변색(變色)으로 그 유형(類型)을 구별(區別)하고 그 원인(原因)이 되는 균군(菌群)을 분리(分離) 조사(調査)하여 다음과 같은 결과(結果)를 얻었다. 1. 62개(個)의 변질미(蠻質米)는 그 변색(變色)의 외관(外講)으로 황적색(黃赤色) 적황적색(赤黃赤色), 담적색(淡赤色), 적회색(赤灰色), 농회색(濃灰色) 및 바구미(米)의 7개유형(個類型)으로 분류(分類)하였다. 2. 62개(個)의 시료(試料)에서 곰장이류 5속(屬) 44종(種), 효모류(酵母類) 1속(屬) 1종(種), 세균류(細菌類) 4속(屬) 14종(種)을 분리(分離)하였다. 3. 분리(分離)된 총균군중(總菌群中) 72.4%는 곰팡이류(類)이었으며 27.6%가 세균류(細菌類)이었다. 곰팡이 유중(類中)에는 Asp. glaucus군(群)이 38%, Asp. candidus가 14%, Asp. oryzae가 12%, Asp. versicolor가 8%로 거의 대부분이며 기타의 Aspergillus, Penicillum, Rhizopus, Scopulariopsis 그리고 Trichoderma등(等)이 있었으며 세균류중(細菌類中)에 는87%가 Bacillus이었으며 Pseudomonas가 10%, 기타 Baveiacterium과 Staphylococus등(等) 분리(分離)되었다. 4. 변색(變色)과 균군(菌群)의 관계(關係)는 절대적(絶對的)은 아니지만 황적색(黃赤色)에서는 Pen. islandicum, 담황적색(淡養赤色)에서는 Asp. candidus, Asp. clavatus, 담적색(淡赤色)에서는 Asp. glaucus, Asp. candidus, Asp. versicolor, Asp. fumigatus등(等)이, 담회황색(淡灰黃色)에는 Asp. oryzae, 담회색(淡灰色)과 농회색(濃灰色)에서는 Asp. glaucus 및 Pencillium종류(種類)가 주(主)로 분리(分離)되었다. 5. 유독성(有毒性) 물질생성균(物質生成菌)은 Asp. glaucus, Pen. islandicum, Pen. citrinum, Asp. flavus, Asp. ochraceus등(等)이 있으나 그 출현빈도(出現頻度)는 중요(重要)한 것이 아니었다. 그러나 Pen. islandicum은 높은 생육밀도를 보여서 문제(問題)가 될 수 있겠다.

• Applied Biological Chemistry
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• 제40권4호
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• pp.352-356
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• 1997

식물배양세포계에서 유용 phytoalexin의 생산여부를 검토하기 위하여 페튜니아 배양세포주에 5종의 naphthoquinone류 화합물을 첨가하였을 때 유도되는 항미생물활성을 조사하였다. 처리한 naphthoquinone류 화합물 중 토양 방선균으로부터 페튜니아 세포생장억제물질로 분리한 2,5,7-trihydroxy-3-(5'-hydroxyhexyl)-1,4-naphthoquinone (3-OH NQ)이 48시간 이내에 90% 이상 효율적으로 배양세포내로 흡수되었다. 3-OH NQ를 처리한 페튜니아 캘러스 추출물은 Aspergillus candidus의 포자발아를 강하게 억제하였다$(MIC:\;32\;{\mu}g/ml)$. 3-OH NQ를 처리한 페튜니아 배양세포로부터 2종의 항미생물 활성물질 4,2',4',${\beta}$-tetrahydroxychalcone과 4',7-dihydroxyflavone을 분리하였다. 주로 유도되는 phytoalexin인 4,2',4',${\beta}$-tetrahydroxychalcone은 A. candidus의 포자발아를 강하게 억제하였다$(MIC:\;16\;{\mu}g/ml)$.