• 한국식품위생안전성학회지
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• 제7권1호
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• pp.1-6
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• 1992

Two Rice cultivars , a high yield variety of Cheongcheong and a Korea native kind of Chucheong were grown in paddy. 1$\mu\textrm{g}$ and 10$\mu\textrm{g}$ of aflatoxin B1 and Aspergillus flavus (106 conidia/ml) were inoculated at milk stage. At harvest, kernels from the inoculated plant showed slightly lower ripening rates and 100-grain weight than did those of controls. The nutrient and fatty acid composition of unpolished rice of inoculated group were similar to those of controls and difference between the control and inoculated group were not significantly different.

• 미생물학회지
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• 제9권3호
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• pp.130-138
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• 1971

배양조건에 따른 aflattoxin 생성능을 알기위하여 증대두배지에 Aspergillus flavus를 PH5.0 PH7.0 PH9.0 수분30%,45%,63%, 온도 2$0^{\circ}C$ 3$0^{\circ}C$ 4$0^{\circ}C$등의 조건으로 각각 배양한 27종의 시료와 Bacillus와 혼합배양한 3종의 시료를 AOAC 공정법에 의하여 aflatoxin의 생성량을 실험한 결과 다음과 같은 겨로가를 얻었다. 1. 각 PH에 의한 aflatoxin의 생성량은 PH5.0의 경우가 높았으며 PH7.0의 경우도 비교적 높은 편이었으나 PH9.0에서는 aflatoxin생성량이 현저히 감소되었다. 2. 수분합량에 따른 aflatoxin의 생성량은 수분이 적은 30%의 경우, 비교적 많은 양의 aflatoxin을 얻을 수 있었으며, 그 다음이 45%, 63% 으로서 수분함량이 많아질수록 aflatoxin의 생성이 감소되었다. 3.온도조건이 의한 결과는 Aspergillus flavus를 2$0^{\circ}C$로 배양하였을 때 가장 높은 aflatoxin의 생성량을 볼 수 있었으며, 3$0^{\circ}C$의 경우도 비교적 높은 양의 aflatoxin 생성을 볼 수 있으나 4$0^{\circ}C$의 경우는 aflatoxin의 생성은 낮았다. 4.여러가지 배양조건에 따른 Aspergillus flavus의 aflatoxin생성량은 수분 30% PH5.0 온도2$0^{\circ}C$일때 crude aflatoxin은 5.093ppm로 가장 높았으며 수분함량 63% PH 9.0 온도 4$0^{\circ}C$일때 crude aflatoxin의 량은 2.197ppm으로 aflatoxin 생성이 가장 낮았다. 5. Aspergillus flavus를 여러 조건하에서 배양한 결과 가장 많이 생성되는 배양조건인 온도 20 $^{\circ}C$ 수분 30%의 조건하에서 Bacillus subtilis와 혼합배양한 결과 Aspergillus flavus 단독배양의 경우보다 Bacillus subtilis균과 혼합배양하였을때 aflatoxin은 약 27%나 감소되었다.

• 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.

• Mycobiology
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• 제33권2호
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• pp.84-89
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• 2005

Five types of agricultural wastes were used for the production of xylanolytic enzyme by Aspergillus flavus K-03. All wastes materials supported high levels of xylanase and ${\beta}-xylosidase$ production. A high level of proteolytic activity was observed in barley and rice bran cultures, while only a weak proteolytic activity was detected in corn cob, barley and rice straw cultures. Maximum production of xylanase was achieved in basal liquid medium containing rice barn as carbon source for 5 days of culture at pH 6.5 and $25^{\circ}C$. The xylanolytic enzyme of A. flavus K-03 showed low thermostability. The times required for 50% reduction of the initial enzyme activity were 90 min at $40^{\circ}C$, 13 min at $50^{\circ}C$, and 3 min at $60^{\circ}C$. Xylanolytic activity showed the highest level at pH $5.5{\sim}10.5$ and more than 70% of the original activity was retained at pH 6.5 and 7.0. The higher stability of xylanolytic enzymes in the broad range of alkaline pH is useful for utilization of the enzymes in industrial process requiring in alkaline conditions. Moreover, the highest production of xylanolytic enzyme was obtained when 0.5% of rice bran was supplied in basal liquid medium. SDS-PAGE analysis revealed a single xylanase band of approximately 28.5 kDa from the culture filtrates.

• 한국환경보건학회지
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• 제16권1호
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• pp.45-53
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• 1990

To investigate the effect of cultural condition on the aflatoxin production of Aspergillus flayus ATCC 15517, mixed culture with Aspergillus niger, better kind of media and size of Cultural vessels were examined. YES medium was better than SLS medium for this study. Small scale test tube culture was showed the possibility to simply examine the growth, total acidity, pH and aflatoxin production during cultivation, and also could reduce the second contamination of aflatoxin B1 from large scale broth cultured. Especially ELISA method is simple, sensitive and specific and therefore well suited to small scale of test tube culture. Mixed culture significantly reduced the aflatoxin production of Aspergillus fiavus ATCC 15517 and showed almost 95% inhibition of that level during the incubtation.

• Archives of Pharmacal Research
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• 제26권5호
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• pp.389-393
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• 2003

The essential oils from Cedrus atlantica, Styrax tonkinensis, Juniperus communis, Lavandula angustifolia, Melaleuca alternifolia, Pelargonium graveolens, Pogestemon patchouli and Rosmarinus officinalis were analyzed by GC-MS. Antifungal activities of the oils were investigated by disk diffusion assay and the broth dilution method against Aspergillus niger and A. flavus. The effects of geraniol and the essential oil fraction from P. graveolens on the antifungal activity of amphotericin Band ketoconazole were examined using a checkerboard microtiter assay against both Aspergillus fungi. Most of the tested essential oils, with the exception of C. atlantica, J. communis, and P. patchouli, significantly inhibited growth of A. niger and to a lesser extent that of A. fIavus, with MICs (minimal inhibitory concentrations) in the range 0.78-12.5 mg/mL. The essential oil fraction of P. graveolens and its main components, geraniol and citronellol, exhibited additive effects with amphotericin B and with ketoconazole against both Aspergillus species, resulting in fractional inhibitory concentration (FIC) indices ranging from 0.52 to 1.00.

• 한국균학회지
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• 제1권1호
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• pp.17-21
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• 1973

Fifty-eight strains of Aspergillus spp. isolated from various grains were examined for the screening of aflatoxins by the method of the Thin-Layer Chromatography (TLC), using the aflatoxin producing strain of Aspergillus flavus ATCC 15517 as a control. The results as follows: 1. Samples of Aspergillus spp. isolated from various grains were extracted with chloroform and chromatographied by the thin-layer chromatography method. 2. Three strains of Aspergillus spp. among the 58 strains can be found that the spots having the same Rf value as control with culture extract of Aspergillus flavus ATCC 15517. 3. The further prove studies of aflatoxins were proceed by the methods of in vivo and in vitro tests. And this methods considered to capable for the use of mass screening among the samples.

• 한국균학회지
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• 제49권3호
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• pp.303-313
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• 2021

땅콩의 독성곰팡이 및 곰팡이독소 오염현황을 조사하기 위해 고창 지역의 저장고에서 땅콩을 수집하였다. 수집된 땅콩은 Fusarium (17.2±28.0%), Penicillium (12.4±28.0%), Aspergillus (8.0±7.6%) 속 곰팡이로 주로 오염되어 있었으며, 그 외에 Talaromyces, Rhizopus, Rhizoctonia, Trichocladium, Clonostachys, Mucor, Chaetomium, Trametes, Epicoccum, Humicola 속 곰팡이가 검출되었다. 땅콩시료에서 아플라톡신은 검출되지 않았으나, 29점의A. flavus 균주가 분리, 동정되었다. 그 중 17점의 균주를 선발하여 potato dextrose agar (PDA) 배지 상에서 아플라톡신 생성능을 분석한 결과 0.61-187.82 ㎍/kg의 농도범위에서 모두 아플라톡신을 생성하였다. 이들 17 균주는 아플라톡신 B₁, B₂도 생성하였으며, 일부(5 균주)는 G₁ 또는 G₂를 생성하였다. 이 연구는 국내 저장 땅콩에서A. flavus 오염률 및 독소생성능에 대한 첫 보고이다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 춘계학술대회 및 임시총회
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• pp.25-25
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• 2014

Koji molds are comprised of yellow, black and white. Black and white koji molds were recently re-visited by this author and it is concluded that they consists of Aspergillus luchuesnsis, A. niger and A. tubingensis, and the most important species for alcoholic beverage production is A. luchuensis. In the case of yellow koji mold, it is comprised of Aspergillus oryzae, A. sojae and A. tamari. In the case of A. sojae, the species is scarcely isolated from nature and rarely used for industry in Korea. Aspergillus tamari is often isolated from traditional Korean Meju, a fermented soybean product, and the classification of the species is clear. However, in the case of A. oryzae, differentiation between A. oryzae and A. flavus is still in controversy. In this study, we collected 415 strains of Aspergillus flavus/oryzae complex from air, rice straw, soybean, corn, peanut, arable soil and Meju in Korea and we examined the aflatoxin producing capacity of the strains. The norB-cypA, omtA and aflR genes in the aflatoxin biosynthesis gene cluster were analyzed. We found that 367 strains (88.4%) belonged to non-aflatoxigenic group (Type I of norB-cypA, IB-L-B-, IC-AO, or IA-L-B- of omtA, and AO type of aflR), and only 48 strains (11.6%) belonged to aflatoxin-producible group (Type II of norB-cypA, IC-L-B+/B- or IC-L-B+ of omtA, and AF type of aflR). In the case of A. flavus/oryzae strains from Meju, almost strains (178/192, 92.7%) belonged to non-aflatoxigenic group and only 14 strains (7.3 %) belonged to aflatoxin-producible group. It is proposed in this study that non-aflatoxigenic strain from Meju is classified as A. oryzae, considering that Meju is food material.

• 미생물학회지
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• 제17권1호
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• pp.16-24
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• 1979

In order to investigate the production of aflatoxin in various conditions such as pH, moisture and temperature, 27 smaples were inoculated with Aspergillus flavus, and in addition 3 smaples were inoculated with the mixture of Aspergillus flavus and Bacillus subtilis and cultured under the conditions such as $20^{\circ}C$ and 30% moisture contents. The following results were obtained : 1) Aflatoxin production was the highest at pH 5.0 and relatively high at pH 7.0. Its production was decreased significantly when pH reached 9.0. 2) The yield of aflatoxin was shown comparatively high level at 30% moisture contens. The higher moisture contents was, the lower aflatoxin production was. 3) The highest level of aflatoxin production was at $20^{\circ}C$, and comparatively high level was at $30^{\circ}C$. However, its production was fairly low at $40^{\circ}C$. 4) The highest crude aflatoxin production was 5,093ppm $(B_1,\;1.912\;ppm;\;B_2,\;0.521\;ppm;\;G_1,\;2.119\;ppm;\;G_2,\;0.541\;ppm)$ at 30% moisture, pH 5.0 and $20^{\circ}C$ and the lowest one 2.197 ppm $(B_1,\;0.793\;ppm;\;B_2,\;0.185\;ppm;\;G_1,\;0.102\;ppm;\;G_2,\;0.381\;ppm)$ at 63% moisture, pH 9.0 and $40^{\circ}C$ 5) When Aspergillus flavus and Bacillus subilis were cultured together under the conditions such as $20^{\circ}C$ and 30% moisture, aflatoxin production was decreased by 27% comparing with the culture of Aspergillus flavus alone.