• 한국환경보건학회지
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• 제31권2호
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• pp.127-133
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• 2005

This study was performed to investigate the competitive effect of Leuconostoc mesenteroides and Lactobacillus plantarum on the growth and aflatoxin $B_1$ production of Aspergillus parasiticus. Leu. mesenteroides and Lac. plantarum were grown with A. parasiticus in a modified APT broth at $28^{\circ}C$ for 9 days. It was observed that the growth of A. parasiticus got lower when the two bacteria were inoculated simultaneously than when the mold grew alone. The pH of mixed culture of Leu. mesenteroides and Lac. plantarum showed significantly lower value than the pH of the pure culture of A. parasiticus (p<0.05). The acidity of the mixed culture group significantly increased compared with the control group (A. parasiticus alone group) (p<0.05). The aflatoxin $B_1$ production was significantly decreased in the mixed culture group than in the A. parasiticus alone group (p<0.05). Leu. mesenteroides showed the more efficient effect than Lac. plantarum. These results indicate that the two lactic acid bacteria have inhibitory effect on the growth and aflatoxin $B_1$ production of Aspergillus parasiticus.

• 한국약용작물학회지
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• 제11권5호
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• pp.385-391
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• 2003

본 연구에서 8종의 생약 추출물이 A. parasiticus의 배양시 aflatoxin $B_1$ 생성에 미치는 효과를 조사하였다. 배지의 pH는 배양 3일 후에 모든 생약 추출물이 pH 4 이하를 나타냈으며 구기자, 오매, 계피, 두충은 배양 6일에 다시 pH 4 이상으로 상승하였고 이중 대추가 배양 기간 중 가장 낮은 pH를 나타냈다. 균체 생성량은 모든 실험군이 대조군보다 높았으며 갈근, 두충, 오미자, 대추, 오매,구기자, 목과의 순으로 나타났다. 이중 갈근이 최대 생성량을 나타냈으며 목과가 가장 낮은 생성량을 나타냈다. Aflatoxin $B_1$은 갈근과 대추 추출물을 제외한 모든 실험군에서 생성이 억제되었다. 특히 계피, 오매, 두충 구기자, 오미자 추출물 에서 aflatoxin $B_1$ 생성이 현저히 저하되었으며 계피가 가장 큰 억제 효과를 나타냈다. 균체량이 많이 생성되면 aflatoxin $B_1$ 생성이 적어지고 균체량이 적게 생성되면 aflatoxin $B_1$의 생성이 많아졌다. Aspergillus parasiticus에 의해 aflatoxin $B_1$을 가장 적게 생성하는 계피와 가장 많이 생성하는 갈근 추출물의 총단백질 생성량은 계피는 3일째 (34.5%), 갈근 ext ract는 4일째 (36.4%) 총단백질의 함량이 최대가 되어 균체 내의 총단백질의 함량은 계피와 갈근 추출물을 첨가한 시험군이 게조군의 총단백질 함량 (32.7%)보다 약간 많았으며 aflatoxin $B_1$ 생성 및 축적이 최대가 되는 시기는 총단백질량이 최대가 되는 시기보다 대체로 1일 정도 늦게 나타났다.

• 한국식품위생안전성학회지
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• 제3권2호
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• pp.89-97
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• 1988

한의원에서 오래 전부터 사용되어 오고 있는 몇 종의 한약재를 구입하여 이들을 chloroform으로 추출하여 추출물을 조제한 다음 공시균(Aspergillus parasiticus R-716)의 생육과 aflatoxin 생성에 미치는 영향을 조사한 결과 다음과 같은 결론을 얻었다. 1. 목단 추출물 첨가군에서 가장 현저하게 공시균의 생육이 저해되었고 그 외의 첨가 군에서도 강황, 봉출, 향부자, 백작양, 백출의 순으로 저해되었다. 2. Aflatoxin 생성은 백출과 강황 추출물 첨가군에서만 저해되었고, 나머지 첨가군에서는 오히려 증가되거나 효과가 적었다. 3. 백출 추출물 0.2$m\ell$ 첨가 시 3일째부터 균체 생성을 시작하여 9일째에 0.953/30ml이었고 aflatoxin 함량은 792${\mu}\ell$으로서 대조군에 비해 약 50%가 감소되었다. 균체 g당 aflatoxin 함량은 992${\mu}\ell$으로서 대조군의 1,467${\mu}\ell$에 비해 역시 크게 감소되었으며 NADPH oxidase 활성은 대조군 보다 높아 백출추출물이 공시균의 생성과 aflatoxin 생성에 저해 효과가 있는 것으로 나타났다.

• 한국식품위생안전성학회지
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• 제13권3호
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• pp.313-317
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• 1998

본 연구는 한국 전통 된장과 간장 및 메주등에서 주된 상재균으로 나타나는 B. subtilli가 Aspergillus parasicus의 성장과 발암물질(Aflatoxin) 생성에 미치는 영향을 관찰하기 위하여 수행되었다 변형 APT 배지를 사용하여 $30^{\circ}C$에서 12일 동안 B. subtilis KCCM 11316과 Aspergillu parasiticus ATCC 15517를 단독 배양(대조군) 및 혼합 배양하고 그 성장과 배양물의 변화를 경시적으로 관찰하였으며 HPLC에 의하여 aflatoxin을 분석하였다. 혼합 배양시에는 곰팡이의 건조 균체량이 배양 직후로부터 배양 말기에 이르기까지 현저하게 억제되었으며, 배양 말기에 단독 배양시보다 85.3% 감소되었다(p<0.01). Aflatoxin의 생성량도 배양 말기에 대조군에 비하여 50%이상 감소되었다(p<0.05). 이로부터 Bacillus subtilis는 메주 및 간장과 된장에 있어서 유해 곰팡이의 생육과 aflatoxin 생성을 주도적으로 억제하는 것을 알 수 있다. Aflatoxin 생성에 대한 억제 효과는 곰팡이의 성장에 대한 억제 효과보다 낮게 나타났으나 메주 중에는 다른 발효 관련 세균들이 함께 존재하는 바, 이들에 의한 억제적 영향도 기대된다.

• Mycobiology
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• 제45권3호
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• pp.213-219
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• 2017

In our previous study, three bacterial strains, Bacillus megaterium KU143, Microbacterium testaceum KU313, and Pseudomonas protegens AS15, were selected as effective biocontrol agents against Aspergillus flavus on stored rice grains. In this study, we evaluated the inhibitory effects of the volatiles produced by the strains on A. flavus growth and aflatoxin production on stored rice grains. The three strains significantly reduced mycelial growth of A. flavus in dual-culture assays compared with the negative control strain, Sphingomonas aquatilis KU408, and an untreated control. Of these tested strains, volatiles produced by B. megaterium KU143 and P. protegens AS15 markedly inhibited mycelial growth, sporulation, and conidial germination of A. flavus on agar medium and suppressed the fungal populations in rice grains. Moreover, volatiles produced by these two strains significantly reduced aflatoxin production in the rice grains by A. flavus. To our knowledge, this is the first report of the suppression of A. flavus aflatoxin production in rice grains using B. megaterium and P. protegens volatiles.

• Advances in Traditional Medicine
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• 제5권4호
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• pp.308-315
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• 2005

Aflatoxin contamination is a major problem in several food crops. Aflatoxin, a mycotoxin, produced by Aspergillus flavus has gained immense concern in the scientific world because of its tremendous harmful effects. The study was focused to see the effect of oil and aqueous extract of neem (Azadirachta indica) seeds on the growth of Aspergillus and production of aflatoxin by the mold. Various amounts of neem oil $(5\;-\;50\;{\mu}l/ml)$ and aqueous extract of neem (5 - 50 mg/ml) were used both in the broth as well as the solid medium. Fungistatic (MIC) and minimal fungicidal concentrations (MFC) were found to be $10\;{\mu}l/ml$ and $50\;{\mu}l/ml$ respectively for neem seed oil. At the concentration of $5\;{\mu}l/ml$ neem oil and 5 mg/ml of aqueous extract, a significant decrease in the aflatoxin content was found in broth medium. Aflatoxin production was totally inhibited at $50\;{\mu}l/ml$ and 50 mg/ml for neem oil and aqueous extract of neem respectively, in both treatments. There was significant inhibition of mycelium dry weight by the neem seed oil. Mycelial growth was totally inhibited at $20\;{\mu}l/ml$ of neem seed oil concentration in broth, whereas it was not affected at all by aqueous extract. It can therefore be inferred that the oil and extract from the neem seed leads to inhibition of aflatoxin production while neem seed oil also significantly inhibits the mycelial growth. Neem seed oil thus can be used as potent, natural and easily available anti-aflatoxigenic agent.

• 한국균학회지
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• 제13권4호
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• pp.243-247
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• 1985

Experiments were conducted to study effects of steroidal carbamate derivatives upon mycelial growth and aflatoxin production by Aspergillus flavus ATCC 15517. The basal medium was supplemented with various concentrations of these compounds and inoculated with spores. The developing cultures were incubated for 11 days at $28^{\circ}C$ without agitation. Aflatoxins were extracted with chloroform, separated by thin layer chromatography, and quantitated by ultraviolet spectrophotometry. At a concentration of 50 mg per 30 ml of medium., stigmasteryl-N-(2-chloroethyl) carbamate, cholesteryl- N - (2-chloroethyl) carbamate, $5{\alpha}-cholestan-3-one-oximino-N-(2-chloroethyl)$ carbamate and ${\beta}-sitosteryl-N-(2-chloroethyl)$ carbamate were the most effective in reducing aflatoxin production by Aspergillus flavus. However, cholest-4-ene-3-one-oximino-N-(2-chloroethyl) carbamate, at a concentration of 100 mg per 30 ml, significantly decreased aflatoxin production. There was no significant inhibition of mycelial growth by the addition of the various concentrations of these compounds.

• 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.

• 한국식품위생안전성학회지
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• 제16권3호
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• pp.206-211
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• 2001

곰팡이독소 생성균과 비생성균의 혼합배양이 곰팡이독소 생성에 미치는 영향을 조사하기 위하여 Aspergillus flavus (aflatoxin 생성균), Aspergillus nigey(비생성균) 그리고 Penicillium griseofulvum (patulin 생성균)을 5 ml의 SLS 배지에서 15일동안 단독 혹은 혼합배양하였다. Afatoxin의 생성능의 측정은 직접경쟁 ELISA법으로, patulin은 HPLC 법으로 생성능을 측정하였으며, 균의 생육도, pH 그리고 산생성량을 상법에 따라 측정하였다. 그 결과 혼합배양은 전체적으로 균의 생육도를 크게 저하시키지 않은 반면, 산의 생성증가로 pH의 감소를 보였다. Aflatoxin은 12일간의 단독배양시 145 $\mu\textrm{g}$/ml이 생성되었으나 혼합배양으로 93%이상이 감소되어 10.26$\mu\textrm{g}$/ml을 생성하였다. Patulin의 경우도 혼합배양으로 단독배양시의 77.82$\mu\textrm{g}$/ml에 비하여 69.5%가 감소된 23.72$\mu\textrm{g}$/ml 수준을 나타내었다.

• 한국환경보건학회지
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• 제21권3호
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• pp.48-55
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• 1995

This study was performed to investigate the inhibitory effect of Aloe vera on the growth and aflatoxin production of Aspergillus parasiticus. Spore suspension of A. parasiticus ATCC 15517 was inoculated on the yeast-extract sucrose broth containing 0.1%, 0.5%, 1.0% and 10.0% of chloroform extract of Aloe vera and then incubated at 30$\circ$C for 7 days. Mycelial weight was 160.7 mg/5ml in control group and decreased by the addition of the extract with no significance. The mold caused decrease in pH of the media with and without the extract. pH in the group contained 10.0% of the extract showed significantly higher value of 5.10 than that of 4.90 in control group (p<0.05). Fluorescence spots of four aflatoxins were observed under the 365 nm of UV light after extraction of the media and TLC. In the result of separation and determination by HPLC, the aflatoxins were produced in the order of $B_1, G_1, B_2$ and $G_2$ in all groups. Production of aflatoxins $B_1, B_2$ and $G_1$ was reduced by the addition of the extract and decreased as amount of the extract increased. The production of aflatoxins $B_1$ and $B_2$ significantly reduced when the media contained more than 1.0% of the extract, and $G_1$ more than 0.5%, respectively(p<0.05). No reduction and no significant difference among groups were observed in case of aflatoxin $G_2$. With the above result, the extract of Aloe vera reduced the production of aflatoxin by A. parasiticus though it did not inhibit mycelial growth.