• Applied Biological Chemistry
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• v.47 no.1
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• pp.1-16
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• 2004

The purpose of this paper is to review the occurrence, analytical methods and reduction methods of aflatoxins in foods. Aflatoxins are produced by the secondary metabolism of various fungal species and have the highest toxicity among mycotoxins. Due to their toxicity including carcinogenic activity, aflatoxins affect not only the health of humans ana animals but also the economics of agriculture and food. As a food-importing country, because aflatoxins could contaminate raw commodities and foodstuffs, there should be inspection on the exposure and the regulation of risk assessment as a food safety measure. In addition, studies on rapid analytical methods and reduction of toxicity by various processes for aflatoxins should be carried out in conjunction with those of the risk assessment of aflatoxins.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.46-50
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• 1978

Aflatoxin, a mixture of the at least four toxic and carcinogenic metabolites, is known to be produced by only a few fungi. The toxins were designated aflatoxins because they were produced by the mold Aspergillus flavus(A. flavus). However, at least four other toxins and other species of the genus A. niger, A. parasiticus A. ruber and wentii have been reported to produce aflatoxins. And also the identical compounds may also be produced by molds, the Pencillium. At least four different species of Penicilliurn have been reported to produce aflatoxins (P. citrinurn, P. frequentans, P. puberulurn. and P. variable). So it is now known that the problem of Aflatoxin is not restricted to the single species A. flavus, even though that is a very common mold. Also additional aflatoxins have been discorvered. For sereral years, only four aflatoxins were known: $B_1, B_2, G_1$ and $G_2$, so designated by reason of their fluorescence and chromatographic charateristics. It is now known that there are really two new toxic materials in the milk. During the past year(1966) they were christened aflatoxin $M_1$ and $M_2$, since they were first found in milk. The two other and most recently discorvered aflatoxins were isolated late in 1966 from cultures of A. flavus, and were designated aflatoxin $B_2a$ and aflatoxin $G_2a$. In order to obtain a breaf information about extent of contamination of foodstuffs by aflatoxin which is known to produce eight different mold, aflatoxin detection of cereals and fermented foods on sale, such as polished rice, barley, wheat, wheat flour, lentil, red bean, soy bean, noodle, kochuj ang and Dwenjang (fermented soy bean paste) and chong Kuk, were carried out. The results of this investigation were summarized as follows: The hexane:$CHCl_3$ extracts of polished rice, barley wheat, wheat flour, lentil, red bean, noodle and kochujang yielded fluorescent spots on thin layer plates. However their Rfvalues were different from those of authentic aflatoxins. The fluorescent substances of the extract from soy bean, Dwenjang and chong kuk showed very similar Rf values to those of the standard aflatoxins. By two dimensional thin layer chromatography and comparison of ultra violet absorption spectra, it was found that these fluorescent substances were not aflatoxins. To conclude, aflatoxins themselves were not detected directly in those samples tested.

• Journal of Environmental Health Sciences
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• v.18 no.2
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• pp.52-56
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• 1992

The ability of chemicals, 10% sodium hypochlorite, 28% ammonium hydroxide, 5% sodium hydroxide, 5% sodium bicarbonate, 0.1% hydrochloric acid, 5% hydrogen peroxide, and 5% acetone, to destroy aflatoxins in laboratory waste water containing 3.26 ppb of B$_{1}$ 7.64 ppb of B$_{6}$3 ppb of G$_{1}$, and 11.39 ppb of G$_{2}$ with the total of 29.11 ppb was investigated. High performance liquid chromatograph (HPLC) was used for the separation and quantitation of aflatoxins. Treatment for 2 hours by the chemicals affected the destruction of aflatoxins and the most effective chemical was 10% sodium hypochlorite (p<0.05). Sodium hypochlorite concentrations more than 1% significantly reduced aflatoxin B$_{2}$, G$_{1}$, G$_{2}$ and total aflatoxins and more than 3% reduced B$_{1}$ (p<0.05). No further significant decreases were observed above the concentration of 5% for all 4 aflatoxins. Complete destruction of aflatoxins B$_{2}$, G_{1}$, and G$_{2}$ was achieved by 5% sodium hypochlorite at 48 hours and B$_{1}$ at 72 hours.

• Mycobiology
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• v.42 no.4
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• pp.339-345
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• 2014

During 2011~2013, a total of 729 samples for 19 types of medicinal plant were collected from Seoulyekryungsi in Seoul, Korea, and investigated for the presence of aflatoxins. The samples were analyzed using immunoaffinity column cleanup and high-performance liquid chromatography coupled to a fluorescence detector after post-column derivatization. Aflatoxins were found in 124 out of the 729 analyzed samples: 65 containing aflatoxin B1 (AFB1), 24 with aflatoxin B2 (AFB2), 15 with aflatoxin G1 (AFG1), and 20 samples with aflatoxin G2 (AFG2). The ranges for positive samples were $0.1{\sim}404.7{\mu}g/kg$ for AFB1, $0.1{\sim}10.0{\mu}g/kg$ for AFB2, $0.1{\sim}635.3{\mu}g/kg$ for AFG1, $0.1{\sim}182.5{\mu}g/kg$ for AFG2, and $0.1{\sim}1,043.9{\mu}g/kg$ for total aflatoxins. Most of the medicinal plant samples (721, 98.9%) were below legal limits, but 8 samples exceeded the legal limits of 10 and $15{\mu}g/kg$ established by the Korean standard for AFB1 and total aflatoxins (the sum of AFB1, AFB2, AFG1 and AFG2), respectively.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.77-86
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• 1976

This study was attempted to know that the interactions of various fungi, and methionine and $MgSO_4$ introduced as the substrate of culture media for fungi were affected to produce aflatoxins by Asp. flavus. 5 different fungi were isolated from the fermented soybean mash and were cultured in Chemically Defined medium (C. D. media) and soybean mash at $25^{\circ}C$ for 10 days. (1) It was confirmed that Asp. flavus produced aflatoxins in the C. D. medium and soybean mast, but that Asp. niger, Asp. oryzae, Asp. awamori and Asp. terreus did not produced them respectively. (2) Asp. flavus cultured with Asp. niger did not produce aflatoxins in C. D. medium, but produced in soybean mash, in other hand, Asp. flavus with other fungi except Asp. niger produced aflatoxins in C. D. medium and soybean mash. (3) The growth of fungi were more prosperous in the seperate culture than in the mixed culture. (4) In the C. D. medium added 20% of cultured medium of Asp. niger, Asp. flavus did not produce aflatoxins but other cultured medium did not prohibit the production of aflatoxins by Asp. flavus. (5) On the contrary, $MgSO_4$ increasing the productivity of aflatoxins by Asp. flavus in the C. D. medium, methionine known as one of precursor of aflatoxins did not affected the increasing productivity with significance.

• Journal of Preventive Medicine and Public Health
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• v.2 no.1
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• pp.1-4
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• 1969

35 samples of Korean fermented foodstuffs were tested to isolate and to identify for aflatoxins. Aflatoxin $G_1$ was detected in samples of soybean and Kanjang (Soybean sauce), and aflatoxins $G_1$ & $G_2$ in Meju (fermented soybean mass) and Dwenjang (fermented soybean paste). In the culture media of Aspergillus flavus aflatoxins $B_1,\;B_2,\;G_1\;and\;G_2$ were also isolated and identified. Aflatoxins were confirmed by the thin layer chromatography with methanol : chroroform (5:95v/v) developer and the ultra violet absorption spectrum.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.05a
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• pp.58-58
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• 2003

Aflatoxins are metabolites of fungi Aspergillus spp. that world-widely contaminate diverse foodstuffs including com and peanuts. It is well known that aflatoxins are highly mutagenic, carcinogenic and possibly teratogenic. Although aflatoxins have received the great attention among the various mycotoxins due to their potent hepatocarcinogenicity in certain species, it is extremely crucial to elucidate the relative toxicity and carcinogenicity of the types (B$_1$, B$_2$, G$_1$ and G$_2$) of aflatoxins for the risk assessment.(omitted)

• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.149-157
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• 1996

A procedure for the determination of Aflatoxins in food and grains which utilizes reversed phased liquid chromatographic (LC) analysis with postcolumn derivatization by an electrochemical cell and determination with a fluorescence detector has been evaluated. The LC mobile phase was water-acetonitrile-methanol (6+2+2) with 1mM KBr and 1 mM HNO3 which gave baseline separation for the four Aflatoxins (AfB1, AfB2, AfG1, AfG2). The electrochemical cell set at 7V, generated bromine and derivatized aflatoxins B1 and G1, The derivatives were detected by the fluorescence detector. The aflatoxins in naturally contaminated corn samples were isolated by three different cleanup procedures: the AOAC method I column(CB method), a rapid filtrate column (Romer's column), and an immunoaffinity column. The final extract were quantitated with fluordensitometric TLC and the LC postcolumn derivatization techniques. The results were quite similar, however the LC technique showed less interferences and could be automated. Samples of corn, raw peanuts, peanut butter and dried dates were also analyzed successfully with this procedure.

• Journal of Food Hygiene and Safety
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• v.8 no.4
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• pp.251-254
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• 1993

Extraction and Clean-up procedures coupled with quantitation by high performance liquid chromatography(HPLC) was evaluated for the detection of 4 aflatoxins, B1, B2, G1 and G2, in peanut butter. The Sep-pak clean-up method showed poorer separation and repeatability than did the modified DeVries' and an immunoaffinity column clean-up methods. No significant difference of detected aflatoxins between the affinity column clean-up and modified DeVries' method. The coefficients of variation for the 4 aflatoxins were ranging from 6.3∼32.3 by the modified DeVries' method and 5.3∼9.8 by the affinity column clean-up.

• Journal of Food Hygiene and Safety
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• v.1 no.2
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• pp.171-176
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• 1986

ABSTRACT-In order to detect the aflatoxins in home-made Takju and peanut butter, the samples were collected in Chungbuk region and cleaned up Sep-pak silica cartridge. Aflatoxins were detected by thin layer chromatographic and high performance liquid chromatographic behavior. Determination was carried out by thin layer densitometer. The results were as follows; 1. Aflatoxin B, was detected in 78% of the home-made Takju, and the highest concentration was 1.2 ppb and average 0.36 ppb. 2. Aflatoxins were not detected in any peanut butter smaples. 3. Clean-up method by Sep-pak silica cartridge was more efficient and economical than column chromatography of AOAC method.method.