• Food Science of Animal Resources
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• v.36 no.4
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• pp.463-468
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• 2016

Contamination by foodborne pathogens and mycotoxins was examined in 475 eggs and 20 feed samples collected from three egg layer farms, three egg-processing units, and five retail markets in Korea. Microbial contamination with Salmonella species, Escherichia coli, and Arcobacter species was examined by bacterial culture and multiplex polymerase chain reaction (PCR). The contamination levels of aflatoxins, ochratoxins, and zearalenone in eggs and chicken feeds were simultaneously analyzed with high-performance liquid chromatography coupled with fluorescence detection after the post-derivatization. While E. coli was isolated from 9.1% of eggs, Salmonella species were not isolated. Arcobacter species were detected in 0.8% of eggs collected from egg layers by PCR only. While aflatoxins, ochratoxins, and zearalenone were found in 100%, 100%, and 85% of chicken feeds, their contamination levels were below the maximum acceptable levels (1.86, 2.24, and 147.53 μg/kg, respectively). However, no eggs were contaminated with aflatoxins, ochratoxins, or zearalenone. Therefore, the risk of contamination by mycotoxins and microbes in eggs and chicken feeds is considered negligible and unlikely to pose a threat to human health.

• Toxicological Research
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• v.6 no.2
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• pp.159-166
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• 1990

The ability of many toxigenic fungi to invade and develop in a wide variety of raw ingredients of human diet renders human exposure to mycotoxing very difficult to avoid. Most of the energy-rich commodities, such as cereal grains, oil seeds, tree nuts, and dehydrated fruits, are susceptible to mycotoxin contamination. Mycotoxins therefare have been recognized as an important class of hazardous substances in the human food chain. Although human exposure to mycotoxins is largely through ingestion, inhalation and skin contact may also be significant under conditions other than consumption of foods. Human ingestion of mycotoxins is due to consumption of contaminated dietary ingredients and the edible tissues and products of domestic animals that have been exposed to mycotoxins in moldy feed. Large scale acute human mycotoxicoses, such as ergotism in France, alimentary toxic aleukia in Russia, yellow rice syndrome in Japan, endemic nephropathy in Balkan countries, and acute aflatoxin poisonings in India and Taiwan, have been well documented, indicating that mycotoxicosis is a global problem. In some incidents, hundreds of victims were killed and many more became seriously ill. The mycotoxins that have been implicated in the etiology of these human diseases include aflatoxins, citreoviridin, cyclopiazonic acid, ergot alkaloids, moniliformin, ochratoxin A, trichothecenes, tenuazonic acid, and zearalenone. Among these, aflatoxins have been also implicated in the etiology of human primary liver cancer in those high-incidence countries in Africa and southeast Asia. It is well recognized that cause-effect relationship between mycotoxins and human diseases is very difficult to establish, especially for the cancer connection. Careful risk assessment must be performed to determine whether a mycotoxin indeed warrants costly regulatory actions.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.507-513
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• 2004

Aflatoxins are produced mainly by Aspergillus flavus and Aspergillus parasiticus that grow in improperly stored cereals. Aflatoxin B1 ($AFB_1$) is a potent hepatocarcinogen in a variety of experimental animals including human beings. In spite of a high attention to the hepatocarcinogenecity of $AFB_1$, the relative toxicity of aflatoxins ($AFB_2$ and $AFG_1$) is not fully clarified. Sprague-Dawley male rats were orally administered with $AFB_1$, $AFB_2$, and $AFG_1$ at the dose of 250 ${\mu}g/kg$ (additionally including a dose of $1250{\mu}g/kg $ for $AFB_1$) body weight. Animals were then killed at 12, 24 or 48 hrs following aflatoxin exposure. Subsequently the immunohistochemical examination of p53, cytochrome p450 1A1 (CYP450 1A1), and glutathione-S-transferase placental form (GST-P) were performed. The level of the 8-OxodG in the liver was determined. Expressions of CYP450 1A1 and p53 were high in the liver of rats through 48 hrs after treatment of $AFB_1$ at the single dose of $250{\mu}g/kg $. This pattern was more clear as increasing doses. The treatment of $AFB_2$ and $AFG_1$ did not affect the expression of CYP450 1A1 but it caused weak expression of p53. The activity of GST were not found in the liver of rats treated with aflatoxins. The formation of 8-OxodG by $AFB_1$ increased in a dose-dependent manner up to 24 hrs after a single treatment of $AFB_1$ thereafter decreased to the level of control. The treatment of $AFB_2$ and $AFG_1$ did not affect the levels of 8-OxodG in the liver of rats with increasing time. These results in the present study indicate that $AFB_1$ among aflatoxins with low comparable levels is the most toxic as determined by early biomarkers such as CYP450 1A1, p53, GST-P, and 8-OxodG.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.65-72
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• 2010

We used fluorescence detector to analyse total aflatoxins (G1, G2, B1, B2) with TFA (Trifluoroacetic acid) derivation method and PHRED (Photochemical reactor enhanced detection) method. PHRED method was superior in reproduction and convenience, but TFA derivation method was superior in selectivity and sensitivity. The recovery rate of aflatoxin B1, B2, G1 were more than 80%, and G2 was more than 70%. The detection limit of B1, B2, G1 and G2 were respectively 0.05, 0.05, 0.2 and $0.1\;{\mu}g/kg$. Confirmed method was used to analyse total aflatoxins in total 316 items as 9 kinds 137 dried fruits and 10 kinds 179 spices. By the result, Aflatoxins were detected in 27 dried fruits (19.7%) and in 87 spices (48.6%).

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.177-181
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• 1985

Aflatoxin production by Aspergillus parasiticus NRRL 2999 with two different levels of inoculum sizes ($10^2$ and $10^6$ spores) was studied on such varieties of soybeans produced in Korea as Bongeui, Hwang Keum, Jangbaek, Danyeop, Jangyeop and Namcheon. With the inoculum size of $10^2$ spores/10 g of soybeans, there were statistically difference (p<0.05) on the production of aflatoxins in the varieties of soybeans. The variety of Namcheon produced 7 times higher amount of aflatoxin $B_1$ than that of Bongeui. The variety of Jangyeop produced the highest level of aflatoxin $G_1$ among the varieties employed. Namcheon and Jangyeop were the varieties which supported high amounts of aflatoxins. Much higher levels of aflatoxins were obtained on the soybeans than on rice in general with the inoculum size of $10^2$ spores. With the inoculum size of $10^6$ spores/10 g of soybeans, significantly lower levels of aflatoxins were synthesized by the mold than those with $10^2$ spores. The variety of Namcheon resulted in the lowest production of aflatoxin $B_1$ while Hwangkeum was the variety that produced highest amount of aflatoxin $B_1$. There were no significant differences within the varieties on the production of aflatoxin $G_1$ by the mold except the variety of Hwangkeum. Lower quantities of aflatoxin $B_1$ were produced by the mold en the soybeans than on rice with the inoculum size of $10^6$ spores.

• Food Science and Preservation
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• v.22 no.5
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• pp.758-767
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• 2015

Red pepper powder sensitive to aflatoxins contamination is major ingredients of kimchi. This study was conducted to investigate the effect of lactic acid bacteria (LAB) on the changes in aflatoxin levels during kimchi fermentation. Baechu kimchi was contaminated with aflatoxins ($B_1$, $B_2$, $G_1$, and $G_2$) and inoculated with LAB (Lactobacillus plantarum and Leuconostoc mesenteroides), and the following characteristics were investigated for 8 weeks: pH, titratable acidity, salinity, microbial properties, and aflatoxin levels. The pH decreased rapidly during storage, and the titratable acidity was increased. The salinity of the samples was shown to increase from 2.30 to 2.40%. The total number of aerobic bacteria and lactic acid bacteria in kimchi inoculated with LAB was significantly higher than that of the others. Yeast and molds were detected at approximately 1~3 log CFU/g during storage. Coliforms were detected in the control after 4 weeks, whereas in other samples they were not detected until after 2 weeks. The aflatoxin levels reduced during kimchi fermentation. The average reduction rate of aflatoxin levels during kimchi fermentation was 8.39%, but in kimchi inoculated with Lac. plantarum and Leu. mesenteroides, the rate were 25.16 % and 27.86%, respectively. These results showed that aflatoxins can be removed by LAB during kimchi fermentation.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.04a
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• pp.110-111
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1686-1689
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• 2003

The ability of ten probiotic bacteria to bind a common food carcinogen aflatoxin $G_1$,$G_2$ and $B_2$ was assessed. The strains were incubated in vitro with aflatoxins and the toxin residues in the supernatant were measured using high performance liquid chromatography. The aflatoxin $G_1$ binding capacity of the strains was found to strain dependent, most efficient binding of AF$G_1$ was observed by L. acidophilus CU028 and L. brevis CU06 which bound approximately 50%. L. acidophilus CU028 was capable of bind approximately 67% of AF$G_2$, difference in their binding ability showed statistical significance (p>0.05). L. acidophilus CU028 and L. helveticus CU 631 were the best binders and the strains were observed to possess variable AF$B_2$-binding ability in the range was from 38.0% to 55.9%. Lactobacillus acidophilus CU028 was the best common binders of the three types of food carcinogen aflatoxins. The application of binding phenomenon in the removal of mycotoxins from contaminated feeds is urgently needed to improve the safety of feeds.

• Toxicological Research
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• v.25 no.3
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• pp.125-131
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• 2009

Korea is representative of a country that consumes herbal medicines; most of the herbal medicines circulating in South Korea have been imported from developing countries in Southeast Asia, such as China and Indonesia. Recently, domestic hygiene and safety are issues that have come to the forefront, because herbal medicines currently in circulation could possibly contain contaminants or residues. Furthermore, the appearance or discovery of harmful new species due to environmental and industrial developments is becoming a social problem. Therefore, it may be necessary to consider and investigate these matters on a continual basis. Recently, mycotoxin contaminations in such foods as cereals, nuts, and powdered red pepper have been reported. They have become a problematic issue; the possibility of contamination in herbal medicines has also been considered. Nevertheless, recognition of and research into mycotoxin contamination in herbal medicines has been scarce because herbal medicine is used in only a few nations. In this research, we identified contamination by aflatoxin which is known to be the most potent mutagenic, carcinogenic, and teratogenic mycotoxin in Thujae Semen, a herbal medicine. We also found co-contaminations involving other mycotoxins, including ochratoxin A and zeraleanone.

• Proceedings of the Korean Environmental Health Society Conference
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• 2002.04a
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• pp.55-56
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• 2002

Aflatoxin is a secondary fungal metabolite and is a public health hazard because it is a human carcinogenic and has many deleterious effects in men and animals. Rice is one of the better substrates for the fungus which can produce aflatoxins. This study was performed to investigate aflatoxin reduction during the cooking and processing of rice. Aflatoxin was produced by Aspergillus parasiticus ATCC 15517 on well-milled rice(Japonica type) at the level of 13.2 ppb. Cooked rice, rice cakes (baek-sol-gi, plain steamed rice bread), fermented rice (sik-hye, sweet rice beverage), and popped rice were prepared from the aflatoxin-contaminated rice. Aflatoxin content in the samples was determined by high performance liquid chromatography. The total aflatoxin level was decreased to 46.9％ in the cooked rice, 85.6％ in the rice cakes, 11.4％ in the fermented rice, and 7.6％ in the popped rice, respectively (p＜0.05). This reduction brought the level of aflatoxins down to below the Standard and Specification of Korea (10 ppb), except for the rice cakes. These results indicate that washing, steaming, fermentation, and popping of rice was helpful in reducing the aflatoxin level in the rice and the most helpful factors were high temperature & high pressure. More research is needed to understand why the preparation of rice cakes did not reduce the level of aflatoxin as much as the other cooking methods.