• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.219-224
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• 1995

The antimutagenic effects of 46 kinds of medicinal plants that have been used as traditional folk antitumor agents in Korea were studied by using Ames mutagenicity test. Most of the methanolic extracts from the plants which were used in this experiment showed strong antimutagenic activity toward aflatoxin B1(AFB1) in Salmonella typhimrium TA100 and TA98. However, N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) induced mutagenicity was not blocked by adding the methanolic extracts of the plants except persimmon leaves (Diospyros kaki Thunberg)and Elaeagnus umbellata.

• Journal of the Korean Society of Safety
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• v.11 no.4
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• pp.84-89
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• 1996

The Oxidation of aflatoxin $G_1$ ($AFG_1$) with ozone in chloroform solvent gave the stable ozonide into ozonization of the double bond in the terminal furan ring, and this reaction have been carried out for 3hr at -78. 5$^{\circ}C$. The chloroform solvent was removed in a stream of nitrogen and the residue was separated by elution chromatography(EC). The structure of this compound have been identified by using MS, $^1H-NMR$, $^l3C-NMR$ and I. R spectroscopy, respectively. This compound was formed the normal stable AFG$_1$-ozonide into spontaneous rearrangement after unstable ozonide according to sigmatropic rearrange ment dependent upon cyclo addition by ozone.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.702-710
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• 2011

The occurrence of aflatoxins $B_1$, $B_2$, $G_1$ and $G_2$ in nuts, their products and dried fruits was investigated. Samples were collected from local markets in Seoul and analyzed by rapid resolution liquid chromatography coupled with tandem mass spectrometry using an immunoaffinity column. The chromatography method was validated for assay of aflatoxins using linearity, accuracy, precision and limit of detection and quantification. The linearity in the concentration ranged from 0.10 to $20{\mu}g/kg$ with $R^2$ > 0.9999. Sample recoveries ranged from 71.1 to 97.2% with relative standard deviations below 4.5% for spiking levels from 1 to $10{\mu}g/kg$. The limits of detection ranged between 0.02 and $0.05{\mu}g/kg$ and the limits of quantification ranged between 0.05 and $0.10{\mu}g/kg$. The levels of aflatoxin $B_1$, $B_2$, $G_1$ and $G_2$ in nuts, their products and dried fruits were $B_1$ 0.10 to $9.94{\mu}g/kg$, $B_2$ 0.08 to $1.54{\mu}g/kg$, $G_1$ 0.04 to $3.21{\mu}g/kg$ and $G_2$ 0.06 to $0.14{\mu}g/kg$.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.24-33
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• 2021

For this study, we surveyed concentrations of 8 mycotoxins (aflatoxin B1, B2, G1, G2, ochratoxin A, fumonisin B1, B2 and zearalenone) in agricultural products used for food and medicine by liquid chromatography-tandem mass spectrometry and conducted a risk assessment. Samples were collected at the Yangnyeong Market in Seoul, Korea, between January and November 2019. Mycotoxins were extracted from these samples by adding 0.1% formic acid in 50% acetonitrile and cleaned up by using an ISOLUTE Myco cartridge. The method was validated by assessing its matrix effects, linearity, limit of detection (LOD), limit of quantification (LOQ), recovery and precision using four representative matrices. Matrix-matched standard calibration was used for quantification and the calibration curves of all analytes showed good linearity (r2>0.9999). LODs and LOQs were in the range of 0.02-0.11 ㎍/kg and 0.06-0.26 ㎍/kg, respectively. Sample recoveries were from 81.2 to 118.7% and relative standard deviations lower than 8.90%. The method developed in this study was applied to analyze a total of 187 samples, and aflatoxin B1 was detected at the range of 1.18-7.29 ㎍/kg (below the maximum allowable limit set by the Ministry of Food and Drug Safety, MFDS), whereas aflatoxin B2, G1 and G2 were not detected. Mycotoxins that are not regulated presently in Korea were also detected: fumonisin (0.84-14.25 ㎍/kg), ochratoxin A (0.76-17.42 ㎍/kg), and zearalenone (1.73-15.96 ㎍/kg). Risk assessment was evaluated by using estimated daily intake (EDI) and specific guideline values. These results indicate that the overall exposure level of Koreans to mycotoxins due to the intake of agricultural products used for food and medicine is unlikely to be a major risk factor for their health.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.346-352
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• 2007

Contamination of aflatoxins(AFs) was monitored in 447 compound feeds and 138 feed ingredients samples distributed in South KOREA in 2006 and 2007. The degree of $AFB_1\;and\;AFB_2$ contamination in compound feed was 20% and 3%, respectively. The levels of detection were ranged from 0.48 to 10.46 ppb for $AFB_1$ and from 0.25 to 0,42 ppb for $AFB_2$. Thirty eight percent of compound feeds were contaminated with $AFB_1$ at concentration between 0.43 and 5.52 ppb and $AFB_2$ was detected in 2% of compound feeds at levels ranging 0.26-0.40 ppb. The highest degree of $AFB_1$ contamination was observed in compound feeds for beef cattle (75%) followed by for dairy cattle (72%) and in bran among feed ingredients (30%). Bran exhibited the highest level of $AFB_1$contamination (3.1 ppb). Vegetable proteins and compound feeds for dog showed relative lower degree of contamination at 2.9 and 1.9 ppb, respectively. $AFG_1\;and\;AFG_2$ were not detected in any compound feeds and feed ingredients samples.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.25-28
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• 2007

A survey of total aflatoxin levels was conducted on 565 food samples (cereals, nuts, etc) collected in commercial markets. The determination of aflatoxins ($B_{1}$, $B_{2}$, $G_{1}$ and $G_{2}$) was performed using HPLC with fluorescence detector. The Limit of Detections (LODs) of the B group and G group were 0.05 ng/g and 0.07 ng/g, respectively. In addition, recoveries of rice, peanut butter, and red pepper flour were satisfactory. Total aflatoxin was detected 27 samples(4.8%) out of 565 samples. Incidence ratios in cereals, nuts, processed products, and other foods were 0.2, 0.4, 3.0 and 1.2%, respectively, but aflatoxin was not detected in pulse and dried fruits. The daily intake of total aflatoxin using food intakes was 0.04 ng/kg bw/day.

• The Journal of the Korea Contents Association
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• v.7 no.5
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• pp.102-109
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• 2007

This is an analysis study about the pictorial frame of Georges Schwizgebel's animation "The Subject of Picture", focusing on Deleuze's frame theory. First of all, the shapes in the frame of the animation is the representation of the tactile sensation from the erased vestiges of the characters. It shows the metamorphosis of the erased vestiges of the shapes by Deleuze's sensibility theory. Besides, the layout of the animation's background has similar property with the aplat which was mentioned by Deleuze. It means that the background of the animation correspond to the aplat which is other boundary different from reality, and the character which has the minimum embodiment about the object makes the shape newly through the distortion of the shape. Secondly, as the problem of frames in terms of the continuity of time, the meaning in Schwizgebel's animation is created by the relation between each frame. It means that the depiction of the shape itself by the composition between each frame is composed of the frame. Eventually, Schwizgebel's work is the animation which has the characteristic of the modem cinema and is the crystal depiction that deviates from rules and logics of the object which was mentioned by Deleuze.

• 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%).

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.282-288
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• 2014

In this study, we attempted to isolate fungi from soybean fermented foods produced in Sunchang County and to identify Aspergillus oryzae from fungal isolates. Ten fungal isolates were identified with ${\beta}$-tubulin gene. According to the sequences of ${\beta}$-tubulin gene, ten fungal isolates were identified as A. oryzae/flavus complex. For further identification of the ten of fungal isolates, omtA gene, one gene of the aflatoxin biosynthesis gene cluster, was sequenced and the sequences were compared with those of A. oryzae and A. flavus strains from the GenBank database. In addition, identification of the ten fungal isolates was further confirmed using the PCR amplicon of norB and cypA intergenic region, in which a deletion was recognized relative to A. flavus and A. parasiticus. The amplicon size of the ten fungal isolate strains was smaller than those of A. flavus and A. parasiticus, but the same as that of the reference A. oryzae strain. These results indicated that the ten isolates should be identified as A. oryzae. The protease activity in rice koji made with 6, 13, 17, 27, 37 and 38 of strain, respectively was twice higher than that in control. The kojis made with nine of the A. oryzae isolates, respectively, did not produce aflatoxin, suggesting that the strains could possibly be used as starters for soybean products.

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.303-313
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• 2021

Peanuts in storage were estimated for mycotoxigenic fungi and mycotoxins. Peanut samples collected from storages in Gochang were mainly contaminated with Fusarium (17.2±28.0%), Penicillium (12.4±28.0%), and Aspergillus (8.0±7.6%). Other genera, including Talaromyces, Rhizopus, Rhizoctonia, Trichocladium, Clonostachys, Mucor, Chaetomium, Trametes, Epicoccum, and Humicola, were also found. Although aflatoxins were not detected in the peanut samples, 29 strains of Aspergillus flavus were identified using molecular marker genes. Among them, 17 selected isolates produced aflatoxins in solid culture media ranging from 0.61-187.82 ㎍/kg. All of them could produce both aflatoxin B₁ and B₂ and some (n=5) produced additional G₁, G₂, or both. This study is the first report that A. flavus stains obtained from Korean stored peanut are aflatoxigenic.