• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.1051-1056
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• 2002

In vitro binding efficacy of esterified glucomannan (E-GM) (0.1%) on aflatoxin B1 (AF) (300 ppb), ochratoxin A (OA) (2 ppm) and T-2 toxin (T-2) (3 ppm), when present alone or in combination, was evaluated in toxin-contaminated feed at pH 4.5 and 6.5. Esterified glucomannan showed significantly (p<0.01) higher binding with AF (81.6%), whereas those recorded with T-2 (27.8%) and OA (25.6%) were moderate. Binding of each toxin decreased as the number of toxins in feed increased. pH of medium showed no effect on mycotoxin binding ability of E-GM. A $2{\times}2{\times}2{\times}2$ factorial experiment of 5 week duration was conducted to study the effects of two dietary levels each of AF (0 and 300 ppb), OA (0 and 2 ppm), T-2 (0 and 3 ppm ) and E-GM (0 and 0.1%) on the immune competence of a total of 960 day-old commercial broilers. Reductions in size of thymus (by AF and T-2) and bursa (by AF) and antibody titers against Newcastle disease and Infectious Bursal disease (by all the toxins) were noted. Additive and antagonistic interactions were seen among the toxins on certain parameters. Esterified glucomannan significantly (p<0.01) improved antibody titers and weights of bursa ofFabricius and thymus indicating its counteracting efficacy against immunosuppression in mycotoxicosis of multiple origin.

• Korean Journal of Medicinal Crop Science
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• v.19 no.1
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• pp.47-53
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• 2011

HACCP methodology was applied in the post-harvest processing and storage of domestic medicinal produces. Particularly in terms of mold and mycotoxin contamination, candidate critical control points (CCP) in the conventional practice in Korean farms were selected and monitored by comparing with on the standard guided processing and storage. When each processing of Angelicae Gigantis Radix were assessed for their safety, the drying steps such as the sun drying or the thermal drying depending on each farm made differences in mold contamination. Moreover, the storage conditions before or after the processing were another critical determinant in the fungal contamination. In other words, storage under $4{\circ}C$ rather than at room temperature was favorable for reducing mold growth in the harvested crops. Occurrence rate of Aflatoxin $B_1 \;(AFB_1)$ in Angelicae Gigantis Radix were 12.8%, but amount of $AFB_1$ in all the collected samples were below 10 ppb regulatory limit allowed in Korea. However, for a few samples of Angelicae Gigantis Radix, still relatively high levels of total amount of the major aflatoxins (aflatoxin $B_1\; +\; B_2\; +\; G_1\; +\; G_2$) were observed around 0.18~49.94 ppb, which is not regulated presently in Korea. It thus can be suggested that post-harvest processing and storage of Korean medicinal crops need further investigation and monitoring to establish the Good Agricultural Practice (GAP), particularly to minimize microbial risk including mold and mycotoxin contamination under the changing climate. Additionally, it is also warranted for new enacting of regulatory limits for total aflatoxins in the medicinal crops.

• Toxicological Research
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• v.32 no.1
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• pp.81-87
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• 2016

Aflatoxin B1 (AFB1) is produced by Aspergillus flavus growing in feedstuffs. Early detection of maize contamination by aflatoxigenic fungi is advantageous since aflatoxins exert adverse health effects. In this study, we report the development of an optimized conventional PCR for AFB1 detection and a rapid, sensitive and simple screening Real-time PCR (qPCR) with SYBR Green and two pairs of primers targeting the aflR genes which involved aflatoxin biosynthesis. AFB1 contaminated maize samples were divided into three groups by the toxin concentration. Genomic DNA was extracted from those samples. The target genes for A. flavus were tested by conventional PCR and the PCR products were analyzed by electrophoresis. A conventional PCR was carried out as nested PCR to verify the gene amplicon sizes. PCR-RFLP patterns, obtained with Hinc II and Pvu II enzyme analysis showed the differences to distinguish aflatoxin-producing fungi. However, they are not quantitative and need a separation of the products on gel and their visualization under UV light. On the other hand, qPCR facilitates the monitoring of the reaction as it progresses. It does not require post-PCR handling, which reduces the risk of cross-contamination and handling errors. It results in a much faster throughout. We found that the optimal primer annealing temperature was $65^{\circ}C$. The optimized template and primer concentration were $1.5{\mu}L\;(50ng/{\mu}L)$ and $3{\mu}L\;(10{\mu}M/{\mu}L)$ respectively. SYBR Green qPCR of four genes demonstrated amplification curves and melting peaks for tub1, afIM, afIR, and afID genes are at $88.0^{\circ}C$, $87.5^{\circ}C$, $83.5^{\circ}C$, and $89.5^{\circ}C$ respectively. Consequently, it was found that the four primers had elevated annealing temperatures, nevertheless it is desirable since it enhances the DNA binding specificity of the dye. New qPCR protocol could be employed for the determination of aflatoxin content in feedstuff samples.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.260-267
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• 2014

To evaluate microbiological and aflatoxin safety on traditional dried persimmon, a total of 315 samples were collected from 105 farms. The collected samples were assessed on aflatoxin and microorganisms (Aerobic plate count, coliform count, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus). The the APC of sliced dried persimmon, dried persimmon, and semi dried persimmon were $3.93{\pm}0.96$, $2.12{\pm}0.93$, and $1.50{\pm}1.08{\log}\;CFU/g$, respectively. S. aureus was detected in 40.0% of sliced dried persimmon, 29.5% of dried persimmon, and 23.5% of semi dried persimmon. E. coli recovered from dried persimmon and semi dried persimmon was 6.6%, and 2.9%, respectively. However, E. coli O157:H7, Salmonella spp., and L. monocytogenes were not detected. According to the result of aflatoxin by ELISA and UPLC, aflatoxin was not detected in any sample. These data suggested that safety management system should be introduce to the farms producing traditional dried persimmon to enhance the safety of traditional dried persimmon.

• YAKHAK HOEJI
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• v.35 no.4
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• pp.253-257
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• 1991

The anti-mutagenic effect of Orostachys japonicus (OJ) toward aflatoxin (AFB$_{1}$) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the Salmonella assay system was studied. The methanol extract of OJ inhibited the mutagenicity induced by AFB$_{1}$ about 97% when 5% of the extract added to the system. Butanol fraction from the methanol extract was the most effective against AFB$_{1}$. However, other fractions of hexane, chloroform, and ethylacetate also showed considerable antimutagenic activity against AFB$_{1}$. Several identified compounds from the fractions of OJ exhibited anti-mutagenic effect. $\beta$-Sitosterol, astragalin and kaempferol-3-rhamnosyl-7-glucoside were selected from the compounds, and these compounds inhibited the mutagenicity dose-dependently. These 3 compounds also decreased the mutagenicity induced by MNNG. From these results, it is suggested that the major compounds such as triterpene, sterol and flavonoid in the OJ were responsible for the inhibition of the AFB$_{1}$ and MNNG-induced mutagenicities.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3371-3376
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• 2015

Pigmented rice bran has been suggested to be a valuable source of beneficial phytochemicals. We investigated genotoxic and anti-genotoxic effects of purple rice bran extract (PRBE) in rats using a liver micronucleus assay. Purple rice bran was extracted with methanol, obtaining large amounts of phenolic compounds, including anthocyanins and small amounts of gamma-oryzanol. The experimental protocols were divided into two sets. Male rats were divided into three groups. Group 1 was a negative control, while Groups 2 and 3 were fed with 100 and 500 mg/kg bw of PRBE, respectively, for 28 days. PRBE had no effect on micronucleus formation or xenobiotic metabolizing enzymes in rat liver. Experiments concerning the effect of PRBE on $AFB_1$ showed that PRBE significantly lessened the amount of micronucleated hepatocytes in $AFB_1$ treated rats. Furthermore, it modulated metabolic activation of $AFB_1$ metabolism in the liver by suppressing activity and protein expression of CYP1A2, CYP3A and CYP 450 reductase, and enhancing phase II enzymes including GST and UGT. Overall, purple rice bran extract was not genotoxic in rats. It exhibited anti-genotoxicity by modulation some xenobiotic enzymes active in $AFB_1$ metabolism.

• Mycobiology
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• v.35 no.2
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• pp.76-81
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• 2007

Lactobacillus casei KC-324 was tested for its ability to inhibit aflatoxin production and mycelial growth of Aspergillus flavus ATCC 15517 in liquid culture. flatoxin $B_{1}$ biosynthesis and mycelial growth were inhibited in both simultaneous culture and individual antagonism assays, suggesting that the inhibitory activity was due to extracellular metabolites. produced in cell-free supernatant fluids of the cultured broth of L. casei KC-324. In cell-free supernatant fluids of all media tested, deMan, Rogosa and Sharpe broth, potato dextrose broth, and Czapek-Dox broth+1% yeast extract showed higher antiaflatoxigenic activity. In these case, fungal growths, however, was not affected as measured by mycelial dry weight. The antiaflatoxigenic metabolites from L. casei KC-324 were produced over wide range of temperatures between $25^{\circ}C$ and $37^{\circ}C$. However, these metabolites were not thermostable since the inhibitory activity of the supernatant was inactivated within 30 minutes at $100^{\circ}C$ and $121^{\circ}C$. The inhibitory activity was not influenced by changing pH of supernatant between 4 and 10. However, the antiaflatoxigenic activity was slightly reduced at pH 10.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.274-279
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• 2001

Generally, non-aflatoxigenic fungi, such as Aspergillus oryzae, and Aspergillus are main microflora in Korean traditional fermented foods including Meju and soybean paste, but sometimes, Aspergillus flavus and Aspergillus parasiticus can be contaminated and accumulated aflatoxins during fermentation and storage. So the screening of aflatoxigenic strains in fermented traditional food is very important to improve the sanitary quality of those foods. In this work, we screened aflatoxin producing fungi from commercial Meju and soybean paste in Western Gyeongnam by immunoassay. Samples were randomly purchased from market of the commercial Meju(10 EA) and soybean paste(20 EA) in nine areas of Western Gyeongnam. Of the samples collected,24 strains and 22 strains of Aspergillus sp. were isolated from Meju and soybean paste, respectively. The isolated strains were cultured on SLS media at $25^{\circ}C$ for 15 days. The cultured broth were extracted with ethyl acetate and were analysed to determine aflatoxin B$_1$(AFB$_1$) by direct competitive ELISA(DC-ELISA). Six strains(25%) isolated from Meju, and 2 strains(9%) isolated from saybean paste, were confined as aflatoxin producing strains. The average range of aflatoxin productivity of isolates from Meju was 54.6 $\pm$ 38.7 ng/ml and that from soybean paste was 11.1 $\pm$ 8.6 ng/ml, respectively. Among them, isolated strain No. M-5-4 produced a high level of AFBl and showed 98.26 ng/ml of AFB$_1$. Every isolates were also re-confined their AFB$_1$productivity by thin layer chromatography(TLC). The TLC results also showed same trend as DC-ELISA results. As the above results, the screening of hazard mycotoxigenic fungi from traditional fermented foods should be necessary for the safety and the application of HACCP system in the food manufactory in Korea.

• Korean Journal of Poultry Science
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• v.17 no.4
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• pp.296-302
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• 1990

This study was conducted to investigate the interaction of aflatoxin B$_1$($AFB_1$) and vitamin D$_3$($VD_3$) in broiler chicks. The 336 broiler chicks(Hubbard line) of equally mixed sex were allocated to triplicate 8(2$\times$4 factorial) treatment groups. The 0 or 1ppm of AFB$_1$and 0, 500, 1,000 or 1,500IU/kg of VD$_3$ were supplemented to the basal diet Fourteen broilers of equally mixed sex were allocated to each replica and 24 groups were arranged in a randomized block design After 3 weeks of feeding the metatarsus were collected from the right and left legs of 4 chicks (2 for each sex) per group. The bone ash and minerals were measured. 1. In respect to the fresh weight of metatarsus bone no significant difference was found between 0 and 1ppm $AFB_1$ treatments, however, decreasing trend was recognized when fed increasing level of $VD_3$(P＜.01). 2. The ash content in non－fat dry metatarsus bone decreased when fed 1ppm $AFB_1$(P＜.01). However, that increased according to the increasing amount of $VD_3$(P＜.01). Although there was no interaction between $AFB_1$ and $VD_3$ it was shown that the 1500IU/kg of $VD_3$ was neccessary to cover the decrease in ash content of metatarsus. when fed 1ppm of $AFB_1$. 3. The Ca contents in metatarsus were not influenced by feeding $AFB_1$ but an increasing trend was verified by feeding increasing levels of $VD_3$(P＜.05). 4. The P content decreased as $AFB_1$ was fed(P＜.01), while no response was found when fed'different levels of $VD_3$ 5. The Cu content decreased when fed $AFB_1$(P＜.05). 6. The Na, Mg, K, Zn, Fe and Mn contents were not affected by feeding $AFB_1$ and /or $VD_3$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.1
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• pp.1-9
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• 1987

Large amount of aflatoxin $B_1(AFB_1)$ is disappeared in the presence of L-ascorbic acid(AA) in buffer solution at pH values from 1 to 7 during 5 days of Incubation at $37^{\circ}C$. $AFB_1$ was quite stable at pH's between 5 and 7 when AA was absent(control), however, $50{\sim}60%$ of APB, was degraded in its presence after 5 days. The rate of disappearance of $AFB_1$ increased with a decreasing of pH in the presence of AA, even though $AFB_1$ in the control degraded increasingly with the decrease in $pH(pH{\leq}4)$. The level of $AFB_1$, decreased as the reaction temperature increased when $AFB_1$ reacted with AA. The aflatoxin could not be detected at all after 3 days when the reaction occurred at $60^{\circ}C$, while the aflatoxin was stable at $5^{\circ}C$ thoughout the reaction period. $90{\sim}96%$ of $AFB_1$ was found to be degraded in a far when $AFB_1$ reacted with AA plus different concentrations of $CuSO_4{\cdot}5H_{2}O$, showing remarkably faster rate than the control; however, different concentrations of L-cysteine instead of $CuSO_4\;5H_{2}O$ protected the degradation of aflatoxin and no $AFB_1$ was degraded for a day and resulted in less $AFB_1$ disappeared than the control. The degradation of $AFB_1$ was dependent on AA concentration and the rate of disappearance as the concentration of AA decrease, but $AFB_1$ concentration did not influence the rate. The product formed when $AFB_1$ reacted with AA was identified to $AFB_{2a}$ by using HPLC chromatographic examinations, and by UV spectrum of $AFB_1$ reacted with AA. The disappearance of $AFB_1$ was correlated well in the appearance of $AFB_2a$. From the results, the degradation of $AFB_1$ in the presence of AA is probably due to one or more of the oxidative products of AA which was produced during the AA oxidation.