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Sample records for afb1 afb2 afg1

  1. Spectra analysis of coating antigen: A possible explanation for difference in anti-AFB1 polyclonal antibody sensitivity

    NASA Astrophysics Data System (ADS)

    Ye, Yang; Liu, Aiping; Wang, Xiaohong; Chen, Fusheng

    2016-10-01

    For the detection of small hapten molecules, indirect competitive enzyme-linked immunosorbent assay (icELISA) is a preferred method. However, diverse coating antigen might bring different antiserum titer and sensitivity for the identical antiserum. In the present study, four AFB1-protein (aflatoxin B1-carrier protein) conjugates were prepared by activated ester method (AFB1O-BSA/AFB1O-OVA) and mannich method (AFB1-cBSA/AFB1-cOVA), and then applied as coating antigen for titer and sensitivity detection of the identical antiserum obtained from rabbit immunized by AFB1-KLH. Afterwards, the ultraviolet-visible, fluorescence and far-ultraviolet circular dichroism (far-UV CD) spectra were recorded for understanding the difference in titer and sensitivity obtained. Results revealed that AFB1O-BSA/AFB1O-OVA showed a strong intrinsic fluorescence band centered at 450 nm that originated from the emission of AFB1, which differed from AFB1-cBSA/AFB1-cOVA, while the decrease of α-helical and increase of β-sheet in AFB1-cBSA was the most remarkable. This indicated that the better sensitivity obtained by using AFB1O-BSA as coating antigen might be caused by its extended structure, because such structure affect the binding between AFB1 and antibody. The study might offer structural information for understanding the titer and sensitivity difference caused by coating antigen.

  2. Natural co-occurrence of ochratoxin A, ochratoxin B and aflatoxins in Sicilian red wines.

    PubMed

    Di Stefano, Vita; Avellone, Giuseppe; Pitonzo, Rosa; Capocchiano, Valentina Giusi; Mazza, Alessia; Cicero, Nicola; Dugo, Giacomo

    2015-01-01

    The natural occurrence of ochratoxin A, ochratoxin B, aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 (OTA, OTB, AFB1, AFB2, AFG1, AFG2) in red wines was investigated by HPLC/FLD after immunoaffinity column clean-up in 57 market samples produced in Sicily (Italy). The results showed a very low incidence of these mycotoxins in analysed samples, confirming the high degree of quality and safety of Sicilian red wines. The results indicated 71.9% and 64.9% positive samples for OTA and OTB respectively, with an average level of 0.13 μg l(-1), well below the European maximum permitted levels (MLs). The aflatoxin most frequently detected in the samples was AFG1, present in 57.9% of samples, while the other aflatoxins were rarely present. Recovery experiments were carried out on eight mycotoxin-free red wines spiked with OTA, OTB, AFB1, AFB2, AFG1 and AFG2 at two different levels. The limits of detection (LODs) in wines were 0.02 µg l(-1) for OTA, 0.04 µg l(-1) for OTB, 0.03 µg l(-1) for AFG1, AFG2 and AFB2, and 0.05 µg l(-1) for AFB1. A good correlation was found, with good performances in term of precision for the method.

  3. Incidence and Level of Aflatoxins Contamination in Medicinal Plants in Korea

    PubMed Central

    Lee, Sung Deuk; Yu, In Sil; Jung, Kweon

    2014-01-01

    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 0.1~404.7 µg/kg for AFB1, 0.1~10.0 µg/kg for AFB2, 0.1~635.3 µg/kg for AFG1, 0.1~182.5 µg/kg for AFG2, and 0.1~1,043.9 µg/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 µg/kg established by the Korean standard for AFB1 and total aflatoxins (the sum of AFB1, AFB2, AFG1 and AFG2), respectively. PMID:25606005

  4. Uncommon occurrence ratios of aflatoxin B1, B 2, G 1, and G 2 in maize and groundnuts from Malawi.

    PubMed

    Matumba, Limbikani; Sulyok, Michael; Njoroge, Samuel M C; Njumbe Ediage, Emmanuel; Van Poucke, Christof; De Saeger, Sarah; Krska, Rudolf

    2015-02-01

    We report an unusual aflatoxin profile in maize and groundnuts from Malawi, with aflatoxin G1 found routinely at equal or even higher levels than aflatoxin B1. Aflatoxin B1 (AFB1) ratio in a contaminated sample is generally greater than 50% of total aflatoxin (sum of aflatoxin B1, B2, G1, and G2). In Malawi, the aflatoxin occurrence ratios were determined by examining LC-MS/MS and HPLC fluorescence detection (FLD) data of 156 naturally contaminated raw maize and 80 groundnut samples collected in 2011 and 2012. Results showed that natural aflatoxin occurrence ratio differed. In 47% of the samples, the concentration of AFG1 was higher than that of AFB1. The mean concentration percentages of AFB1/AFB2/AFG1/AFG2 in reference to total aflatoxins were found to be 47:5:43:5%, respectively. The AFG1 and AFB1 50/50 trend was observed in maize and groundnuts and was consistent for samples collected in both years. If the AFB1 measurement was used to check compliance of total aflatoxin regulatory limit set at 10, 20, 100, and 200 μg/kg with an assumption that AFB1≥50% of the total aflatoxin content, 8, 13, 24, and 26% false negative rates would have occurred respectively. It is therefore important for legislation to consider total aflatoxins rather than AFB1 alone.

  5. Antagonistic effects of Satureja hortensis essential oil against AFB1 on human lymphocytes in vitro.

    PubMed

    Ceker, S; Agar, G; Alpsoy, L; Nardemir, G; Kizil, H E

    2014-01-01

    Satureja hortensis L. (Lamiaceae) has been used as a folk remedy to treat various such as cramps, muscle pains, nausea, indigestion, diarrhea, and infectious diseases. In this study, the antagonistic effects of essential oil of S. hortensis (SHE) were studied against aflatoxin B1 (AFB1) in human lymphocytes in vitro. The analysis of the essential oil was performed by using Gas chromatography-mass spectrometry (GC-MS). Anti-genotoxic effects of the SHEs was evaluated using sister chromatid exchange (SCE), micronuclei (MN) tests against AFB1. Also level of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities used to determine the anti-oxidative effects of the SHEs. This result showed AFB1 (5 microM) increased the frequencies of SCE, MN and the level of MDA. AFB1 at the same concentration decreased the activities of SOD and GPx. However, different concentrations of SHE with AFB1 decreased the frequency of SCE and MN and level of MDA and also increased the activities of SOD and GPx significantly. Especially, the 1.0, 1.5, 2.0 microL dose of SHE are more effective than other doses. The results of this experiment have clearly shown that SHE has strong antioxidative and antigenotoxic effects, these biological activities of SHEs can be due to its component.

  6. The role of NAD(+)-dependent isocitrate dehydrogenase 3 subunit α in AFB1 induced liver lesion.

    PubMed

    Yang, Chi; Fan, Jue; Zhuang, Zhenhong; Fang, Yi; Zhang, Yanfeng; Wang, Shihua

    2014-01-30

    Aflatoxin B1 (AFB1) is a potent hepatocarcinogen that causes carcinogenesis in many animal species. In previous study, we found that isocitrate dehydrogenase 3α subunit (IDH3α) was upregulated in AFB1-induced carcinogenesis process. In this study, the sequences of IDH3α from various species were compared and the protein expression levels in different organs were examined, and the results showed that IDH3α was a widely distributed protein and shared highly conserved sequence in various species. In the same time, IDH3α was demonstrated to accumulate in a dose-dependent manner induced by AFB1 in cells, and was also up-regulated in the process of AFB1-induced liver lesion. Similar results were observed when H2O2 was used to replace AFB1. Over-expression of IDH3α increased the phosphorylation level of Akt (Protein kinase B) and neutralized the cellular toxicity induced by AFB1 or H2O2 and apoptosis induced by AFB1, while the reduced expression of IDH3α by siRNA decreased the phosphorylation, indicating that IDH3α played important roles in oxidative stress-induced PI3K/Akt pathway. Overall, the results suggested that AFB1 treatment could increase the expression of IDH3α, and the activated PI3K/Akt pathway by IDH3α eventually neutralized the apoptosis induced by AFB1.

  7. The molecular mechanism of G2/M cell cycle arrest induced by AFB1 in the jejunum

    PubMed Central

    Yin, Heng; Jiang, Min; Peng, Xi; Cui, Hengmin; Zhou, Yi; He, Min; Zuo, Zhicai; Ouyang, Ping; Fan, Junde; Fang, Jing

    2016-01-01

    Aflatoxin B1 (AFB1) has potent hepatotoxic, carcinogenic, genotoxic, immunotoxic and other adverse effects in human and animals. The aim of this study was to investigate the molecular mechanism of G2/M cell cycle arrest induced by AFB1 in the jejunum of broilers. Broilers, as experimental animals, were fed 0.6 mg/kg AFB1 diet for 3 weeks. Our results showed that AFB1 reduced the jejunal villus height, villus height/crypt ratio and caused G2/M cell cycle arrest. The G2/M cell cycle was accompanied by the increase of ataxia telangiectasia mutated (ATM), p53, Chk2, p21 protein and mRNA expression, and the decrease of Mdm2, cdc25C, cdc2, cyclin B and proliferating cell nuclear antigen protein and mRNA expression. In conclusion, AFB1 blocked G2/M cell cycle by ATM pathway in the jejunum of broilers. PMID:27232757

  8. Microbial Contamination of Seven Major Weaning Foods in Nigeria

    PubMed Central

    Ibeh, I. Nnanna

    2011-01-01

    Five million children aged less than five years die annually due to diarrhoea. The aim of the study was to identify some possible contributing factors for persistent diarrhoea. Seven weaning foods, including a locally-made food, were evaluated by estimating the microbial load using the most probable number method and aflatoxin levels (AFM1, AFG1, AFG2, and AFB2) by immunoaffinity column extraction and high-performance liquid chromatography (HPLC) with detection of fluorescence. The results showed that the locally-made weaning food had the highest microbial count (2,000 cfu/g) and faecal streptococcal count (25 cfu/g). Moulds isolated were mainly Aspergillus niger, A. flavus, A. glaucus, Cladosporium sp., and Penicillium sp. The home-made weaning food recorded the highest fungal count (6,500 cfu/g). AFM1 of the weaning foods was 4.6-530 ng/mL. One weaning food had AFB1 level of 4,806 ng/g. Aflatoxin metabolites, apart from AFM1 and AFB1 present in the weaning foods, were AFG1 and AFG2. There were low microbial counts in commercial weaning foods but had high levels of aflatoxins (AFM1, AFG1, AFG2, AFB1, and AFB2). Growth and development of the infant is rapid, and it is, thus, possible that exposure to aflatoxins in weaning foods might have significant health effects. PMID:21957681

  9. Determination of the aflatoxin AFB1 from corn by direct analysis in real time-mass spectrometry (DART-MS).

    PubMed

    Busman, Mark; Liu, Jihong; Zhong, Hongjian; Bobell, John R; Maragos, Chris M

    2014-01-01

    Direct analysis in real time (DART) ionisation coupled to a high-resolution mass spectrometer (MS) was used for screening of aflatoxins from a variety of surfaces and the rapid quantitative analysis of a common form of aflatoxin, AFB1, extracted from corn. Sample preparation procedure and instrument parameter settings were optimised to obtain sensitive and accurate determination of aflatoxin AFB1. 84:16 acetonitrile water extracts of corn were analysed by DART-MS. The lowest calibration level (LCL) for aflatoxin AFB1 was 4 μg kg⁻¹. Quantitative analysis was performed with the use of matrix-matched standards employing the ¹³C-labelled internal standard for AFB1. DART-MS of spiked corn extracts gave linear response in the range 4-1000 μg kg⁻¹. Good recoveries (94-110%) and repeatabilities (RSD = 0.7-6.9%) were obtained at spiking levels of 20 and 100 μg kg⁻¹ with the use of an isotope dilution technique. Trueness of data obtained for AFB1 in maize by DART-MS was demonstrated by analysis of corn certified reference materials.

  10. XPD codon 312 and 751 polymorphisms, and AFB1 exposure, and hepatocellular carcinoma risk

    PubMed Central

    2009-01-01

    Background Genetic polymorphisms in DNA repair genes may influence individual variation in DNA repair capacity, which may be associated with risk of hepatocellular carcinoma (HCC) related to the exposure of aflatoxin B1 (AFB1). In this study, we have focused on the polymorphisms of xeroderma pigmentosum complementation group D (XPD) codon 312 and 751 (namely Asp312Asn and Lys751Gln), involved in nucleotide excision repair. Methods We conducted a case-control study including 618 HCC cases and 712 controls to evaluate the associations between these two polymorphisms and HCC risk for Guangxi population by means of TaqMan-PCR and PCR-RFLP analysis. Results We found that individuals featuring the XPD genotypes with codon 751 Gln alleles (namely XPD-LG or XPD-GG) were related to an elevated risk of HCC compared to those with the homozygote of XPD codon 751 Lys alleles [namely XPD-LL, adjusted odds ratios (ORs) were 1.75 and 2.47; 95% confidence interval (CIs) were 1.30-2.37 and 1.62-3.76, respectively]. A gender-specific role was evident that showed an higher risk for women (adjusted OR was 8.58 for XPD-GG) than for men (adjusted OR = 2.90 for XPD-GG). Interestingly, the interactive effects of this polymorphism and AFB1-exposure information showed the codon 751 Gln alleles increase the risk of HCC for individuals facing longer exposure years (Pinteraction = 0.011, OR = 0.85). For example, long-exposure-years (> 48 years) individuals who carried XDP-GG had an adjusted OR of 470.25, whereas long-exposure-years people with XDP-LL were at lower risk (adjusted OR = 149.12). However, we did not find that XPD codon 312 polymorphism was significantly associated with HCC risk. Conclusion These findings suggest that XPD Lys751Gln polymorphism is an important modulator of AFB1 related-HCC development in Guangxi population. PMID:19919686

  11. Production of M-/GM-group aflatoxins catalyzed by the OrdA enzyme in aflatoxin biosynthesis.

    PubMed

    Yabe, Kimiko; Chihaya, Naomi; Hatabayashi, Hidemi; Kito, Masako; Hoshino, Sachiko; Zeng, Hongmei; Cai, Jingjing; Nakajima, Hiromitsu

    2012-09-01

    Aspergillus parasiticus produces the minor aflatoxins M(1) (AFM(1)), M(2) (AFM(2)), GM(1) (AFGM(1)), and GM(2) (AFGM(2)), as well as the major aflatoxins B(1) (AFB(1)), B(2) (AFB(2)), G(1) (AFG(1)), and G(2) (AFG(2)). Feeding of A. parasiticus with aspertoxin (12c-hydroxyOMST) caused AFM(1) and AFGM(1), and cell-free experiments using the microsomal fraction of A. parasiticus and aspertoxin caused production of AFM(1), indicating that aspertoxin is a precursor of AFM(1) and AFGM(1). Feeding of the same fungus with O-methylsterigmatocystin (OMST) caused AFM(1) and AFGM(1) together with AFB(1) and AFG(1); feeding with dihydroOMST (DHOMST) caused AFM(2) and AFGM(2) together with AFB(2) and AFG(2). Incubation of either the microsomal fraction or OrdA enzyme-expressing yeast with OMST caused production of aspertoxin together with AFM(1) and AFB(1). These results demonstrated that the OrdA enzyme catalyzes both 12c-hydroxylation reaction from OMST to aspertoxin and the successive reaction from aspertoxin to AFM(1). In contrast, feeding of the fungus with AFB(1) did not produce any AFM(1), demonstrating that M-/GM-aflatoxins are not produced from B-/G-aflatoxins. Furthermore, AFM(1) together with AFB(1) and AFG(1) was also produced from 11-hydroxyOMST (HOMST) in feeding experiment of A. parasiticus, whereas no aflatoxins were produced when used the ordA deletion mutant. These results demonstrated that OrdA enzyme can also catalyze 12c-hydroxylation of HOMST to produce 11-hydroxyaspertoxin, which serves as a precursor for the production of AFM(1) and AFGM(1). The same pathway may work for the production of AFM(2) and AFGM(2) from DHOMST and dihydroHOMST through the formation of dihydroaspertoxin and dihydro-11-hydroxyaspertoxin, respectively.

  12. A probabilistic modeling approach to assess human inhalation exposure risks to airborne aflatoxin B 1 (AFB 1)

    NASA Astrophysics Data System (ADS)

    Liao, Chung-Min; Chen, Szu-Chieh

    To assess how the human lung exposure to airborne aflatoxin B 1 (AFB 1) during on-farm activities including swine feeding, storage bin cleaning, corn harvest, and grain elevator loading/unloading, we present a probabilistic risk model, appraised with empirical data. The model integrates probabilistic exposure profiles from a compartmental lung model with the reconstructed dose-response relationships based on an empirical three-parameter Hill equation model, describing AFB 1 cytotoxicity for inhibition response in human bronchial epithelial cells, to quantitatively estimate the inhalation exposure risks. The risk assessment results implicate that exposure to airborne AFB 1 may pose no significance to corn harvest and grain elevator loading/unloading activities, yet a relatively high risk for swine feeding and storage bin cleaning. Applying a joint probability function method based on exceedence profiles, we estimate that a potential high risk for the bronchial region (inhibition=56.69% with 95% confidence interval (CI): 35.05-72.87%) and bronchiolar region (inhibition=44.93% with 95% CI: 21.61 - 66.78%) is alarming during swine feeding activity. We parameterized the proposed predictive model that should encourage a risk-management framework for discussion of carcinogenic risk in occupational settings where inhalation of AFB 1-contaminated dust occurs.

  13. Detection of aflatoxin B1 (AFB1) in individual maize kernels using short wave infrared (SWIR) hyperspectral imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Short wave infrared hyperspectral imaging (SWIR) (1000-2500 nm) was used to detect aflatoxin B1 (AFB1) in individual maize kernels. A total of 120 kernels of four varieties (or 30 kernels per variety) that had been artificially inoculated with a toxigenic strain of Aspergillus flavus and harvested f...

  14. Determination of the aflatoxin AFB1 from corn by direct analysis in real time-mass spectrometry (DART-MS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Direct analysis in real time (DART) ionization coupled to a high resolution mass spectrometer (MS) was used for screening of aflatoxins from a variety of surfaces and the rapid quantitative analysis of a common form of aflatoxin, AFB1, extracted from corn. Sample preparation procedure and instrument...

  15. Monoclonal IgA Antibodies for Aflatoxin Immunoassays

    PubMed Central

    Ertekin, Özlem; Pirinçci, Şerife Şeyda; Öztürk, Selma

    2016-01-01

    Antibody based techniques are widely used for the detection of aflatoxins which are potent toxins with a high rate of occurrence in many crops. We developed a murine monoclonal antibody of immunoglobulin A (IgA) isotype with a strong binding affinity to aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2) and aflatoxin M1 (AFM1). The antibody was effectively used in immunoaffinity column (IAC) and ELISA kit development. The performance of the IACs was compatible with AOAC performance standards for affinity columns (Test Method: AOAC 991.31). The total binding capacity of the IACs containing our antibody was 111 ng, 70 ng, 114 ng and 73 ng for AFB1, AFB2, and AFG1 andAFG2, respectively. Furthermore, the recovery rates of 5 ng of each AF derivative loaded to the IACs were determined as 104.9%, 82.4%, 85.5% and 70.7% for AFB1, AFB2, AFG1 and AFG2, respectively. As for the ELISA kit developed using non-oriented, purified IgA antibody, we observed a detection range of 2–50 µg/L with 40 min total test time. The monoclonal antibody developed in this research is hitherto the first presentation of quadruple antigen binding IgA monoclonal antibodies in mycotoxin analysis and also the first study of their utilization in ELISA and IACs. IgA antibodies are valuable alternatives for immunoassay development, in terms of both sensitivity and ease of preparation, since they do not require any orientation effort. PMID:27187470

  16. Selenomethionine alleviates AFB1-induced damage in primary chicken hepatocytes by inhibiting CYP450 1A5 expression via upregulated SelW expression.

    PubMed

    Chen, Xingxiang; Che, Chaoping; Korolchuk, Viktor I; Gan, Fang; Pan, Cuiling; Huang, Kehe

    2017-03-13

    This study aims to evaluate the protective effects of selenomethionine (SeMet) on Aflatoxin B1 (AFB1)-induced hepatotoxicity in primary chicken hepatocytes. Cell viability and lactic dehydrogenase activity assays revealed the dose-dependency of AFB1 toxicity to chicken hepatocytes. AFB1 concentrations above 0.05 μg/mL significantly reduced glutathione and total superoxide dismutase levels, as well as increased malondialdehyde concentration and cytochrome P450 enzyme 1A5 (CYP450 1A5) mRNA levels (P < 0.05). AFB1, however, did not affect CYP450 3A37 mRNA levels. Supplementation with 2 μM SeMet protected against AFB1-induced changes and significantly increased selenoprotein W (SelW) mRNA levels (P < 0.05). Additionally, SelW knockdown attenuated the protective effect of SeMet on AFB1-induced damage and significantly increased CYP450 1A5 expression (P < 0.05). Therefore, SeMet alleviates AFB1-induced damage in primary chicken hepatocytes by improving SelW expression, thus inhibiting CYP450 1A5 expression.

  17. Production of Group Specific Monoclonal Antibody to Aflatoxins and its Application to Enzyme-linked Immunosorbent Assay

    PubMed Central

    Kim, Sung-Hee; Cha, Sang-Ho; Karyn, Bischoff; Park, Sung-Won; Son, Seong-Wan

    2011-01-01

    Through the present study, we produced a monoclonal antibody against aflatoxin B1 (AFB1) using AFB1- carboxymethoxylamine BSA conjugates. One clone showing high binding ability was selected and it was applied to develop a direct competitive ELISA system. The epitope densities of AFB1-CMO against BSA and KLH were about 1 : 6 and 1 : 545, respectively. The monoclonal antibody (mAb) from cloned hybridoma cell was the IgG1 subclass with λ-type light chains. The IC50s of the monoclonal antibody developed for AFB1, AFB2, AFG1 and AFG2 were 4.36, 7.22, 6.61 and 29.41 ng/ml, respectively, based on the AFB1-KLH coated ELISA system and 15.28, 26.62, 32.75 and 56.67 ng/ml, respectively, based on the mAb coated ELISA. Cross-relativities of mAb to AFB1 for AFB2, AFG1 and AFG2 were 60.47, 65.97 and 14.83% in the AFB1-KLH coated ELISA, and 59.41, 46.66 and 26.97% in the mAb coated ELISA, respectively. Quantitative calculations for AFB1 from the AFB1-Ab ELISA and AFB1-Ag ELISA ranged from 0.25 to 25 ng/ml (R2 > 0.99) and from 1 to 100 ng/ml (R2 > 0.99), respectively. The intra- and inter-assay precision CVs were < 10% in both ELISA assay, representing good reproducibility of developed assay. Recoveries ranged from 79.18 to 91.27%, CVs ranged from 3.21 to 7.97% after spiking AFB1 at concentrations ranging from 5 to 50 ng/ml and following by extraction with 70% methanol solution in the Ab-coated ELISA. In conclusion, we produced a group specific mAb against aflatoxins and developed two direct competitive ELISAs for the detection of AFB1 in feeds based on a monoclonal antibody developed. PMID:24278561

  18. Detection of serum AFB1-lysine adduct in Malaysia and its association with liver and kidney functions.

    PubMed

    Mohd Redzwan, S; Rosita, Jamaluddin; Mohd Sokhini, A M; Nurul 'Aqilah, A R; Wang, Jia-Sheng; Kang, Min-Su; Zuraini, Ahmad

    2014-01-01

    Aflatoxin is ubiquitously found in many foodstuffs and produced by Aspergillus species of fungi. Of many aflatoxin metabolites, AFB1 is classified by the International Agency for Research on Cancer (IARC) as group one carcinogen and linked to the development of hepatocellular carcinoma (HCC). The study on molecular biomarker of aflatoxin provides a better assessment on the extent of human exposure to aflatoxin. In Malaysia, the occurrences of aflatoxin-contaminated foods have been documented, but there is a lack of data on human exposure to aflatoxin. Hence, this study investigated the occurrence of AFB1-lysine adduct in serum samples and its association with liver and kidney functions. 5ml fasting blood samples were collected from seventy-one subjects (n=71) for the measurement of AFB1-lysine adduct, albumin, total bilirubin, AST (aspartate aminotransferase), ALT (alanine transaminase), ALP (alkaline phosphatase), GGT (gamma-glutamyl transpeptidase), creatinine and BUN (blood urea nitrogen). The AFB1-lysine adduct was detected in all serum samples (100% detection rate) with a mean of 6.85±3.20pg/mg albumin (range: 1.13-18.85pg/mg albumin). Male subjects (mean: 8.03±3.41pg/mg albumin) had significantly higher adduct levels than female subjects (mean: 5.64±2.46pg/mg albumin) (p<0.01). It was noteworthy that subjects with adduct levels greater than average (>6.85pg/mg albumin) had significantly elevated level of total bilirubin (p<0.01), GGT (p<0.05) and creatinine (p<0.01). Nevertheless, only the level of total bilirubin, (r=0.347, p-value=0.003) and creatinine (r=0.318, p-value=0.007) showed significant and positive correlation with the level of AFB1-lysine adduct. This study provides a valuable insight on human exposure to aflatoxin in Malaysia. Given that aflatoxin can pose serious problem to the health, intervention strategies should be implemented to limit/reduce human exposure to aflatoxin. Besides, a study with a big sample size should be warranted in

  19. Calcium montmorillonite clay reduces AFB1 and FB1 biomarkers in rats exposed to single and co-exposures of aflatoxin and fumonisin

    PubMed Central

    Mitchell, Nicole J.; Xue, Kathy S.; Lin, Shuhan; Marroquin-Cardona, Alicia; Brown, Kristal A.; Elmore, Sarah E.; Tang, Lili; Romoser, Amelia; Gelderblom, Wentzel C. A.; Wang, Jia-Sheng; Phillips, Timothy D.

    2014-01-01

    Aflatoxins (AFs) and fumonisins (FBs) can co-contaminate foodstuffs and have been associated with hepatocellular and esophageal carcinomas in humans at high risk for exposure. One strategy to reduce exposure (and toxicity) from contaminated foodstuffs is the dietary inclusion of a montmorillonite clay (UPSN) that binds AFs and FBs in the GI tract. In this study, the binding capacity of UPSN was evaluated for AFB1, FB1 and a combination thereof in Fischer-344 rats. Rats were pre-treated with different dietary levels of UPSN (0.25 or 2%) for 1 week. Rats were gavaged with a single dose of either 0.125 mg AFB1 or 25 mg FB1/kg b.w. and a combination thereof in the presence and absence of an aqueous solution of UPSN. The kinetics of mycotoxin excretion were monitored by analyzing serum AFB1-albumin, urinary AF (AFM1), and FB1 biomarkers over a period of 72 hr. UPSN decreased AFM1 excretion by 88-97%, indicating highly effective binding. FB1 excretion was reduced, to a lesser extent, ranging between 45 to 85%. When in combination, both AFB1 and FB1 binding occurred, but capacity was decreased by almost half. In the absence of UPSN, the combined AFB1 and FB1 treatment decreased the urinary biomarkers by 67 and 45% respectively, but increased levels of AFB1-albumin, presumably by modulating its cytochrome metabolism. UPSN significantly reduced bioavailability of both AFB1 and FB1 when in combination; suggesting that it can be utilized to reduce levels below their respective thresholds for affecting adverse biological effects. PMID:24193864

  20. Label Free QCM Immunobiosensor for AFB1 Detection Using Monoclonal IgA Antibody as Recognition Element

    PubMed Central

    Ertekin, Özlem; Öztürk, Selma; Öztürk, Zafer Ziya

    2016-01-01

    This study introduces the use of an IgA isotype aflatoxin (AF) specific monoclonal antibody for the development of a highly sensitive Quartz Crystal Microbalance (QCM) immunobiosensor for the detection of AF in inhibitory immunoassay format. The higher molecular weight of IgA antibodies proved an advantage over commonly used IgG antibodies in label free immunobiosensor measurements. IgA and IgG antibodies with similar affinity for AF were used in the comparative studies. Sensor surface was prepared by covalent immobilization of AFB1, using self assembled monolayer (SAM) formed on gold coated Quartz Crystal, with 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxy succinimide (EDC/NHS) method using a diamine linker. Nonspecific binding to the surface was decreased by minimizing the duration of EDC/NHS activation. Sensor surface was chemically blocked after AF immobilization without any need for protein blocking. This protein free sensor chip endured harsh solutions with strong ionic detergent at high pH, which is required for the regeneration of the high affinity antibody-antigen interaction. According to the obtained results, the detection range with IgA antibodies was higher than IgG antibodies in QCM immunosensor developed for AFB1. PMID:27529243

  1. Aflatoxins and ochratoxin a reduction in black and white pepper by gamma radiation

    NASA Astrophysics Data System (ADS)

    Jalili, M.; Jinap, S.; Noranizan, M. A.

    2012-11-01

    Irradiation is an important means of decontamination of food commodities, especially spices. The aim of the current study was to investigate the efficacy of gamma radiation (60Co) for decontaminating ochratoxin A (OTA) and aflatoxins B1 (AFB1), B2 (AFB2), G1 (AFG1) and G2 (AFG2) residues in artificially contaminated black and white pepper samples. The moisture content of the pepper samples was set at 12% or 18%, and the applied gamma dose ranged from 5 to 30 kGy. Mycotoxin levels were determined by high-performance liquid chromatography (HPLC) after immunoaffinity column (IAC) chromatography. Both the gamma irradiation dose and moisture content showed significant effects (P<0.05) on mycotoxin reduction. The maximum toxin reductions, found at 18% moisture content and 30 kGy, were 55.2%, 50.6%, 39.2%, 47.7% and 42.9% for OTA, AFB1, AFB2, AFG1 and AFG2, respectively.

  2. Mycoflora and Co-Occurrence of Fumonisins and Aflatoxins in Freshly Harvested Corn in Different Regions of Brazil

    PubMed Central

    Rocha, Liliana O.; Nakai, Viviane K.; Braghini, Raquel; Reis, Tatiana A.; Kobashigawa, Estela; Corrêa, Benedito

    2009-01-01

    Natural mycoflora and co-occurrence of fumonisins (FB1, FB2) and aflatoxins (AFB1, AFB2, AFG1 and AFG2) in freshly harvested corn grain samples from four regions of Brazil were investigated. Fusarium verticillioides was predominant in all samples. Analysis of fumonisins showed that 98% of the samples were contaminated with FB1 and 74.5% with FB1 + FB2, with toxin levels ranging from 0.015 to 9.67 μg/g for FB1 and from 0.015 to 3.16 μg/g for FB2. Twenty-one (10.5%) samples were contaminated with AFB1, seven (3.5%) with AFB2 and only one (0.5%) with AFG1 and AFG2 Co-contamination with aflatoxins and fumonisins was observed in 7% of the samples. The highest contamination of fumonisins and aflatoxins was observed in Nova Odessa (SP) and Várzea Grande (MT), respectively. The lowest contamination of these mycotoxins was found in Várzea Grande and Nova Odessa, respectively. PMID:20087478

  3. Simultaneous detection of multiple mycotoxins in broiler feeds using a liquid chromatography tandem-mass spectrometry.

    PubMed

    Kongkapan, Jutamart; Poapolathep, Saranya; Isariyodom, Supaporn; Kumagai, Susumu; Poapolathep, Amnart

    2016-02-01

    Mycotoxins are secondary fungal metabolites that are typically present in grain and feed ingredients used for animal feeds. An analytical method using LC-ESI-MS/MS was developed to quantify nine mycotoxins, consisting of aflatoxin B1 (AFB1), AFB2, AFG1, AFG2, T-2 toxin, deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA) and ochratoxin A (OTA) in broiler feeds. In total, 100 samples of broiler feeds were collected from poultry farms in Central Thailand. The survey found that AFB1 and ZEA were the most prevalent mycotoxins in the feed samples at percentages of 93% and 63%, respectively. The limit of detections (LODs) of investigated mycotoxins was 0.20-0.78 ng/g. AFB2, DON, AFG1, NIV and T-2 toxin were also detectable at low contamination levels with percentages of 20%, 9%, 7%, 5% and 1%, respectively, whereas OTA and AFG2 were not detected in any of the feed samples. These results suggest that there is a very low level of risk of the exposure to mycotoxins in feeds obtained from broiler farms in Central Thailand.

  4. Aflatoxins, hydroxylated metabolites, and aflatoxicol from breast muscle of laying hens.

    PubMed

    Díaz-Zaragoza, M; Carvajal-Moreno, M; Méndez-Ramírez, I; Chilpa-Galván, N C; Avila-González, E; Flores-Ortiz, C M

    2014-12-01

    Aflatoxins (AF) are toxic fungal secondary metabolites that are pathological to animals and humans. This study identified and quantified AF (AFB(1), AFB(2), AFG(1), AFG(2)) and their hydroxylated metabolites (AFM(1), AFM(2), AFP(1)) and aflatoxicol (AFL) from laying hen breast muscles. Aflatoxins pass from cereal feed to the laying hen tissues, causing economic losses, and from there to humans. To detect the passage of AF from feed to hen breast muscle tissues, an experiment that included 25 Hy-Line W36 121-wk-old hens was performed for 8 d. Hens in individual cages were distributed into 3 groups: a control group, with feed free of AFB(1), and 2 experimental groups, with feed spiked with 2 AFB(1) dosages: 30 µg·kg(-1) (low) or 500 µg·kg(-1) (high). The daily feed consumption per hen was recorded and afterward hens were euthanized and breast muscles were collected, weighed, and dried individually. Aflatoxins were extracted by 2 chemical methods and quantified by HPLC. Both methods were validated by lineality (calibration curves), recovery percentage (>80%), limit of detection, and limit of quantification. The AF (µg·kg(-1)) averages recovered in control breast muscles were as follows: AFB(1) (18); AFG(1), AFM(2), and AFL (0); AFG(2) (1.3); AFM(1) (52), and AFP1 (79). Hens fed with feed spiked with 30 µg·kg(-1) of AFB(1) had AFG(1) (16); AFG(2) (72); AFM(1) (0); AFM(2) (18); AFP(1) (145); and AFL (5 µg·kg(-1)). Hens with feed spiked with 500 µg·kg(-1) of AFB(1) had AFG(1) (512); AFG(2) (7); AFM(1) (4,775); AFM(2) (0); AFP(1) (661); and AFL (21 µg·kg(-1)). The best AF extraction method was Qian and Yang's method, modified by adding additional AF from both Supelclean LC18 SPE columns; its limit of detection (0.5 ng·mL(-1)) was lower compared with that of Koeltzow and Tanner, which was 1 ng·mL(-1).

  5. Mycobiota and Mycotoxins in Traditional Medicinal Seeds from China

    PubMed Central

    Chen, Amanda Juan; Jiao, Xiaolin; Hu, Yongjian; Lu, Xiaohong; Gao, Weiwei

    2015-01-01

    The multi-mycotoxin occurrence for internal and superficial fungi contamination were comprehensively assessed in medicinal seeds used as food or beverage. Based on a polyphasic approach using morphological characters, β-tubulin and ITS gene blast, a total of 27 species belonging to 12 genera were identified from surface-sterilized seeds. Chaetomium globosporum was most predominant (23%), followed by Microascus trigonosporus (12%) and Alternaria alternata (9%). With respect to superficial mycobiota, thirty-four species belonging to 17 genera were detected. Aspergillus niger and Penicillium polonicum were predominant (12% and 15%, respectively). Medicinal seed samples and potential toxigenic fungi were tested for ochratoxin A (OTA) and aflatoxins (AFB1, AFB2, AFG1, AFG2) using UPLC-MS/MS. Platycladi seeds were contaminated with AFB1 (52.0 µg/kg) and tangerine seed was contaminated with OTA (92.3 µg/kg). Subsequent analysis indicated that one A. flavus strain isolated from platycladi seed was able to synthesize AFB1 (102.0 µg/kg) and AFB2 (15.3 µg/kg). Two P. polonicum strains isolated from tangerine and lychee seeds were able to synthesize OTA (4.1 µg/kg and 14.8 µg/kg, respectively). These results identify potential sources of OTA and aflatoxins in medicinal seeds and allude to the need to establish permitted limits for these mycotoxins in these seeds that are commonly consumed by humans. PMID:26404373

  6. Mycobiota and Mycotoxins in Traditional Medicinal Seeds from China.

    PubMed

    Chen, Amanda Juan; Jiao, Xiaolin; Hu, Yongjian; Lu, Xiaohong; Gao, Weiwei

    2015-09-24

    The multi-mycotoxin occurrence for internal and superficial fungi contamination were comprehensively assessed in medicinal seeds used as food or beverage. Based on a polyphasic approach using morphological characters, β-tubulin and ITS gene blast, a total of 27 species belonging to 12 genera were identified from surface-sterilized seeds. Chaetomium globosporum was most predominant (23%), followed by Microascus trigonosporus (12%) and Alternaria alternata (9%). With respect to superficial mycobiota, thirty-four species belonging to 17 genera were detected. Aspergillus niger and Penicillium polonicum were predominant (12% and 15%, respectively). Medicinal seed samples and potential toxigenic fungi were tested for ochratoxin A (OTA) and aflatoxins (AFB1, AFB2, AFG1, AFG2) using UPLC-MS/MS. Platycladi seeds were contaminated with AFB1 (52.0 µg/kg) and tangerine seed was contaminated with OTA (92.3 µg/kg). Subsequent analysis indicated that one A. flavus strain isolated from platycladi seed was able to synthesize AFB1 (102.0 µg/kg) and AFB2 (15.3 µg/kg). Two P. polonicum strains isolated from tangerine and lychee seeds were able to synthesize OTA (4.1 µg/kg and 14.8 µg/kg, respectively). These results identify potential sources of OTA and aflatoxins in medicinal seeds and allude to the need to establish permitted limits for these mycotoxins in these seeds that are commonly consumed by humans.

  7. [Determination of aflatoxin B1, B2, G1, G2 in armeniacae semen amarum by high-performance liquid chromatography-tandem mass spectrometry].

    PubMed

    Zheng, Run-Sheng; Xu, Hui; Wang, Wen-Li; Zhan, Ruo-Ting; Chen, Wei-Wen

    2013-10-01

    A simple, rapid and cost-effective high-performance liquid chromatography-tandem mass spectrometry (LC-MS/ MS) method was established for simultaneous determination of aflatoxins (AFB1, AFB2, AFG1, AFG2) in Armeniacae Semen Amarum and the application was performance in 11 samples collected from different markets, medical stores and hospitals. The sample was extracted with 84% acetonitrile/water and 250 microL extraction was directly injected into a LC-MS/MS system without further purification procedure after being redissolved with methanol. The LC separation was performed on a C18 column with a linear gradient elution program of 4 mmol x L(-1) NH4 Ac-0.1% formic acid solution and menthol as the mobile phase. Selected reaction monitoring (SRM) was used for selective determination of the four aflatoxins on a triple quadruple mass spectrometer, which was operated in positive ionization modes. All the four aflatoxins showed a good linear relationship with r > 0.999 0, the average recoveries were between 87.88% and 102.9% and the matrix effect was ranged from 90.71% to 99.30% in low, intermediate and high levels. Furthermore, the higher recovery was obtained by the method reported in this study, comparing to the cleanup procedure with the Mycosep 226 purification column. Eleven samples collected were detected and the contamination levels of the AFB1 were between 1.590-2.340 microg x kg(-1) and the AF (B1 + B2 + G1 + G2) was ranged from 2.340 to 3.340 microg x kg(-1). In summary, the developed method was suitable to detect and screen AFB1, AFB2, AFG1, AFG2 in Armeniacae Semen Amarum.

  8. Time-course of germination, initiation of mycelium proliferation and probability of visible growth and detectable AFB1 production of an isolate of Aspergillus flavus on pistachio extract agar.

    PubMed

    Aldars-García, Laila; Sanchis, Vicente; Ramos, Antonio J; Marín, Sonia

    2017-06-01

    The aim of this work was to assess the temporal relationship among quantified germination, mycelial growth and aflatoxin B1 (AFB1) production from colonies coming from single spores, in order to find the best way to predict as accurately as possible the presence of AFB1 at the early stages of contamination. Germination, mycelial growth, probability of growth and probability of AFB1 production of an isolate of Aspergillus flavus were determined at 25 °C and two water activities (0.85 and 0.87) on 3% Pistachio Extract Agar (PEA). The percentage of germinated spores versus time was fitted to the modified Gompertz equation for the estimation of the germination parameters (geometrical germination time and germination rate). The radial growth curve for each colony was fitted to a linear model for the estimation of the apparent lag time for growth and the growth rate, and besides the time to visible growth was estimated. Binary data obtained from growth and AFB1 studies were modeled using logistic regression analysis. Both water activities led to a similar fungal growth and AFB1 production. In this study, given the suboptimal set conditions, it has been observed that germination is a stage far from the AFB1 production process. Once the probability of growth started to increase it took 6 days to produce AFB1, and when probability of growth was 100%, only a 40-57% probability of detection of AFB1 production was predicted. Moreover, colony sizes with a radius of 1-2 mm could be a helpful indicator of the possible AFB1 contamination in the commodity. Despite growth models may overestimate the presence of AFB1, their use would be a helpful tool for producers and manufacturers; from our data 5% probability of AFB1 production (initiation of production) would occur when a minimum of 60% probability of growth is observed. Legal restrictions are quite severe for these toxins, thus their control from the early stages of contamination throughout the food chain is of paramount

  9. Monitoring of aflatoxin G1, B1, G2, and B2 occurrence in some samples of walnut.

    PubMed

    Habibipour, Reza; Tamandegani, Parisa Rahimi; Farmany, Abbas

    2016-12-01

    This research was conducted to monitor the aflatoxigenic fungi and aflatoxin contamination of walnut in the Hamedan province. For this purpose, 40 samples were analyzed. Aspergillus, Alternaria, Rhizopus, Cladosporium, Fusarium, yeast, and some different bacteria were isolated from walnuts. Aspergillus is the most frequent genus. Aspergillus flavus was predominantly isolated. HPLC was used for evaluation of aflatoxin contamination of walnut samples. Aflatoxins G1 (AFG1), B1 (AFB1), G2 (AFG2), and B2 (AFB2) were produced by 20 isolates. AFG1 and AFB1 were being predominant at concentration ranges of 1.7-18.2 and 0-8.2 ngg(-1), respectively. Highest levels were found in one sample that was highly contaminated with Aspergillus flavus/Aspergillus parasiticus. Methyl beta cyclodextrin also was performed for detection of aflatoxigenic Aspergillus isolates. The results showed that only 31.6% (p < 0.05) of A. flavus and A. parasiticus isolates were able to produce aflatoxin. A significant difference was shown between shielded and unshielded walnut in aflatoxin contamination. The content of aflatoxin in most of the walnut samples did not reach to maximum tolerable limit for aflatoxin B1 in EU standard (p > 0.05). Thus, systematic and continues monitoring of walnuts is recommended.

  10. Aflatoxin levels and exposure assessment of Spanish infant cereals.

    PubMed

    Hernández-Martínez, Raquel; Navarro-Blasco, Iñigo

    2010-01-01

    Aflatoxins (AFB1, AFB2, AFG1 and AFG2) are immunosuppressant, mutagenic, teratogenic and carcinogenic agents with a widespread presence in foodstuffs. Since human exposure to aflatoxins occurs primarily by contaminated food intake, and given the greater susceptibility of infants to their adverse effects, the quantification of these mycotoxins in infant food based on cereals is of relevance. Aflatoxin levels were determined in 91 Spanish infant cereals classified in terms of non- and organically produced and several types from 10 different manufacturers, using a extraction procedure followed by inmunoaffinity column clean-up step and HPLC with fluorescence detection (FLD) and post-column derivatisation (Kobra Cell system). Daily aflatoxin intake was also assessed. Preliminary analysis showed a valuable incidence of detected infant cereal samples at an upper concentration level than the detection limit for total aflatoxin (66%), corresponding to a 46, 40, 34 and 11% for AFB1, AFB2, AFG1 and AFG2, respectively. Lower aflatoxin values (median, Q1, Q3) in conventional infant cereal (n = 74, AFB1: AFB2: n.d. (n.d.; 0.01), AFG1: AFB1: 0.02 (0.02; 0.21), AFB2: n.d. (n.d.; 0.03), AFG1: 0.02 (0.01; 0.05), and AFG2: 0.007 (n.d.; 0.02) and AFtotal: 0.05 (0.03; 0.31 µg kg(-1)) were found. In addition, five organic formulations (3.11, 1.98, 0.94, 0.47 and 0.21 µg kg(-1)) exceeded European AFB1 legislation (0.10 µg kg(-1)) versus two conventional cereals (0.35 and 0.12 µg kg(-1)). According to the type of infant cereal, those with cocoa had the highest aflatoxin levels. Gluten-free and cereals with dehydrated fruits had an intermediate level and milk- or honey-based cereals and multi-cereals contained the lowest levels. With the exception of the non-compliant cocoa-based organic formulation

  11. Interaction of mammary bovine ABCG2 with AFB1 and its metabolites and regulation by PCB 126 in a MDCKII in vitro model.

    PubMed

    Manzini, L; Halwachs, S; Girolami, F; Badino, P; Honscha, W; Nebbia, C

    2017-02-14

    The ATP-binding cassette efflux transporter ABCG2 plays a key role in the mammary excretion of drugs and toxins in humans and animals. Aflatoxins (AF) are worldwide contaminants of food and feed commodities, while PCB 126 is a dioxin-like PCB which may contaminate milk and dairy products. Both compounds are known human carcinogens. The interactions between AF and bovine ABCG2 (bABCG2) as well as the effects of PCB 126 on its efflux activity have been investigated by means of the Hoechst H33342 transport assay in MDCKII cells stably expressing mammary bABCG2. Both AFB1 and its main milk metabolite AFM1 showed interaction with bABCG2 even at concentrations approaching the legal limits in feed and food commodities. Moreover, PCB 126 significantly enhanced bABCG2 functional activity. Specific inhibitors of either AhR (CH233191) or ABCG2 (Ko143) were able to reverse the PCB 126-induced increase in bABCG2 transport activity, showing the specific upregulation of the efflux protein by the AhR pathway. The incubation of PCB 126-pretreated cells with AFM1 was able to substantially reverse such effect, with still unknown mechanism(s). Overall, results from this study point to AFB1 and AFM1 as likely bABCG2 substrates. The PCB 126-dependent increased activity of the transporter could enhance the ABCG2-mediated excretion into dairy milk of chemicals (i.e., drugs and toxins) potentially harmful to neonates and consumers.

  12. Multi-mycotoxin determination in cereals and derived products marketed in Tunisia using ultra-high performance liquid chromatography coupled to triple quadrupole mass spectrometry.

    PubMed

    Oueslati, Souheib; Romero-González, Roberto; Lasram, Salma; Frenich, Antonia Garrido; Vidal, José Luis Martínez

    2012-07-01

    The aim of the study was the use of a fast and simple method using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) for the simultaneous determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), fumonisins (FB1 and FB2), deoxynivalenol (DON), T2 and HT2 toxins in 58 samples of raw wheat (n = 34), barley (n = 5), sorghum (n = 3), processed wheat (n = 13) and breakfast cereals (n = 3) from Tunisian markets. The frequency of contamination of total samples with the analyzed mycotoxins was 50%. AFG2 was the most frequently detected in 11 samples (4 wheat, 4 barley and 3 sorghum) and it was detected at 5.2-52.4 μg/kg. HT2 toxin contaminated seven samples (4 wheat and 3 barley) and it was detected at 5.0-11.1 μg/kg. FB2 was detected in one wheat, sorghum, semolina and breakfast cereal samples at 5.0-61.5 μg/kg. FB1 was detected in three samples (2 sorghum and one barley) at 6.4-120 μg/kg. AFB1 was only found in two sorghum samples at 14 and 79.9 μg/kg. OTA was detected in one sorghum sample at concentrations below limit of quantification (5 μg/kg). The analytical results also showed that all the analyzed samples were not contaminated with DON, AFG1, AFB2 and T2 toxin.

  13. Inhibition of aflatoxin production and growth of Aspergillus parasiticus by Cuminum cyminum, Ziziphora clinopodioides, and Nigella sativa essential oils.

    PubMed

    Khosravi, Ali Reza; Shokri, Hojjatollah; Minooeianhaghighi, Mohammadhassan

    2011-12-01

    Aflatoxins are highly toxic and carcinogenic metabolites produced by Aspergillus parasiticus on food and agricultural commodities. Natural products may control the production of aflatoxins. The aims of this study were to evaluate the effects of the essential oils (EOs) of Cuminum cyminum, Ziziphora clinopodioides, and Nigella sativa on growth and aflatoxins production by A. parasiticus. Minimal inhibitory concentrations (MICs) and minimal fungicidal concentrations (MFCs) of the EOs were determined and compared with each other. Determination of aflatoxins (AFB(1), AFB(2), AFG(1), and AFG(2)) was performed by immunoaffinity column extraction using reverse phase-high performance liquid chromatography. The major oil components were α-pinene (30%) in C. cyminum, pulegone (37%) in Z. clinopodioides, and trans-anthol (38.9%) in N. sativa oils. In broth microdilution method, C. cyminum oil exhibited the strongest activity (MIC(90): 1.6; MFC: 3.5 mg/mL), followed by Z. clinopodioides (MIC(90): 2.1; MFC: 5.5 mg/mL) and N. sativa (MIC(90): 2.75; MFC: 6.25 mg/mL) oils against A. parasiticus (p<0.05). Aflatoxin production was inhibited at 0.25 mg/mL of C. cyminum and Z. clinopodioides oils, of which that of C. cyminum was a stronger inhibitor. C. cyminum EO caused significant reductions in values of 94.2% for AFB(1), 100% for AFB(2), 98.9% for AFG(1), 100% for AFG(2), and 97.5% for total aflatoxin. It is concluded that the EOs of C. cyminum, Z. clinopodioides, and N. sativa could be used as natural inhibitors in foods at low concentrations to protect from fungal and toxin contaminations by A. parasiticus.

  14. Determination for multiple mycotoxins in agricultural products using HPLC-MS/MS via a multiple antibody immunoaffinity column.

    PubMed

    Zhang, Zhaowei; Hu, Xiaofeng; Zhang, Qi; Li, Peiwu

    2016-05-15

    Mycotoxins usually found in agricultural products such as peanut, corn, and wheat, are a serious threat to human health and their detection requires multiplexed and sensitive analysis methods. Herein, a simultaneous determination for aflatoxin B1, B2, G1, G2, ochratoxin A, zearalanone and T-2 toxin was investigated using high performance liquid chromatography coupled with tandem mass spectrometry in a single run via a home-made multiple immunoaffinity column. Four monoclonal antibodies were produced in our lab against aflatoxins, ochratoxin A, zearalanone and T-2 toxin, respectively, then combined as a pool and bound to Sepharose-4B for affinity chromatography. Seven mycotoxins were effectively extracted from the agricultural product samples by using acetonitrile/water/acetic acid (80:19:1, v/v/v) Then, the extraction was cleanup by multiple immunoaffinity column. This method demonstrated a considerable linear range of 0.30-25, 0.12-20, 0.30-20, 0.12-20, 0.60-30, 0.30-25, and 1.2-40μgkg(-1)and lower limits of detection at 0.1, 0.04, 0.1, 0.04, 0.2, 0.1 and 0.4μgkg(-1) for AFB1, AFB2, AFG1, AFG2, OTA, ZEN and T-2, respectively, in comparison with previously reported methods, as well as excellent recoveries. The mIAC capacity for AFB1, AFB2, AFG1, AFG2, OTA, ZEN, and T-2 were 187, 181, 153, 151, 105, 130, 88ng, respectively. It was found that all of the 7 mycotoxins were present in 90 agricultural product samples. The proposed method meets the requirements for rapid sample preparation and highly sensitive identification of multiple mycotoxins in agricultural product and food safety. This method provides a promising alternative with high throughput and high sensitivity for rapid analysis of seven mycotoxins in the monitoring of food safety.

  15. Banana peel: an effective biosorbent for aflatoxins.

    PubMed

    Shar, Zahid Hussain; Fletcher, Mary T; Sumbal, Gul Amer; Sherazi, Syed Tufail Hussain; Giles, Cindy; Bhanger, Muhammad Iqbal; Nizamani, Shafi Muhammad

    2016-05-01

    This work reports the application of banana peel as a novel bioadsorbent for in vitro removal of five mycotoxins (aflatoxins (AFB1, AFB2, AFG1, AFG2) and ochratoxin A). The effect of operational parameters including initial pH, adsorbent dose, contact time and temperature were studied in batch adsorption experiments. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHpzc) analysis were used to characterise the adsorbent material. Aflatoxins' adsorption equilibrium was achieved in 15 min, with highest adsorption at alkaline pH (6-8), while ochratoxin has not shown any significant adsorption due to surface charge repulsion. The experimental equilibrium data were tested by Langmuir, Freundlich and Hill isotherms. The Langmuir isotherm was found to be the best fitted model for aflatoxins, and the maximum monolayer coverage (Q0) was determined to be 8.4, 9.5, 0.4 and 1.1 ng mg(-1) for AFB1, AFB2, AFG1 and AFG2 respectively. Thermodynamic parameters including changes in free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) were determined for the four aflatoxins. Free energy change and enthalpy change demonstrated that the adsorption process was exothermic and spontaneous. Adsorption and desorption study at different pH further demonstrated that the sorption of toxins was strong enough to sustain pH changes that would be experienced in the gastrointestinal tract. This study suggests that biosorption of aflatoxins by dried banana peel may be an effective low-cost decontamination method for incorporation in animal feed diets.

  16. The surface-enhanced Raman spectra of aflatoxins: spectral analysis, density functional theory calculation, detection and differentiation.

    PubMed

    Wu, Xiaomeng; Gao, Simin; Wang, Jia-Sheng; Wang, Hongyan; Huang, Yao-Wen; Zhao, Yiping

    2012-09-21

    High-quality surface-enhanced Raman scattering (SERS) spectra of aflatoxin (AF) B(1), B(2), G(1) and G(2) have been acquired using silver nanorod (AgNR) array substrates fabricated by oblique angle deposition method. Significant vibrational peaks are identified on the argon plasma-cleaned substrates, and those peaks agree very well with the Raman spectra calculated by density function theory (DFT). The concentration-dependent SERS detection is also explored. The relationship between the concentration (C) of different AFs and the SERS intensity (I) of the Raman peak at Δν = 1592 cm(-1) is found to follow the general relationship I = AC(α), with α ranging from 0.32 to 0.46 for the four AFs. The limits of detection (LODs) reach 5 × 10(-5) mol L(-1) for AFB(1), 1 × 10(-4) mol L(-1) for AFB(2), and 5 × 10(-6) mol L(-1) for both AFG(1) and AFG(2) in bulk solution, or 6.17 × 10(-16) mol/1.93 × 10(-4) ng of AFB(1), 1.23 × 10(-15) mol/3.88 × 10(-4) ng for AFB(2), 6.17 × 10(-17) mol/2.03 × 10(-5) ng for AFG(1), and 6.17 × 10(-17) mol/2.04 × 10(-5) ng for AFG(2) per laser spot. Principal component analysis (PCA) is used to successfully differentiate these four different kinds of AFs at different concentrations up to their detection limits. The LODs obtained from PCA agree with the LODs obtained by using peak fitting method. With such a low detection limit and outstanding differentiation ability, we prove the possibility of utilizing the SERS detection system as a platform for highly sensitive mycotoxin detection.

  17. Aflatoxin levels in chronic hepatitis B patients with cirrhosis or hepatocellular carcinoma in Balıkesir, Turkey.

    PubMed

    Aydın, M; Aydın, S; Bacanlı, M; Başaran, N

    2015-11-01

    Aflatoxins, the secondary metabolites produced by species of naturally occurring Aspergilli, are commonly found in food such as cereals, dried fruits and juice, wine, beer and spices. They are hepatotoxic and are well known human carcinogens based on evidence from human studies. Aflatoxins are an environmental risk factor for the development of hepatocellular carcinoma (HCC). Chronic hepatitis B-infected patients are at increased risk of cirrhosis, hepatic failure and liver cancer. This study was designed to determine the serum aflatoxin B1 (AFB1 ), aflatoxin B2 (AFB2 ), aflatoxin G1 (AFG1 ) and aflatoxin G2 (AFG2 ) concentrations using high-pressure liquid chromatography (HPLC) in hepatitis B-infected patients with or without cirrhosis and liver cancer, alongside healthy controls in Balıkesir, Turkey. The mean AFB1 and total AF levels in patients without liver cancer and cirrhosis were significantly higher than healthy controls. The mean AFB1 and total AF levels in patients with chronic hepatitis B and HCC were significantly higher than infected patients with or without cirrhosis. These results suggest that patients with chronic hepatitis B who are exposed to AFs are at increased risk for developing HCC, which might be prevented by reducing consumption of contaminated foods.

  18. Aflatoxins, ochratoxins and zearalenone in sorghum and sorghum products in Sudan.

    PubMed

    Elbashir, Abdalla A; Ali, Salah Eldeen A

    2014-01-01

    This survey examined 60 samples of sorghum and 30 samples of sorghum products from three states (Khartoum, Kordofan and Gadarif) of Sudan for aflatoxin B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2), ochratoxin A and B (OTA, OTB) and zearalenone (ZEN), using high performance liquid chromatography with fluorescence detection. The limits of detection and limits of quantification were in the range 0.01-0.6 µg kg(-1) and 0.03-2.0 µg kg(-1), respectively. The frequency of contaminated samples with AFB1 from Khartoum, Gadarif and Kordofan state was 38.1%, 22.2% and 23.8%, respectively. Only two samples of sorghum from Khartoum state were contaminated with OTA (3.3%). Concentrations of OTA and OTB were low and may not cause problems. No sample of sorghum or sorghum products was contaminated with ZEN. Some sorghum samples contained AFB1 concentrations above the European Union regulatory limits. The highest contaminated samples were found in Khartoum state.

  19. Determination of 16 mycotoxins in vegetable oils using a QuEChERS method combined with high-performance liquid chromatography-tandem mass spectrometry.

    PubMed

    Zhao, Hongxia; Chen, Xiuying; Shen, Chen; Qu, Baocheng

    2017-02-01

    A simple and efficient method for determining multiple mycotoxins was developed using a QuEChERS (quick, easy, cheap, effective, rugged and safe)-based extraction procedure in vegetable oils. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used for the quantification and confirmation of 16 chemically diversified mycotoxins. Different extraction procedures were studied and optimised by spiking 16 analytes into blank matrix, and the extraction with 85% MeCN solution and C18 as cleaning sorbent allowed an efficient recovery of 72.8-105.8% with RSDs less than 7%. The limit of detection (LOD) ranged from 0.04 to 2.9 ng g(-1). The developed method was finally applied to screen mycotoxins in 62 vegetable oil samples. Zearalenone (ZEN), aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and α-zearalenol (α-ZOL) were detected, with maximum concentrations of 0.59 (AFG1)-42.5 (ZEN) ng g(-1). The method developed has the advantages of high sensitivity, accuracy and selectivity, and it can be applied to the target screening of mycotoxins in real samples.

  20. Reduction of Aflatoxins in Apricot Kernels by Electronic and Manual Color Sorting

    PubMed Central

    Zivoli, Rosanna; Gambacorta, Lucia; Piemontese, Luca; Solfrizzo, Michele

    2016-01-01

    The efficacy of color sorting on reducing aflatoxin levels in shelled apricot kernels was assessed. Naturally-contaminated kernels were submitted to an electronic optical sorter or blanched, peeled, and manually sorted to visually identify and sort discolored kernels (dark and spotted) from healthy ones. The samples obtained from the two sorting approaches were ground, homogenized, and analysed by HPLC-FLD for their aflatoxin content. A mass balance approach was used to measure the distribution of aflatoxins in the collected fractions. Aflatoxin B1 and B2 were identified and quantitated in all collected fractions at levels ranging from 1.7 to 22,451.5 µg/kg of AFB1 + AFB2, whereas AFG1 and AFG2 were not detected. Excellent results were obtained by manual sorting of peeled kernels since the removal of discolored kernels (2.6%–19.9% of total peeled kernels) removed 97.3%–99.5% of total aflatoxins. The combination of peeling and visual/manual separation of discolored kernels is a feasible strategy to remove 97%–99% of aflatoxins accumulated in naturally-contaminated samples. Electronic optical sorter gave highly variable results since the amount of AFB1 + AFB2 measured in rejected fractions (15%–18% of total kernels) ranged from 13% to 59% of total aflatoxins. An improved immunoaffinity-based HPLC-FLD method having low limits of detection for the four aflatoxins (0.01–0.05 µg/kg) was developed and used to monitor the occurrence of aflatoxins in 47 commercial products containing apricot kernels and/or almonds commercialized in Italy. Low aflatoxin levels were found in 38% of the tested samples and ranged from 0.06 to 1.50 μg/kg for AFB1 and from 0.06 to 1.79 μg/kg for total aflatoxins. PMID:26797635

  1. Multi-class mycotoxins analysis in Angelica sinensis by ultra fast liquid chromatography coupled with tandem mass spectrometry.

    PubMed

    Liu, Qiutao; Kong, Weijun; Guo, Weiying; Yang, Meihua

    2015-04-15

    An ultra fast liquid chromatography coupled with tandem mass spectrometry (UFLC-MS/MS) method was developed and validated for simultaneous analysis of multi-class mycotoxins including aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), fumonisins (FB1 and FB2) and zearalanone (ZEN) in 20 batches of Angelica sinensis samples collected from different markets and stores in China. The eight mycotoxins were extracted and cleaned up by using QuEChERS-based procedure, and then were quantified under the multiple reaction monitoring (MRM) together with positive and negative ionization modes. Focusing on the optimization of extraction and clean-up conditions, as well as UFLC separation and MS/MS parameters of targeted analytes, the developed method expressed good linearity for the eight mycotoxins within their respective linear ranges with correlation coefficients all higher than 0.9974. The limits of detection (LODs) and quantification (LOQs) ranged from 0.005 to 0.125 μg/kg and from 0.0625 to 0.25 μg/kg, respectively. Recoveries for spiked A. sinensis sample at three different levels were all above 78.9% with relative standard deviations (RSDs) below 6.36% for all analytes. Analysis of real samples demonstrated that two visibly moldy A. sinensis samples were detected with AFB1 of 2.07 and 2.92 μg/kg, and AFG1 of 2.84 and 1.53 μg/kg. The proposed quantitative method with significant advantages including simple pretreatment, rapid determination and high sensitivity would be the preferred candidate for the determination and quantification of multi-class mycotoxin contaminants in complex matrixes, which well fulfilled the maximum residue limits (MRLs) from various countries.

  2. Simultaneous multi-mycotoxin determination in nutmeg by ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection.

    PubMed

    Kong, Wei-Jun; Liu, Shu-Yu; Qiu, Feng; Xiao, Xiao-He; Yang, Mei-Hua

    2013-05-07

    A simple and sensitive analytical method based on ultrasound-assisted solid-liquid extraction and immunoaffinity column clean-up coupled with high performance liquid chromatography and on-line post-column photochemical derivatization-fluorescence detection (USLE-IAC-HPLC-PCD-FLD) has been developed for simultaneous multi-mycotoxin determination of aflatoxins B1, B2, G1, G2 (AFB1, AFB2, AFG1, AFG2) and ochratoxin A (OTA) in 13 edible and medicinal nutmeg samples marketed in China. AFs and OTA were extracted from nutmeg samples by ultrasonication using a methanol : water (80 : 20, v/v) solution, followed by an IAC clean-up step. Different USL extraction conditions, pre-processing ways for nutmeg sample and clean-up columns for mycotoxins, as well as HPLC-PCD-FLD parameters (mobile phase, column temperature, elution procedure, excitation and emission wavelengths) were optimized. This method, which was appraised for analyzing nutmeg samples, showed satisfactory results with reference to limits of detection (LODs) (from 0.02 to 0.25 μg kg(-1)), limits of quantification (LOQs) (from 0.06 to 0.8 μg kg(-1)), linear ranges (up to 30 ng mL(-1) for AFB1, AFG1 and OTA and 9 ng mL(-1) for AFB2 and AFG2), intra- and inter-day variability (all <2%) and average recoveries (from 79.6 to 90.8% for AFs and from 93.6 to 97.3% for OTA, respectively). The results of the application of developed method in nutmeg samples have elucidated that four samples were detected with contamination of AFs and one with OTA. AFB1 was the most frequently found mycotoxin in 30.8% of nutmeg samples at contamination levels of 0.73-16.31 μg kg(-1). At least two different mycotoxins were co-occurred in three samples, and three AFs were simultaneously detected in one sample.

  3. Survey of aflatoxins in Kashkineh: A traditional Iranian food

    PubMed Central

    Mardani, M; Rezapour, S; Rezapour, P

    2011-01-01

    Background and Objectives Aflatoxins are mycotoxins produced by Aspergillus flavus and Aspergillus parasiticus that can contaminate human and animal foods, including corn, wheat, rice, peanuts, and many other crops resulting in the illness or death of human and animal consumers. The aim of this study was to detect aflatoxin B1, B2, G1, G2 and total aflatoxin in Kashkineh, a traditional Iranian food. Materials and Methods This survey was conducted to detect aflatoxins on 41 samples of Kashkineh. The samples were randomly collected from traditional bazaars and supermarkets of Khorramabad city of Iran. The presence and quantity of aflatoxins was determined by high performance liquid chromatography (HPLC). Results The average concentrations of AFB1, AFB2, AFG1, and AFG2 in all samples and in a mixed sample of all samples were not detectable (ND). The only sample that showed aflatoxin contamination was sample number 29 of which the AFB1 concentration was 0.64 ng/g. Conclusion Although some people believe Kashkineh is carcinogenic due to toxins, this study showed kashkineh is not contaminated with aflatoxins. PMID:22347598

  4. Aflatoxin in pistachio nuts used as ingredients in Gaz sweets produced in Isfahan, Iran.

    PubMed

    Jahanmard, Elham; Azarani, Farzaneh; Sharifi, Mehran; Esfandiari, Zahra

    2014-01-01

    In Isfahan province of Iran, pistachio and almond are used specifically as ingredients to produce Gaz sweets, which are a typical product of Isfahan and exported to many countries. In this survey, 112 samples were gathered from different corresponding Gaz producers from 2007 to 2012 to evaluate the occurrence of aflatoxins (AF) in these products. Samples were analysed for AFB1, AFB2, AFG1 and AFG2 using immunoaffinity column clean-up (IC) and quantified by high-performance liquid chromatography (HPLC) with fluorescence detection. Among the samples analysed, AFB1 was detected in 13.4% of the samples above the maximum limit (ML) as set in Iran (5 µg/kg). Total AF (AFT) was above the ML in 9.8% of the samples. This study showed that full consideration is equally essential for nuts used as ingredients in special food products such as the Gaz sweets as for nuts for direct human consumption. It suggests a need for modifying the current trend of supervision.

  5. Mycological and aflatoxin contamination of peanuts sold at markets in Kinshasa, Democratic Republic of Congo, and Pretoria, South Africa.

    PubMed

    Kamika, Ilunga; Mngqawa, Pamella; Rheeder, John P; Teffo, Snow L; Katerere, David R

    2014-01-01

    Peanut (Arachis hypogaea L.) is an important food crop in sub-Saharan Africa. In this survey, the mycological and aflatoxin contamination of peanuts collected from Kinshasa, Democratic Republic of Congo, and Pretoria, South Africa, was assessed. Twenty peanut samples were purchased randomly at informal markets in the two cities and analysed for mycoflora and aflatoxins (AFB1, AFB2, AFG1 and AFG2) using standard methods. The results indicated that 95% of the Kinshasa samples and 100% of the Pretoria samples were contaminated with aflatoxigenic fungi in the ranges 20-49,000 and 40-21,000 CFU/g, respectively. Seventy-five per cent of the Kinshasa samples and 35% of the Pretoria samples exceeded the maximum limits of AFB1 as set by The Joint FAO/WHO Expert Committee on Food Additives. Residents of both cities are at a high risk of aflatoxin exposure despite their apparent cultural, socio-economic, geographic and climatic differences. Further work needs to be done to understand the supply chains of peanut trade in informal markets of the two countries so that interventions are well targeted on a regional rather than a national level.

  6. Conversion of 11-hydroxy-O-methylsterigmatocystin to aflatoxin G1 in Aspergillus parasiticus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In aflatoxin biosynthesis, aflatoxins G1 (AFG1) and B1 (AFB1) are independently produced from a common precursor, O-methylsterigmatocystin (OMST). Recently, 11-hydroxy-O-methylsterigmatocystin (HOMST) was identified as a later precursor involved in the conversion of OMST to AFB1. However, the invo...

  7. Oxidative degradation and detoxification of mycotoxins using a novel source of ozone.

    PubMed

    McKenzie, K S; Sarr, A B; Mayura, K; Bailey, R H; Miller, D R; Rogers, T D; Norred, W P; Voss, K A; Plattner, R D; Kubena, L F; Phillips, T D

    1997-08-01

    Practical methods to degrade mycotoxins using ozone gas (O3) have been limited due to low O3 production capabilities of conventional systems and their associated costs. Recent advances in electrochemistry (i.e. proton-exchange membrane and electrolysis technologies) have made available a novel and continuous source of O3 gas up to 20% by weight. It is possible that the rapid delivery of high concentrations of O3 will result in mycotoxin degradation in contaminated grains--with minimal destruction of nutrients. The major objectives of this study were to investigate the degradation and detoxification of common mycotoxins in the presence of high concentrations of O3. In this study, aqueous equimolar (32 microM) solutions of aflatoxins B1 (AfB1), B2 (AfB2), G1 (AfG1), G2 (AfG2), cyclopiazonic acid (CPA), fumonisin B1 (FB1), ochratoxin A (OA), patulin, secalonic acid D (SAD) and zearalenone (ZEN) were treated with 2, 10 and/or 20 weight% O3 over a period of 5.0 min and analysed by HPLC. Results indicated that AfB1 and AfG1 were rapidly degraded using 2% O3, while AfB2 and AfG2 were more resistant to oxidation and required higher levels of O3 (20%) for rapid degradation. In other studies, patulin, CPA, OA, SAD and ZEN were degraded at 15 sec, with no by-products detectable by HPLC. Additionally, the toxicity of these compounds (measured by a mycotoxin-sensitive bioassay) was significantly decreased following treatment with O3 for 15 sec. In another study, FB1 (following reaction with O3) was rapidly degraded at 15 sec, with the formation of new products. One of these appeared to be a 3-keto derivative of FB1. Importantly, degradation of FB1 did not correlate with detoxification, since FB1 solutions treated with O3 were still positive in two bioassay systems.

  8. Comparative specificities of Calreticulin Transacetylase to O-acetyl, N-acetyl and S-acetyl derivative of 4-methylcoumarins and their inhibitory effect on AFB1-induced genotoxicity in vitro and in vivo.

    PubMed

    Kumar, Ajit; Ponnan, Prija; Raj, Hanumantharao G; Parmar, Virinder S; Saso, Luciano

    2013-02-01

    We have earlier conclusively established the Calreticulin Transacetylase (CRTAase) catalyzed modifications of functional proteins such as cytochrome-P450-linked mixed function oxidases (Cyt-P450-linked MFOs), NADPH cytochrome c reductase, and glutathione S-transferase by acetoxy derivatives of polyphenols. In this study, we have investigated the comparative specificities of CRTAase to N-acetyl derivative, 7-acetamido-4-methylcoumarin (7-N-AMC), O-acetyl derivative, 7-acetoxy-4-methylcoumarin (7-AMC), S-acetyl derivative, 7-thioacetyl-4-methycoumarin (7-S-AMC) and their parent compounds in the modulation of catalytic activities of aforesaid proteins. Special attention concentrated on the comparative inhibitory effect of aforesaid acetyl moiety on Cyt-P450-linked MFOs such as 7-ethoxyresorufin O-deethylase (EROD), pentoxyresorufin O-dealkylase (PROD) and aflatoxin B(1) (AFB(1))-induced genotoxicity in vitro and in vivo. The results clearly indicated that N-acetyl and O-acetyl derivatives were better substrates for CRTAase while the S-acetyl was found to be a poorer substrate. Our study involving atomic charge, charge density and molecular electrostatic potential (MEP) calculations indicated the pivotal role of electronegativity and charge distribution values of O, N and S atoms of the acetyl group at C-7 position of the 4-methylcoumarins in CRTAase activity. These facts reinforce our hypothesis that the CRTAase catalyzed modifications of the catalytic activities of aforesaid proteins by acetyl derivative of 4-methylcoumarins is probably due to acetylation of these proteins.

  9. Brazil nuts are subject to infection with B and G aflatoxin-producing fungus, Aspergillus pseudonomius.

    PubMed

    Massi, Fernanda Pelisson; Vieira, Maria Lúcia Carneiro; Sartori, Daniele; Penha, Rafael Elias Silva; de Freitas Munhoz, Carla; Ferreira, Josué Maldonado; Iamanaka, Beatriz Thie; Taniwaki, Marta Hiromi; Frisvad, Jens C; Fungaro, Maria Helena Pelegrinelli

    2014-09-01

    The exploitation of the Brazil nut is one of the most important activities of the extractive communities of the Amazon rainforest. However, its commercialization can be affected by the presence of aflatoxins produced by fungi, namely Aspergillus section Flavi. In the present study, we investigated a collection of Aspergillus nomius strains isolated from Brazil nuts using different approaches, including morphological characters, RAPD and AFLP profiles, partial β-tubulin and calmodulin nucleotide sequences, aflatoxin patterns, as well as tolerance to low water activity in cultured media. Results showed that most of the isolates do belong to A. nomius species, but a few were re-identified as Aspergillus pseudonomius, a very recently described species. The results of the analyses of molecular variance, as well as the high pairwise FST values between A. nomius and A. pseudonomius suggested the isolation between these two species and the inexistence of gene flow. Fixed interspecific nucleotide polymorphisms at β-tubulin and calmodulin loci are presented. All A. pseudonomius strains analyzed produced aflatoxins AFB1, AFB2, AFG1 and AFG2. This study contains the first-ever report on the occurrence in Brazil nuts of A. pseudonomius. The G-type aflatoxins and the mycotoxin tenuazonic acid are reported here for the first time in A. pseudonomius.

  10. Aflatoxins of type B and G affect porcine dendritic cell maturation in vitro.

    PubMed

    Mehrzad, Jalil; Devriendt, Bert; Baert, Kim; Cox, Eric

    2015-01-01

    The toxic effects of highly carcinogenic mycotoxins, especially aflatoxins (AF), on key antigen-presenting cells, such as dendritic cells (DC), are largely unknown. To elucidate the effect of AF on DC function, porcine monocyte-derived DC (MoDC) were treated with a mixture of several AF (i.e., AFB1, AFB2, AFG1, and AFG2) and the phagocytic capacity, the membrane expression level of several DC activation markers, the T-cell proliferation-inducing capacity, and the cytokine secretion pattern were assessed. As compared to untreated MoDC, AF significantly up-regulated the expression of the co-stimulatory molecules CD25 and CD80/86. However, the phagocytic activity of MoDC was not affected by AF treatment. While the cytokine secretion pattern of AF-treated MoDC was similar to control MoDC, the T-cell proliferation-inducing capacity of MoDC was increased upon aflatoxin treatment. The results indicate that a mixture of naturally occurring AF enhances the antigen-presenting capacity of DC, which could explain the observed immunotoxicity of AF by breaking down tolerance and further emphasizes the need to reduce the admissible level of AF in agricultural commodities.

  11. Estimated exposure to EU regulated mycotoxins and risk characterization of aflatoxin-induced hepatic toxicity through the consumption of the toasted cereal flour called "gofio", a traditional food of the Canary Islands (Spain).

    PubMed

    Luzardo, Octavio P; Bernal-Suárez, María Del Mar; Camacho, María; Henríquez-Hernández, Luis Alberto; Boada, Luis D; Rial-Berriel, Cristian; Almeida-González, Maira; Zumbado, Manuel; Díaz-Díaz, Ricardo

    2016-07-01

    "Gofio" is a type of flour made from toasted grain, which is part of the staple food in the Canary Islands, Spain, in which the occurrence of Aflatoxins B1, B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2), Fumonisins B1 and B2 (FB1 and FB2) Ochratoxin A (OTA), Deoxynivalenol (DNV) and Zearalenone (ZEA) was evaluated. 83% of the samples were contaminated with at least one mycotoxin and 69.2% of the analyzed samples showed co-occurrence of mycotoxins (range 2 to 8). All the concentrations were well below the established limits (maximum values of AFs=0.42 μg/kg; FBs=178.3 μg/kg; OTA=0.3 μg/kg; DON=92.5 μg/kg; and ZEA=9.9 μg/kg). The daily dietary exposure to total AFs was estimated to be 7.1% of the TDI. This value was almost double in children, and considering the upper-bound approach could reach 35% of the TDI. For the rest of mycotoxins, the consumers would be exposed to less than 2% of their TDIs. The risk characterization indicates that there is a potential risk in developing aflatoxin induced liver cancer due to gofio consumption in the subpopulation which is simultaneously exposed to other hepatocarcinogens, such as the hepatitis B virus.

  12. Determination of Mycotoxins in Brown Rice Using QuEChERS Sample Preparation and UHPLC-MS-MS.

    PubMed

    Jettanajit, Adisorn; Nhujak, Thumnoon

    2016-01-01

    QuEChERS sample preparation was optimized and validated using solvent extraction with 10% (v/v) acetic acid-containing acetonitrile in the presence of four salts (anh. MgSO4, NaCl, sodium citrate tribasic dihydrate and sodium citrate dibasic sesquihydrate) and dispersive solid-phase extraction with mixed sorbents (octadecylsilane, primary and secondary amine and silica sorbents) for an ultra high performance liquid chromatography-tandem mass spectrometric determination of nine mycotoxins in brown rice: aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisins (FB1 and FB2), deoxynivalenol, ochratoxin A and zearalenone (ZON). Our developed method allows for the determination of trace levels of mycotoxins with method detection limits in the range of 1.4-25 µg/kg, below the maximum limits of EU regulations, and with an acceptable accuracy and precision, and recoveries in the range of 81-101% with relative standard deviations of 5-19% over a mycotoxin concentration range of 5.0-1,000 µg/kg. Six out of fourteen real samples of brown rice were found to be contaminated with at least one of these mycotoxins, ranging from 2.49-5.41 µg/kg of FB1, 4.33 ± 0.04 µg/kg of FB2 and 6.10-14.88 µg/kg of ZON.

  13. The potential effects of Zataria multiflora Boiss essential oil on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes of toxigenic Aspergillus parasiticus.

    PubMed

    Yahyaraeyat, R; Khosravi, A R; Shahbazzadeh, D; Khalaj, V

    2013-01-01

    This study aims at evaluating the effects of Zataria multiflora (Z. multiflora) essential oil (EO) on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes. Total RNAs of Aspergillus parasiticus (A.parasiticus) ATCC56775 grown in yeast extract sucrose (YES) broth medium treated with Z. multiflora EO were subjected to reverse transcription- polymerase chain reaction (RT-PCR). Specific primers of nor-1, ver-1, omt-A and aflR genes were used. In parallel mycelial dry weight of samples were measured and all the media were assayed by high-pressure liquid chromatography (HPLC) for aflatoxinB1 (AFB1), aflatoxinB2 (AFB2), aflatoxinG1 (AFG1), aflatoxinG2 (AFG2) and aflatoxin total (AFTotal) production. The results showed that mycelial dry weight and aflatoxin production reduce in the presence of Z. multiflora EO (100 ppm) on day 5 of growth. It was found that the expression of nor-1, ver-1, omt-A and aflR genes was correlated with the ability of fungus to produce aflatoxins on day 5 in YES medium. RT-PCR showed that in the presence of Z.multiflora EO (100 ppm) nor-1, ver-1 and omtA genes expression was reduced. It seems that toxin production inhibitory effects of Z. multiflora EO on day 5 may be at the transcription level and this herb may cause reduction in aflatoxin biosynthesis pathway genes activity.

  14. Survey of 11 mycotoxins in wheat flour in Hebei province, China.

    PubMed

    Liu, Yinping; Lu, Yang; Wang, Liying; Chang, Fengqi; Yang, Lixin

    2015-01-01

    A survey of 11 mycotoxins in 348 wheat flour samples marketed in Hebei province of China were analysed by liquid chromatography-tandem mass spectrometry, was carried out. The selected mycotoxins consisted of four aflatoxins (AFs: AFB1, AFB2, AFG1 and AFG2) and seven Fusarium toxins, i.e. deoxynivalenol (DON), nivalenol, 3-acetyldeoxynivalenol and 15-acetyldeoxynivalenol, zearalenone, Fusarenon-X and deoxynivalenol-3-glucoside. Results indicated that most of the wheat samples analysed were contaminated with mycotoxins. Wheat was most susceptible to DON (91.4% contamination), with a mean level of 240 μg kg(-1). On average the probable daily intake (PDI, expressed as µg kg(-1) body weight day(-1)) of mycotoxins was within the provisional maximum tolerable daily intake (PMTDI, 2.0 µg kg(-1) of body weight day(-1)) as set by the Joint FAO/WHO Expert Committee on Food Additives. Nevertheless, exposure assessment revealed that the maximum PDI of mycotoxins was 4.06 µg kg(-1) body weight day(-1), which was twice the PMTDI value. Thus, consistent monitoring is recommended, as to keep the contamination level under control.

  15. The first report of A. novoparasiticus, A. arachidicola and A. pseudocaelatus in Brazilian corn kernels.

    PubMed

    Viaro, Helena Paula; da Silva, Josué José; de Souza Ferranti, Larissa; Bordini, Jaqueline Gozzi; Massi, Fernanda Pelisson; Fungaro, Maria Helena Pelegrinelli

    2017-02-21

    Maize is one of the most important commercial crops cultivated throughout the world, mostly in tropical and subtropical countries. It is highly susceptible to mycotoxins, toxic secondary metabolites produced by fungi. In this study, we assessed freshly harvested corn produced in Brazil for aflatoxin contamination and the presence of Aspergillus. B type aflatoxins (AFB1+AFB2) were detected in 56% of 16 grain samples, while G type aflatoxins (AFG1+AFG2) were detected in 25%. Of the total number of grains (n=1920) evaluated for the presence of fungi species, 4.7% were infected with Aspergillus species, 74.5% and 16.7% respectively with Fusarium and Penicillium species and 4.1% with other fungi genera. In total, 89 Aspergillus isolates were identified, most (86 isolates) characterized as belonging to Aspergillus section Flavi, and the remainder to Aspergillus section Cremei (2 isolates) and Aspergillus section Terrei (1 isolate). All the isolates of section Flavi were subjected to molecular analysis. They were found to belong to six species, including Aspergillus novoparasiticus, Aspergillus arachidicola and Aspergillus pseudocaelatus, all aflatoxins B and G producing species, which are herein described for the first time infecting corn kernels.

  16. Fusarium and Aspergillus mycotoxins contaminating wheat silage for dairy cattle feeding in Uruguay.

    PubMed

    Del Palacio, Agustina; Bettucci, Lina; Pan, Dinorah

    Wheat is one of the most important cultivated cereals in Uruguay for human consumption; however, when harvest yields are low, wheat is usually used in ensiling for animal feeding. Ensiling is a forage preservation method that allows for storage during extended periods of time while maintaining nutritional values comparable to fresh pastures. Silage is vulnerable to contamination by spoilage molds and mycotoxins because ensilage materials are excellent substrates for fungal growth. The aim of the study was to identify the mycobiota composition and occurrence of aflatoxins and DON from wheat silage. A total of 220 samples of wheat were collected from four farms in the southwest region of Uruguay were silage practices are developed. The main fungi isolated were Fusarium (43%) and Aspergillus (36%), with Fusarium graminearum sensu lato and Aspergillus section Flavi being the most prevalent species. Aflatoxin concentrations in silo bags ranged from 6.1 to 23.3μg/kg, whereas DON levels ranged between 3000μg/kg and 12,400μg/kg. When evaluating aflatoxigenic capacity, 27.5% of Aspergillus section Flavi strains produced AFB1, 5% AFB2, 10% AFG1 and 17.5% AFG2. All isolates of F. graminearum sensu lato produced DON and 15-AcDON. The results from this study contribute to the knowledge of mycobiota and mycotoxins present in wheat silage.

  17. High-throughput determination of multi-mycotoxins in Chinese yam and related products by ultra fast liquid chromatography coupled with tandem mass spectrometry after one-step extraction.

    PubMed

    Li, Menghua; Kong, Weijun; Li, Yanjun; Liu, Hongmei; Liu, Qiutao; Dou, Xiaowen; Ou-Yang, Zhen; Yang, Meihua

    2016-06-01

    A simple, accurate and sensitive ultra fast liquid chromatography coupled with tandem mass spectrometry (UFLC-MS/MS) method was developed for high-throughput determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), fumonisins (FB1 and FB2) and zearalenone (ZEA) in Chinese yam, yam flours and yam-derived products. Mycotoxins were extracted from the samples with methanol-water-formic acid (79:20:1, v/v/v) and no further cleanup step before analysis. After optimization of some crucial parameters including sample preparation, chromatographic separation and MS/MS conditions, the method was successfully validated to exhibit excellent performance in terms of satisfactory linearity (r≥0.9977), limits of detection (≤0.15ngmL(-1)) and quantification (≤0.5ngmL(-1)) with good precision (RSD for intra- and inter-day variations of ≤4.65% and 6.31%, respectively), good accuracy (recoveries of 71.0-106.0%) and robustness, together with short run time (8min/sample). The developed method was applied for simultaneous detection and quantification of the above 8 mycotaxins in 27 batches of Chinese yam and related products collected from different markets and pharmacies in China. The results revealed that 1 normal sample and 4 moldy samples were found to be contaminated with different mycotoxins. The detected concentrations of AFB1 in 2 moldy samples exceeded the regulatory maximum residue levels. The proposed method was capable for simultaneous determination of mycotoxins in this and other types of complex matrices.

  18. Potential for aflatoxin B1 and B2 production by Aspergillus flavus strains isolated from rice samples

    PubMed Central

    Lai, Xianwen; Zhang, He; Liu, Ruicen; Liu, Chenglan

    2014-01-01

    In this study, we investigated the potential for aflatoxin B1 (AFB1) and B2 (AFB2) production in rice grain by 127 strains of Aspergillus flavus isolated from rice grains collected from China. These strains were inoculated onto rice grains and incubated at 28 °C for 21 days. AFB1 and AFB2 were extracted and quantified by high-performance liquid chromatography coupled with fluorescence detection. Among the tested strains, 37% produced AFB1 and AFB2 with levels ranging from 175 to 124 101 μg kg−1 for AFB1 and from not detected to 10 329 μg kg−1 for AFB2. The mean yields of these isolates were 5884 μg kg−1 for AFB1 and 1968 μg kg−1 for AFB2. Overall, most of the aflatoxigenic strains produced higher levels of AFB1 than AFB2 in rice. The obtained information is useful for assessing the risk of aflatoxin contamination in rice samples. PMID:25737649

  19. Effect of dietary acids on the formation of aflatoxin B2a as a means to detoxify aflatoxin B1.

    PubMed

    Rushing, Blake R; Selim, Mustafa I

    2016-09-01

    Aflatoxin B1 (AFB1) is a class 1 carcinogen and a common food contaminant worldwide with widely uncontrolled human exposure. The ability of organic acids to transform AFB1 into a known detoxified form, aflatoxin B2a (AFB2a), was investigated using high performance liquid chromatography-electrospray ionisation-time of flight mass spectrometry (HPLC/ESI/TOF/MS). The identity of the transformation product was confirmed by accurate mass measurement, chromatographic separation from other aflatoxins, H(1)-nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy. Of the weak acids tested, citric acid was found to be the most effective for AFB2a formation. At room temperature, 1 M citric acid was able to convert > 97% of AFB1 to AFB2a over 96 h of treatment. Up to 98% transformation was achieved by boiling AFB1 in the presence of citric acid for 20 min. AFB1 hydration after ingestion was explored by spiking AFB1 into simulated gastric fluid containing citric acid. Under these conditions, > 71% of AFB1 was hydrated to AFB2a and did not show any reversion to the parent compound after being transferred to a neutral solution. These results provide a basis for a practical and effective method for detoxification of AFB1 in contaminated foods.

  20. The use of regenerated immunoaffinity columns for aflatoxins B1, B2, G1 and G2 in peanut confection.

    PubMed

    Iha, Maria Helena; Mini, Camila Alessandra; Okada, Isaura Akemi; Briganti, Rita de Cássia; Trucksess, Mary W

    2017-02-03

    The aim of this study was to investigate the feasibility of using multitime-regenerated immunoaffinity column (IAC) for aflatoxins B1, B2, G1 and G2 in peanut confection. After each use, the IAC was washed immediately with phosphate-buffered saline and stored for >12h prior to reuse. The evaluation procedure consisted of using extracts of naturallycontaminated peanut confection (4 replicates), aflatoxin-free peanut confection (duplicates), and aflatoxin-free peanut confection sample spiked with the 4 aflatoxins (AFT) at 3 levels in 4 replicates. Each day, 18 test extracts were analyzed using 18 designated IACs. After each use, the IACs were regenerated and reused for corresponding test extracts on the following day. This procedure was repeated daily over the course of 9days. Analytical steps included passing the test extracts through the IACs, washing the columns with water, and eluting AFT with methanol. The eluates were diluted with water and were subjected to reversed phase LC separation, post-column photochemical derivatization and fluorescence detection. After eluting AFT, IACs were immediately regenerated by washing with phosphate buffer solution and storing overnight at 8°C for re-use the following day. Results were analyzed using ANOVA and Tukey tests. The numbers of reuse varied for each AF: For AFB1 AFB2, AFG1and AFG2 could be reused for 9, 6, 6 and 0 times, respectively. According to AOAC method performance criteria, recoveries ranging from 70% to 125% are considered acceptable at the spiking levels used in this study.

  1. The effect of raw material contamination with mycotoxins on the composition of alcoholic fermentation volatile by-products in raw spirits.

    PubMed

    Kłosowski, Grzegorz; Mikulski, Dawid

    2010-12-01

    The effects of the mycotoxins, aflatoxin B(1), B(2), G(1), G(2) (AF), ochratoxin A, (OTA), zearalenone (ZEA), deoxynivalenol (DON), and fumonisin B(1) (FB(1)) added to corn grain mashes on the composition of fermentation volatile by-products in raw spirits were determined. Except for FB(1), the mycotoxins increased acetaldehyde concentration in the obtained spirits from about 30% to 100% in relation to the control set (30.9+/-1.0mg of acetaldehyde/L EtOH). The largest effect was observed for OTA and AF contaminations (65.9+/-5.9 and 62.4+/-5.0mg/L EtOH, respectively). At the concentrations used (ppb): FB(1), 1875; FB(2), 609; FB(3), 195; DON, 2274; ZEA, 352; AFB(1), 11.65; AFB(2), 12.6; AFG(1), 12.34; AFG(2), 12.04; OTA, 177.5, the mycotoxins did not have a significant effect on the total level of higher alcohols in distillates. As compared to the control, contamination with OTA and FB(1) decreased the 3-methyl-1-butanol concentration by 11.2% and 12.6% respectively, whereas AF decreased the 2-methyl-1-butanol concentration by 14.9%. The mycotoxins AF, ZEA, FB(1), had no significant effect on the concentration of total esters. Whereas OTA caused twofold higher esters concentration in the distillates, DON lowered esters concentration by 32% as compared to control. Presented results show that quantitative changes in composition of volatile fermentation by-products in raw spirits can be related to the presence of increased level of mycotoxins in raw material, especially in the absence of other identifiable factors disturbing the normal course of process.

  2. The antioxidant effects of pumpkin seed oil on subacute aflatoxin poisoning in mice.

    PubMed

    Eraslan, Gökhan; Kanbur, Murat; Aslan, Öznur; Karabacak, Mürsel

    2013-12-01

    This study was aimed at the investigation of the antioxidant effect of pumpkin seed oil against the oxidative stress-inducing potential of aflatoxin. For this purpose, 48 male BALB/c mice were used. Four groups, each comprising 12 mice, were established. Group 1 was maintained as the control group. Group 2 was administered with pumpkin seed oil alone at a dose of 1.5 mL/kg.bw/day (∼1375mg/kg.bw/day). Group 3 received aflatoxin (82.45% AFB1 , 10.65% AFB2 , 4.13% AFG1, and 2.77% AFG2 ) alone at a dose of 625 μg/kg.bw/day. Finally, group 4 was given both 1.5 mL/kg.bw/day pumpkin seed oil and 625 μg/kg.bw/day aflatoxin. All administrations were oral, performed with the aid of a gastric tube and continued for a period of 21 days. At the end of day 21, the liver, lungs, kidneys, brain, heart, and spleen of the animals were excised, and the extirpated tissues were homogenized appropriately. Malondialdehyde (MDA) levels and catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were determined in tissue homogenates. In conclusion, it was determined that aflatoxin exhibited adverse effects on most of the oxidative stress markers. The administration of pumpkin seed oil diminished aflatoxin-induced adverse effects. In other words, the values of the group, which was administered with both aflatoxin and pumpkin seed oil, were observed to have drawn closer to the values of the control group.

  3. Assessment of Mycotoxin Exposure in Côte d’ivoire (Ivory Coast) Through Multi-Biomarker Analysis and Possible Correlation with Food Consumption Patterns

    PubMed Central

    Kouadio, James Halbin; Lattanzio, Veronica M. T.; Ouattara, Djeneba; Kouakou, Brou; Visconti, Angelo

    2014-01-01

    Scope: The aim of the presented study was to investigate the mycotoxin exposure of Ivorian population related to the consumption patterns of maize, peanuts, millet, and cassava product (attiéké). Materials and Methods: Maize flour samples (n = 51) were purchased from all Abidjan local markets, in the south of Ivory Coast, and urine (n = 99) was collected during the same reference period (July–September 2011) from volunteers living in Abidjan and Daloa cities. Reversed-phase liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry (LC-ESI-MS/MS) was used to analyze aflatoxins (AFB1, AFB2, AFG1, and AFG2), ochratoxin A (OTA), fumonisins (FB1, FB2), deoxynivalenol (DON), zearalenone (ZEA), and T-2 and HT-2 toxins in maize flour samples, and their relevant biomarkers (AFM1, DON, DON + de-epoxydeoxynivalenol (DOM-1), FB1, α-zearalenol (ZOL), β-ZOL, and OTA) in urine samples. Results: Critical maize contamination was observed by AFs occurrence (total AFs 4.5 – 330.0 μg/kg) while OTA was found in 13% of samples analyzed. AFM1 was detected in 40% of urines samples (0.06 – 14.11 ng/ml), OTA in 37% (0.01 – 0.42 ng/ml), FB1 in 27% (0.07 to 15.31 ng/ml) and, DON was found in 21% of samples at levels up to 10.0 ng/ml. The correlation coefficients (R2) obtained by plotting the percentage of biomarker occurrence (positive samples) versus the frequency of food consumption revealed maize, peanuts, millet and attiéké were strongly linked to AFB1 and OTA exposure with values of R2 ranged from 0.462 to 0.956. Conclusion: The present study provided data on mycotoxin risk in Ivory Coast, revealing a frequent co-exposure to the major mycotoxins such as AFs, OTA, and fumonisins, which appeared to be related to the frequency of peanuts, maize, millet and attiéké consumption. PMID:25948962

  4. Application of magnetic solid phase extraction for separation and determination of aflatoxins B ₁ and B₂ in cereal products by high performance liquid chromatography-fluorescence detection.

    PubMed

    Hashemi, Mahdi; Taherimaslak, Zohreh; Rashidi, Somayeh

    2014-06-01

    A simple and sensitive method based on the magnetic solid phase extraction with modified magnetic nanoparticles followed by high performance liquid chromatography with fluorescence detection has been developed for extraction and determination of aflatoxins B1 (AFB1) and B2 (AFB2) in cereal products. Magnetic nanoparticle coated with 3-(trimethoxysilyl)-1-propanthiol (TMSPT) and modified with 2-amino-5-mercapto-1,3,4-thiadiazole (AMT) was used as an antibody-free adsorbent. Under the optimal conditions, the calibration curves for AFB1 and AFB2 were linear in the ranges of 0.2-15 μg L(-1) and 0.04-3 μg L(-1), respectively. Detection limit was 0.041 μg L(-1) for AFB1 and 0.013 μg L(-1) for AFB2. The proposed method was successfully applied to the determination of AFB1 and AFB2 in spiked corn and rice samples with an average recovery of 93.5%. The results demonstrated that the developed method is simple, rapid, inexpensive, accurate and remarkably free from interference effects.

  5. Distribution of aflatoxins in product and by-products during glucose production from contaminated corn.

    PubMed

    Aly, Soher E

    2002-10-01

    Aflatoxins are known to be hepatotoxic, carcinogenic, and teratogenic. A positive correlation has been established between the consumption of aflatoxin-contaminated foods and the increased incidence of liver cancer worldwide. A survey of Egyptian corn and corn-based products and by-products shows that the majority of the samples had higher limits of aflatoxin. We have conducted experiments to determine the fate and distribution of aflatoxin during wet-milling process fractions and investigate the aflatoxin destruction during starch conversion to glucose syrup. The present results showed that about half of the aflatoxin content (48.1%) in the infected corn grain was found to be lost in steep liquor, depending upon the aflatoxin type, arranged in the order G1 > G2 > B1 > B2. After wet-milling aflatoxins were distributed into starch, gluten, fiber, and germ. Gluten, fiber, and germ were the most highly contaminated fractions. The loss of aflatoxin during process of starches reached 54.4% in steep water and water process. Although the gluten fraction represents only 9.6% of corn, the higher percentage (25.3%) of aflatoxin was found in this fraction, the fiber and germ account for nearly 29% of the milled corn and contain 11.6% of the aflatoxin. On the other hand, 8.7% of the total aflatoxins in start corn was found in starch fraction which accounts 61% of the milled corn. Aflatoxins G1 and G2 were found lost in higher concentrations compared to the aflatoxin B1 and B2. A higher percentage of AfG1 (86.35%) and AfG2 (78.36%) and a lower percentage of AfB1 (16.3%) and AfB2 (14.7%) were found in starch fraction. The conversion percent of contaminated starch was 89.5% compared with control starch. It can be concluded that aflatoxins were destroyed during starch conversion. Consequently, glucose syrup produced from contaminated starch was found aflatoxin-free.

  6. Aflatoxins and heavy metals in animal feed in Iran.

    PubMed

    Eskandari, M H; Pakfetrat, S

    2014-01-01

    The occurrence of aflatoxin (aflatoxin B1, aflatoxin B2, aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2)) and heavy metal (Pb, Cd, As and Hg) contamination was determined in 40 industrially produced animal feed samples which were collected from the southwest of Iran. The results indicated that 75% of samples were contaminated by four aflatoxins and the level of AFB1 and sum of aflatoxins were higher than the permissible maximum levels in Iran (5 and 20 µg kg(-1), respectively) in all feed samples. A positive correlation was found between four types of aflatoxins in all the tested samples (p < 0.01) and the positive correlation between AFG1 and AFG2 was significant (r(2) = 0.708). All feed samples had lead concentrations lower than the maximum EU limit, while 5%, 17% and 42.5% of feed samples had As, Cd and Hg concentrations higher than the maximum limits, respectively.

  7. Mycotoxin Contamination in Sugarcane Grass and Juice: First Report on Detection of Multiple Mycotoxins and Exposure Assessment for Aflatoxins B1 and G1 in Humans

    PubMed Central

    Abdallah, Mohamed F.; Krska, Rudolf; Sulyok, Michael

    2016-01-01

    This study was conducted to investigate the natural co-occurrence of multiple toxic fungal and bacterial metabolites in sugarcane grass and juice intended for human consumption in Upper Egypt. Quantification of the target analytes has been done using the “dilute and shoot” approach followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total number of 29 and 33 different metabolites were detected in 21 sugarcane grass and 40 juice samples, respectively, with a trend of concentrations being higher in grass than in juice. Among the regulated mycotoxins, only aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1) were detected. The prevalence of AFB1 was in 48% of grass samples and in 58% of juice with a maximum concentration of 30.6 μg/kg and 2.10 μg/kg, respectively. AFG1 was detected in 10% of grass samples (7.76 μg/kg) and 18% of juice samples (34 μg/kg). Dietary exposure was assessed using a juice frequency questionnaire of adult inhabitants in Assiut City. The assessment revealed different levels of exposure to AFB1 between males and females in winter and summer seasons. The estimated seasonal exposure ranged from 0.20 to 0.40 ng/kg b.w./day in winter and from 0.38 to 0.90 ng/kg b.w./day in summer. PMID:27869706

  8. Degradation of aflatoxin B1 during the fermentation of alcoholic beverages.

    PubMed

    Inoue, Tomonori; Nagatomi, Yasushi; Uyama, Atsuo; Mochizuki, Naoki

    2013-06-28

    Aflatoxin B1 (AFB1) is a contaminant of grain and fruit and has one of the highest levels of carcinogenicity of any natural toxin. AFB1 and the fungi that produce it can also contaminate the raw materials used for beer and wine manufacture, such as corn and grapes. Therefore, brewers must ensure strict monitoring to reduce the risk of contamination. In this study, the fate of AFB1 during the fermentation process was investigated using laboratory-scale bottom and top beer fermentation and wine fermentation. During fermentation, cool wort beer samples and wine must samples were artificially spiked with AFB1 and the levels of AFB1 remaining after fermentation were analyzed. AFB1 levels were unchanged during both types of fermentation used for beer but were reduced to 30% of their initial concentration in wine. Differential analysis of the spiked and unspiked wine samples showed that the degradation compound was AFB2a, a hydrated derivative of AFB1. Thus, the results showed that the risk of AFB1 carryover was still present for both types of beer fermentation but was reduced in the case of wine fermentation because of hydration.

  9. Inhibitory effects of Satureja hortensis L. essential oil on growth and aflatoxin production by Aspergillus parasiticus.

    PubMed

    Razzaghi-Abyaneh, Mehdi; Shams-Ghahfarokhi, Masoomeh; Yoshinari, Tomoya; Rezaee, Mohammad-Bagher; Jaimand, Kamkar; Nagasawa, Hiromichi; Sakuda, Shohei

    2008-04-30

    In an effort to screen the essential oils of some Iranian medicinal plants for novel aflatoxin (AF) inhibitors, Satureja hortensis L. was found as a potent inhibitor of aflatoxins B1 (AFB1) and G1(AFG1) production by Aspergillus parasiticus NRRL 2999. Fungal growth was also inhibited in a dose-dependent manner. Separation of the plant inhibitory substance(s) was achieved using initial fractionation of its effective part (leaf essential oil; LEO) by silica gel column chromatography and further separation by reverse phase-high performance liquid chromatography (RP-HPLC). These substances were finally identified as carvacrol and thymol, based on the interpretation of 1H and 13C NMR spectra. Microbioassay (MBA) on cell culture microplates contained potato-dextrose broth (PDB) medium (4 days at 28 degrees C) and subsequent analysis of cultures with HPLC technique revealed that both carvacrol and thymol were able to effectively inhibit fungal growth, AFB1 and AFG1 production in a dose-dependent manner at all two-fold concentrations from 0.041 to 1.32 mM. The IC50 values for growth inhibition were calculated as 0.79 and 0.86 mM for carvacrol and thymol, while for AFB1 and AFG1, it was reported as 0.50 and 0.06 mM for carvacrol and 0.69 and 0.55 mM for thymol. The results obtained in this study clearly show a new biological activity for S. hortensis L. as strong inhibition of aflatoxin production by A. parasiticus. Carvacrol and thymol, the effective constituents of S. hortensis L., may be useful to control aflatoxin contamination of susceptible crops in the field.

  10. Modulation of macrophage activity by aflatoxins B1 and B2 and their metabolites aflatoxins M1 and M2.

    PubMed

    Bianco, G; Russo, R; Marzocco, S; Velotto, S; Autore, G; Severino, L

    2012-05-01

    Aflatoxins are natural contaminants frequently found both in food and feed. Many of them exert immunomodulatory properties in mammals; therefore, the aim of the current study was to investigate immune-effects of AFB1, AFB2, AFM1 and AFM2, alone and differently combined, in J774A.1 murine macrophages. MTT assay showed that AFB1, alone and combined with AFB2, possess antiproliferative activity only at the highest concentration; such effect was not shown by their hydroxylated metabolites, AFM1 and AFM2, respectively. However, the immunotoxic effects of the aflatoxins evaluated in the current study may be due to the inhibition of production of active oxygen metabolites such as NO. Cytofluorimetric assay in macrophages exposed to aflatoxins (10-100 μM) revealed that their cytoxicity is not related to apoptotic pathways. Nevertheless, a significant increase of the S phase cell population accompanied by a decrease in G0/G1 phase cell population was observed after AFB1 treatment. In conclusion, the results of the current study suggest that aflatoxins could compromise the macrophages functions; in particular, co-exposure to AFB1, AFB2, AFM1 and AFM2 may exert interactions which can significantly affect immunoreactivity.

  11. Shaw Air Force Base Infrastructure Project Environmental Assessment

    DTIC Science & Technology

    2008-09-01

    environmental impact statement (E ) is n warranted. DATE This page is intentionally blank. Final Shaw Air Force Base Infrastructure...AFB viii This page is intentionally blank. Purpose and Need EA for Infrastructure at Shaw AFB 1-1 Shaw AFB Infrastructure EA Chapter 1.0... intentionally blank. Description of the Proposed Action and Alternatives EA for Infrastructure at Shaw AFB 2-1 2.0 DESCRIPTION OF THE PROPOSED

  12. Aflatoxin B1 Degradation by a Pseudomonas Strain

    PubMed Central

    Sangare, Lancine; Zhao, Yueju; Folly, Yawa Minnie Elodie; Chang, Jinghua; Li, Jinhan; Selvaraj, Jonathan Nimal; Xing, Fuguo; Zhou, Lu; Wang, Yan; Liu, Yang

    2014-01-01

    Aflatoxin B1 (AFB1), one of the most potent naturally occurring mutagens and carcinogens, causes significant threats to the food industry and animal production. In this study, 25 bacteria isolates were collected from grain kernels and soils displaying AFB1 reduction activity. Based on its degradation effectiveness, isolate N17-1 was selected for further characterization and identified as Pseudomonas aeruginosa. P. aeruginosa N17-1 could degrade AFB1, AFB2 and AFM1 by 82.8%, 46.8% and 31.9% after incubation in Nutrient Broth (NB) medium at 37 °C for 72 h, respectively. The culture supernatant of isolate N17-1 degraded AFB1 effectively, whereas the viable cells and intra cell extracts were far less effective. Factors influencing AFB1 degradation by the culture supernatant were investigated. Maximum degradation was observed at 55 °C. Ions Mn2+ and Cu2+ were activators for AFB1 degradation, however, ions Mg2+, Li+, Zn2+, Se2+, Fe3+ were strong inhibitors. Treatments with proteinase K and proteinase K plus SDS significantly reduced the degradation activity of the culture supernatant. No degradation products were observed based on preliminary LC-QTOF/MS analysis, indicating AFB1 was metabolized to degradation products with chemical properties different from that of AFB1. The results indicated that the degradation of AFB1 by P. aeruginosa N17-1 was enzymatic and could have a great potential in industrial applications. This is the first report indicating that the isolate of P. aeruginosa possesses the ability to degrade aflatoxin. PMID:25341538

  13. Structural Analysis and Biological Toxicity of Aflatoxins B1 and B2 Degradation Products Following Detoxification by Ocimum basilicum and Cassia fistula Aqueous Extracts.

    PubMed

    Iram, Wajiha; Anjum, Tehmina; Iqbal, Mazhar; Ghaffar, Abdul; Abbas, Mateen; Khan, Abdul Muqeet

    2016-01-01

    This study showed the comparison between Ocimum basilicum and Cassia fistula (leaves and branch) aqueous extracts for their ability to detoxify of aflatoxins B1 and B2 (AFB1; 100 μg L(-1) and AFB2; 50 μg L(-1)) by In Vitro assays and decontamination studies. Results indicated that O. basilicum leaves extract was found to be highly significant (P < 0.05) in degrading AFB1 and AFB2, i.e., 90.4 and 88.6%, respectively. However, O. basilicum branch, C. fistula leaves and branch extracts proved to be less efficient in degrading these aflatoxins, under optimized conditions, i.e., pH 8, temperature 30°C and incubation period of 72 h. Moreover the antifungal activity of these plants extracts were also tested. The findings depicted that O. basilicum leaves extract showed maximum growth inhibition of aflatoxigenic isolates, i.e., 82-87% as compared to other tested plants extracts. The structural elucidation of degraded toxin products by LCMS/MS analysis showed that nine degraded products of AFB1 and AFB2 were formed. MS/MS spectra showed that most of the products were formed by the removal of double bond in the terminal furan ring and modification of lactone group indicating less toxicity as compared to parent compounds. Brine shrimps bioassay further confirmed the low toxicity of degraded products, showing that O. basilicum leaves extract can be used as an effective tool for the detoxification of aflatoxins.

  14. Structural Elucidation and Toxicity Assessment of Degraded Products of Aflatoxin B1 and B2 by Aqueous Extracts of Trachyspermum ammi.

    PubMed

    Iram, Wajiha; Anjum, Tehmina; Iqbal, Mazhar; Ghaffar, Abdul; Abbas, Mateen

    2016-01-01

    In this study aqueous extract of seeds and leaves of Trachyspermum ammi were evaluated for their ability to detoxify aflatoxin B1 and B2 (AFB1; 100 μg L(-1) and AFB2; 50 μg L(-1)) by in vitro and in vivo assays. Results indicated that T. ammi seeds extract was found to be significant (P < 0.05) in degrading AFB1 and AFB2 i.e., 92.8 and 91.9% respectively. However, T. ammi leaves extract proved to be less efficient in degrading these aflatoxins, under optimized conditions i.e., pH 8, temperature 30°C and incubation period of 72 h. The structural elucidation of degraded toxin products by LCMS/MS analysis showed that eight degraded products of AFB1 and AFB2 were formed. MS/MS spectra showed that most of the products were formed by the removal of double bond in the terminal furan ring and modification of lactone group indicating less toxicity as compared to parent compounds. Brine shrimps bioassay further confirmed the low toxicity of degraded products, showing that T. ammi seeds extract can be used as an effective tool for the detoxification of aflatoxins.

  15. Mass spectrometric identification and toxicity assessment of degraded products of aflatoxin B1 and B2 by Corymbia citriodora aqueous extracts

    PubMed Central

    Iram, Wajiha; Anjum, Tehmina; Iqbal, Mazhar; Ghaffar, Abdul; Abbas, Mateen

    2015-01-01

    This study explores the detoxification potential of Corymbia citriodora plant extracts against aflatoxin B1 and B2 (AFB1; 100 μg L−1 and AFB2; 50 μg L−1) in In vitro and In vivo assays. Detoxification was qualitatively and quantitatively analyzed by TLC and HPLC, respectively. The study was carried out by using different parameters of optimal temperature, pH and incubation time period. Results indicated that C. citriodora leaf extract(s) more effectively degrade AFB1 and AFB2 i.e. 95.21% and 92.95% respectively than C. citriodora branch extract, under optimized conditions. The structural elucidation of degraded toxin products was done by LCMS/MS analysis. Ten degraded products of AFB1 and AFB2 and their fragmentation pathways were proposed based on molecular formulas and MS/MS spectra. Toxicity of these degraded products was significantly reduced as compared to that of parent compounds because of the removal of double bond in the terminal furan ring. The biological toxicity of degraded toxin was further analyzed by brine shrimps bioassay, which showed that only 17.5% mortality in larvae was recorded as compared to untreated toxin where 92.5% mortality was observed after 96hr of incubation. Therefore, our finding suggests that C. citriodora leaf extract can be used as an effective tool for the detoxification of aflatoxins. PMID:26423838

  16. Structural Elucidation and Toxicity Assessment of Degraded Products of Aflatoxin B1 and B2 by Aqueous Extracts of Trachyspermum ammi

    PubMed Central

    Iram, Wajiha; Anjum, Tehmina; Iqbal, Mazhar; Ghaffar, Abdul; Abbas, Mateen

    2016-01-01

    In this study aqueous extract of seeds and leaves of Trachyspermum ammi were evaluated for their ability to detoxify aflatoxin B1 and B2 (AFB1; 100 μg L−1 and AFB2; 50 μg L−1) by in vitro and in vivo assays. Results indicated that T. ammi seeds extract was found to be significant (P < 0.05) in degrading AFB1 and AFB2 i.e., 92.8 and 91.9% respectively. However, T. ammi leaves extract proved to be less efficient in degrading these aflatoxins, under optimized conditions i.e., pH 8, temperature 30°C and incubation period of 72 h. The structural elucidation of degraded toxin products by LCMS/MS analysis showed that eight degraded products of AFB1 and AFB2 were formed. MS/MS spectra showed that most of the products were formed by the removal of double bond in the terminal furan ring and modification of lactone group indicating less toxicity as compared to parent compounds. Brine shrimps bioassay further confirmed the low toxicity of degraded products, showing that T. ammi seeds extract can be used as an effective tool for the detoxification of aflatoxins. PMID:27064492

  17. MicroRNA Responses to the Genotoxic Carcinogens Aflatoxin B1 and Benzo[a]pyrene in Human HepaRG Cells.

    PubMed

    Marrone, April K; Tryndyak, Volodymyr; Beland, Frederick A; Pogribny, Igor P

    2016-02-01

    Recent advances in toxicogenomics present an opportunity to develop new in vitro testing methodologies to identify human carcinogens. We have investigated microRNA expression responses to the treatment of human liver HepaRG cells with the human genotoxic carcinogens aflatoxin B1 (AFB1) and benzo[a]pyrene (B[a]P), and the structurally similar compounds aflatoxin B2 (AFB2) and benzo[e]pyrene (B[e]P) that exhibit minimal carcinogenic potential. We demonstrate that treatment of HepaRG cells with AFB1 or B[a]P resulted in specific changes in the expression of miRNAs as compared with their non-carcinogenic analogues, particularly in a marked over-expression of miR-410. An additional novel finding is the dose- and time-dependent inhibition of miR-122 in AFB1-treated HepaRG cells. Mechanistically, the AFB1-induced down-regulation of miR-122 was attributed to inhibition of the HNF4A/miR-122 regulatory pathway. These results demonstrate that HepaRG cells can be used to investigate miRNA responses to xenobiotic exposure, and illustrate the existence of early non-genotoxic events, in addition to a well-established genotoxic mode of action changes, in the mechanism of AFB1 and B[a]P carcinogenicity.

  18. Analysis of the aflatoxin AFB1 from corn by direct analysis in real time - mass spectrometry (DART-MS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Direct analysis in real time (DART) ionization coupled to a high resolution mass spectrometer (MS) was used for screening of aflatoxins from a variety of surfaces and the rapid quantitative analysis of aflatoxins extracted from corn. Sample preparation procedure and instrument parameter settings wer...

  19. Adverse Outcome Pathway (AOP) for a Mutagenic Mode of Action for Cancer: AFB1 and Hepatocellular Carcinoma (HCC)

    EPA Science Inventory

    AOPs provide a framework to describe a sequence of measureable key events (KEs), beginning with a molecular initiating event (MIE), followed by a series of identified KEs linked to one another by KE Relationships (KERs), all anchored by a specific adverse outcome (AO). Each KE/KE...

  20. Structural Analysis and Biological Toxicity of Aflatoxins B1 and B2 Degradation Products Following Detoxification by Ocimum basilicum and Cassia fistula Aqueous Extracts

    PubMed Central

    Iram, Wajiha; Anjum, Tehmina; Iqbal, Mazhar; Ghaffar, Abdul; Abbas, Mateen; Khan, Abdul Muqeet

    2016-01-01

    This study showed the comparison between Ocimum basilicum and Cassia fistula (leaves and branch) aqueous extracts for their ability to detoxify of aflatoxins B1 and B2 (AFB1; 100 μg L-1 and AFB2; 50 μg L-1) by In Vitro assays and decontamination studies. Results indicated that O. basilicum leaves extract was found to be highly significant (P < 0.05) in degrading AFB1 and AFB2, i.e., 90.4 and 88.6%, respectively. However, O. basilicum branch, C. fistula leaves and branch extracts proved to be less efficient in degrading these aflatoxins, under optimized conditions, i.e., pH 8, temperature 30°C and incubation period of 72 h. Moreover the antifungal activity of these plants extracts were also tested. The findings depicted that O. basilicum leaves extract showed maximum growth inhibition of aflatoxigenic isolates, i.e., 82–87% as compared to other tested plants extracts. The structural elucidation of degraded toxin products by LCMS/MS analysis showed that nine degraded products of AFB1 and AFB2 were formed. MS/MS spectra showed that most of the products were formed by the removal of double bond in the terminal furan ring and modification of lactone group indicating less toxicity as compared to parent compounds. Brine shrimps bioassay further confirmed the low toxicity of degraded products, showing that O. basilicum leaves extract can be used as an effective tool for the detoxification of aflatoxins. PMID:27471501

  1. Novel Aflatoxin-Degrading Enzyme from Bacillus shackletonii L7

    PubMed Central

    Xu, Liang; Eisa Ahmed, Mohamed Farah; Sangare, Lancine; Zhao, Yueju; Selvaraj, Jonathan Nimal; Xing, Fuguo; Wang, Yan; Yang, Hongping; Liu, Yang

    2017-01-01

    Food and feed contamination by aflatoxin (AF)B1 has adverse economic and health consequences. AFB1 degradation by microorganisms or microbial enzymes provides a promising preventive measure. To this end, the present study tested 43 bacterial isolates collected from maize, rice, and soil samples for AFB1-reducing activity. The higher activity was detected in isolate L7, which was identified as Bacillus shackletonii. L7 reduced AFB1, AFB2, and AFM1 levels by 92.1%, 84.1%, and 90.4%, respectively, after 72 h at 37 °C. The L7 culture supernatant degraded more AFB1 than viable cells and cell extracts; and the degradation activity was reduced from 77.9% to 15.3% in the presence of proteinase K and sodium dodecyl sulphate. A thermostable enzyme purified from the boiled supernatant was designated as Bacillus aflatoxin-degrading enzyme (BADE). An overall 9.55-fold purification of BADE with a recovery of 39.92% and an activity of 3.85 × 103 U·mg−1 was obtained using chromatography on DEAE-Sepharose. BADE had an estimated molecular mass of 22 kDa and exhibited the highest activity at 70 °C and pH 8.0, which was enhanced by Cu2+ and inhibited by Zn2+, Mn2+, Mg2+, and Li+. BADE is the major protein involved in AFB1 detoxification. This is the first report of a BADE isolated from B. shackletonii, which has potential applications in the detoxification of aflatoxins during food and feed processing. PMID:28098812

  2. The role of pre-symbiotic auxin signaling in ectendomycorrhiza formation between the desert truffle Terfezia boudieri and Helianthemum sessiliflorum.

    PubMed

    Turgeman, Tidhar; Lubinsky, Olga; Roth-Bejerano, Nurit; Kagan-Zur, Varda; Kapulnik, Yoram; Koltai, Hinanit; Zaady, Eli; Ben-Shabat, Shimon; Guy, Ofer; Lewinsohn, Efraim; Sitrit, Yaron

    2016-05-01

    The ectendomycorrhizal fungus Terfezia boudieri is known to secrete auxin. While some of the effects of fungal auxin on the plant root system have been described, a comprehensive understanding is still lacking. A dual culture system to study pre mycorrhizal signal exchange revealed previously unrecognized root-fungus interaction mediated by the fungal auxin. The secreted fungal auxin induced negative taproot gravitropism, attenuated taproot growth rate, and inhibited initial host development. Auxin also induced expression of Arabidopsis carriers AUX1 and PIN1, both of which are involved in the gravitropic response. Exogenous application of auxin led to a root phenotype, which fully mimicked that induced by ectomycorrhizal fungi. Co-cultivation of Arabidopsis auxin receptor mutants tir1-1, tir1-1 afb2-3, tir1-1 afb1-3 afb2-3, and tir1-1 afb2-3 afb3-4 with Terfezia confirmed that auxin induces the observed root phenotype. The finding that auxin both induces taproot deviation from the gravity axis and coordinates growth rate is new. We propose a model in which the fungal auxin induces horizontal root development, as well as the coordination of growth rates between partners, along with the known auxin effect on lateral root induction that increases the availability of accessible sites for colonization at the soil plane of fungal spore abundance. Thus, the newly observed responses described here of the root to Terfezia contribute to a successful encounter between symbionts.

  3. Biological control of AFB1-producing Aspergillus section Flavi strains isolated from brewer's grains, alternative feed intended for swine production in Argentina.

    PubMed

    Asurmendi, Paula; García, María J; Ruíz, Francisco; Dalcero, Ana; Pascual, Liliana; Barberis, Lucila

    2016-07-02

    The aim of the present study was to investigate the inhibitory activity of lactic acid bacteria (LAB) isolated from brewer's grains on Aspergillus section Flavi growth and aflatoxin B1 production. The Aspergillus strains tested were inhibited by all the LAB strains assayed. The isolates Lactobacillus brevis B20, P. pentosaceus B86, Lactococcus lactis subsp. lactis B87, L. brevis B131, and Lactobacillus sp. B144 completely suppressed the fungal growth and reduced aflatoxin B1 production. In conclusion, LAB isolated from brewer's grains show a high inhibitory activity on fungal growth and aflatoxin biosynthesis by Aspergillus flavus and Aspergillus parasiticus. Further studies must be conducted to evaluate the success of in vitro assays under food environment conditions and to elucidate the antifungal mechanism of these strains.

  4. Mycotoxin and fungicide residues in wheat grains from fungicide-treated plants measured by a validated LC-MS method.

    PubMed

    da Luz, Suzane Rickes; Pazdiora, Paulo Cesar; Dallagnol, Leandro José; Dors, Giniani Carla; Chaves, Fábio Clasen

    2017-04-01

    Wheat (Triticum aestivum) is an annual crop, cultivated in the winter and spring and susceptible to several pathogens, especially fungi, which are managed with fungicides. It is also one of the most consumed cereals, and can be contaminated by mycotoxins and fungicides. The objective of this study was to validate an analytical method by LC-MS for simultaneous determination of mycotoxins and fungicide residues in wheat grains susceptible to fusarium head blight treated with fungicides, and to evaluate the relationship between fungicide application and mycotoxin production. All parameters of the validated analytical method were within AOAC and ANVISA limits. Deoxynivalenol was the prevalent mycotoxin in wheat grain and epoxiconazole was the fungicide residue found in the highest concentration. All fungicidal treatments induced an increase in AFB2 production when compared to the control (without application). AFB1 and deoxynivalenol, on the contrary, were reduced in all fungicide treatments compared to the control.

  5. Chicken fetal liver DNA damage and adduct formation by activation-dependent DNA-reactive carcinogens and related compounds of several structural classes.

    PubMed

    Williams, Gary M; Duan, Jian-Dong; Brunnemann, Klaus D; Iatropoulos, Michael J; Vock, Esther; Deschl, Ulrich

    2014-09-01

    The chicken egg genotoxicity assay (CEGA), which utilizes the liver of an intact and aseptic embryo-fetal test organism, was evaluated using four activation-dependent DNA-reactive carcinogens and four structurally related less potent carcinogens or non-carcinogens. In the assay, three daily doses of test substances were administered to eggs containing 9-11-day-old fetuses and the fetal livers were assessed for two endpoints, DNA breaks using the alkaline single cell gel electrophoresis (comet) assay and DNA adducts using the (32)P-nucleotide postlabeling (NPL) assay. The effects of four carcinogens of different structures requiring distinct pathways of bioactivation, i.e., 2-acetylaminofluorene (AAF), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and diethylnitrosamine (DEN), were compared with structurally related non-carcinogens fluorene (FLU) and benzo[e]pyrene (B[e]P) or weak carcinogens, aflatoxin B2 (AFB2) and N-nitrosodiethanolamine (NDELA). The four carcinogens all produced DNA breaks at microgram or low milligram total doses, whereas less potent carcinogens and non-carcinogens yielded borderline or negative results, respectively, at higher doses. AAF and B[a]P produced DNA adducts, whereas none was found with the related comparators FLU or B[e]P, consistent with comet results. DEN and NDELA were also negative for adducts, as expected in the case of DEN for an alkylating agent in the standard NPL assay. Also, AFB1 and AFB2 were negative in NPL, as expected, due to the nature of ring opened aflatoxin adducts, which are resistant to enzymatic digestion. Thus, the CEGA, using comet and NPL, is capable of detection of the genotoxicity of diverse DNA-reactive carcinogens, while not yielding false positives for non-carcinogens.

  6. Surveys of rice sold in Canada for aflatoxins, ochratoxin A and fumonisins

    PubMed Central

    Bansal, J.; Pantazopoulos, P.; Tam, J.; Cavlovic, P.; Kwong, K.; Turcotte, A.-M.; Lau, B.P.-Y.; Scott, P.M.

    2011-01-01

    Approximately 200 samples of rice (including white, brown, red, black, basmati and jasmine, as well as wild rice) from several different countries, including the United States, Canada, Pakistan, India and Thailand, were analysed for aflatoxins, ochratoxin A (OTA) and fumonisins by separate liquid Chromatographic methods in two different years. The mean concentrations for aflatoxin B1 (AFB1) were 0.19 and 0.17 ng g−1 with respective positive incidences of 56% and 43% (≥ the limit of detection (LOD) of 0.002 ng g−1). Twenty-three samples analysed in the second year also contained aflatoxin B2 (AFB2) at levels ≥LOD of 0.002 ng g−1 The five most contaminated samples in each year contained 1.44–7.14 ng AFB1 g−1 (year 1) and 1.45–3.48 ng AFB1 g−1 (year 2); they were mostly basmati rice from India and Pakistan and black and red rice from Thailand. The average concentrations of ochratoxin A (OTA) were 0.05 and 0.005 ng g−1 in year 1 and year 2, respectively; incidences of samples containing ≥LOD of 0.05 ng g−1 were 43% and 1%, respectively, in the 2 years. All positive OTA results were confirmed by LC-MS/MS. For fumonisins, concentrations of fumonisin B1 (FB1) averaged 4.5 ng g−1 in 15 positive samples (≥0.7 ng g−1) from year 1 (n = 99); fumonisin B2 (FB2) and fumonisin B3 (FB3) were also present (≥1 ng g−1). In the second year there was only one positive sample (14 ng g−1 FB1) out of 100 analysed. All positive FB1 results were confirmed by LC-MS/MS. PMID:21623501

  7. Present and future directions of translational research on aflatoxin and hepatocellular carcinoma. A review.

    PubMed

    Wogan, Gerald N; Kensler, Thomas W; Groopman, John D

    2012-01-01

    The aflatoxins were discovered in toxic peanut meal causing "turkey X" disease, which killed large numbers of turkey poults, ducklings and chicks in the UK in the early 1960s. Extracts of toxic feed induced the symptoms in experimental animals, and purified metabolites with properties identical to aflatoxins B(1) and G(1) (AFB(1) and AFG(1)) were isolated from Aspergillus flavus cultures. Structure elucidation of aflatoxin B(1) was accomplished and confirmed by total synthesis in 1963. AFB(1) is a potent liver carcinogen in rodents, non-human primates, fish and birds, operating through a genotoxic mechanism involving metabolic activation to an epoxide, formation of DNA adducts and, in humans, modification of the p53 gene. Aflatoxins are unique among environmental carcinogens, in that elucidation of their mechanisms of action combined with molecular epidemiology provides a foundation for quantitative risk assessment; extensive evidence confirms that contamination of the food supply by AFB(1) puts an exposed population at increased risk of developing hepatocellular carcinoma (HCC). Molecular biomarkers to quantify aflatoxin exposure in individuals were essential to link aflatoxin exposure with liver cancer risk. Biomarkers were validated in populations with high HCC incidence in China and The Gambia, West Africa; urinary AFB(1)-N (7)-Guanine excretion was linearly related to aflatoxin intake, and levels of aflatoxin-serum albumin adducts also reflected aflatoxin intake. Two major cohort studies employing aflatoxin biomarkers identified their causative role in HCC etiology. Results of a study in Shanghai men strongly support a causal relationship between HCC risk and the presence of biomarkers for aflatoxin and HBV infection, and also show that the two risk factors act synergistically. Subsequent cohort studies in Taiwan confirm these results. IARC classified aflatoxin as a Group 1 human carcinogen in 1993, based on sufficient evidence in humans and experimental

  8. The in vitro effect of selected essential oils on the growth and mycotoxin production of Aspergillus species.

    PubMed

    Císarová, Miroslava; Tančinová, Dana; Medo, Juraj; Kačániová, Miroslava

    2016-10-02

    The aim of the present study was to assess the antifungal and anti-toxinogenic activity of 15 essential oils (EOs) against three fungi of the genus Aspergillus (A. parasiticus KMi-227-LR, A. parasiticus KMi-220-LR and A. flavus KMi-202-LR). The minimum inhibitory doses (MIDs) of the tested essential oils and their antifungal activity were determined using the micro-atmosphere method. The original commercial essential oil samples of Jasminum officinale L., Thymus vulgaris L., Syzygium aromaticum (L.) Merrill & Perry, Rosmarinus officinalis L., Ocimum basilicum L., Eucalyptus globulus Labill., Salvia officinalis L., Citrus limon (L.) Burm, Origanum vulgare L., Lavandula angustifolia Mill., Carum carvi L., Citrus sinensis (L.) Osbeck., Zingiber officinalis Rosc., Mentha piperita L. and Cinnamomum zeylanicum Nees. (C. verum J.S.Presl.) were produced in Slovakia (Calendula a.s., Nová Ľubovňa, Slovakia). All essential oils exhibited activity against all tested strains of fungi. After 14 days of incubation, A. flavus (KMi-202-LR) showed the highest susceptibility with a growth inhibition percentage (GIP) of 18.70% to C. limon and 5.92% to C. sinensis, while A. parasiticus (KMi-220-LR) exhibited a GIP of 20.56% to J. officinale. The minimum inhibitory doses (MIDs) of EOs with the most significant activity were recorded. The best antifungal activity, using the micro-atmosphere method was found in S. aromaticum with an MID of 62.5 μL L(-1) air, T. vulgaris (MID of 62.5 μL L(-1) air) and O. vulgare (MID of 31.5 μL L(-1) air) against all tested strains. Mycotoxin production of the tested strains was evaluated by the thin layer chromatography (TLC) method. Mycotoxin production of AFB1 and AFG1 was inhibited following all treatments with C. carvi, R. officinale and S. officinale, Eucalyptus globulus L. and O. basilicum L. Essential oils exhibited a potential inhibition activity against toxic fungi, although, these affected only the production of AFB1.

  9. Biotransformation of aflatoxin B1 and aflatoxin G1 in peanut meal by anaerobic solid fermentation of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.

    PubMed

    Chen, Yujie; Kong, Qing; Chi, Chen; Shan, Shihua; Guan, Bin

    2015-10-15

    The purpose of this study was to explore the ability of anaerobic solid fermentation of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus to biotransform aflatoxins in peanut meal. The pH of the peanut meal was adjusted above 10, and then heated for 10 min at 100 °C, 115 °C and 121 °C. The S. thermophilus and L. delbrueckii subsp. bulgaricus were precultured together in MRS broth for 48 h at 37 °C. The heated peanut meal was mixed with precultured MRS broth containing 7.0×10(8) CFU/mL of S. thermophilus and 3.0×10(3) CFU/mL of L. delbrueckii subsp. bulgaricus with the ratio of 1 to 1 (weight to volume) and incubated in anaerobic jars at 37 °C for 3 days. The aflatoxin content in the peanut meal samples was determined by HPLC. The results showed that the peanut meal contained mainly aflatoxin B1 (AFB1) (10.5±0.64 μg/kg) and aflatoxin G1 (AFG1) (18.7±0.55 μg/kg). When heat treatment was combined with anaerobic solid fermentation, the biotransformation rate of aflatoxins in peanut meal could attain 100%. The cytotoxicity of fermented peanut meal to L929 mouse connective tissue fibroblast cells was determined by MTT assay and no significant toxicity was observed in the fermented peanut meal. Furthermore, heat treatment and anaerobic solid fermentation did not change the amino acid concentrations and profile in peanut meal.

  10. Antifungal properties and inhibitory effects upon aflatoxin production of Thymus vulgaris L. by Aspergillus flavus Link.

    PubMed

    Kohiyama, Cássia Yumie; Yamamoto Ribeiro, Milene Mayumi; Mossini, Simone Aparecida Galerani; Bando, Erika; Bomfim, Natália da Silva; Nerilo, Samuel Botião; Rocha, Gustavo Henrique Oliveira; Grespan, Renata; Mikcha, Jane Martha Graton; Machinski, Miguel

    2015-04-15

    The antifungal and antiaflatoxigenic properties of Thymus vulgaris essential oil (TEO) were evaluated upon Aspergillus flavus "in vitro". Suspension containing 10(6) of A. flavus were cultivated with TEO in concentrations ranging from 50 to 500 μg/mL. TEO reached minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) at 250 μg/mL. Inhibition of ergosterol biosynthesis was detected at a concentration of 100 μg/mL of TEO. Morphological evaluation performed by both light microscopy and scanning electron microscopy showed that antifungal activity of TEO could be detected starting at a concentration of 50 μg/mL and the fungicide effect at a concentration of 250 μg/mL. TEO completely inhibited production of both B1 and B2 aflatoxins (AFB1 and AFB2) at a concentration of 150 μg/mL. This way, fungal biomass development and aflatoxin production were dependent on TEO concentration. Therefore, TEO was capable of controlling the growth of A. flavus and its production of aflatoxins.

  11. Presence of mycotoxins in sorghum and intake estimation in Tunisia.

    PubMed

    Oueslati, Souheib; Blesa, Jesús; Moltó, Juan Carlos; Ghorbel, Abdelwahed; Mañes, Jordi

    2014-01-01

    Sorghum samples (n = 60) from Tunisian markets were analysed for the occurrence of 22 of both traditional and emerging mycotoxins. Samples were extracted with a QuEChERS-like method and mycotoxins were detected by LC-MS/MS. This method was validated and adequate analytical parameters were obtained. All samples had contamination with mycotoxins and several samples had higher contamination levels than European Union legislative limits (MLs). The most frequently found mycotoxins were ENB (100%), OTA (98%), ENA₁ (63%), ENB₁ (56%), BEA (48%), AFB1 (38%) and STG (33%). Mean contaminations were 30.7, 1.93, 33.2, 51.0, 15.4, 1.49 and 20.5 µg kg(-1), respectively. While two samples were contaminated with FB2 and FB3 at mean values of 16.2 and 45.9 µg kg(-1), respectively, one sample was contaminated with AFB2 and ZEA at levels of 0.82 and 45.0 µg kg(-1), respectively. The results were used to estimate the daily intake of mycotoxins through sorghum consumption with regard to normal consumers (low-risk population) and high consumers such as babies (high-risk consumers) who are facing an alarming situation.

  12. Biosorption of B-aflatoxins Using Biomasses Obtained from Formosa Firethorn [Pyracantha koidzumii (Hayata) Rehder

    PubMed Central

    Ramales-Valderrama, Rosa Adriana; Vázquez-Durán, Alma; Méndez-Albores, Abraham

    2016-01-01

    Mycotoxin adsorption onto biomaterials is considered as a promising alternative for decontamination without harmful chemicals. In this research, the adsorption of B-aflatoxins (AFB1 and AFB2) using Pyracantha koidzumii biomasses (leaves, berries and the mixture of leaves/berries) from aqueous solutions was explored. The biosorbent was used at 0.5% (w/v) in samples spiked with 100 ng/mL of B-aflatoxin standards and incubated at 40 °C for up to 24 h. A standard biosorption methodology was employed and aflatoxins were quantified by an immunoaffinity column and UPLC methodologies. The biosorbent-aflatoxin interaction mechanism was investigated from a combination of zeta potential (ζ), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The highest aflatoxin uptakes were 86% and 82% at 6 h using leaves and the mixture of leaves/berries biomasses, respectively. A moderate biosorption of 46% was attained when using berries biomass. From kinetic studies, the biosorption process is described using the first order adsorption model. Evidence from FTIR spectra suggests the participation of hydroxyl, amine, carboxyl, amide, phosphate and ketone groups in the biosorption and the mechanism was proposed to be dominated by the electrostatic interaction between the negatively charged functional groups and the positively charged aflatoxin molecules. Biosorption by P. koidzumii biomasses has been demonstrated to be an alternative to conventional systems for B-aflatoxins removal. PMID:27420096

  13. Preparation for aflatoxin B(1)-cationized bovine serum albumin based on Mannich-type reaction.

    PubMed

    Zhou, Youxiang; Wu, Jiajia; Yu, Wei; Xu, Ying; Wang, Ping; Xie, Bijun; Chen, Fusheng

    2007-12-01

    Aflatoxin B(1) (AFB(1)), which is commonly found in agricultural commodities, is one of the most potent carcinogenic mycotoxins. To ensure food safety, rapid and low-cost immunological methods have been applied to detect AFB(1) worldwide. A key step in these immunological methods is coupling AFB(1) to carrier proteins; AFB(1) is usually deviated to AFB(1)-oxime and coupled to carrier proteins to form the AFB(1)-oxime-protein conjugate. In the current research, AFB(1) was directly coupled with cationized bovine serum albumin (cBSA) using a method based on Mannich-type principles. The coupling effects were investigated with different initial molar ratios of AFB(1) to cBSA. The conjugate molar ratio was 6.4:1 when the initial molar ratio was 40:1. The cationized proteins and their conjugates were identified by UV-Vis and FT-IR spectra, which showed the characteristic bands of the ethylendiamine group and AFB(1), respectively. After BALB/c mice were immunized with AFB(1)-cBSA, a quicker immunological response and a similar sensitivity of antisera against AFB(1) were observed, compared with immunization by AFB(1)-oxime-BSA. This suggests that the Mannich-type reaction might be an alternative method of preparation for AFB(1)-protein.

  14. Ameliorative Effects of Neutral Electrolyzed Water on Growth Performance, Biochemical Constituents, and Histopathological Changes in Turkey Poults during Aflatoxicosis

    PubMed Central

    Gómez-Espinosa, Denise; Cervantes-Aguilar, Francisco Javier; Del Río-García, Juan Carlos; Villarreal-Barajas, Tania; Vázquez-Durán, Alma; Méndez-Albores, Abraham

    2017-01-01

    Different in vitro and in silico approaches from our research group have demonstrated that neutral electrolyzed water (NEW) can be used to detoxify aflatoxins. The objective of this investigation was to evaluate the ability of NEW to detoxify B-aflatoxins (AFB1 and AFB2) in contaminated maize and to confirm detoxification in an in vivo experimental model. Batches of aflatoxin-contaminated maize were detoxified with NEW and mixed in commercial feed. A total of 240 6-day-old female large white Nicholas-700 turkey poults were randomly divided into four treatments of six replicates each (10 turkeys per replicate), which were fed ad libitum for two weeks with the following dietary treatments: (1) control feed containing aflatoxin-free maize (CONTROL); (2) feed containing the aflatoxin-contaminated maize (AF); (3) feed containing the aflatoxin-contaminated maize detoxified with NEW (AF + NEW); and (4) control feed containing aflatoxin-free maize treated with NEW (NEW). Compared to the control groups, turkey poults of the AF group significantly reduced body weight gain and increased feed conversion ratio and mortality rate; whereas turkey poults of the AF + NEW group did not present significant differences on productive parameters. In addition, alterations in serum biochemical constituents, enzyme activities, relative organ weight, gross morphological changes and histopathological studies were significantly mitigated by the aflatoxin-detoxification procedure. From these results, it is concluded that the treatment of aflatoxin-contaminated maize with NEW provided reasonable protection against the effects caused by aflatoxins in young turkey poults. PMID:28335412

  15. Fabrication of a novel nanocomposite based on sol-gel process for hollow fiber-solid phase microextraction of aflatoxins: B1 and B2, in cereals combined with high performane liquid chromatography-diode array detection.

    PubMed

    Es'haghi, Zarrin; Sorayaei, Hoda; Samadi, Fateme; Masrournia, Mahboubeh; Bakherad, Zohreh

    2011-10-15

    The new pre-concentration technique, hollow fiber-solid phase microextraction based on carbon nanotube reinforced sol-gel and liquid chromatography-photodiode array detection was applied to determination of aflatoxins B(1), B(2) (AFB(1), AFB(2)) in rice, peanut and wheat samples. This research provides an overview of trends related to synthesis of solid phase microextraction (SPME) sorbnents that improves the assay of aflatoxins as the semi-polar compounds in several real samples. It mainly includes summary and a list of the results for a simple carbon nanotube reinforced sol-gel in-fiber device. This device was used for extraction, pre-concentration and determination of aflatoxins B1, B2 in real samples. In this technique carbon nanotube reinforced sol was prepared by the sol-gel method via the reaction of phenyl trimethoxysilane (PTMS) with a basic catalyst (tris hydroxymethyl aminomethan). The influences of microextraction parameters such as pH, ageing time, carbon nanotube contents, desorption conditions, desorption solvent and agitation speed were investigated. Optimal HPLC conditions were: C(18) reversed phase column for separation, water-acetonitril-methanol (35:10:55) as the mobile phase and maximum wavelength for detection was 370 nm. The method was evaluated statistically and under optimized conditions, the detection limits for the analytes were 0.074 and 0.061 ng/mL for B1 and B2 respectively. Limit of quantification for B1 and B2 was 0.1 ng/mL too (n=7). The precisions were in the range of 2.829-2.976% (n=3), and linear ranges were within 0.1 and 400 ng/mL. The method was successfully applied to the analysis of cereals (peanut, wheat, rice) with the relative recoveries from 47.43% to 106.83%.

  16. Nitrate-responsive miR393/AFB3 regulatory module controls root system architecture in Arabidopsis thaliana.

    PubMed

    Vidal, Elena A; Araus, Viviana; Lu, Cheng; Parry, Geraint; Green, Pamela J; Coruzzi, Gloria M; Gutiérrez, Rodrigo A

    2010-03-02

    One of the most striking examples of plant developmental plasticity to changing environmental conditions is the modulation of root system architecture (RSA) in response to nitrate supply. Despite the fundamental and applied significance of understanding this process, the molecular mechanisms behind nitrate-regulated changes in developmental programs are still largely unknown. Small RNAs (sRNAs) have emerged as master regulators of gene expression in plants and other organisms. To evaluate the role of sRNAs in the nitrate response, we sequenced sRNAs from control and nitrate-treated Arabidopsis seedlings using the 454 sequencing technology. miR393 was induced by nitrate in these experiments. miR393 targets transcripts that code for a basic helix-loop-helix (bHLH) transcription factor and for the auxin receptors TIR1, AFB1, AFB2, and AFB3. However, only AFB3 was regulated by nitrate in roots under our experimental conditions. Analysis of the expression of this miR393/AFB3 module, revealed an incoherent feed-forward mechanism that is induced by nitrate and repressed by N metabolites generated by nitrate reduction and assimilation. To understand the functional role of this N-regulatory module for plant development, we analyzed the RSA response to nitrate in AFB3 insertional mutant plants and in miR393 overexpressors. RSA analysis in these plants revealed that both primary and lateral root growth responses to nitrate were altered. Interestingly, regulation of RSA by nitrate was specifically mediated by AFB3, indicating that miR393/AFB3 is a unique N-responsive module that controls root system architecture in response to external and internal N availability in Arabidopsis.

  17. Portable visual quantitative detection of aflatoxin B1 using a target-responsive hydrogel and a distance-readout microfluidic chip.

    PubMed

    Ma, Yanli; Mao, Yu; Huang, Di; He, Zhe; Yan, Jinmao; Tian, Tian; Shi, Yuanzhi; Song, Yanling; Li, Xingrui; Zhu, Zhi; Zhou, Leiji; Yang, Chaoyong James

    2016-08-02

    Aflatoxin B1 (AFB1), as the secondary metabolite of molds, is the most predominant and toxic mycotoxin that seriously threatens the health of humans and animals. In this work, an AFB1-responsive hydrogel was synthesized for highly sensitive and portable detection of AFB1. The AFB1-responsive hydrogel was prepared using an AFB1 aptamer and its two short complementary DNA strands as cross-linkers. For visual detection of AFB1, the hydrogel is preloaded with gold nanoparticles (AuNPs). Upon introduction of AFB1, the AFB1 aptamer binds with AFB1, leading to the disruption of the hydrogel and release of the AuNPs with a distinct color change of the supernatant from colorless to red. In order to lower the detection limit and extend the method to quantitative analysis, a distance-readout volumetric bar chart chip (V-chip) was combined with an AFB1-responsive hydrogel preloaded with platinum nanoparticles (PtNPs). In the presence of AFB1, the hydrogel collapses and releases PtNPs which can catalyze the decomposition of H2O2 to generate O2. The increasing gas pressure moves a red ink bar in the V-chip and provides a quantitative relationship between the distance and the concentration of AFB1. The method was applied for detection of AFB1 in beer, with a detection limit of 1.77 nM (0.55 ppb) where an immunoaffinity column (IAC) of AFB1 was used to cleanup and pre-concentrate the sample, which satisfies the testing requirement of 2.0 ppb set by the European Union. The combination of an AFB1-responsive hydrogel with a distance-based readout V-chip offers a user-friendly POCT device, which has great potential for rapid, portable, selective, and quantitative detection of AFB1 in real samples to ensure food safety and avoid subsequent economic losses.

  18. Human health implications from co-exposure to aflatoxins and fumonisins in maize-based foods in Latin America: Guatemala as a case study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Co-occurence of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in maize has been demonstrated in many surveys. Combined-exposure to FB1 and AFB1 was of concern to the Joint FAO/WHO Expert Committee on Food Additives because of the known genotoxicity of AFB1 and the ability of FB1 to induce regenerative...

  19. Low cost quantitative digital imaging as an alternative to qualitative in vivo bioassays for analysis of active aflatoxin B1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxin B1 (AFB1) producing fungi contaminate food and feed and are a major health concern. To minimize the sources and incidence of AFB1 illness there is a need to develop affordable, sensitive mobile devices for detection of active AFB1. In the present study we used a low cost fluorescence detec...

  20. Suppression of aflatoxin B1-induced lipid abnormalities and macromolecule-adduct formation by L-carnitine.

    PubMed

    Sachan, D S; Yatim, A M

    1992-01-01

    The fatty liver and hypolipidemia caused by aflatoxin B1 (AFB1) were studied in male Sprague-Dawley rats fed Purina Rat Chow with or without L-carnitine supplement for 6 weeks. In Experiment 1, the rats (n = 20) were divided into four groups, i.e., nonsupplemented control (NSC), nonsupplemented AFB1 (NSA), carnitine supplemented control (CSC), and carnitine supplemented AFB1 (CSA). The NSA and CSA groups were given an oral dose of [3H]AFB1 (1 mg/kg) 6 hr before kill. In Experiment 2 (n = 10) there were only NSA and CSA groups and they were killed 24 hr post-AFB1 administration. Hepatic and plasma concentrations of total lipid, triglycerides, AFB1-macromolecules adducts and urinary excretion of AFB1 were determined. Carnitine supplementation ameliorated AFB1-induced hepatic steatosis and hypolipidemia. Supplementary carnitine reduced covalent binding of AFB1 to hepatic DNA, RNA, and protein. The carnitine effect was more pronounced after 24 hr than after 6 hr of AFB1 treatment. We conclude that supplementary carnitine suppressed AFB1-induced fatty liver and AFB1-macromolecule adduct formation in the rat.

  1. Metabolism of aflatoxins: key enzymes and interindividual as well as interspecies differences.

    PubMed

    Dohnal, Vlastimil; Wu, Qinghua; Kuča, Kamil

    2014-09-01

    Aflatoxins are potent hepatocarcinogen in animal models and suspected carcinogen in humans. The most important aflatoxin in terms of toxic potency and occurrence is aflatoxin B1 (AFB1). In this review, we mainly summarized the key metabolizing enzymes of AFB1 in animals and humans. Moreover, the interindividual and the interspecies differences in AFB1 metabolism are highly concerned. In human liver, CYP3A4 plays an important role in biotransforming AFB1 to the toxic product AFB1-8,9-epoxide. In human lung, CYP2A13 has a significant activity in metabolizing AFB1 to AFB1-8,9-epoxide and AFM1-8,9-epoxide. The epoxide of AFB1-8,9-epoxide could conjugate with glutathione to reduce the toxicity by glutathione-S-transferase (GST). In poultry species, CYP2A6, CYP3A37, CYP1A5, and CYP1A1 are responsible for bioactivation of AFB1. There are interindividual variations in the rate of activation of aflatoxins in various species, and there are also differences between children and adults. The age and living regions are important factors affecting resistance of species to AFB1. The rate of AFB1-8,9-epoxide formation and its conjugation with glutathione are key parameters in interspecies and interindividual differences in sensitivity to the toxic effect of AFB1. This review provides an important information for key metabolizing enzymes and the global metabolism of aflatoxins in different species.

  2. The effect of aflatoxin-B1 on red drum (Sciaenops ocellatus) and assessment of dietary supplementation of NovaSil for the prevention of aflatoxicosis.

    PubMed

    Zychowski, Katherine E; Hoffmann, Aline Rodrigues; Ly, Hoai J; Pohlenz, Camilo; Buentello, Alejandro; Romoser, Amelia; Gatlin, Delbert M; Phillips, Timothy D

    2013-09-16

    Aflatoxin B1 (AFB1) is a potent carcinogen that causes growth stunting, immunosuppression and liver cancer in multiple species. The recent trend of replacing fishmeal with plant-based proteins in fish feed has amplified the AFB1 exposure risk in farm-raised fish. NovaSil (NS), a calcium montmorillonite clay, has previously been shown to reduce AFB1 bioavailability safely and efficaciously in several mammalian species. This study was designed to: (1) evaluate AFB1 impact on cultured red drum, Sciaenops ocellatus, over the course of seven weeks; and (2) assess NS supplementation as a strategy to prevent aflatoxicosis. Fish were fed diets containing 0, 0.1, 0.25, 0.5, 1, 2, 3, or 5 ppm AFB1. Two additional treatment groups were fed either 5 ppm AFB1 + 1% NS or 5 ppm AFB1 + 2% NS. Aflatoxin B1 negatively impacted red drum weight gain, survival, feed efficiency, serum lysozyme concentration, hepatosomatic index (HSI), whole-body lipid levels, liver histopathological scoring, as well as trypsin inhibition. NovaSil inclusion in AFB1-contaminated diets improved weight gain, feed efficiency, serum lysozyme concentration, muscle somatic index, and intraperitoneal fat ratios compared to AFB1-treated fish. Although not significant, NS reduced AFB1-induced histopathological changes in the liver and decreased Proliferating Cell Nuclear Antigen (PCNA) staining. Importantly, NS supplementation improved overall health of AFB1-exposed red drum.

  3. Aflatoxin B1 Induces Reactive Oxygen Species-Mediated Autophagy and Extracellular Trap Formation in Macrophages

    PubMed Central

    An, Yanan; Shi, Xiaochen; Tang, Xudong; Wang, Yang; Shen, Fengge; Zhang, Qiaoli; Wang, Chao; Jiang, Mingguo; Liu, Mingyuan; Yu, Lu

    2017-01-01

    Aflatoxins are a group of highly toxic mycotoxins with high carcinogenicity that are commonly found in foods. Aflatoxin B1 (AFB1) is the most toxic member of the aflatoxin family. A recent study reported that AFB1 can induce autophagy, but whether AFB1 can induce extracellular traps (ETs) and the relationships among innate immune responses, reactive oxygen species (ROS), and autophagy and the ETs induced by AFB1 remain unknown. Here, we demonstrated that AFB1 induced a complete autophagic process in macrophages (MΦ) (THP-1 cells and RAW264.7 cells). In addition, AFB1 induced the generation of MΦ ETs (METs) in a dose-dependent manner. In particular, the formation of METs significantly reduced the AFB1 content. Further analysis using specific inhibitors showed that the inhibition of either autophagy or ROS prevented MET formation caused by AFB1, indicating that autophagy and ROS were required for AFB1-induced MET formation. The inhibition of ROS prevented autophagy, indicating that ROS generation occurred upstream of AFB1-induced autophagy. Taken together, these data suggest that AFB1 induces ROS-mediated autophagy and ETs formation and an M1 phenotype in MΦ. PMID:28280716

  4. Effective degradation of aflatoxin B1 using a novel thermophilic microbial consortium TADC7.

    PubMed

    Wang, Yi; Zhao, Chunxia; Zhang, Dongdong; Zhao, Mingming; Zheng, Dan; Lyu, Yucai; Cheng, Wei; Guo, Peng; Cui, Zongjun

    2017-01-01

    We constructed a novel thermophilic microbial consortium, TADC7, with stable and efficient aflatoxin B1 (AFB1) degradation activity. The microbial consortium degraded more than 95% of the toxin within 72h when cultured with AFB1, and the optimum temperature was 55-60°C. TADC7 tolerated high doses of AFB1, with no inhibitory effects up to 5000μgL(-1) AFB1; moreover, the degradation kinetics fit well with the Monod model. The proteins or enzymes in the TADC7 cell-free supernatant played a major role in AFB1 degradation. AFB1 degradation by the cell-free supernatant was stable up to 90°C, with an optimal pH of 8-10. We performed 16S rRNA sequencing to determine TADC7 community structure dynamics; the results indicated that Geobacillus and Tepidimicrobium played major roles in AFB1 degradation.

  5. Caffeic acid phenethyl ester modulates aflatoxin B1-induced hepatotoxicity in rats.

    PubMed

    Akçam, Mustafa; Artan, Reha; Yilmaz, Aygen; Ozdem, Sebahat; Gelen, Tekinalp; Nazıroğlu, Mustafa

    2013-12-01

    Aflatoxin B1 (AFB1) is the most potent of the mycotoxins and is widely observed in nutrition abnormalities. There are some studies suggesting oxidative stress-induced toxic changes on liver related to AFB1 toxicity. The aim of the present study was to evaluate whether antioxidant caffeic acid phenethyl ester (CAPE) relieves oxidative stress in AFB1-induced liver injury in rat. Twenty-four male rats were equally divided into three groups. The first group was used as a control. The second group received three doses of AFB1. The three doses of CAPE were given to constitute the third group with doses of AFB1. After 10 days of experiment, liver and serum samples were taken from all animals. Serum gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), glutathione s-transferase (GST), nitric oxide (NO) and sulfhydryl values were higher in the AFB1 group than in control, whereas serum GGT, ALP, GST and NO values were decreased by in the AFB1 + CAPE group than in AFB1 group. Liver GST, total oxidant capacity, sulfhydryl, apoptosis index and ischemia-modified albumin values were higher in the AFB1 group than in control, whereas the GST activity and apoptosis index were lower in the AFB1 + CAPE group than in the AFB1 group. There were histopathological degeneration and apoptosis in hepatocytes of AFB1 group. The findings were totally recovered by CAPE administration. In conclusion, we observed that AFB1 caused oxidative and nitrosative hepatoxicity to hepatocytes in the rat. However, CAPE induced protective effects on the AFB1-induced hepatoxicity by modulating free radical production, biochemical values and histopathological alterations.

  6. Protective roles of sodium selenite against aflatoxin B1-induced apoptosis of jejunum in broilers.

    PubMed

    Peng, Xi; Zhang, Shengqiang; Fang, Jing; Cui, Hengmin; Zuo, Zhicai; Deng, Junliang

    2014-12-01

    The effects of aflatoxin B1 (AFB1) exposure and sodium selenite supplementation on cell apoptosis of jejunum in broilers were studied. A total of 240 one-day-old male AA broilers were randomly assigned four dietary treatments containing 0 mg/kg of AFB1 (control), 0.3 mg/kg AFB1 (AFB1), 0.4 mg/kg supplement Se (+ Se) and 0.3 mg/kg AFB1 + 0.4 mg/kg supplement Se (AFB1 + Se), respectively. Compared with the control broilers, the number of apoptotic cells, the expression of Bax and Caspase-3 mRNA were significantly increased, while the expression of Bcl-2 mRNA and the Bcl-2/Bax ratio were significantly decreased in AFB1 broilers. The number of apoptotic cells and the expression of Caspase-3 mRNA in AFB1 + Se broilers were significantly higher than those in the control broilers, but significantly lower than those in AFB1 broilers. There were no significant changes in the expression of Bax mRNA between AFB1 + Se and control broilers; the expression of Bcl-2 mRNA and the Bcl-2/Bax ratio in AFB1 + Se broilers were significantly lower than those in the control broilers, but significantly higher than those in AFB1 broilers. In conclusion, 0.3 mg/kg AFB1 in the diet can increase cell apoptosis, decrease Bcl-2 mRNA expression, and increase of Bax and Caspase-3 mRNA expression in broiler's jejunum. However, supplementation of dietary sodium selenite at the concentration of 0.4 mg/kg Se may ameliorate AFB1-induced apoptosis by increasing Bcl-2 mRNA expression, and decreasing Bax and Caspase-3 mRNA expression.

  7. Low cost quantitative digital imaging as an alternative to qualitative in vivo bioassays for analysis of active aflatoxin B1.

    PubMed

    Rasooly, Reuven; Do, Paula M; Hernlem, Bradley J

    2016-06-15

    Aflatoxin B1 (AFB1) producing fungi contaminate food and feed and are a major health concern. To minimize the sources and incidence of AFB1 illness there is a need to develop affordable, sensitive mobile devices for detection of active AFB1. In the present study we used a low cost fluorescence detector and describe two quantitative assays for detection of detoxified and active AFB1 demonstrating that AFB1 concentration can be measured as intensity of fluorescence. When the assay plate containing increasing concentrations of AFB1 is illuminated with a 366 nm ultraviolet lamp, AFB1 molecules absorb photons and emit blue light with peak wavelength of 432 nm. The fluorescence intensity increased in dose dependent manner. However, this method cannot distinguish between active AFB1 which poses a threat to health, and the detoxified AFB1 which exhibits no toxicity. To measure the toxin activity, we used a cell based assay that makes quantification more robust and is capable of detecting multiple samples simultaneously. It is an alternative to the qualitative duckling bioassay which is the "gold-standard" assay currently being used for quantitative analysis of active AFB1. AFB1 was incubated with transduced Vero cells expressing the green fluorescence protein (GFP) gene. After excitation with blue light at 475 nm, cells emitted green light with emission peak at 509 nm. The result shows that AFB1 inhibits protein expression in a concentration dependent manner resulting in proportionately less GFP fluorescence in cells exposed to AFB1. The result also indicates strong positive linear relationship with R(2)=0.90 between the low cost CCD camera and a fluorometer, which costs 100 times more than a CCD camera. This new analytical method for measuring active AFB1 is low in cost and combined with in vitro assay, is quantitative. It also does not require the use of animals and may be useful especially for laboratories in regions with limited resources.

  8. Determination of Aflatoxin B1-Lysine in Pig Serum and Plasma by Liquid Chromatography-Tandem Mass Spectrometry.

    PubMed

    Di Gregorio, Mayra C; Jager, Alessandra V; Costa, Aline A; Bordin, Keliani; Rottinhghaus, George E; Petta, Tânia; Souto, Pollyana C M C; Budiño, Fabio E L; Oliveira, Carlos A F

    2017-04-01

    Aflatoxin B1 (AFB1) is a hepatocarcinogen produced by certain Aspergillus species growing on crops. After biotransformation in the liver, AFB1 generates several metabolites, one of which is AFB1 bound to lysine on serum albumin. AFB1-lysine (AFB1-lys) is a digest product of AFB1-albumin and is considered a biomarker of exposure to AFB1 in humans and animals. The objectives of this paper were to evaluate the performance characteristics of a new analytical method for determination of AFB1-lys levels in pig serum, heparinized and ethylenediaminetetraacetic acid (EDTA) plasma and to evaluate the interference of these anticoagulants in AFB1-lys quantification. Blank blood samples were obtained from eight crossbreed 91-day-old barrows fed AFB1-free diets. Pooled samples (n = 3) and individual samples of serum, EDTA and heparinized plasma collected from five pigs were enzymatically digested with pronase at 37°C for 4 h. AFB1-lys was isolated by solid-phase extraction and quantified by liquid chromatography coupled to tandem mass spectrometry. The analytical method was applied for determination of AFB1-lys in serum and EDTA plasma collected from five 49-day-old crossbreed barrows fed ad libitum diets containing 1.1 mg of AFB1 per kg of feed during 7 days (three animals) or 42 days (two animals). Samples of heparinized plasma were only available from animals intoxicated for 42 days. All animals had lower levels of AFB1-lys in EDTA plasma samples (24.78-37.40 ng/mL), when compared to serum (49.32-252.07 ng/mL-1) or heparinized plasma (176.81 and 264.24 ng/mL-1). EDTA did not interfere in AFB1-lys standard detection, but our findings suggest that EDTA should be avoided during blood collection since it affects the pronase activity in AFB1-albumin adduct digestion and, consequently, causes a reduction in the AFB1-lys levels. Hence, determination of AFB1-lys in serum and heparinized plasma is an approach to assess an individual's exposure of swine to AFB1.

  9. Occupational Exposure to Aflatoxin B1 in a Portuguese Poultry Slaughterhouse.

    PubMed

    Viegas, Susana; Veiga, Luísa; Almeida, Ana; dos Santos, Mateus; Carolino, Elisabete; Viegas, Carla

    2016-03-01

    Aflatoxin B1 (AFB1) is a secondary metabolite produced by the fungi Aspergillus flavus and is the most potent hepatocarcinogen known in mammals and has been classified by the International Agency of Research on Cancer as Group 1 carcinogen. Although dietary exposure to AFB1 has been extensively documented, there are still few studies dedicated to the problem of occupational exposure. Considering recent findings regarding AFB1 occupational exposure in poultry production, it was considered relevant to clarify if there is also exposure in poultry slaughterhouses. Occupational exposure assessment to AFB1 was done with a biomarker of internal dose that measures AFB1 in the serum by enzyme-linked immunosorbent assay. Thirty workers from a slaughterhouse were enrolled in this study. A control group (n = 30) was also considered in order to know AFB1 background levels for Portuguese population. Fourteen workers (47.0%) showed detectable levels of AFB1 with values from 1.06 to 4.03ng ml(-1), with a mean value of 1.73ng ml(-1). No AFB1 was detected in serum of individuals used as controls. Despite uncertainties regarding the exposure route that is contributing more to exposure (inhalation or dermal) is possible to state that exposure to AFB1 is occurring in the slaughterhouse studied. It seems that reducing AFB1 contamination in poultry production can have a positive result in this occupational setting.

  10. Bioactivation and Regioselectivity of Pig Cytochrome P450 3A29 towards Aflatoxin B1

    PubMed Central

    Wu, Jun; Chen, Ruohong; Zhang, Caihui; Li, Kangbai; Xu, Weiying; Wang, Lijuan; Chen, Qingmei; Mu, Peiqiang; Jiang, Jun; Wen, Jikai; Deng, Yiqun

    2016-01-01

    Due to unavoidable contaminations in feedstuff, pigs are easily exposed to aflatoxin B1 (AFB1) and suffer from poisoning, thus the poisoned products potentially affect human health. Heretofore, the metabolic process of AFB1 in pigs remains to be clarified, especially the principal cytochrome P450 oxidases responsible for its activation. In this study, we cloned CYP3A29 from pig liver and expressed it in Escherichia coli, and its activity has been confirmed with the typical P450 CO-reduced spectral characteristic and nifedipine-oxidizing activity. The reconstituted membrane incubation proved that the recombinant CYP3A29 was able to oxidize AFB1 to form AFB1-exo-8,9-epoxide in vitro. The structural basis for the regioselective epoxidation of AFB1 by CYP3A29 was further addressed. The T309A mutation significantly decreased the production of AFBO, whereas F304A exhibited an enhanced activation towards AFB1. In agreement with the mutagenesis study, the molecular docking simulation suggested that Thr309 played a significant role in stabilization of AFB1 binding in the active center through a hydrogen bond. In addition, the bulk phenyl group of Phe304 potentially imposed steric hindrance on the binding of AFB1. Our study demonstrates the bioactivation of pig CYP3A29 towards AFB1 in vitro, and provides the insight for understanding regioselectivity of CYP3A29 to AFB1. PMID:27626447

  11. Aflatoxin B1 invokes apoptosis via death receptor pathway in hepatocytes.

    PubMed

    Mughal, Muhammad Jameel; Xi, Peng; Yi, Zhou; Jing, Fang

    2017-01-31

    The fungal metabolites produced by Aspergillus flavus and Aspergillus parasiticus cause detrimental health effects on humans and animals. Particularly aflatoxin B1 (AFB1) is the most studied and a well-known global carcinogen, producing hepatotoxic, genotoxic and immunotoxic effects in multiple species. AFB1 is shown to provoke liver dysfunctioning by causing hepatocytes apoptosis and disturbing cellular enzymatic activities. In liver, AFB1 causes apoptosis via extrinsic mechanism because of high expression of death receptor pathway. The detailed mechanism of AFB1 induced hepatocytes apoptosis, via death receptor pathway still remains elusive. So the present study was conducted to explore apoptotic mechanism initiated by death receptors and associated genes in aflatoxin B1 induced liver apoptosis in chickens fed with AFB1 for 3 weeks. Results from the present study displayed histopathological and ultrastructural changes in liver such as hydropic degeneration, fatty vacuolar degeneration and proliferation of bile duct in hepatocytes in AFB1 group, along with imbalance between reactive oxygen species (ROS) and antioxidant defense system upon AFB1 ingestion. Moreover, AFB1 intoxicated chickens showed upregulation of death receptors FAS, TNFR1 and associated genes and downregulation of inhibitory apoptotic proteins XIAP and BCL-2. The results obtained from this novel and comprehensive study including histopathological, ultrastructural, flow cytometrical and death receptor pathway gene expression profiles, will facilitate better understanding of mechanisms and involvement of death receptor pathway in hepatocytes apoptosis induced by AFB1 and ultimately may be helpful in bringing down the toxigenic potential of AFB1.

  12. Complete protection against aflatoxin B(1)-induced liver cancer with a triterpenoid: DNA adduct dosimetry, molecular signature, and genotoxicity threshold.

    PubMed

    Johnson, Natalie M; Egner, Patricia A; Baxter, Victoria K; Sporn, Michael B; Wible, Ryan S; Sutter, Thomas R; Groopman, John D; Kensler, Thomas W; Roebuck, Bill D

    2014-07-01

    In experimental animals and humans, aflatoxin B1 (AFB1) is a potent hepatic toxin and carcinogen. The synthetic oleanane triterpenoid 1-[2-cyano-3-,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im), a powerful activator of Keap1-Nrf2 signaling, protects against AFB1-induced toxicity and preneoplastic lesion formation (GST-P-positive foci). This study assessed and mechanistically characterized the chemoprotective efficacy of CDDO-Im against AFB1-induced hepatocellular carcinoma (HCC). A lifetime cancer bioassay was undertaken in F344 rats dosed with AFB1 (200 μg/kg rat/day) for four weeks and receiving either vehicle or CDDO-Im (three times weekly), one week before and throughout the exposure period. Weekly, 24-hour urine samples were collected for analysis of AFB1 metabolites. In a subset of rats, livers were analyzed for GST-P foci. The comparative response of a toxicogenomic RNA expression signature for AFB1 was examined. CDDO-Im completely protected (0/20) against AFB1-induced liver cancer compared with a 96% incidence (22/23) observed in the AFB1 group. With CDDO-Im treatment, integrated level of urinary AFB1-N(7)-guanine was significantly reduced (66%) and aflatoxin-N-acetylcysteine, a detoxication product, was consistently elevated (300%) after the first AFB1 dose. In AFB1-treated rats, the hepatic burden of GST-P-positive foci increased substantially (0%-13.8%) over the four weeks, but was largely absent with CDDO-Im intervention. The toxicogenomic RNA expression signature characteristic of AFB1 was absent in the AFB1 + CDDO-Im-treated rats. The remarkable efficacy of CDDO-Im as an anticarcinogen is established even in the face of a significant aflatoxin adduct burden. Consequently, the absence of cancer requires a concept of a threshold for DNA damage for cancer development.

  13. Metabolism of aflatoxin B1 by normal human bronchial epithelial cells.

    PubMed

    Van Vleet, T R; Klein, P J; Coulombe, R A

    2001-08-10

    Aflatoxin B, (AFB1) is a potent hepatocarcinogen in animal models and a suspected carcinogen in humans. High concentrations of AFB, have been found in respirable grain dusts, and may therefore be a risk factor for human lung cancer in certain occupations. To study the potential for AFB, activation in human lung, cytochrome P-450 (CYP)-mediated activation and glutathione S-transferase (GST)-mediated detoxification of AFB1 were examined in cultured normal human bronchial epithelial (NHBE) cells. Cells were exposed to 0. 15 microM or 1.5 microM AFB, for 48 h and media was collected for metabolite analysis by high-performance liquid chromatography (HPLC). At 0. 15 microM, AFB1 was metabolized only to the detoxified metabolite aflatoxin Q1 (AFQ1). At 1.5 microM AFB1, both aflatoxin M1 (AFM1), and AFQ1 were produced. Cells pretreated with 50 degrees M 3-methylcholanthrene (3MC), a CYP 1A inducer, for 72 h prior to 0.15 microM AFB1, produced the activated AFB1 8,9-epoxide (AFBO). Similarly, microsomes prepared from 3MC-pretreated cells formed AFBO, but microsomes from noninduced cells did not. While AFB1-DNA adducts were not detected at low AFB1 concentrations in untreated NHBE, 3MC induction caused the production of AFB1-DNA adducts at 0.015 and 0.15 microM AFB1. Western immunoblots showed that the primary CYP isoforms responsible for AFB1 activation in the liver, 1A and 3A4, to be constitutively expressed in NHBE cells. Expression of CYP 1A was significantly increased in 3MC-pretreated cells, while CYP 3A4 expression increased slightly, but not to the extent of the 1A isoforms. The principal AFBO detoxifying enzyme, glutathione S-transferase (GST), was constitutively expressed in NHBE cells, and was increased approximately twofold by 3MC pretreatment. Cytosolic fractions from neither control nor 3MC-induced NHBE had measurable AFBO conjugating activity, indicating that these cells may lack AFB1-relevant GST activity. From these data, it appears that NHBE cells activate

  14. Detection of aflatoxin B1 in imported food products into Japan by enzyme-linked immunosorbent assay and high performance liquid chromatography.

    PubMed

    Adachi, Y; Hara, M; Kumazawa, N H; Hirano, K; Ueno, I; Egawa, K

    1991-02-01

    In order to detect the presence of aflatoxin B1 (AFB1), the use of the enzyme-linked immunosorbent assay (ELISA) and recovery test was evaluated. The detection limit of ELISA for AFB1 was 1 pg/assay and the recovery from maize spiked with AFB1 exceeded 80%. AFB1 was detected by ELISA in seven out of twelve samples of imported food products including peanut, almond, red pepper, cocoa bean, black pepper, buckwheat, walnut, adlay, soybean, popcorn, and pistachio nut, and by high performance liquid chromatography (HPLC) in four of the samples. However, the content of AFB1 in these samples was less than 10 ng/g of the minimum value authorized by the Japanese sanitation law. These results demonstrate that ELISA is more sensitive than HPLC and imported food products are broadly contaminated with AFB1.

  15. Aflatoxin B1, zearalenone and deoxynivalenol in feed ingredients and complete feed from central China.

    PubMed

    Liu, Jie; Sun, Lvhui; Zhang, Jiacai; Guo, Jiao; Chen, Lei; Qi, Desheng; Zhang, Niya

    2016-06-01

    Between 2012 and 2014, 2528 feed ingredient and complete feed samples were collected from central China. Numbers of 2083, 255 and 190 samples were analysed for aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON), respectively, by high-performance liquid chromatography in combination with UV or fluorescence detection. The incidence rates of AFB1, ZEN and DON contamination of feed ingredients and complete feeds were 33.9%, 90.2% and 77.4%, respectively. The percentage of positive samples for AFB1 ranged from 13.1% to 97.1%. Cottonseed meal presented the most serious contamination by AFB1. ZEN and DON contamination levels of feeds ranged from 50% to 100%, indicating serious contamination over the studied 3-year period. This study demonstrates that AFB1, ZEN and DON contamination of feeds in central China is serious and differs over the years. Feeds are mostly contaminated with ZEN, followed by DON and AFB1.

  16. Antioxidant efficacy of curcuminoids from turmeric ( Curcuma longa L.) powder in broiler chickens fed diets containing aflatoxin B1.

    PubMed

    Gowda, Nisarani K S; Ledoux, David R; Rottinghaus, Goerge E; Bermudez, Alex J; Chen, Yin C

    2009-12-01

    A 3-week-feeding study (1-21 d post-hatch) was conducted to evaluate the efficacy of total curcuminoids (TCMN), as an antioxidant, to ameliorate the adverse effects of aflatoxin B1 (AFB1) in broiler chickens. Turmeric powder (Curcuma longa L.) that contained 2.55 % TCMN was used as a source of TCMN. Six cage replicates of five chicks each were assigned to each of six dietary treatments, which included: basal diet; basal diet supplemented with 444 mg/kg TCMN; basal diet supplemented with 1.0 mg/kg AFB1; basal diet supplemented with 74 mg/kg TCMN and 1.0 mg/kg AFB1; basal diet supplemented with 222 mg/kg TCMN and 1.0 mg/kg AFB1; basal diet supplemented with 444 mg/kg TCMN and 1.0 mg/kg AFB1. The addition of 74 and 222 mg/kg TCMN to the AFB1 diet significantly (P < 0.05) improved weight gain and feed efficiency. Increase (P < 0.05) in relative liver weight in birds fed AFB1 was significantly reduced (P < 0.05) with the addition of 74, 222 and 444 mg/kg TCMN to the AFB1 diet. The inclusion of 222 mg/kg TCMN ameliorated the adverse effects of AFB1 on serum chemistry in terms of total protein, albumin and gamma-glutamyl transferase activity. The decreased antioxidant functions due to AFB1 were also alleviated by the inclusion of 222 mg/kg TCMN. It is concluded that the addition of 222 mg/kg TCMN to the 1.0 mg/kg AFB1 diet demonstrated maximum antioxidant activity against AFB1.

  17. Development of aflatoxin B1 aptasensor based on wide-range fluorescence detection using graphene oxide quencher.

    PubMed

    Joo, Minyoung; Baek, Seung Hoon; Cheon, Seon Ah; Chun, Hyang Sook; Choi, Sung-Wook; Park, Tae Jung

    2017-03-06

    Aflatoxin B1 (AFB1) is a carcinogenic substance produced by fungi of genus Aspergillus, especially Aspergillus flavus. Few nanograms of AFB1 that permeated through the skin is sufficient to cause liver cancer and stunted growth. In this study, a rapid aptamer-based assay for AFB1 was developed using the fluorescence quenching property of graphene oxide (GO) and a fluorescein amidite (FAM)-modified aptamer specific to AFB1. The aptamer, modified with the fluorescence dye FAM on its 5'-end, was used as a probe. Once bound by AFB1, a conformational change of the aptamer was caused that led to its interaction with the well-known fluorescence quencher GO, resulting in a decrease of the fluorescence intensity of the system. In the absence of AFB1, the fluorescence intensity remained unchanged. The aptamer-based AFB1 assay process was conducted through 3 steps within 40min. The aptamer was incubated with AFB1 before the addition of GO. The amount of AFB1 present was measured by the change in fluorescence intensity. The detection system was evaluated with standard solutions of AFB1 of various concentrations. The results showed that the fluorescence intensity decreased linearly as the concentration of AFB1 gradually increased. Although the assay was specific to AFB1, there was slight interference by other types of aflatoxin. When the assay was applied to a real sample, the limit of detection was 4.5 ppb, which was within the wide detection range of up to 300ppb with good linearity. Thus, this biosensor is considered to be competitive with the conventional detection methods in the field owing to its wide detection range and assay rapidity.

  18. Spectral characteristics of fluorescence and circular dichroism of aflatoxin B1 reaction with its anti-idiotypic antibody

    NASA Astrophysics Data System (ADS)

    Liu, Aiping; Yang, Hongxiu; Wang, Xiaohong; Chen, Fusheng

    2012-11-01

    Aflatoxin B1 (AFB1) is a toxic secondary metabolite and sensitive methods for its analysis have been developed. In our lab, a number of works have been carried out, including exploitation of detection methods and production of anti-idiotypic antibody (Ab2) against Fab fragment of anti-AFB1 antibody (Ab1). In this paper, Ab2 was generated upon the immunization of mice with F(ab')2 fragment, which was specific to AFB1 and obtained by pepsin digestion of Ab1. The characteristics of Ab2 was primarily investigated by indirect competitive enzyme-linked immunosorbent assay (icELISA), which indicated that Ab2, might bear an internal image of antigen AFB1 and was able to combine to F(ab')2 in competition with AFB1, and the concentration of Ab2 to cause 50% inhibition of binding (IC50) was 131.8 μg/mL. In addition, fluorescence and circular dichroism studies were designed to explore the mutual relationship among AFB1, F(ab')2 and Ab2. The fluorescence spectroscopy implied that both AFB1 and Ab2 act as a quencher upon F(ab')2, and the Ab2 could compete with AFB1 when both of Ab2 and AFB1 reacted with F(ab')2. The circular dichroism (CD) spectrum suggested that both the binding of Ab2 and AFB1 on F(ab')2 brought secondary conformation change of F(ab')2, especially in the changes of α helix and β sheet. The research performed would provide unique insight into the comprehension of interaction among AFB1, F(ab')2 and Ab2 as well as offer structural information for substitution researches of toxic antigen like AFB1.

  19. Protective role of vitamins A, C, and E against the genotoxic damage induced by aflatoxin B1 in cultured human lymphocytes.

    PubMed

    Alpsoy, L; Agar, G; Ikbal, M

    2009-04-01

    In this study, we aimed to evaluate the effect of vitamins A, C, and E against aflatoxin B1 (AFB1) on blood cultures in relation to induction of sister chromatid exchange (SCE). The results indicated genotoxic and mutagenic damage in cultured human lymphocytes exposed to AFB1. The results showed that 5 microM concentration of AFB1 increased SCE. When vitamins A, C, and E were added to AFB1, the frequency of SCE decreased. These results suggest that vitamins A, C, and E could effectively inhibit AFB1-induced SCE, which may partially responsible for its mutagenic effect of AFB1. Besides, the protective effect of vitamins A, C, and E against AFB1 was increased in a dose-dependent manner (i.e., as the doses increased, their protective effects also increased). There was a significant decrease in the SCE frequency in AFB1-treated group compared with the groups receiving AFB1 and also vitamins A, C, and E. The most effective concentration was 100 microM vitamin C, and the lowest effective concentration was 0.5 microM vitamin A. Vitamin C has the most effective concentration of 100 microM, and vitamin A has the lowest effective concentration of 0.5 microM. The order of the decreasing effect of the SCE frequency of vitamins was as follows: vitamin C > vitamin E > vitamin A.

  20. Systems responses of rats to aflatoxin B1 exposure revealed with metabonomic changes in multiple biological matrices.

    PubMed

    Zhang, Limin; Ye, Yangfang; An, Yanpeng; Tian, Yuan; Wang, Yulan; Tang, Huiru

    2011-02-04

    Exposure to aflatoxins causes liver fibrosis and hepatocellular carcinoma posing a significant health risk for human populations and livestock. To understand the mammalian systems responses to aflatoxin-B1 (AFB1) exposure, we analyzed the AFB1-induced metabonomic changes in multiple biological matrices (plasma, urine, and liver) of rats using (1)H NMR spectroscopy together with clinical biochemistry and histopathologic assessments. We found that AFB1 exposure caused significant elevation of glucose, amino acids, and choline metabolites (choline, phosphocholine, and glycerophosphocholine) in plasma but reduction of plasma lipids. AFB1 also induced elevation of liver lipids, amino acids (tyrosine, histidine, phenylalanine, leucine, isoleucine, and valine), choline, and nucleic acid metabolites (inosine, adenosine, and uridine) together with reduction of hepatic glycogen and glucose. AFB1 further caused decreases in urinary TCA cycle intermediates (2-oxoglutarate and citrate) and elevation of gut microbiota cometabolites (phenylacetylglycine and hippurate). These indicated that AFB1 exposure caused hepatic steatosis accompanied with widespread metabolic changes including lipid and cell membrane metabolisms, protein biosynthesis, glycolysis, TCA cycle, and gut microbiota functions. This implied that AFB1 exposure probably caused oxidative-stress-mediated impairments of mitochondria functions. These findings provide an overview of biochemical consequences of AFB1 exposure and comprehensive insights into the metabolic aspects of AFB1-induced hepatotoxicity in rats.

  1. Spiroethers of German chamomile inhibit production of aflatoxin G and trichothecene mycotoxin by inhibiting cytochrome P450 monooxygenases involved in their biosynthesis.

    PubMed

    Yoshinari, Tomoya; Yaguchi, Atsushi; Takahashi-Ando, Naoko; Kimura, Makoto; Takahashi, Haruo; Nakajima, Takashi; Sugita-Konishi, Yoshiko; Nagasawa, Hiromichi; Sakuda, Shohei

    2008-07-01

    The essential oil of German chamomile showed specific inhibition toward aflatoxin G(1) (AFG(1)) production, and (E)- and (Z)-spiroethers were isolated as the active compounds from the oil. The (E)- and (Z)-spiroethers inhibited AFG(1) production of Aspergillus parasiticus with inhibitory concentration 50% (IC(50)) values of 2.8 and 20.8 microM, respectively, without inhibiting fungal growth. Results of an O-methylsterigmatocystin (OMST) conversion study indicated that the spiroethers specifically inhibited the OMST to AFG(1) pathway. A cytochrome P450 monooxygenase, CYPA, is known as an essential enzyme for this pathway. Because CYPA has homology with TRI4, a key enzyme catalyzing early steps in the biosynthesis of trichothecenes, the inhibitory actions of the two spiroethers against TRI4 reactions and 3-acetyldeoxynivalenol (3-ADON) production were tested. (E)- and (Z)-spiroethers inhibited the enzymatic activity of TRI4 dose-dependently and interfered with 3-ADON production by Fusarium graminearum, with IC(50) values of 27.1 and 103 microM, respectively. Our results suggest that the spiroethers inhibited AFG(1) and 3-ADON production by inhibiting CYPA and TRI4, respectively.

  2. The efficacy of raw and concentrated bentonite clay in reducing the toxic effects of aflatoxin in broiler chicks.

    PubMed

    Shannon, T A; Ledoux, D R; Rottinghaus, G E; Shaw, D P; Daković, A; Marković, M

    2016-11-11

    The objective of this study was to evaluate the efficacy of two adsorbents, a raw bentonite clay (RC) and a concentrated bentonite clay (CC), in ameliorating the toxic effects of aflatoxin B1 (AFB1). Results of the in vitro study (pH 3.0) indicated the CC adsorbed more AFB1 than RC (93.39 mg/g vs. 79.30 mg/g) suggesting that CC may be more effective than RC in reducing the toxic effects of AFB1 One hundred and eighty day-old straight run broiler chicks were assigned to 6 replicate pens of 5 chicks each and assigned to 6 dietary treatments from hatch to day 21. Dietary treatments included: 1) basal diet (BD) containing no AFB1 or adsorbents; 2) BD plus 0.50% RC; 3) BD plus 0.50% CC; 4) BD plus 2.0 mg AFB1/kg; 5) BD plus 2.0 mg AFB1/kg plus 0.50% RC; and 6) BD plus 2.0 mg AFB1/kg plus 0.50% CC. Dietary AFB1 concentrations were confirmed by analysis and diets were screened for other mycotoxins prior to the start of the experiment. The addition of AFB1 to the feed reduced (P < 0.05) growth performance and increased (P < 0.05) relative liver weight (RLW) and kidney weight (RKW) of chicks fed AFB1 compared to control chicks on day 21. These changes were ameliorated (P < 0.05) by the addition of RC and CC to the AFB1 diet. Mild to moderate lesions of aflatoxicosis (2.25) were observed in chicks fed AFB1 alone on day 21. The addition of both RC and CC to the AFB1 diet decreased (P < 0.05) but did not prevent liver lesions (0.92 and 1.42, respectively). Results indicate that both RC and CC were effective in reducing the toxic effects of AFB1, however the cost of processing of CC would make the RC a more economical product for reducing the effects of AFB1 in young broiler chicks.

  3. Curcumin Successfully Inhibited the Computationally Identified CYP2A6 Enzyme-Mediated Bioactivation of Aflatoxin B1 in Arbor Acres broiler

    PubMed Central

    Muhammad, Ishfaq; Sun, Xiaoqi; Wang, He; Li, Wei; Wang, Xinghe; Cheng, Ping; Li, Sihong; Zhang, Xiuying; Hamid, Sattar

    2017-01-01

    Cytochrome P450 enzymes are often responsible for the toxic and carcinogenic effects of toxicants, such as aflatoxin B1 (AFB1). The human hepatic CYP2A6 enzyme mediates the oxidative metabolism of several procarcinogens. In this study, we characterized a partial sequence of CYP2A6 gene from Arbor Acres (AA) broiler and studied its role in AFB1 bioactivation. Moreover, the effect of curcumin on CYP2A6 is illustrated. Six groups of AA broiler were treated for 28 days including the control group (fed only basal diet), curcumin alone-treated group (450 mg/kg feed), the group fed AFB1-contaminated feed (5 mg/kg feed) plus the low (150 mg), medium (300 mg) or high (450 mg) of curcumin, and the group fed AFB1-contaminated diet alone (5 mg/kg feed). After the end of treatment period, liver samples were collected for different analyses. The results revealed that the histopathological examination showed clear signs of liver toxicity in AA broliers in AFB1-fed group, but curcumin-supplementation in feed prevented partially AFB1-induced liver toxicity. Liver and body weights were recorded to study the AFB1 harmful effects. We noted an obvious increase in liver weight and decrease in body weight in AFB1-fed group. But, the administration of curcumin partially ameliorated the increase in liver weight and decrease in body weight in a dose-dependent manner. The results (RT-PCR and Elisa) revealed that mRNA and protein expression level enhanced in AFB1-fed group. Consistently, CYP2A6 enzyme activity also increased in AFB1-fed group, suggesting that AA broiler CYP2A6 actively involved in bioactivation of AFB1. However, curcumin treatment inhibited CYP2A6 at mRNA and protein levels in AFB1 treated AA broiler in a dose-dependent manner. Maximum inhibition of liver CYP2A6 enzyme activity in AA broiler has been achieved at a dose of 450 mg/kg curcumin. This is the first study identifying and confirming the role of CYP2A6 enzyme in AFB1 bioactivation in AA broiler liver (in vivo), and

  4. Curcumin Successfully Inhibited the Computationally Identified CYP2A6 Enzyme-Mediated Bioactivation of Aflatoxin B1 in Arbor Acres broiler.

    PubMed

    Muhammad, Ishfaq; Sun, Xiaoqi; Wang, He; Li, Wei; Wang, Xinghe; Cheng, Ping; Li, Sihong; Zhang, Xiuying; Hamid, Sattar

    2017-01-01

    Cytochrome P450 enzymes are often responsible for the toxic and carcinogenic effects of toxicants, such as aflatoxin B1 (AFB1). The human hepatic CYP2A6 enzyme mediates the oxidative metabolism of several procarcinogens. In this study, we characterized a partial sequence of CYP2A6 gene from Arbor Acres (AA) broiler and studied its role in AFB1 bioactivation. Moreover, the effect of curcumin on CYP2A6 is illustrated. Six groups of AA broiler were treated for 28 days including the control group (fed only basal diet), curcumin alone-treated group (450 mg/kg feed), the group fed AFB1-contaminated feed (5 mg/kg feed) plus the low (150 mg), medium (300 mg) or high (450 mg) of curcumin, and the group fed AFB1-contaminated diet alone (5 mg/kg feed). After the end of treatment period, liver samples were collected for different analyses. The results revealed that the histopathological examination showed clear signs of liver toxicity in AA broliers in AFB1-fed group, but curcumin-supplementation in feed prevented partially AFB1-induced liver toxicity. Liver and body weights were recorded to study the AFB1 harmful effects. We noted an obvious increase in liver weight and decrease in body weight in AFB1-fed group. But, the administration of curcumin partially ameliorated the increase in liver weight and decrease in body weight in a dose-dependent manner. The results (RT-PCR and Elisa) revealed that mRNA and protein expression level enhanced in AFB1-fed group. Consistently, CYP2A6 enzyme activity also increased in AFB1-fed group, suggesting that AA broiler CYP2A6 actively involved in bioactivation of AFB1. However, curcumin treatment inhibited CYP2A6 at mRNA and protein levels in AFB1 treated AA broiler in a dose-dependent manner. Maximum inhibition of liver CYP2A6 enzyme activity in AA broiler has been achieved at a dose of 450 mg/kg curcumin. This is the first study identifying and confirming the role of CYP2A6 enzyme in AFB1 bioactivation in AA broiler liver (in vivo), and

  5. Protective Effects of Sporoderm-Broken Spores of Ganderma lucidum on Growth Performance, Antioxidant Capacity and Immune Function of Broiler Chickens Exposed to Low Level of Aflatoxin B1

    PubMed Central

    Liu, Tao; Ma, Qiugang; Zhao, Lihong; Jia, Ru; Zhang, Jianyun; Ji, Cheng; Wang, Xinyue

    2016-01-01

    This study was conducted to investigate the toxic effects of aflatoxin B1 (AFB1) and evaluate the effects of sporoderm-broken spores of Ganoderma lucidum (SSGL) in relieving aflatoxicosis in broilers. A total of 300 one-day-old male Arbor Acre broiler chickens were randomly divided into four dietary treatments; the treatment diets were: Control (a basal diet containing normal peanut meal); AFB1 (the basal diet containing AFB1-contaminated peanut meal); SSGL (basal diet with 200 mg/kg of SSGL); AFB1+SSGL (supplementation of 200 mg/kg of SSGL in AFB1 diet). The contents of AFB1 in AFB1 and AFB1+SSGL diets were 25.0 μg/kg in the starter period and 22.5 μg/kg in the finisher period. The results showed that diet contaminated with a low level of AFB1 significantly decreased (p < 0.05) the average daily feed intake and average daily gain during the entire experiment and reduced (p < 0.05) serum contents of total protein IgA and IgG. Furthermore, a dietary low level of AFB1 not only increased (p < 0.05) levels of hydrogen peroxide and lipid peroxidation, but also decreased (p < 0.05) total antioxidant capability, catalase, glutathione peroxidase, and hydroxyl radical scavenger activity in the liver and spleen of broilers. Moreover, the addition of SSGL to AFB1-contaminated diet counteracted these negative effects, indicating that SSGL has a protective effect against aflatoxicosis. PMID:27669305

  6. Intervention of Grape Seed Proanthocyanidin Extract on the Subchronic Immune Injury in Mice Induced by Aflatoxin B1

    PubMed Central

    Long, Miao; Zhang, Yi; Li, Peng; Yang, Shu-Hua; Zhang, Wen-Kui; Han, Jian-Xin; Wang, Yuan; He, Jian-Bin

    2016-01-01

    The aim was to investigate the prevention of grape seed proanthocyanidin extract (GSPE) on the subchronic immune injury induced by aflatoxin B1 (AFB1) and the possible ameliorating effect of GSPE in mice. The subchronic AFB1-induced immune injury mice model was set up with the continuous administration of 100 μg/kg body weight (BW) AFB1 for six weeks by intragastric administration. Then, intervention with different doses (50 and 100 mg/kg BW) of GSPE was conducted on mice to analyze the changes of body weight, immune organ index, antioxidant capability of spleen, serum immunoglobulin content, and the expression levels of inflammatory cytokines. The prevention of GSPE on the immune injury induced by AFB1 was studied. The GSPE could relieve the AFB1-induced reduction of body weight gain and the atrophy of the immune organ. The malondialdehyde (MDA) level of the spleen in the AFB1 model group significantly increased, but levels of catalase (CAT), glutathione (GSH), glutathione peroxidase (GSH-PX), and superoxide dismutase (SOD) significantly decreased. The GSPE could significantly inhibit the oxidative stress injury of the spleen induced by AFB1. AFB1 exposure could not significantly change the contents of IgA, IgG, or IgM. AFB1 significantly improved the expression of interleukin 1β (IL-1β), IL-6, tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ). Additionally, GSPE could decrease the expression of these four proinflammatory factors to different degrees and inhibit the inflammatory reaction of mice. The results suggest that GSPE alleviates AFB1-induced oxidative stress and significantly improves the immune injury of mice induced by AFB1. PMID:27070584

  7. In vivo treatment with aflatoxin B1 increases DNA oxidation, base excision repair activity and 8-oxoguanine DNA glycosylase 1 levels in mouse lung.

    PubMed

    Guindon-Kezis, Katherine A; Mulder, Jeanne E; Massey, Thomas E

    2014-07-03

    Carcinogenicity of the mycotoxin aflatoxin B1 (AFB1), which is produced by Aspergillus fungi, is associated with bioactivation of AFB1 to AFB1-8,9-exo-epoxide and formation of DNA adducts. However, AFB1 also causes 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in mouse lung DNA, suggesting that oxidative DNA damage may also contribute to AFB1 carcinogenicity. The oxidative DNA damage 5-hydroxy-2'-deoxycytidine (5-OHdC) may also contribute to AFB1 carcinogenicity. The objective of the present study was to determine the effect of treatment of mice with AFB1 on pulmonary and hepatic: 8-OHdG and 5-OHdC levels; base excision repair (BER, which repairs oxidative DNA damage) activities; and on levels of 8-oxoguanine DNA glycosylase (OGG1, the rate-limiting enzyme in the BER of 8-OHdG). Female A/J mice were treated with vehicle (dimethyl sulfoxide) or 50 mg/kg AFB1 ip. Oxidative DNA damage was measured using HPLC with electrochemical detection, BER activity was assessed using an in vitro assay that employs a substrate plasmid DNA with 8-OHdG lesions, and OGG1 protein levels were determined by immunoblotting. Two hours post treatment, AFB1 increased 8-OHdG levels in mouse lung DNA by approximately 69% relative to control (p<0.05), but did not alter 8-OHdG levels in liver or 5-OHdC levels in lung or liver (p>0.05). AFB1 treatment also increased BER activity in mouse lung by approximately 87% (p<0.05) but did not affect hepatic BER activity (p>0.05). Levels of OGG1 immunoreactive protein were increased in both lung (20%) and liver (60%) (p<0.05). These results are consistent with oxidative DNA damage contributing to the carcinogenicity of AFB1 in this model.

  8. Study of aflatoxin B1 and ochratoxin A production by natural microflora and Aspergillus parasiticus in black and green olives of Greek origin.

    PubMed

    Ghitakou, Stavroula; Koutras, Kostas; Kanellou, Eleni; Markaki, Panagiota

    2006-10-01

    Aflatoxin B1 (AFB1) is a carcinogenic metabolite produced by certain Aspergillus species. Ochratoxin A (OTA) is classified as "possible carcinogen" and it is a metabolite of Aspergillus ochraceus and Penicillium verrucosum. Fungi contaminate natural and processed olives which support AFB1 and OTA production. The aim of this study was to compare and investigate AFB1 and OTA production in three different varieties of damaged olives. For each variety two different treatments were applied: (1) olives with natural microflora and (2) olives inoculated with A. parasiticus after natural microflora elimination. AFB1 and OTA have been extracted simultaneously from olives, purified with immunoaffinity columns and quantitated by HPLC using fluorescence detector. The recoveries and detection limits of AFB1 and OTA were 94% and 0.15 ng AFB1 g(-1) and 102.7%, 0.41 ng OTA g(-1) respectively. Results showed that, meanwhile OTA was not found in any olive sample, AFB(1) production within the three varieties of olives with natural microflora was significantly (P< or =0.05) different regarding their substrate and time of incubation (18 days). AFB1 production in two different varieties of black olives after inoculation by A. parasiticus was not significantly higher compared with control samples. On the contrary, AFB1 production in green olives was stimulated after the 12th day. Additionally, investigation on the occurrence of AFB1 and OTA in 30 samples of olives and olive pasta from Athens market showed OTA's presence in two samples of olives contaminated at the levels of 1.18 and 1.86 ng OTA g(-1). Aflatoxin B1 was found at levels 0.15-1.13 ng AFB1 g(-1) in all samples tested.

  9. Effect of γ-radiation on the production of aflatoxin B1 by Aspergillus parasiticus in raisins (Vitis vinifera L.)

    NASA Astrophysics Data System (ADS)

    Kanapitsas, Alexandros; Batrinou, Anthimia; Aravantinos, Athanasios; Markaki, Panagiota

    2015-01-01

    Aflatoxin B1 (AFB1) mostly produced by Aspergillus flavus and Aspergillus parasiticus, is an extremely toxic and carcinogenic metabolite. The effect of gamma irradiation at dose of 10 kGy on the production of aflatoxin B1 (AFB1) inoculated by Aspergillus parasiticus in raisins (Vitis vinifera L.) and on AFB1 in contaminated samples, was investigated. Values of the amount of aflatoxin B1 produced on the 12th day of incubation, after irradiation, showed that gamma radiation exposure at 10 kGy decreased AFB1 production at 65% compared with the non-irradiated sample, on the same day. The application of 10 kGy gamma radiation directly on 100 ng of AFB1 which were spiked in raisins resulted in ~29% reduction of AFB1. According to the risk assessment analysis the Provisional Maximum Tolerable Daily Intake (PMTDI) of 1.0 ng AFB1 kg-1bw, indicates that consumers are less exposed to AFB1 from the irradiated raisins.

  10. The hepatoprotective effect of sea buckthorn (Hippophae rhamnoides) berries on induced aflatoxin B1 poisoning in chickens 1.

    PubMed

    Solcan, Carmen; Gogu, Mihaela; Floristean, Viorel; Oprisan, Bogdan; Solcan, Gheorghe

    2013-04-01

    The leaves and berries of sea buckthorn (SB; Hippophae rhamnoides; family Elaeagnaceae) are medically claimed as having phytoantioxidant, antiinflammatory, and anticancerous properties in humans. This study evaluated the hepatoprotective activity of oil from SB berries against toxicity induced by aflatoxin B1 (AFB1) in broiler chickens. The toxicity of AFB1 led to lower total serum proteins and specifically reduced albumin (P < 0.001). Serum aspartate aminotransferase increased from 191.14 ± 11.56 to 218.80 ± 13.68 (P < 0.001). When chickens were simultaneously dosed with AFB1 and an extract of SB berries, subsequent histology of the liver showed a significant reduction of necrosis and fatty formation compared with chickens treated with AFB1 alone. Immunohistochemical results indicated that COX2, Bcl-2, and p53 were highly expressed in the liver of AFB1-treated chickens and their expression was significantly reduced by SB oil supplementation. The levels of AFB1 residues in chickens livers were significantly reduced by SB oil from 460.92 ± 6.2 ng/mL in the AFB1 group to 15.59 ± 6.1 ng/mL in the AFB1 and SB oil group. These findings suggest that SB oil has a potent hepatoprotective activity, reducing the concentration of aflatoxins in liver and diminishing their adverse effects.

  11. The mitochondrial and endoplasmic reticulum pathways involved in the apoptosis of bursa of Fabricius cells in broilers exposed to dietary aflatoxin B1

    PubMed Central

    Fang, Jing; Liang, Na; Zhou, Mingqiang; Huang, Cheng; Peng, Xi

    2016-01-01

    Aflatoxin B1 (AFB1), a toxic metabolite produced by some fungi, exerts well-known hepatocarcinogenic and immunosuppressive effects, the latter can increase the apoptotic immune cells in vitro. However, it is largely unknown that which signaling pathways contribute to excessive apoptosis of immune cells which induced by AFB1. In this study, we investigated the roles of the mitochondria, endoplasmic reticulum (ER) and death receptor activated apoptotic pathways in the bursal of Fabricius (BF) cells in the broilers exposed to AFB1 diet. We found that (1) AFB1 diet induced morphological changes in the BF. (2) FCM and TUNEL methods showed that excessive apoptosis could be resulted from AFB1 intake. (3) AFB1-induced apoptosis of bursal cells involved mitochondrial pathway (increase of Bax, Bak, cytC, caspase-9, Apaf-1, caspase-3 and decrease of Bcl-2 and Bcl-xL) and ER pathway (increase of Grp78/Bip, Grp94 and CaM). (4) Oxidative stress was confirmed in the BF of chicken fed on AFB1 diet. Overall, this work is the first to demonstrate that the activation of mitochondria and ER apoptosis pathways can lead to excessive apoptosis in BF cells, and oxidative stress is a crucial driver during AFB1 exposure. PMID:27542244

  12. Aflatoxin B1 Degradation by Metabolites of Phoma glomerata PG41 Isolated From Natural Substrate Colonized by Aflatoxigenic Aspergillus flavus

    PubMed Central

    Shcherbakova, Larisa; Statsyuk, Natalia; Mikityuk, Oleg; Nazarova, Tatyana; Dzhavakhiya, Vitaly

    2015-01-01

    Background: Aflatoxin B1 (AFB1), produced by Aspergillus flavus, is one of the most life threatening food contaminants causing significant economic losses worldwide. Biological AFB1 degradation by microorganisms, or preferably microbial enzymes, is considered as one of the most promising approaches. Objectives: The current work aimed to study the AFB1-degrading metabolites, produced by Phoma glomerata PG41, sharing a natural substrate with aflatoxigenic A. flavus, and the preliminary determination of the nature of these metabolites. Materials and Methods: The AFB1-degrading potential of PG41 metabolites was determined by a quantitative high performance liquid chromatography (HPLC) of residual AFB1 after 72 hours incubation at 27ºC. The effects of pH, heat, and protease treatment on the AFB1-destroying activity of extracellular metabolites were examined. Results: The AFB1-degrading activity of protein-enriched fractions, isolated from culture liquid filtrate and cell-free extract, is associated with high-molecular-weight components, is time- and pH-dependent, thermolabile, and is significantly reduced by proteinase K treatment. The AFB1 degradation efficiency of these fractions reaches 78% and 66%, respectively. Conclusions: Phoma glomerata PG41 strain sharing natural substrate with toxigenic A. flavus secretes metabolites possessing a significant aflatoxin-degrading activity. The activity is associated mainly with a protein-enriched high-molecular-weight fraction of extracellular metabolites and appears to be of enzymatic origin. PMID:25789135

  13. Preparation and characterization of an immunoaffinity column for the selective extraction of aflatoxin B1 in 13 kinds of foodstuffs.

    PubMed

    Xie, Jie; Peng, Tao; He, Jian-Li; Shao, Yu; Fan, Chun-Lin; Chen, Ying; Jiang, Wen-Xiao; Chen, Min; Wang, Qi; Pei, Xing-Yao; Ding, Shuang-Yang; Jiang, Hai-Yang

    2015-08-15

    A rapid and reliable immunoaffinity column (IAC) clean-up based ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of aflatoxin B1 (AFB1) in cereals, peanuts, vegetable oils and Chinese traditional food products like sufu and lobster sauce. The immunoaffinity column of AFB1 (AFB1-IAC) was prepared by coupling CNBr-activated Sepharose-4B with the anti-AFB1 monoclonal antibody. The column capacity of IAC was over 260ng/mL gel. Samples were extracted with methanol-water (60:40, v/v) and the extracts were then purified on an AFB1-IAC before UPLC-MS/MS analysis. The average recoveries of AFB1 in spiked samples at levels of 1.0, 5.0 and 10.0μg/kg ranged from 72% to 98%, with the relative standard deviations of 1.2-9.3% (n=6). The limits of qualification ranged from 0.07 to 0.23μg/kg, which were below the MRLs of AFB1 in the matrices evaluated. In this work, the developed method was suitable for the determination of trace AFB1 residues in 13 kinds of foodstuffs.

  14. Integrated analysis of transcriptomics and metabonomics profiles in aflatoxin B1-induced hepatotoxicity in rat.

    PubMed

    Lu, Xiaoyan; Hu, Bin; Shao, Li; Tian, Yu; Jin, Tingting; Jin, Yachao; Ji, Shen; Fan, Xiaohui

    2013-05-01

    The aim of this work was to identify mechanisms and potential biomarkers for predicting the development and progression of aflatoxin B1 (AFB1)-induced acute hepatotoxicity. In this study, microarray analysis and metabolites profiles were used to identify shifts in gene expression and metabolite levels associated with the affected physiological processes of rats treated with AFB1. Histopathological examinations and serum biochemical analysis were simultaneously performed; the results indicated that hepatotoxicity occurred in higher dosage groups. However, gene expression analysis and metabolite profiles are more sensitive than general toxicity studies for detecting AFB1-induced acute hepatotoxicity as the patterns of low-dose AFB1-treated rats in these two technique platforms were more similar to the rats in higher dosage groups than to the control rats. Integrated analysis of the results from general toxicity studies, transcriptomics and metabonomics profiles suggested that p53 signaling pathway induced by oxidative damage was the crucial step in AFB1-induced acute hepatotoxicity, whereas gluconeogenesis and lipid metabolism disorder were found to be the major metabolic effects after acute AFB1 exposure. The genes and metabolites significantly affected in common in rat liver or serum of three doses AFB1 treatments served as potential biomarkers for detecting AFB1-induced acute hepatotoxicity.

  15. Aflatoxin B1 Risk Management in Parmigiano Reggiano Dairy Cow Feed

    PubMed Central

    Ricci, Barbara; Pizzamiglio, Valentina; Biancardi, Alberto; Piazza, Pierluigi; Merialdi, Giuseppe; Tosi, Giovanni; Giacometti, Federica; Nocetti, Marco; Fustini, Mattia; Serraino, Andrea; Formigoni, Andrea

    2016-01-01

    This study investigated aflatoxin B1 (AFB1) contamination in dairy cow feed and the risk management of AFB1 content in concentrates undertaken by feed industries in the Parmigiano Reggiano area. Data on aflatoxin contamination risk management applied in 29 feed industries were collected and the AFB1 content of 70 feed samples was analysed. Data were collected within the framework of a quality control programme promoted by the Parmigiano Reggiano Consortium in 2013 and 2014. Audit results showed that the control procedures to prevent AFB1 contamination mainly focused on maize and its by-products. AFB1 concentration resulted lower than 5 ppb [legal European Union (EU) limit] in all samples; in one out of 70 samples, AFB1 content was 3.8 ppb and in all the other samples it was lower than 3 ppb. Results showed that AFB1 risk management applied by Italian feed industries effectively monitors AFB1 levels in feed below the EU legal limit. PMID:27800427

  16. In vitro studies on chemoprotective effect of borax against aflatoxin B1-induced genetic damage in human lymphocytes.

    PubMed

    Turkez, Hasan; Geyikoğlu, Fatime; Dirican, Ebubekir; Tatar, Abdulgani

    2012-12-01

    A common dietary contaminant, aflatoxin B1 (AFB1), has been shown to be a potent mutagen and carcinogen in humans and many animal species. Since the eradication of AFB1 contamination in agricultural products has been rare, the use of natural or synthetic free radical scavengers could be a potential chemopreventive strategy. Boron compounds like borax (BX) and boric acid are the major components of industry and their antioxidant role has recently been reported. In the present report, we evaluated the capability of BX to inhibit the rate of micronucleus (MN) and sister chromatid exchange (SCE) formations induced by AFB1. There were significant increases (P < 0.05) in both SCE and MN frequencies of cultures treated with AFB1 (3.12 ppm) as compared to controls. However, co-application of BX (1, 2 and 5 ppm) and AFB1 resulted in decreases of SCE and MN rates as compared to the group treated with AFB1 alone. Borax gave 30-50 % protection against AFB1 induced SCEs and MNs. In conclusion, the support of borax was especially useful in aflatoxin-toxicated blood tissue. Thus, the risk on target tissues of AFB1 could be reduced and ensured early recovery from its toxicity.

  17. Metabolic effects of low aflatoxin B1 levels on broiler chicks.

    PubMed Central

    Maurice, D V; Bodine, A B; Rehrer, N J

    1983-01-01

    The effects of daily ingestion of aflatoxin B1 (AFB1) on growth, feed intake, plasma glucose, plasma cholesterol, plasma amino acids, plasma albumin, plasma ceruloplasmin, muscle amino acids, liver lipid, and bone strength were studied. For 3 weeks, beginning at an age of 2 days, broiler chicks were dosed daily per os with 50 or 100 micrograms of AFB1 per kg of body weight. Body weight and feed consumption were recorded daily, and metabolic responses were determined at 3 weeks. Treatment with AFB1 did not significantly alter body weight or feed intake. Relative liver weight showed a significant increase at the highest dose, with a significant concomitant increase in liver lipid and decrease in hepatic zinc. Relative spleen and heart weights were not affected by the toxin. Plasma glucose and cholesterol were significantly elevated at the highest dose. AFB1 significantly decreased plasma lysine and histidine and significantly increased muscle histidine, arginine, and valine. AFB1 decreased plasma albumin and markedly increased plasma ceruloplasmin. Dimensions of the long bones (femur and tibiotarsus) were not altered by the toxin. However, AFB1 caused a significant linear decline in the resistance of bone to breakage ("bone breaking strength"). The results indicate that low levels of AFB1 reduced bone strength in broiler chicks. The alterations in blood parameters indicated that AFB1 can disrupt metabolism even at low levels. PMID:6405694

  18. Co-occurence of aflatoxins and fumonisins in maize: guatemala as a case study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are found in maize. AFB1 is a genotoxic carcinogen (IARC Group 1) and FB1 a liver cancer promoter in rodents and trout (IARC Group 2B). Therefore, the possibility of co-exposure is a health concern, most notably in areas where maize serves as a dietary st...

  19. Aflatoxin B1 in sesame seeds and sesame products from the Greek market.

    PubMed

    Kollia, Eleni; Tsourouflis, Kyriakos; Markaki, Panagiota

    2016-09-01

    Aflatoxin B1 (AFB1) is considered as the most potent liver carcinogen for humans. A method for determination in sesame seeds was developed. AFB1 was extracted by methanol-water, cleaned by immunoaffinity columns and determined by high-performance liquid chromatography with fluorescence detection. The recovery factor and the limit of detection (LOD) of AFB1 in sesame seeds were 111.5% and 0.02 ng g(-1), respectively. Thirty samples of sesame products were examined for the presence of AFB1. After analysis, 77.6% of samples were found to be contaminated. Eight samples exceeded the European Union (EU) limit (2 µg AFB1 kg(-1)). In 15 samples, AFB1 was below the EU limit. Seven samples remained below the LOD. The most contaminated (14.49 ng AFB1 g(-1)) sample was unpeeled packaged sesame seeds. In all samples, aflatoxigenic Aspergilli fungi as well as the risk for AFB1 presence in sesame seed was investigated.

  20. Protective Effects of Sodium Selenite against Aflatoxin B1-Induced Oxidative Stress and Apoptosis in Broiler Spleen

    PubMed Central

    Wang, Fengyuan; Shu, Gang; Peng, Xi; Fang, Jing; Chen, Kejie; Cui, Hengmin; Chen, Zhengli; Zuo, Zhicai; Deng, Junliang; Geng, Yi; Lai, Weimin

    2013-01-01

    The aim of this study was to investigate the possible protective role of sodium selenite on aflatoxin B1-induced oxidative stress and apoptosis in spleen of broilers. Two hundred one-day-old male broilers, divided into five groups, were fed with basal diet (control group), 0.3 mg/kg AFB1 (AFB1 group), 0.3 mg/kg AFB1 + 0.2 mg/kg Se (+Se group I), 0.3 mg/kg AFB1 + 0.4 mg/kg Se (+Se group II) and 0.3 mg/kg AFB1 + 0.6 mg/kg Se (+Se group III), respectively. According to biochemical assays, AFB1 significantly decreased the activities of glutathione peroxidase, total superoxide dismutase, glutathione reductase, catalase and the level of glutathione hormone, while it increased the level of malondialdehyde. Moreover, AFB1 increased the percentage of apoptosis cells by flow cytometry and the occurrence of apoptotic cells by TUNEL assay. Simultaneous supplementation with sodium selenite restored these parameters to be close to those in control group. In conclusion, sodium selenite exhibited protective effects on AFB1-induced splenic toxicity in broilers by inhibiting oxidative stress and excessive apoptosis. PMID:23839060

  1. Effects of milk thistle seed against aflatoxin B1 in broiler model

    PubMed Central

    Amiridumari, Halimeh; Sarir, Hadi; Afzali, Nazar; FaniMakki, Omid

    2013-01-01

    Background: Consumption of aflatoxin B1 (AFB1) contaminated products can pose a risk of development of various diseases in human and animals due to radical production. The scope of this work is to evaluate the efficacy of milk thistle seed (MTS), as a radical scavenger, on serum biochemistry, lipid profile and liver enzymes against AFB1 in broiler chickens contaminated with AFB1. Materials and Methods: The effect of nine experimental treatments (3 × 3 factorial design) was assessed using 216 one-d-old Ross 308 male broiler chicks in a randomized complete design with four replicates of six birds for each dietary treatments: Control (T1), 250 ppb AFB1 (T2), 500 ppb AFB1 (T3), 0.5% MTS (T4), 0.5% MTS Plus 250 ppb AFB1 (T5), 0.5% MTS Plus 500 ppb AFB1 (T6), 1.0% MTS (T7), 1.0% MTS Plus 250 ppb AFB1 (T8), and 1.0% MTS Plus 500 ppb AFB1 (T9). The individual and combined effects of dietary AFB1 and MTS on serum biochemistry factors (Glucose, Calcium, Phosphorus, Iron, Creatinine, and Uric acid), lipid profile (Triglyceride, Cholesterol, Low density lipoprotein (LDL), and High density lipoprotein (HDL)) and liver enzymes aspartate amino-transferase and alanine amino-transaminase (ALT) in broilers were evaluated at 21 days of age. Also, statistical packages Macros-1.002 (2010) were used to perform the above analysis on computer. Results: Consumption of 500 ppb AFB1 in to the diet significantly decreased HDL (58.13 ± 2.65), Calcium (7.11 ± 0.13), and Glucose (197.1 ± 7.42) compared to the control group (85.12 ± 1.95, 9.45 ± 0.17 and 223.1 ± 6.61, respectively), (P < 0.05). In contrast, it significantly increased creatinine (2.25 ± 0.011) and AST (244.51 ± 4.91). Using MTS together with AFB1 significantly reduced the effect of AFB1 on the above parameters. Conclusion: MTS can provide protection against the negative effects of AFB1 on broiler chicks. PMID:24381623

  2. Metabolomics of the Bio-Degradation Process of Aflatoxin B1 by Actinomycetes at an Initial pH of 6.0

    PubMed Central

    Eshelli, Manal; Harvey, Linda; Edrada-Ebel, RuAngelie; McNeil, Brian

    2015-01-01

    Contamination of food and feed by Aflatoxin B1 (AFB1) is a cause of serious economic and health problems. Different processes have been used to degrade AFB1. In this study, biological degradation of AFB1 was carried out using three Actinomycete species, Rhodococcus erythropolis ATCC 4277, Streptomyces lividans TK 24, and S. aureofaciens ATCC 10762, in liquid cultures. Biodegradation of AFB1 was optimised under a range of temperatures from 25 to 40 °C and pH values of 4.0 to 8.0. An initial concentration of 20 µg/mL of AFB1 was used in this study. The amount of AFB1 remaining was measured against time by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC), coupled with UV and mass spectrometry (LC-MS). All species were able to degrade the AFB1, and no significant difference was found between them. AFB1 remained in the liquid culture for R. erythropolis, S. lividans and S. aureofaciens were 0.81 µg/mL, 2.41 µg/mL and 2.78 µg/mL respectively, at the end of the first 24 h. Degradation occurred at all incubation temperatures and the pH with the optimal conditions for R. erythropolis was achieved at 30 °C and pH 6, whereas for S. lividans and S. aureofaciens the optimum conditions for degradation were 30 °C and pH 5. Analysis of the degradative route indicated that each microorganism has a different way of degrading AFB1. The metabolites produced by R. erythropolis were significantly different from the other two microorganisms. Products of degradation were identified through metabolomic studies by utilizing high-resolution mass spectral data. Mass spectrometric analysis indicated that the degradation of AFB1 was associated with the appearance of a range of lower molecular weight compounds. The pathway of degradation or chemical alteration of AFB1 was followed by means of high resolution Fourier transform mass spectrometry (HR-FTMS) analysis as well as through the MS2 fragmentation to unravel the degradative pathway for AFB1. AFB1 bio

  3. Cytochrome P450 2A13 enhances the sensitivity of human bronchial epithelial cells to aflatoxin B1-induced DNA damage

    SciTech Connect

    Yang, Xuejiao; Zhang, Zhan; Wang, Xichen; Wang, Yun; Zhang, Xiaoming; Lu, Huiyuan; Wang, Shou-Lin

    2013-07-15

    Cytochrome P450 2A13 (CYP2A13) mainly expresses in human respiratory system and mediates the metabolic activation of aflatoxin B1 (AFB1). Our previous study suggested that CYP2A13 could increase the cytotoxic and apoptotic effects of AFB1 in immortalized human bronchial epithelial cells (BEAS-2B). However, the role of CYP2A13 in AFB1-induced DNA damage is unclear. Using BEAS-2B cells that stably express CYP2A13 (B-2A13), CYP1A2 (B-1A2), and CYP2A6 (B-2A6), we compared their effects in AFB1-induced DNA adducts, DNA damage, and cell cycle changes. BEAS-2B cells that were transfected with vector (B-vector) were used as a control. The results showed that AFB1 (5–80 nM) dose- and time-dependently induced DNA damage in B-2A13 cells. AFB1 at 10 and 80 nM significantly augmented this effect in B-2A13 and B-1A2 cells, respectively. B-2A6 cells showed no obvious DNA damage, similar to B-vector cells and the vehicle control. Similarly, compared with B-vector, B-1A2 or B-2A6 cells, B-2A13 cells showed more sensitivity in AFB1-induced γH2AX expression, DNA adduct 8-hydroxy-deoxyguanosine formation, and S-phase cell-cycle arrest. Furthermore, AFB1 activated the proteins related to DNA damage responses, such as ATM, ATR, Chk2, p53, BRCA1, and H2AX, rather than the proteins related to DNA repair. These effects could be almost completely inhibited by 100 μM nicotine (a substrate of CYP2A13) or 1 μM 8-methoxypsoralen (8-MOP; an inhibitor of CYP enzyme). Collectively, these findings suggest that CYP2A13 plays an important role in low-concentration AFB1-induced DNA damage, possibly linking environmental airborne AFB1 to genetic injury in human respiratory system. - Highlights: • CYP2A13 plays a critical role in low concentration of AFB1-induced DNA damage. • B-2A13 cells were more sensitive to AFB1 than B-1A2 cells and B-2A6 cells. • AFB1 dose- and time-dependently induced DNA damage in B-2A13 cells • AFB1-induced DNA adducts and damage can be inhibited by nicotine and 8

  4. A novel aflatoxin-binding Bacillus probiotic: Performance, serum biochemistry, and immunological parameters in Japanese quail.

    PubMed

    Bagherzadeh Kasmani, F; Karimi Torshizi, M A; Allameh, A; Shariatmadari, F

    2012-08-01

    Two experiments were performed to screen bacilli isolated from quails for their aflatoxin removal potential and to assess the efficiency of their amelioration of experimental aflatoxicosis. Nonhemolytic bacilli were selected for in vitro aflatoxin B1 (AFB1) removal and conventional probiotic tests. The isolate with the highest scores was selected for assessment in field experiments and was identified as Berevibacillus laterosporus (Bl). In the second experiment, 125 male Japanese quails (21 d old) were divided into 5 groups with 5 replications to compare the toxin removal efficiency of Bl with that of a commercial toxin binder, improved Millbond-TX (IMTX). The experimental groups were as follows: Control (without any feed additive or AFB1); AFB1 (2.5 mg/kg); AFB1+Bl (2.5 mg/kg+10(8) cfu/mL); AFB1+IMTX (2.5 mg/kg+2.5 g/kg); and Bl (10(8) cfu/mL). The greatest BW gain and slaughter and carcass weights were found in the Bl group and the lowest values were observed in the AFB1 group (P<0.05). Feeding AFB1 alone to the chicks resulted in a significant decrease in serum albumin, total protein, and glucose and cholesterol levels but a significant increase in serum uric acid, urea, creatinin and phosphorus (P<0.05). Treatment of birds on AFB1 with Bl restored these to their original levels (P<0.05). AFB1+Bl-fed birds had serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and alkaline phosphatase enzyme activity similar to control birds (P<0.05). Antibody titer against Newcastle disease virus was found to be lowest in the AFB1 group but highest in the Bl group (P<0.05). Antibody production against sheep red blood cells was lower in the AFB1 group compared with the AFB1+Bl group (P<0.05). Berevibacillus laterosporus supplementation of the AFB1 diet restored the skin response to 2,4-dinitro 1-chlorobenzene to levels comparable with control birds (P<0.05). It can be concluded that selected indigenous Bl is a promising probiotic with AFB1 removal

  5. Zinc inhibits aflatoxin B1-induced cytotoxicity and genotoxicity in human hepatocytes (HepG2 cells).

    PubMed

    Yang, Xuan; Lv, Yangjun; Huang, Kunlun; Luo, Yunbo; Xu, Wentao

    2016-06-01

    Aflatoxin B1 (AFB1) has strong carcinogenicity. Consumption of AFB1-contaminated agricultural products and the occurrence of hepatocellular carcinoma have received widespread attention. The aim of this paper was to investigate whether zinc supplementation could inhibit AFB1-induced cytotoxicity and genotoxicity in HepG2 cells and the mechanism of this inhibition. Our data suggest that zinc sources can relieve a certain degree of AFB1-induced cytotoxicity and genotoxicity by protecting against apoptotic body formation and DNA strand breaks, affecting S phase cell cycle arrest, reducing 8-OHdG formation, inhibiting global DNA hypomethylation and regulating gene expression in antioxidation, zinc-association and apoptosis processes. Consequently, zinc stabilizes the integrity of DNA and improves cell survival. These data provides new insights into the protective role of zinc in alleviating AFB1-induced cytotoxicity and mediating epigenetic changes in hepatocytes, demonstrating that zinc sources have detoxification properties in mycotoxin-induced toxicity.

  6. Performance improvement of the one-dot lateral flow immunoassay for aflatoxin B1 by using a smartphone-based reading system.

    PubMed

    Lee, Sangdae; Kim, Giyoung; Moon, Jihea

    2013-04-18

    This study was conducted to develop a simple, rapid, and accurate lateral flow immunoassay (LFIA) detection method for point-of-care diagnosis. The one-dot LFIA for aflatoxin B1 (AFB1) was based on the modified competitive binding format using competition between AFB1 and colloidal gold-AFB1-BSA conjugate for antibody binding sites in the test zone. A Smartphone-based reading system consisting of a Samsung Galaxy S2 Smartphone, a LFIA reader, and a Smartphone application for the image acquisition and data analysis. The detection limit of one-dot LFIA for AFB1 is 5 μg/kg. This method provided semi-quantitative analysis of AFB1 samples in the range of 5 to 1,000 μg/kg. Using combination of the one-dot LFIA and the Smartphone-based reading system, it is possible to conduct a more fast and accurate point-of-care diagnosis.

  7. The aflatoxin B1 -fumonisin B1 toxicity in BRL-3A hepatocytes is associated to induction of cytochrome P450 activity and arachidonic acid metabolism.

    PubMed

    Mary, Verónica S; Arias, Silvina L; Otaiza, Santiago N; Velez, Pilar A; Rubinstein, Héctor R; Theumer, Martín G

    2017-02-09

    Human oral exposure to aflatoxin B1 (AFB1 ) and fumonisin B1 (FB1 ) is associated with increased hepatocellular carcinoma. Although evidence suggested interactive AFB1 -FB1 hepatotoxicity, the underlying mechanisms remain mostly unidentified. This work was aimed at evaluating the possible AFB1 -FB1 interplay to induce genetic and cell cycle toxicities in BRL-3A rat hepatocytes, reactive oxygen species (ROS) involvement, and the AFB1 metabolizing pathways cytochrome P450 (CYP) and arachidonic acid (ArAc) metabolism as ROS contributors. Flow cytometry of stained BRL-3A hepatocytes was used to study the cell cycle (propidium iodide), ROS intracellular production (DCFH-DA, HE, DAF-2 DA), and phospholipase A activity (staining with bis-BODIPY FL C11-PC). The CYP1A activity was assessed by the 7-ethoxyresorufin-O-deethylase (EROD) assay. Despite a 48-h exposure to FB1 (30 μM) not being genotoxic, the AFB1 (20 μM)-induced micronucleus frequency was overcome by the AFB1 -FB1 mixture (MIX), presumably showing toxin interaction. The mycotoxins blocked G1/S-phase, but only MIX caused cell death. Overall, the oxidative stress led these alterations as the pretreatment with N-acetyl-l-cysteine reduced such toxic effects. While AFB1 had a major input to the MIX pro-oxidant activity, with CYP and ArAc metabolism being ROS contributors, these pathways were not involved in the FB1 -elicited weak oxidative stress. The MIX-induced micronucleus frequency in N-acetyl-l-cysteine pretreated cells was greater than that caused by AFB1 without antioxidants, suggesting enhanced AFB1 direct genotoxicity probably owing to the higher CYP activity and ArAc metabolism found in MIX. The metabolic pathways modulation by AFB1 -FB1 mixtures could raise its hepatocarcinogenic properties.

  8. Efficacy of sodium bentonite as a detoxifier of broiler feed contaminated with aflatoxin and fumonisin.

    PubMed

    Miazzo, R; Peralta, M F; Magnoli, C; Salvano, M; Ferrero, S; Chiacchiera, S M; Carvalho, E C Q; Rosa, C A R; Dalcero, A

    2005-01-01

    Sodium bentonite (SB) was evaluated for its ability to reduce the deleterious effects of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in broiler diets. It was incorporated into the diets (0.3%) containing 2.5 mg/kg AFB1, 200 mg/kg FB1, or a combination of 2.5 mg/kg AFB1 and 200 mg/kg FB1. Aflatoxin B1 significantly diminished body weight gain, whereas FB1 or the combination of FB1 and SB had no effect. Addition of SB in the diets significantly diminished the inhibitory effects of dietary AFB1. Feeding AFB1 alone caused significant increases in the relative weights of most observed organs. Feeding FB1 alone did not alter relative weights of any organs. In the combined diet (AFB1 plus FB1) relative weights of the liver, kidney, gizzard, and spleen were increased. Addition of SB to the diet containing AFB1 diminished the relative weights of liver, kidney, and spleen. Addition of SB to diets containing AFB1 and FB1 only decreased liver weights. In relation to the control, lower serum levels of total protein, albumin, and globulins were observed for all AFB, containing diets without SB addition, whereas all other treatments were not altered. Livers of birds fed diets containing AFB1 and a combination of AFB1 and FB1 were enlarged, yellowish, friable, and had rounded borders. The histopathology of them, stained with hematoxylin and eosin, showed multifocal and varied cytoplasmatic vacuolization with perilobular location. Incorporation of SB reduced the incidence and severity of the hepatic histopathology changes associated with aflatoxicosis.

  9. Reduction of Aflatoxin B1 Toxicity by Lactobacillus plantarum C88: A Potential Probiotic Strain Isolated from Chinese Traditional Fermented Food “Tofu”

    PubMed Central

    Huang, Li; Duan, Cuicui; Zhao, Yujuan; Gao, Lei; Niu, Chunhua; Xu, Jingbo; Li, Shengyu

    2017-01-01

    In this study, we investigated the potential of Lactobacillus plantarum isolated from Chinese traditional fermented foods to reduce the toxicity of aflatoxin B1 (AFB1), and its subsequent detoxification mechanism. Among all the investigated L. plantarum strains, L. plantarum C88 showed the strongest AFB1 binding capacity in vitro, and was orally administered to mice with liver oxidative damage induced by AFB1. In the therapy groups, the mice that received L. plantarum C88, especially heat-killed L. plantarum C88, after a single dose of AFB1 exposure, showed an increase in unabsorbed AFB1 in the feces. Moreover, the effects of L. plantarum C88 on the enzymes and non-enzymes antioxidant abilities in serum and liver, histological alterations of liver were assayed. The results indicated that compared to the control group, L. plantarum C88 alone administration induced significant increase of antioxidant capacity, but did not induce any significant changes in the histological picture. Compared to the mice that received AFB1 only, L. plantarum C88 treatment could weaken oxidative stress by enhancing the activity of antioxidant enzymes and elevating the expression of Glutathione S-transferase (GST) A3 through Nuclear factor erythroid (derived factor 2) related factor 2 (Nrf2) pathway. Furthermore, cytochrome P450 (CYP 450) 1A2 and CYP 3A4 expression was inhibited by L. plantarum C88, and urinary aflatoxin B1-N7-guanine (AFB-N7-guanine), a AFB1 metabolite formed by CYP 1A2 and CYP 3A4, was significantly reduced by the presence of viable L. plantarum C88. Meanwhile, the significant improvements were showed in histological pictures of the liver tissues in mice orally administered with viable L. plantarum C88. Collectively, L. plantarum C88 may alleviate AFB1 toxicity by increasing fecal AFB1 excretion, reversing deficits in antioxidant defense systems and regulating the metabolism of AFB1. PMID:28129335

  10. Reduction of Aflatoxin B1 Toxicity by Lactobacillus plantarum C88: A Potential Probiotic Strain Isolated from Chinese Traditional Fermented Food "Tofu".

    PubMed

    Huang, Li; Duan, Cuicui; Zhao, Yujuan; Gao, Lei; Niu, Chunhua; Xu, Jingbo; Li, Shengyu

    2017-01-01

    In this study, we investigated the potential of Lactobacillus plantarum isolated from Chinese traditional fermented foods to reduce the toxicity of aflatoxin B1 (AFB1), and its subsequent detoxification mechanism. Among all the investigated L. plantarum strains, L. plantarum C88 showed the strongest AFB1 binding capacity in vitro, and was orally administered to mice with liver oxidative damage induced by AFB1. In the therapy groups, the mice that received L. plantarum C88, especially heat-killed L. plantarum C88, after a single dose of AFB1 exposure, showed an increase in unabsorbed AFB1 in the feces. Moreover, the effects of L. plantarum C88 on the enzymes and non-enzymes antioxidant abilities in serum and liver, histological alterations of liver were assayed. The results indicated that compared to the control group, L. plantarum C88 alone administration induced significant increase of antioxidant capacity, but did not induce any significant changes in the histological picture. Compared to the mice that received AFB1 only, L. plantarum C88 treatment could weaken oxidative stress by enhancing the activity of antioxidant enzymes and elevating the expression of Glutathione S-transferase (GST) A3 through Nuclear factor erythroid (derived factor 2) related factor 2 (Nrf2) pathway. Furthermore, cytochrome P450 (CYP 450) 1A2 and CYP 3A4 expression was inhibited by L. plantarum C88, and urinary aflatoxin B1-N7-guanine (AFB-N7-guanine), a AFB1 metabolite formed by CYP 1A2 and CYP 3A4, was significantly reduced by the presence of viable L. plantarum C88. Meanwhile, the significant improvements were showed in histological pictures of the liver tissues in mice orally administered with viable L. plantarum C88. Collectively, L. plantarum C88 may alleviate AFB1 toxicity by increasing fecal AFB1 excretion, reversing deficits in antioxidant defense systems and regulating the metabolism of AFB1.

  11. Curcumin Prevents Aflatoxin B1 Hepatoxicity by Inhibition of Cytochrome P450 Isozymes in Chick Liver

    PubMed Central

    Zhang, Ni-Ya; Qi, Ming; Zhao, Ling; Zhu, Ming-Kun; Guo, Jiao; Liu, Jie; Gu, Chang-Qin; Rajput, Shahid Ali; Krumm, Christopher Steven; Qi, De-Sheng; Sun, Lv-Hui

    2016-01-01

    This study was designed to establish if Curcumin (CM) alleviates Aflatoxin B1 (AFB1)-induced hepatotoxic effects and to determine whether alteration of the expression of cytochrome P450 (CYP450) isozymes is involved in the regulation of these effects in chick liver. One-day-old male broilers (n = 120) were divided into four groups and used in a two by two factorial trial in which the main factors included supplementing AFB1 (< 5 vs. 100 μg/kg) and CM (0 vs. 150 mg/kg) in a corn/soybean-based diet. Administration of AFB1 induced liver injury, significantly decreasing albumin and total protein concentrations and increasing alanine aminotransferase and aspartate aminotransferase activities in serum, and induced hepatic histological lesions at week 2. AFB1 also significantly decreased hepatic glutathione peroxidase, catalase, and glutathione levels, while increasing malondialdehyde, 8-hydroxydeoxyguanosine, and exo-AFB1-8,9-epoxide (AFBO)-DNA concentrations. In addition, the mRNA and/or activity of enzymes responsible for the bioactivation of AFB1 into AFBO—including CYP1A1, CYP1A2, CYP2A6, and CYP3A4—were significantly induced in liver microsomes after 2-week exposure to AFB1. These alterations induced by AFB1 were prevented by CM supplementation. Conclusively, dietary CM protected chicks from AFB1-induced liver injury, potentially through the synergistic actions of increased antioxidant capacities and inhibition of the pivotal CYP450 isozyme-mediated activation of AFB1 to toxic AFBO. PMID:27834912

  12. Interactive effects of dietary protein concentration and aflatoxin B1 on performance, nutrient digestibility, and gut health in broiler chicks.

    PubMed

    Chen, X; Naehrer, K; Applegate, T J

    2016-06-01

    A 20-day trial was conducted to determine the impact of aflatoxin B1 (AFB1) and dietary protein concentration on performance, nutrient digestibility, and gut health in broiler chicks. The 6 dietary treatments were arranged in a 2 × 3 factorial with 3 crude protein (CP) concentrations (16, 22, and 26%) with or without 1.5 mg/kg AFB1 Each diet was fed to 6 replicate cages (6 chicks per cage) from zero to 20 d of age. Endogenous N and amino acid loss were estimated from birds fed a N-free diet with or without 1.5 mg/kg AFB1 A significant interaction between AFB1 and CP concentration was observed for growth performance, where reduction of BW gain, feed intake, gain:feed ratio, and breast muscle weight by AFB1 were most profound in birds fed the 16%-CP diet, and were completely eliminated when birds were fed the 26%-CP diet (AFB1 by CP interaction; P ≤ 0.023). Similarly, AFB1 reduced serum albumin, total protein, and globulin concentrations in birds fed 16 and 22% CP diets, but not in those fed the 26%-CP (AFB1 by CP interaction; P ≤ 0.071). Gut permeability was increased in birds fed AFB1-contamiated diets as measured by serum lactulose/rhamnose ratio (main effect; P = 0.04). Additionally, AFB1 tended to increase endogenous N loss (P = 0.09), and significantly reduced apparent ileal digestible energy and standardized ileal N and amino acid digestibility in birds fed the 16%-CP diet, while birds fed higher dietary CP were not affected (AFB1 by CP interaction; P ≤ 0.01). Further, AFB1 increased the translation initiation factor 4E-binding protein (4EBP1), claudin1, and multiple jejunal amino acid transporters expression (main effect; P ≤ 0.04). Results from this study indicate that a 1.5 mg AFB1/kg diet significantly impairs growth, major serum biochemistry measures, gut barrier, endogenous loss, and energy and amino acid digestibility. Aflatoxicosis can be augmented by low dietary CP, while higher dietary CP completely eliminated the impairment of

  13. Efficacy of beer fermentation residue containing Saccharomyces cerevisiae cells for ameliorating aflatoxicosis in broilers.

    PubMed

    Bovo, F; Franco, L T; Kobashigawa, E; Rottinghaus, G E; Ledoux, D R; Oliveira, C A F

    2015-05-01

    This study aimed to determine the aflatoxin B1 (AFB1) binding capacity of a beer fermentation residue (BFR) containing Saccharomyces cerevisiae cells, and the efficacy of BFR to ameliorate the toxic effects of AFB1 on performance, serum biochemistry, and histology of broilers. The BFR was collected from a microbrewery, and the yeast cells were counted, dried, and milled before it was used in the study. In vitro evaluation of the BFR was conducted using different concentrations of AFB1 (2.0, 4.0, 8.0, 16.0, and 32.0 μg AFB1/mL) and 100 mg/10 mL of BFR at pH 3.0 or 6.0. Two hundred 1-day-old male broilers (Ross 308) were assigned to chick batteries and allowed ad libitum access to feed and water. A completely randomized design was used with 5 replicate pens of 5 chicks assigned to each of 4 dietary treatments from hatch to 21 d, which included: 1) basal diet (BD), with no BFR or AFB1; 2) BD supplemented with 1% BFR; 3) BD supplemented with 2 mg AFB1/kg of feed; and 4) BD supplemented with 2 mg AFB1/kg feed and 1% BFR. Performance variables were determined weekly, while serum analyses were performed on d 14 and 21. At the end of the study, chicks were anesthetized with carbon dioxide, euthanized by cervical dislocation, and the kidney, liver, and bursa of Fabricius were removed for determination of relative weights, and for histological evaluation. In vitro assays showed that the higher the initial AFB1 concentration in solution, the greater the AFB1 amount adsorbed by BFR at both pHs tested. Feed intake, BW gain, and concentrations of albumin, total protein, and globulin increased (P < 0.05) in broilers fed BFR+AFB1 (Diet 4), when compared to the birds receiving only AFB1 (Diet 2). Although BFR was not able to reduce or prevent the effects of AFB1 on relative weights of kidneys and liver, it reduced the severity of histological changes in the liver and kidney caused by AFB1.

  14. Aflatoxin B1 affects apoptosis and expression of Bax, Bcl-2, and Caspase-3 in thymus and bursa of fabricius in broiler chickens.

    PubMed

    Peng, Xi; Chen, Kejie; Chen, Jin; Fang, Jing; Cui, Hengmin; Zuo, Zhicai; Deng, Junliang; Chen, Zhengli; Geng, Yi; Lai, Weimin

    2016-09-01

    Aflatoxin B1 is known as a mycotoxin that develops various health problems of animals, the effects of AFB1 on thymus and bursa of Fabricius in chickens are not clear. The objective of this study was to investigate the apoptosis of thymus and bursa of Fabricius in broilers fed with AFB1 . Two hundred Avian broilers were randomly divided into four groups of 50 each, namely control group and three AFB1 groups fed with 0.15 mg, 0.3 mg, and 0.6 mg AFB1 /kg diet, respectively. In this study, flow cytometer and immunohistochemical approaches were used to determine the percentage of apoptotic cells and the expression of Bax, Bcl-2, and Caspase-3. The results showed that consumption of AFB1 diets results in increased percentage of apoptotic cells and increased expression of Caspase-3 in both thymus and bursa of Fabricius. The expression of Bax was increased and the expression of Bcl-2 was decreased in the thymus, but no significant changes in Bax and Bcl-2 expression were observed in the bursa of Fabricius when broilers fed with AFB1 . These findings suggest that adverse effects of AFB1 on thymus and bursa of Fabricius in broilers were confirmed by increased apoptotic cells and abnormal expression of Caspase-3. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1113-1120, 2016.

  15. Effects of Lipoic Acid on Immune Function, the Antioxidant Defense System, and Inflammation-Related Genes Expression of Broiler Chickens Fed Aflatoxin Contaminated Diets

    PubMed Central

    Li, Yan; Ma, Qiu-Gang; Zhao, Li-Hong; Wei, Hua; Duan, Guo-Xiang; Zhang, Jian-Yun; Ji, Cheng

    2014-01-01

    This study was designed to evaluate the effect of low level of Aflatoxin B1 (AFB1) on oxidative stress, immune reaction and inflammation response and the possible ameliorating effects of dietary alpha-lipoic acid (α-LA) in broilers. Birds were randomly allocated into three groups and assigned to receive different diets: basal diet, diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in diet containing 74 μg/kg AFB1 for three weeks. The results showed that the serum levels of malondialdehyde, tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ) in the AFB1-treated group were significantly increased than the control group. In addition, the increased expressions of interleukin 6 (IL6), TNFα and IFNγ were observed in birds exposed to the AFB1-contaminated diet. These degenerative changes were inhibited by α-LA-supplement. The activities of total superoxide dismutase and glutathione peroxidase, the levels of humoral immunity, and the expressions of nuclear factor-κB p65 and heme oxygenase-1, however, were not affected by AFB1. The results suggest that α-LA alleviates AFB1 induced oxidative stress and immune changes and modulates the inflammatory response at least partly through changes in the expression of proinflammatory cytokines of spleen such as IL6 and TNFα in broiler chickens. PMID:24699046

  16. Degradation of aflatoxin B(1) by cell-free extracts of Rhodococcus erythropolis and Mycobacterium fluoranthenivorans sp. nov. DSM44556(T).

    PubMed

    Teniola, O D; Addo, P A; Brost, I M; Färber, P; Jany, K-D; Alberts, J F; van Zyl, W H; Steyn, P S; Holzapfel, W H

    2005-11-25

    Biological degradation of aflatoxin B(1) (AFB(1)) by Rhodococcus erythropolis was examined in liquid cultures and in cell-free extracts. Dramatic reduction of AFB(1) was observed during incubation in the presence of R. erythropolis cells (17% residual AFB(1) after 48 h and only 3-6% residual AFB(1) after 72 h). Cell-free extracts of four bacterial strains, R. erythropolis DSM 14,303, Nocardia corynebacterioides DSM 12,676, N. corynebacterioides DSM 20,151, and Mycobacterium fluoranthenivorans sp. nov. DSM 44,556(T) were produced by disrupting cells in a French pressure cell. The ability of crude cell-free extracts to degrade AFB(1) was studied under different incubation conditions. Aflatoxin B(1) was effectively degraded by cell free extracts of all four bacterial strains. N. corynebacterioides DSM 12,676 (formerly erroneously classified as Flavobacterium aurantiacum) showed the lowest degradation ability (60%) after 24 h, while >90% degradation was observed with N. corynebacterioides DSM 20,151 over the same time. R. erythropolis and M. fluoranthenivorans sp. nov. DSM 44,556(T) have shown more than 90% degradation of AFB(1) within 4 h at 30 degrees C, whilst after 8 h AFB(1) was practicably not detectable. The high degradation rate and wide temperature range for degradation by R. erythropolis DSM 14,303 and M. fluoranthenivorans sp. nov. DSM 44,556(T) indicate potential for application in food and feed processing.

  17. Comparative Efficacy of Silymarin and Choline Chloride (Liver Tonics) in Preventing the Effects of Aflatoxin B1 in Bovine Calves.

    PubMed

    Naseer, O; Khan, J A; Khan, M S; Omer, M O; Chishti, G A; Sohail, M L; Saleem, M U

    2016-09-01

    Aflatoxins are secondary metabolites produced by Aspergillus spp. which are injurious to animals and humans The aim of this study was to determine the effects of aflatoxin B1 (AFB1) on Average Daily Feed Intake (ADFI), Average Daily Weight Gain (ADWG), haematological and serum biochemical responses of Bovine Calves and to determine the comparative efficacy of two different liver tonics against AFB1. Twenty seven calves were selected from herd and divided into 3 groups. All calves were fed with 1.0 mg/kg AFB1 for a period of 10 days. After that they were fed with liver tonics: Silymarin fed at a rate of 600 mg/kg and Choline chloride 500 mg/kg for 7 days. The results indicate that the ADFI and ADWG of AFB1 treated calves decreased significantly. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine significantly increased due to AFB1. In haematology the total erythrocyte count (TEC), total leukocyte count (TLC), haemoglobin concentration (HGB), haematocrit levels (HCT), mean corpuscular haemoglobin (MCH), mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCHC), lymphocyte %, neutrophil % and monocyte % significantly decreased in AFB1 treated calves after 10 days of feeding. Both liver tonics significantly (p<0.05) improved all the parameters, including ADFI, ADWG, hematologial and serum biochemical test. However, Silymarin comparatively more efficiently ameliorate the effects induced by AFB1 than choline chloride.

  18. Cobalt-Porphyrin-Platinum-Functionalized Reduced Graphene Oxide Hybrid Nanostructures: A Novel Peroxidase Mimetic System For Improved Electrochemical Immunoassay

    PubMed Central

    Shu, Jian; Qiu, Zhenli; Wei, Qiaohua; Zhuang, Junyang; Tang, Dianping

    2015-01-01

    5,10,15,20-Tetraphenyl-21H,23H-porphine cobalt flat stacking on the reduced graphene oxide with platinum nanoparticles (PtNPs/CoTPP/rGO) were first synthesized and functionalized with monoclonal rabbit anti-aflatoxin B1 antibody (anti-AFB1) for highly efficient electrochemical immunoassay of aflatoxin B1 (AFB1) in this work. Transmission electron microscopy (TEM), atomic force microscope (AFM) and spectral techniques were employed to characterize the PtNPs/CoTPP/rGO hybrids. Using anti-AFB1-conjugated PtNPs/CoTPP/rGO as the signal-transduction tag, a novel non-enzymatic electrochemical immunosensing system was designed for detection of target AFB1 on the AFB1-bovine serum albumin-functionalized sensing interface. Experimental results revealed that the designed immunoassay could exhibit good electrochemical responses for target analyte and allowed the detection of AFB1 at a concentration as low as 5.0 pg mL−1 (5.0 ppt). Intra- and inter-assay coefficients of variation were below 10%. Importantly, the methodology was further validated for analyzing naturally contaminated or spiked blank peanut samples with consistent results obtained by AFB1 ELISA kit, thus providing a promising approach for quantitative monitoring of organic pollutants. PMID:26462136

  19. Detoxification of Aflatoxin B1 by Zygosaccharomyces rouxii with Solid State Fermentation in Peanut Meal

    PubMed Central

    Zhou, Guanghui; Chen, Yujie; Kong, Qing; Ma, Yunxiao; Liu, Yang

    2017-01-01

    Aflatoxins are highly carcinogenic, teratogenetic, and morbigenous secondary metabolites of Aspergillus flavus and A. parasiticus that can contaminate multiple staple foods, such as peanut, maize, and tree nuts. In this study, Zygosaccharomyces rouxii was screened out and identified from fermented soy paste—one kind of traditional Chinese food—to detoxify aflatoxin B1 (AFB1) by aerobic solid state fermentation in peanut meal. The optimal degradation condition was chosen from single factor experiment, and the most effective detoxification rate was about 97%. As for liquid fermentation, we tested the binding ability of Z. rouxii, and the highest binding rate reached was 74.3% (nonviable cells of Z. rouxii) in phosphate-buffered saline (PBS). Moreover, the biotransformation of AFB1 through fermentation of Z. rouxii in peanut meal was further verified by liquid chromatography/mass spectrometry (LC/MS). According to TIC scan, after fermentation by Z. rouxii, the AFB1 in peanut meal was prominently degraded to the lowering peaks of AFB1. Additionally, m/s statistics demonstrated that AFB1 may be degraded to some new products whose structural properties may be different from AFB1, or the degradation products may be dissolved in the aqueous phase rather than the organic phase. As far as we know, this is the first report indicating that the safe strain of Z. rouxii has the ability to detoxify AFB1. PMID:28117705

  20. Cobalt-Porphyrin-Platinum-Functionalized Reduced Graphene Oxide Hybrid Nanostructures: A Novel Peroxidase Mimetic System For Improved Electrochemical Immunoassay

    NASA Astrophysics Data System (ADS)

    Shu, Jian; Qiu, Zhenli; Wei, Qiaohua; Zhuang, Junyang; Tang, Dianping

    2015-10-01

    5,10,15,20-Tetraphenyl-21H,23H-porphine cobalt flat stacking on the reduced graphene oxide with platinum nanoparticles (PtNPs/CoTPP/rGO) were first synthesized and functionalized with monoclonal rabbit anti-aflatoxin B1 antibody (anti-AFB1) for highly efficient electrochemical immunoassay of aflatoxin B1 (AFB1) in this work. Transmission electron microscopy (TEM), atomic force microscope (AFM) and spectral techniques were employed to characterize the PtNPs/CoTPP/rGO hybrids. Using anti-AFB1-conjugated PtNPs/CoTPP/rGO as the signal-transduction tag, a novel non-enzymatic electrochemical immunosensing system was designed for detection of target AFB1 on the AFB1-bovine serum albumin-functionalized sensing interface. Experimental results revealed that the designed immunoassay could exhibit good electrochemical responses for target analyte and allowed the detection of AFB1 at a concentration as low as 5.0 pg mL-1 (5.0 ppt). Intra- and inter-assay coefficients of variation were below 10%. Importantly, the methodology was further validated for analyzing naturally contaminated or spiked blank peanut samples with consistent results obtained by AFB1 ELISA kit, thus providing a promising approach for quantitative monitoring of organic pollutants.

  1. Effects of aflatoxin B(1) and fumonisin B(1) on blood biochemical parameters in broilers.

    PubMed

    Tessari, Eliana N C; Kobashigawa, Estela; Cardoso, Ana Lúcia S P; Ledoux, David R; Rottinghaus, George E; Oliveira, Carlos A F

    2010-04-01

    The individual and combined effects of dietary aflatoxin B(1 )(AFB(1)) and fumonisin B(1) (FB(1)) on liver pathology, serum levels of aspartate amino-transferase (AST) and plasma total protein (TP) of broilers were evaluated from 8 to 41 days of age. Dietary treatments included a 3 × 3 factorial arrangement with three levels of AFB(1 )(0, 50 and 200 μg AFB(1)/kg), and three levels of FB(1 )(0, 50 and 200 mg FB(1)/kg). At 33 days post feeding, with the exception of birds fed 50 mg FB(1 )only, concentrations of AST were higher (p < 0.05) in all other treatment groups when compared with controls. Plasma TP was lower (p < 0.05) at six days post feeding in groups fed 200 μg AFB(1)/kg alone or in combination with FB(1). At day 33 days post feeding, with the exception of birds fed the highest combination of AFB(1 )and FB(1 )which had higher plasma TP than control birds(, )plasma TP of birds fed other dietary treatments were similar to controls. Broilers receiving the highest levels of AFB(1) and FB(1) had bile duct proliferation and trabecular disorder in liver samples. AFB(1) singly or in combination with FB at the levels studied, caused liver damage and an increase in serum levels of AST.

  2. Aflatoxin B1-Induced Developmental and DNA Damage in Caenorhabditis elegans

    PubMed Central

    Feng, Wei-Hong; Xue, Kathy S.; Tang, Lili; Williams, Phillip L.; Wang, Jia-Sheng

    2016-01-01

    Aflatoxin B1 (AFB1) is a ubiquitous mycotoxin produced by toxicogenic Aspergillus species. AFB1 has been reported to cause serious adverse health effects, such as cancers and abnormal development and reproduction, in animals and humans. AFB1 is also a potent genotoxic mutagen that causes DNA damage in vitro and in vivo. However, the link between DNA damage and abnormal development and reproduction is unclear. To address this issue, we examined the DNA damage, germline apoptosis, growth, and reproductive toxicity following exposure to AFB1, using Caenorhabditis elegans as a study model. Results found that AFB1 induced DNA damage and germline apoptosis, and significantly inhibited growth and reproduction of the nematodes in a concentration-dependent manner. Exposure to AFB1 inhibited growth or reproduction more potently in the DNA repair-deficient xpa-1 nematodes than the wild-type N2 strain. According to the relative expression level of pathway-related genes measured by real-time PCR, the DNA damage response (DDR) pathway was found to be associated with AFB1-induced germline apoptosis, which further played an essential role in the dysfunction of growth and reproduction in C. elegans. PMID:28035971

  3. Protective Effect of Selenium on Aflatoxin B1-Induced Testicular Toxicity in Mice.

    PubMed

    Cao, Zheng; Shao, Bing; Xu, Feibo; Liu, Yunfeng; Li, Yanfei; Zhu, Yanzhu

    2017-03-27

    Aflatoxins have been considered as one of the major risk factors of male infertility, and aflatoxin B1 (AFB1) is the most highly toxic and prevalent member of the aflatoxins family. Selenium (Se), an essential nutritional trace mineral for normal testicular development and male fertility, has received extensive intensive on protective effects of male reproductive system due to its potential antioxidant and activating testosterone synthesis. To investigate the protective effect of Se on AFB1-induced testicular toxicity, the mice were orally administered with AFB1 (0.75 mg/kg) and Se (0.2 mg/kg or 0.4 mg/kg) for 45 days. We found that that Se elevated testes index, sperm functional parameters (concentration, malformation, and motility), and the level of serum testosterone in AFB1-exposed mice. Moreover, our results showed that Se attenuated the AFB1-induced oxidative stress and the reduction of testicular testosterone synthesis enzyme protein expression such as steroidogenic acute regulatory protein (StAR), P450 side-chain cleavage (P450scc), and 17β-hydroxysteroid dehydrogenase (17β-HSD) in AFB1-exposed mice. These results demonstrated that Se conferred protection against AFB1-induced testicular toxicity and can be attributed to its antioxidant and increased testosterone level by stimulating protein expression of StAR and testosterone synthetic enzymes.

  4. Distinct response of the hepatic transcriptome to Aflatoxin B1 induced hepatocellular carcinogenesis and resistance in rats

    PubMed Central

    Shi, Jiejun; He, Jiangtu; Lin, Jing; Sun, Xin; Sun, Fenyong; Ou, Chao; Jiang, Cizhong

    2016-01-01

    Aflatoxin is a natural potent carcinogen and a major cause of liver cancer. However, the molecular mechanisms of hepatocellular carcinogenesis remain largely unexplored. In this study, we profiled global gene expression in liver tissues of rats that developed hepatocellular carcinoma (HCC) from aflatoxin B1 (AFB1) administration and those that were AFB1-resistant, as well as rats without AFB1 exposure as a control. AFB1 exposure resulted in extensive perturbation in gene expression with different functions in HCC and AFB1 resistance (AR) samples. The differentially expressed genes (DEGs) in HCC sample were enriched for cell proliferation, cell adhesion and vasculature development that largely contribute to carcinogenesis. Anti-apoptosis genes were up-regulated in HCC sample whereas apoptosis-induction genes were up-regulated in AR sample. AFB1 exposure also caused extensive alteration in expression level of lncRNAs. Among all the 4511 annotated lncRNAs, half of them were highly expressed only in HCC sample and up-regulated a group of protein-coding genes with cancer-related functions: apoptosis regulation, DNA repair, and cell cycle. Intriguingly, these genes were down-regulated by lncRNAs highly expressed in AR sample. Collectively, apoptosis is the critical biological process for carcinogenesis in response to AFB1 exposure through changes in expression level of both protein-coding and lncRNA genes. PMID:27545718

  5. Genotoxicity of Aflatoxin B1 and Ochratoxin A after simultaneous application of the in vivo micronucleus and comet assay.

    PubMed

    Corcuera, Laura-Ana; Vettorazzi, Ariane; Arbillaga, Leire; Pérez, Noemí; Gil, Ana Gloria; Azqueta, Amaya; González-Peñas, Elena; García-Jalón, Jose Antonio; López de Cerain, Adela

    2015-02-01

    Aflatoxin B1 (AFB1) and Ochratoxin A (OTA) are genotoxic mycotoxins that can contaminate a variety of foodstuffs, the liver and the kidney being their target organs, respectively. The micronucleus (MN) assay (bone marrow) and the comet assay (liver and kidney) were performed simultaneously in F344 rats, treated with AFB1 (0.25 mg/kg b.w.), OTA (0.5 mg/kg b.w.) or both mycotoxins. After AFB1 treatment, histopathology and biochemistry analysis showed liver necrosis, focal inflammation and an increase in Alanine Aminotransferase and Aspartate Aminotransferase. OTA alone did not cause any alteration. The acute hepatotoxic effects caused by AFB1 were less pronounced in animals treated with both mycotoxins. With regard to the MN assay, after 24 h, positive results were obtained for AFB1 and negative results were obtained for OTA, although both toxins caused bone marrow toxicity. In the combined treatment, OTA reduced the toxicity and the number of MN produced by AFB1. In the comet assay, after 3 h, positive results were obtained for AFB1 in the liver and for OTA in the kidney. The combined treatment reduced DNA damage in the liver and had no influence in the kidney. Altogether, these results may be indicative of an antagonistic relationship regarding the genotoxicity of both mycotoxins.

  6. Hematological Parameters and the State of Liver Cells of Rats After Oral Administration of Aflatoxin B1 Alone and Together with Nanodiamonds

    NASA Astrophysics Data System (ADS)

    Mogilnaya, O. A.; Puzyr, A. P.; Baron, A. V.; Bondar, V. S.

    2010-05-01

    Hematological parameters and the state of liver cells of rats were examined in vivo after the animals received aflatoxin B1 (AfB1) alone and together with modified nanodiamonds (MND) synthesized by detonation. The rats that had received the MND hydrosol had elevated leukocyte levels, mainly due to higher granulocyte counts and somewhat increased monocyte counts compared to control rats. Hematological parameters of the rats that had received AfB1 alone differed from those of the control rats in another way: total white blood cell counts were significantly lower due to the decreased lymphocyte counts. In rats that had consumed AfB1 with the MND hydrosol, changes in hematological parameters were less pronounced than in rats that had consumed either AfB1 or MND. Electron microscopy showed that hepatocytes of the rats that had received the MND hydrosol or AfB1 with the MND hydrosol contained elevated levels of lipid inclusions and lysosomes. Hyperplasia of the smooth endoplasmic reticulum (EPR) was revealed in liver specimens of the rats that had received AfB1. Results of the study suggest the conclusion about mutual mitigation of the effects of nanoparticles and the mycotoxin on rats blood and liver cells after AfB1 has adsorbed on MND.

  7. Effects of lipoic acid on immune function, the antioxidant defense system, and inflammation-related genes expression of broiler chickens fed aflatoxin contaminated diets.

    PubMed

    Li, Yan; Ma, Qiu-Gang; Zhao, Li-Hong; Wei, Hua; Duan, Guo-Xiang; Zhang, Jian-Yun; Ji, Cheng

    2014-04-02

    This study was designed to evaluate the effect of low level of Aflatoxin B1 (AFB1) on oxidative stress, immune reaction and inflammation response and the possible ameliorating effects of dietary alpha-lipoic acid (α-LA) in broilers. Birds were randomly allocated into three groups and assigned to receive different diets: basal diet, diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in diet containing 74 μg/kg AFB1 for three weeks. The results showed that the serum levels of malondialdehyde, tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ) in the AFB1-treated group were significantly increased than the control group. In addition, the increased expressions of interleukin 6 (IL6), TNFα and IFNγ were observed in birds exposed to the AFB1-contaminated diet. These degenerative changes were inhibited by α-LA-supplement. The activities of total superoxide dismutase and glutathione peroxidase, the levels of humoral immunity, and the expressions of nuclear factor-κB p65 and heme oxygenase-1, however, were not affected by AFB1. The results suggest that α-LA alleviates AFB1 induced oxidative stress and immune changes and modulates the inflammatory response at least partly through changes in the expression of proinflammatory cytokines of spleen such as IL6 and TNFα in broiler chickens.

  8. Enzyme-controlled dissolution of MnO2 nanoflakes with enzyme cascade amplification for colorimetric immunoassay.

    PubMed

    Lai, Wenqiang; Wei, Qiaohua; Xu, Mingdi; Zhuang, Junyang; Tang, Dianping

    2017-03-15

    A new colorimetric immunosensing platform accompanying enzyme cascade amplification strategy was fabricated for quantitative screening of small-molecular mycotoxins (aflatoxin B1, AFB1 used in this case) coupling with enzyme-controlled dissolution of MnO2 nanoflakes. The visual colored assay was executed by high-efficient MnO2-3,3',5,5'-tetramethylbenzidine (TMB) system (blue). In the presence of ascorbic acid, MnO2 nanoflakes were dissolved into Mn(2+) ions, thus resulting in a perceptible color change from blue to colorless. The reaction could be weakened through ascorbate oxidase to catalyze ascorbic acid into dehydroascorbic acid, which indirectly depended on the concentration of ascorbate oxidase. By using ascorbate oxidase/ anti-AFB1 antibody-labeled gold nanoparticles, a novel competitive-type colorimetric enzyme immunoassay was developed for detection of AFB1 on AFB1-bovine serum albumin (BSA)-conjugated magnetic beads. Upon addition of target AFB1, the analyte competed with the conjugated AFB1-BSA on the magnetic beads for the labeled anti-AFB1 antibody on the gold nanoparticles. Under optimal conditions, the absorbance decreased with increasing target AFB1 within the dynamic range of 0.05-150ngmL(-1) with a detection limit of 6.5pgmL(-1) at the 3Sblank level. The precision and specificity of the MnO2-TMB-based immunosensing system were acceptable. In addition, method accuracy was further validated for monitoring spiked peanut samples, giving results matched well with those obtained from commercialized AFB1 ELISA kit.

  9. Augmentation of aflatoxin B1 hepatotoxicity by endotoxin: involvement of endothelium and the coagulation system.

    PubMed

    Luyendyk, James P; Copple, Bryan L; Barton, Charles C; Ganey, Patricia E; Roth, Robert A

    2003-03-01

    Aflatoxin B(1) (AFB(1)) is a fungal toxin that causes both acute hepatotoxicity and liver carcinoma in exposed humans and animals. Previous studies have shown that exposure of rats to nontoxic doses of bacterial lipopolysaccharide (LPS) augments AFB(1) acute hepatotoxicity, resulting in enhanced injury to hepatic parenchymal cells and bile ducts. At larger doses, LPS causes damage to sinusoidal endothelial cells (SECs) and activation of the coagulation system. Accordingly, we tested the hypothesis that treatment of rats with AFB(1) and LPS damages SECs and activates the coagulation system, which is critical for potentiation of AFB(1) hepatotoxicity by LPS. Male, Sprague-Dawley rats were given 1 mg/kg AFB(1) (ip), then 4 hours later 7.4 x 10(6) EU/kg LPS was administered (iv). A time-dependent injury to SECs and parenchymal cells was observed in AFB(1)/LPS-cotreated animals that became significant by 12 h, as estimated by increases in plasma hyaluronic acid (HA) and alanine aminotransferase (ALT) activities, respectively. Immunohistochemical analysis revealed that endothelial cell immunostaining was decreased in both centrilobular and periportal regions after AFB(1)/LPS treatment. Immunohistochemical evidence of fibrin deposition was found in both centrilobular and periportal regions by 12 h, but these deposits persisted only in periportal regions by 24 h. Administration of the anticoagulant heparin to AFB(1)/LPS-cotreated animals markedly attenuated increases in markers of hepatic parenchymal cell injury but provided only minimal amelioration of bile duct injury. These results suggest that AFB(1)/LPS coexposure results in SEC injury and activation of the coagulation system, and that the coagulation system is required for the development of hepatic parenchymal cell injury but not bile duct injury in this model.

  10. Impact of dietary branched chain amino acids concentration on broiler chicks during aflatoxicosis.

    PubMed

    Chen, X; Zhang, Q; Applegate, T J

    2016-06-01

    A 20-day trial was conducted to determine the effects of dietary branched-chain amino acids (BCAA) on performance, nutrient digestibility, and gene expression of the mTOR pathway in broiler chicks when exposed to aflatoxin B1 (AFB1). The 6 dietary treatments were arranged in a 2 × 3 factorial with 3 BCAA concentrations (1.16, 1.94, and 2.73%) with or without 1.5 mg/kg AFB1 (1.77 mg/kg analyzed). Each diet was fed to 8 replicate cages (6 chicks per cage) from 6 to 20 d of age. Exposure to AFB1 significantly reduced gain:feed ratio and breast muscle weight (P < 0.05), and tended to decrease cumulative BW gain (P = 0.087), while increasing dietary BCAA improved all performance measures (P ≤ 0.0002), except relative breast muscle weight. Apparent ileal digestibility of N and 9 amino acids were increased by AFB1 (P ≤ 0.05), but were reduced by higher dietary BCAA (P ≤ 0.023). Jejunum histology was not affected by AFB1, while higher dietary BCAA tended to increase villus height (P = 0.08). Additionally, the gene expression of mTOR pathway (mTOR, 4EBP1, and S6K1) from liver and jejunum were not affected by dietary treatments, while muscle expression of S6K1 tended to be increased by AFB1 (P = 0.07). No significant interaction between AFB1 and dietary BCAA were observed for any measures in the current study. Results from this study suggested that feed AFB1 contamination can significantly reduce growth performance and breast muscle growth in broiler chicks at 20 d. Higher BCAA supply may have beneficial impact on bird performance, but this effect is independent of AFB1 exposure.

  11. Efficiency of hydrated sodium calcium aluminosilicate to ameliorate the adverse effects of graded levels of aflatoxin B1 in broiler chicks.

    PubMed

    Chen, X; Horn, N; Applegate, T J

    2014-08-01

    The objective of this study was to evaluate the efficiency of a hydrated sodium calcium aluminosilicate (HSCAS) adsorbent to ameliorate the adverse effects of 0.5 to 2 mg of aflatoxin B1 (AFB1)/kg in broiler chicks. The study consisted of 8 dietary treatments, including 4 concentrations of AFB1 (0, 0.5, 1, and 2 mg/kg) with or without HSCAS (0.5%) fed to 8 replicate cages per diet (6 males chicks per cage) from 0 to 21 d of age. Cumulative feed intake, BW gain (P < 0.0001), and G:F (P = 0.004) of birds fed the 2 mg of AFB1/kg of diet were significantly lower in comparison with birds fed 0 to 1 mg of AFB1/kg. Relative liver weight was increased in the 2 mg of AFB1/kg group (P < 0.0001). Dietary HSCAS improved cumulative BW gain (main effect P = 0.06), particularly from 14 to 21 d of age (P = 0.037). Dietary HSCAS also reversed the increase in relative liver weight for birds fed AFB1 (P = 0.019). Dietary AFB1 negatively affected major serum parameters (albumin, total protein, globulin, phosphorus, glucose, alkaline phosphatase, and creatine phosphokinase), whereas supplementation with HSCAS partially alleviated the affected serum biochemistry. In addition, serum complement activity and liver gene expression were negatively affected by 2 mg of AFB1/kg. The HSCAS supplement increased the liver expression of catalase and superoxide dismutase (P < 0.05). Results from this study indicate that dietary supplementation with HSCAS can effectively improve BW gain and partially ameliorate aflatoxicosis for broiler chicks fed AFB1-contaminated feeds.

  12. Efficacy of adsorbents (bentonite and diatomaceous earth) and turmeric (Curcuma longa) in alleviating the toxic effects of aflatoxin in chicks.

    PubMed

    Dos Anjos, F R; Ledoux, D R; Rottinghaus, G E; Chimonyo, M

    2015-01-01

    A study was conducted to determine the efficacy of bentonite clay (BC), diatomaceous earth (DE) and turmeric powder (TUM) in alleviating the toxic effects of aflatoxin B1 (AFB1). A total of 250 Ross-308 d-old male broiler chicks were assigned to 10 dietary treatments (5 replicates of 5 chicks) from hatch to d 21. Dietary treatments were: basal diet; basal diet plus AFB1 (2 mg) or BC (0.75%), or DE (0.75%), or TUM (200 mg/kg curcuminoids) and different combinations of AFB1, BC, DE and TUM. Feed intake (FI), body weight gain (BWG) and feed gain (FG) of the birds fed on BC or DE separately were not different from control birds. Birds fed on TUM only had similar FI and FG but lower BWG than control chicks. Aflatoxin B1 reduced FI, BWG and serum concentrations of glucose, albumin, total protein calcium, but increased FG and relative liver and kidney weights. Chicks fed on the combination of AFB1 and BC had similar FI and FG to control chicks. Chicks fed on the combination of DE and AFB1 had lower FI (23.1%) and BWG (28.6%) compared with control chicks. Chicks fed on the combination of TUM and AFB1 also had decreased FI (26.2 %) and BWG (31%) compared with control chicks. Chicks fed on the combination of AFB1, BC and TUM consumed significantly higher amounts of feed compared with chicks fed on only AF, but gained less when compared with control diet chicks. Chicks fed on the combination of AFB1, DE and TUM diet had poorer growth performance than those fed on AFB1 alone. None of the combination diets reduced the severity of liver lesions.

  13. In Vitro Efficacy of Myxococcus fulvus ANSM068 to Biotransform Aflatoxin B1

    PubMed Central

    Guan, Shu; Zhao, Lihong; Ma, Qiugang; Zhou, Ting; Wang, Ning; Hu, Xinxu; Ji, Cheng

    2010-01-01

    Aflatoxin B1 (AFB1) is commonly found in cereals and animal feeds and causes a significant threat to the food industry and animal production. Several microbial isolates with high AFB1 transformation ability have been identified in our previous studies. The aim of this research was to characterize one of those isolates, Myxococcus fulvus ANSM068, and to explore its biotransformation mechanism. The bacterial isolate of M. fulvus ANSM068, isolated from deer feces, was able to transform AFB1 by 80.7% in liquid VY/2 medium after incubation at 30 °C for 72 h. The supernatant of the bacterial culture was more effective in transforming AFB1 as compared to the cells alone and the cell extract. The transformation activity was significantly reduced and eradicated after the culture supernatant was treated with proteinase K, proteinase K plus SDS and heating. Culture conditions, including nitrogen source, initial pH and incubation temperature were evaluated for an optimal AFB1 transformation. Liquid chromatography mass spectrometry (LCMS) analyses showed that AFB1 was transformed to a structurally different compound. Infrared analysis (IR) indicated that the lactone ring on the AFB1 molecule was modified by the culture supernatant. Chromatographies on DEAE-Ion exchange and Sephadex-Molecular sieve and SDS-PAGE electrophoresis were used to determine active components from the culture supernatant, indicating that enzyme(s) were responsible for the AFB1 biotransformation. This is the first report on AFB1 transformation by a strain of myxobacteria through enzymatic reaction(s). PMID:21152320

  14. Cytotoxic effects of aflatoxin B1 on human brain microvascular endothelial cells of the blood-brain barrier.

    PubMed

    Qureshi, Humaira; Hamid, Saeed S; Ali, Syed Shayan; Anwar, Javeria; Siddiqui, Anwar Ali; Khan, Naveed Ahmed

    2015-05-01

    Aflatoxins are mycotoxins produced by Aspergillus spp. Although AFB1 is implicated as a carcinogen in hepatocellular carcinoma, brain autopsies in affected areas have revealed its presence in 81% of cases. Given its haematogenous spread, here we determined the cytotoxic effects of AFB1 on primary human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier, human umbilical vein endothelial cells (HUVEC) as well as immortalized epithelial cells of human hepatocellular carcinoma (Huh7). The cell types were exposed to AFB1 (3-32 nM) for 24 h and release of lactate dehydrogenase was measured as cell cytotoxicity marker. Furthermore, DNA was collected from both cell types and DNA adduct formation was determined by immunoblot using anti-AFB1-DNA adduct antibody. At 32 nM, AFB1 killed >85% HBMEC, while controls showed minimal effects (P < .05). Similar concentrations of AFB1 showed 22% cell death of HUVEC, while the same concentration did not kill Huh7. At low concentrations, in other words, 3.2 nM, AFB1 produced DNA adduct formation in HBMEC, while high concentration (32 nM) did not form DNA adducts. For HUVEC, 16 nM and 32 nM exhibited DNA adduct formation. For Huh7, 3.2 nM did not form DNA adducts, while 32 nM exhibited DNA adduct formation. For the first time, we report that AFB1 affected the viability of primary endothelial cells but not immortalized Huh7 cells. Cytotoxicity of brain endothelial cells suggests extra-hepatic complications post-AFB1 exposure.

  15. Grapefruit juice intake does not enhance but rather protects against aflatoxin B1-induced liver DNA damage through a reduction in hepatic CYP3A activity.

    PubMed

    Miyata, Masaaki; Takano, Hiroki; Guo, Lian Q; Nagata, Kiyoshi; Yamazoe, Yasushi

    2004-02-01

    Influence of grapefruit juice intake on aflatoxin B1 (AFB1)-induced liver DNA damage was examined using a Comet assay in F344 rats given 5 mg/kg AFB1 by gavage. Rats allowed free access to grapefruit juice for 5 days prior to AFB1 administration resulted in clearly reduced DNA damage in liver, to 65% of the level in rats that did not receive grapefruit juice. Furthermore, rats treated with grapefruit juice extract (100 mg/kg per os) for 5 days prior to AFB1 treatment also reduced the DNA damage to 74% of the level in rats that did not receive grapefruit juice. No significant differences in the portal blood and liver concentrations of AFB1 were observed between grapefruit juice intake rats and the controls. In an Ames assay with AFB1 using Salmonella typhimurium TA98, lower numbers of revertant colonies were detected with hepatic microsomes prepared from rats administered grapefruit juice, compared with those from control rats. Microsomal testosterone 6beta-hydroxylation was also lower with rats given grapefruit juice than with control rats. Immunoblot analyses showed a significant decrease in hepatic CYP3A content, but not CYP1A and CYP2C content, in microsomes of grapefruit juice-treated rats than in non-treated rats. No significant difference in hepatic glutathione S-transferase (GST) activity and glutathione content was observed in the two groups. GSTA5 protein was not detected in hepatic cytosol of the two groups. In microsomal systems, grapefruit juice extract inhibited AFB1-induced mutagenesis in the presence of a microsomal activation system from livers of humans as well as rats. These results suggest that grapefruit juice intake suppresses AFB1-induced liver DNA damage through inactivation of the metabolic activation potency for AFB1 in rat liver.

  16. Effects of chlorophyll and chlorophyllin on low-dose aflatoxin B(1) pharmacokinetics in human volunteers.

    PubMed

    Jubert, Carole; Mata, John; Bench, Graham; Dashwood, Roderick; Pereira, Cliff; Tracewell, William; Turteltaub, Kenneth; Williams, David; Bailey, George

    2009-12-01

    Chlorophyll (Chla) and chlorophyllin (CHL) were shown previously to reduce carcinogen bioavailability, biomarker damage, and tumorigenicity in trout and rats. These findings were partially extended to humans, where CHL reduced excretion of aflatoxin B(1) (AFB(1))-DNA repair products in Chinese unavoidably exposed to dietary AFB(1). However, neither AFB(1) pharmacokinetics nor Chla effects were examined. We conducted an unblinded crossover study to establish AFB(1) pharmacokinetic parameters among four human volunteers, and to explore possible effects of CHL or Chla cotreatment in three of those volunteers. For protocol 1, fasted subjects received an Institutional Review Board-approved dose of 14C-AFB(1) (30 ng, 5 nCi) by capsule with 100 mL water, followed by normal eating and drinking after 2 hours. Blood and cumulative urine samples were collected over 72 hours, and 14C- AFB(1) equivalents were determined by accelerator mass spectrometry. Protocols 2 and 3 were similar except capsules also contained 150 mg of purified Chla or CHL, respectively. Protocols were repeated thrice for each volunteer. The study revealed rapid human AFB(1) uptake (plasma k(a), 5.05 + or - 1.10 h(-1); T(max), 1.0 hour) and urinary elimination (95% complete by 24 hours) kinetics. Chla and CHL treatment each significantly impeded AFB(1) absorption and reduced Cmax and AUCs (plasma and urine) in one or more subjects. These initial results provide AFB(1) pharmacokinetic parameters previously unavailable for humans, and suggest that Chla or CHL co-consumption may limit the bioavailability of ingested aflatoxin in humans, as they do in animal models.

  17. Homogeneous electrochemical immunoassay of aflatoxin B1 in foodstuff using proximity-hybridization-induced omega-like DNA junctions and exonuclease III-triggered isothermal cycling signal amplification.

    PubMed

    Tang, Juan; Huang, Yapei; Liu, Huiqiong; Zhang, Cengceng; Tang, Dianping

    2016-12-01

    A new homogeneous electrochemical immunosensing platform was designed for sensitive detection of aflatoxin B1 (AFB1) in foodstuff. The system consisted of anti-AFB1 antibody labeled DNA1 (Ab-DNA1), AFB1-bovine serum albumin (BSA)-conjugated DNA2 (AFB1-DNA2), and methylene blue functionalized hairpin DNA. Owing to a specific antigen-antibody reaction between anti-AFB1 and AFB1-BSA, the immunocomplex formed assisted the proximity hybridization of DNA1 with DNA2, thus resulting in the formation of an omega-like DNA junction. Thereafter, the junction opened the hairpin DNA to construct a new double-stranded DNA, which could be readily cleaved by exonuclease III to release the omega-like DNA junction and methylene blue. The dissociated DNA junction could repeatedly hybridize with residual hairpin DNA molecules with exonuclease III-based isothermal cycling amplification, thereby releasing numerous free methylene blue molecules into the detection solution. The as-produced free methylene blue molecules could be captured by a negatively charged indium tin oxide electrode, each of which could produce an electronic signal within the applied potentials. On introduction of target AFB1, the analyte competed with AFB1-DNA2 for the conjugated anti-AFB1 on the Ab-DNA1, subsequently decreasing the amount of omega-like DNA junctions formed, hence causing methylene blue labeled hairpin DNA to move far away from the electrode surface. Under optimal conditions the detectable electrochemical signal decreased with increasing amount of target AFB1 in a dynamic working range of 0.01-30 ng mL(-1) with a detection limit of 4.8 pg mL(-1). In addition, the precision and reproducibility of this system were acceptable. Finally, the method was further evaluated for analysis of naturally contaminated or AFB1-spiked peanut samples, giving results that matched well with those obtained with a commercial AFB1 ELISA kit.

  18. Effect of dietary resveratrol in ameliorating aflatoxin B1-induced changes in broiler birds.

    PubMed

    Sridhar, M; Suganthi, R U; Thammiaha, V

    2015-12-01

    Consumption of aflatoxin B1 (AFB1) contaminated feed by poultry affects the health of broiler birds causing severe economic losses. The use of phytochemicals is a safe, effective, alternative and practical approach to combat the toxic effect of AF in broilers. Resveratrol, a polyphenol derived from red grapes, berries and peanuts, exerts anti-inflammatory, antioxidant and immunomodulatory effects. Our study was aimed at evaluating the possible protective effects of resveratrol against the adverse effects of AFB1 in broiler birds. A feeding trial of 42 days of duration was undertaken in a completely randomized design with five dietary treatments: G1-AFB1(1.0 ppm); G2-CTR (basal diet alone); G3-AFB1(1.0 ppm)+Resv 0.5%; G4-AFB1(1.0 ppm)+Resv 1%; and G5-Resv 1%. Gain in body weight (BWG) and feed intake (FI) was observed to be highest (p < 0.05) in the AFB1 birds followed by the control group. Feed conversion ratio was lowest in G2-CTR birds and failed to record any significant variation (p > 0.05) between groups as well as within groups. Birds fed resveratrol at both 0.5% and 1.0% levels in combination with AFB1 as well as alone along with basal diet had lower BWG and FI between the fourth and fifth week and also at the fifth week (p < 0.05). No variation (p > 0.05) was obtained in the FCR of AFB1 and resveratrol group of broiler birds. AFB1 feeding significantly increased the activities of aspartate-(AST) and alanine-(ALT) amino transferase, superoxide dismutase (SOD) and catalase (CAT) activities (p < 0.05) but lowered glucose, cholesterol and triglyceride levels in serum. Supplementation of resveratrol helped in increasing the activities of the oxidative enzymes and in improving the plasma total antioxidant capacity (TAOC) and total protein (TP) significantly (p < 0.05) and protein values. The livers of AFB1 group showed degeneration of hepatocytes, bile duct hyperplasia and microgranuloma formation. In resveratrol supplemented birds, the severity and degree of the

  19. [The aflatoxins and liver cancer in Guangxi, China].

    PubMed

    Yu, S Z

    1992-05-01

    The AFB1 intake and the AFM1 excretion of 81 households in 10 villages, Guanxi were investigated using the ELISA method. The results showed that there was positive correlation between PLC mortality and AFB1 intake from corn and peanut oil, but not from rice. The results of stepwise regression showed that main factors were AFB1 intake of males, AFM1 excretion of females and consumption of corn. The results showed that aflatoxins were correlated with mortality rates of liver cancer. Further investigation needs to be carried out in case-control and cohort studies.

  20. Effects of donor fibroblast cell type and transferred cloned embryo number on the efficiency of pig cloning.

    PubMed

    Li, Zicong; Shi, Junsong; Liu, Dewu; Zhou, Rong; Zeng, Haiyu; Zhou, Xiu; Mai, Ranbiao; Zeng, Shaofen; Luo, Lvhua; Yu, Wanxian; Zhang, Shouquan; Wu, Zhenfang

    2013-02-01

    Currently, cloning efficiency in pigs is very low. Donor cell type and number of cloned embryos transferred to an individual surrogate are two major factors that affect the successful rate of somatic cell nuclear transfer (SCNT) in pigs. This study aimed to compare the influence of different donor fibroblast cell types and different transferred embryo numbers on recipients' pregnancy rate and delivery rate, the average number of total clones born, clones born alive and clones born healthy per litter, and the birth rate of healthy clones (=total number of healthy cloned piglets born /total number of transferred cloned embryos). Three types of donor fibroblasts were tested in large-scale production of cloned pigs, including fetal fibroblasts (FFBs) from four genetically similar Western swine breeds of Pietrain (P), Duroc (D), Landrace (L), and Yorkshire (Y), which are referred to as P,D,LY-FFBs, adult fibroblasts (AFBs) from the same four breeds, which are designated P,D,L,Y-AFBs, and AFBs from a Chinese pig breed of Laiwu (LW), which is referred to as LW-AFBs. Within each donor fibroblast cell type group, five transferred cloned embryo number groups were tested. In each embryo number group, 150-199, 200-249, 250-299, 300-349, or 350-450 cloned embryos were transferred to each individual recipient sow. For the entire experiment, 92,005 cloned embryos were generated from nearly 115,000 matured oocytes and transferred to 328 recipients; in total, 488 cloned piglets were produced. The results showed that the mean clones born healthy per litter resulted from transfer of embryos cloned from LW-AFBs (2.53 ± 0.34) was similar with that associated with P,D,L,Y-FFBs (2.72 ± 0.29), but was significantly higher than that resulted from P,D,L,Y-AFBs (1.47 ± 0.18). Use of LW-AFBs as donor cells for SCNT resulted in a significantly higher pregnancy rate (72.00% vs. 59.30% and 48.11%) and delivery rate (60.00% vs. 45.93% and 35.85%) for cloned embryo recipients, and a

  1. Ellagic acid peracetate is superior to ellagic acid in the prevention of genotoxicity due to aflatoxin B1 in bone marrow and lung cells.

    PubMed

    Kumar, Ajit; Tyagi, Yogesh K; Ponnan, Prija; Rohil, Vishwajeet; Prasad, Ashok K; Dwarkanath, Bilekere S; Parmar, Virinder S; Raj, Hanumantharao G

    2007-01-01

    Earlier observations carried out in our laboratory highlighted the mode of action of acetoxy 4-methylcoumarins and quercetin pentaacetate in preventing the genotoxicity of aflatoxin B1 (AFB1). We have extended the observation to an acetoxy biscoumarin i.e. ellagic acid peracetate (EAPA), which unlike ellagic acid (EA) has demonstrated time-dependent inhibition of liver microsomes catalysed AFB1-epoxidation as measured by AFB1 binding to DNA. EAPA was more potent than EA in preventing bone marrow and lung cells from AFB1-induced genotoxicity. EAPA was acted upon by microsomal acetoxy drug:protein transacetylase (TAase) leading to modulation of the catalytic activity of certain functional proteins (cytochrome P450, NADPH cytochrome c reductase and glutathione S-transferase), possibly by way of protein acetylation.

  2. Differential inhibition of aflatoxin B1 oxidation by gestodene action on human liver microsomes.

    PubMed

    Kim, B R; Oh, H S; Kim, D H

    1997-11-01

    Human cytochrome P450 (P450) 3A is known to be involved in the formation of both aflatoxin B1-exo-8,9-epoxide (exo-epoxidation) and aflatoxin Q1 (3 alpha-hydroxylation). Gestodene, a known inactivator of P450 3A4, inhibited the formation of AFB1 metabolites in a variety of ways depending on the incubation condition. Preincubation of gestodene with human liver microsomes prior to the addition of AFB1 inhibited both exo-epoxidation and 3 alpha-hydroxylation whereas simultaneous incubation of gestodene with AFB1 only inhibited 3 alpha-hydroxylation. These results suggest that two independent substrate binding sites exist in P450 3A4, and AFB1 binds to both of the binding sites. Gestodene selectively binds to one of the binding sites leading to the formation of AFQ1, whereas it does not affect the formation of exo-epoxide via the other binding site.

  3. Impact of casing damaging on aflatoxin B1 concentration during the ripening of dry-fermented meat sausages.

    PubMed

    Pleadin, Jelka; Kovačević, Dragan; Perković, Irena

    2015-01-01

    The aim of this article is to investigate the impact of casing damaging on the formation of aflatoxin B1 (AFB1) during the ripening of dry-fermented meat sausages. The level of AFB1 contamination was determined in 24 samples using the ELISA immunoassay throughout a six-month production period. While with intact casing samples no contamination was observed throughout the whole production process, in damaged casing samples AFB1 was detected in the ripening end-stages in the range of 1.62-4.49 μg/kg. The results showed that casing damaging occurring during long-term ripening of dry-fermented sausages can cause AFB1 contamination, possibly arising on the grounds of diffusion of this mycotoxin from the product surface to its interior.

  4. How does airway exposure of aflatoxin B1 affect serum albumin adduct concentrations? Evidence based on epidemiological study and animal experimentation.

    PubMed

    Mo, Xianwei; Lai, Hao; Yang, Yang; Xiao, Jun; He, Ke; Liu, Chao; Chen, Jiansi; Lin, Yuan

    2014-08-01

    Aflatoxin B1 (AFB1) airway inhalation represents an additional route of exposure to this toxin. However, the association between AFB1 inhalation and serum AFB1 albumin adducts remains unclear. The aim of this study was to explore the association between airway exposure to AFB1 and serum AFB1 albumin adduct concentrations via an epidemiological study, as well as in an AFB1 airway exposure animal model. Our epidemiological study was conducted in a sugar factory in the Guangxi Autonomous Region of China. In order to examine fungal contamination, air samples were obtained in the workshop and areas outside the workshop, such as the office and nearby store. Dust samples were also collected from the bagasse warehouse and presser workshop, and were analyzed using an indirect competitive enzyme-linked immunosorbent assay (ELISA). Additionally, blood samples were collected from a total of 121 workshop workers, and a control group (n = 80) was comprised of workers who undertook administrative tasks or other work outside the workshop. The animal experiment was conducted in the laboratory animal center of Guangxi Medical University, where a total of 60 adult male rabbits were involved in this study. By intubation, AFB1 was administered in three groups of rabbits daily, at dose rates of 0.075, 0.05 and 0.025 mg/kg/day for a period of 7 days. Blood samples were collected on day 1, day 3, day 7 and day 21, and the measurements of the AFB1 albumin adducts in the serum were performed by a double antibody sandwich ELISA. The epidemiological study showed that serum albumin adducts were detected in 67 workshop workers (55.37%), and the values ranged 6.4 pg/mg albumin to 212 pg/mg albumin (mean value: 51 ± 4.62 pg/mg albumin). In contrast, serum albumin adducts were detected in only 7 control group participants, with the values ranging from 9 pg AFB1/mg albumin to 59 pg/mg albumin (mean value: 20 ± 13.72 pg/mg albumin). The animal experiment revealed that the rabbits had detectable

  5. Chemopreventive effect of cactus Opuntia ficus indica on oxidative stress and genotoxicity of aflatoxin B1

    PubMed Central

    2011-01-01

    Background Aflatoxin B1 (AFB1) is potent hepatotoxic and hepatocarcinogenic agent. In aflatoxicosis, oxidative stress is a common mechanism contributing to initiation and progression of hepatic damage. The aim of this work was to evaluate the hepatoprotective effect of cactus cladode extract (CCE) on aflatoxin B1-induced liver damage in mice by measuring malondialdehyde (MDA) level, the protein carbonyls generation and the heat shock proteins Hsp 70 and Hsp 27 expressions in liver. We also looked for an eventual protective effect against AFB1-induced genotoxicity as determined by chromosome aberrations test, SOS Chromotest and DNA fragmentation assay. We further evaluated the modulation of p53, bax and bcl2 protein expressions in liver. Methods Adult, healthy balbC (20-25 g) male mice were pre-treated by intraperitonial administration of CCE (50 mg/Kg.b.w) for 2 weeks. Control animals were treated 3 days a week for 4 weeks by intraperitonial administration of 250 μg/Kg.b.w AFB1. Animals treated by AFB1 and CCE were divided into two groups: the first group was administrated CCE 2 hours before each treatment with AFB1 3 days a week for 4 weeks. The second group was administrated without pre-treatment with CCE but this extract was administrated 24 hours after each treatment with AFB1 3 days a week for 4 weeks. Results Our results clearly showed that AFB1 induced significant alterations in oxidative stress markers. In addition, it has a genotoxic potential and it increased the expression of pro apoptotic proteins p53 and bax and decreased the expression of bcl2. The treatment of CCE before or after treatment with AFB1, showed (i) a total reduction of AFB1 induced oxidative damage markers, (ii) an anti-genotoxic effect resulting in an efficient prevention of chromosomal aberrations and DNA fragmentation compared to the group treated with AFB1 alone (iii) restriction of the effect of AFB1 by differential modulation of the expression of p53 which decreased as well as its

  6. Removal of aflatoxin B1-DNA adducts and in vitro transformation in mouse embryo fibroblasts C3H/10T1 1/2

    SciTech Connect

    Amstad, P.A.; Wang, T.V.; Cerutti, P.A.

    1983-01-01

    The mechanism of in vitro transformation of the mouse embryo fibroblast C3H/10T 1/2 clone 8 by aflatoxin B1 (AFB1) was studied in confluent holding (CH) experiments. Confluent cultures of C3H/10T 1/2 cells were treated with AFB1 for 16 hours, and the DNA adduct composition and concentration were determined by chromatographic procedures after 0, 8, 16, and 40 hours of CH when the cells were replated at low density for the expression of their colony-forming ability and the formation of transformed foci. Total adduct concentration and the concentration of the major primary adduct 2,3-dihydro-2-(N7-guanyl)-3-hydroxyaflatoxin B1 (AFB1-N7-Gua) decreased continuously during CH due to spontaneous decomposition and probably also due to enzymatic repair processes. In contrast, the more chemically stable secondary product 2,3-dihydro-2-(N5-formyl-2',5',6'-triamino-4'-oxo-N5-pyrimidyl)-3-hydroxyaflatoxin B1 (AFB1-triamino-Py) accumulated in the DNA and reached its maximum concentration after 16 hours of CH. While the loss of total AFB1-DNA adducts during CH was reflected in recovery of viability, the potential to form transformed foci reached a maximum after 16 hours of CH and then decreased with continued CH below the initial value. Therefore, no simple relationship exists between the concentration of the total adducts AFB1-N7-Gua and AFB1-triamino-Py at the time of release from CH and the potential to form transformed foci. However, DNA lesions or abnormal DNA configurations formed during CH as a consequence of the cellular processing of AFB1-DNA adducts may play a role in the transformation process.

  7. Aflatoxin binders II: reduction of aflatoxin M1 in milk by sequestering agents of cows consuming aflatoxin in feed.

    PubMed

    Diaz, Duarte E; Hagler, Winston M; Blackwelder, John T; Eve, Julie A; Hopkins, Brinton A; Anderson, Kevin L; Jones, Frank T; Whitlow, Lon W

    2004-02-01

    Sequestering agents bind dietary aflatoxin B1 (AFB1) and reduce absorption from an animal's gastrointestinal tract. As a result, they protect an animal from the toxic effects of AFB1 and reduce transfer of the metabolite, aflatoxin M1 (AFM1), into milk. Three experiments, using late-lactation Holstein cows fed AFB1-contaminated feed, were conducted to evaluate several potential sequestering agents for their abilities to prevent or reduce the transmission of AFM1 into milk. Six agents previously tested in our laboratory for AFB1 binding in vitro were evaluated in these experiments. These were: SA-20, an activated carbon (AC-A); Astra-Ben-20, a sodium bentonite (AB-20); MTB-100, an esterified glucomannan (MTB-100); Red Crown, a calcium bentonite (RC); Flow Guard, a sodium bentonite (FG); and Mycrosorb, a sodium bentonite (MS). Five of the six sequestering agents significantly (P < 0.01) reduced AFM1 contamination of milk (AB-20, 61%; FG, 65%; MS, 50%; MTB-100, 59%; and RC, 31%); whereas, AC-A, activated carbon, had no effect on AFM1 transmission at 0.25% of feed. By the first milking (1 day after cows consumed contaminated feed), AFM1 appeared in milk, then reached maximum levels after three days, and was absent from milk within four days after AFB1 was removed from the feed. Sodium bentonites at 1.2% of feed showed good potential as AFB1 binders; MTB-100, a yeast cell wall product, was equally effective at 0.05% in feed. Potential AFB1 binding agents should be evaluated experimentally to demonstrate efficacy. Our data show that sequestering agents can reduce AFM1 in milk of cows fed AFB1-contaminated feed.

  8. Protective Efficacy of Alpha-lipoic Acid against AflatoxinB1-induced Oxidative Damage in the Liver

    PubMed Central

    Li, Y.; Ma, Q. G.; Zhao, L. H.; Guo, Y. Q.; Duan, G. X.; Zhang, J. Y.; Ji, C.

    2014-01-01

    Alpha-lipoic acid (α-LA) is not only involved in energy metabolism, but is also a powerful antioxidant that can protect against hepatic oxidative stress induced by some drugs, toxins, or under various physiological and pathophysiological conditions. Here, we investigated the effect of α-LA against liver oxidative damage in broilers exposed to aflatoxin B1 (AFB1). Birds were randomly divided into four groups and assigned different diets: basal diet, 300 mg/kg α-LA supplementation in basal diet, diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in diet containing 74 μg/kg AFB1, for 3 weeks. The results revealed that the addition of 300 mg/kg α-LA protected against the liver function damage of broilers induced by chronic low dose of AFB1 as estimated by a significant (p<0.05) change in levels of plasma total protein, albumin, alkaline phosphatase and the activities of liver glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase. The histopathological analysis also showed that liver tissues were injured in the AFB1 diet, but this effect was alleviated by the addition of 300 mg/kg α-LA. Additionally, AFB1 induced a profound elevation of oxidative stress in birds, as indicated by an increase in malondialdehyde level, a decrease in glutathione peroxidase activity and a depletion of the glutathione content in the liver. All of these negative effects were inhibited by treatment with α-LA. Our results suggest that the inhibition of AFB1-induced excess production of lipid peroxides and the maintenance of intracellular antioxidant status may play important roles in the protective effects of α-LA against AFB1-induced oxidative damage in the liver. PMID:25050030

  9. Antigenotoxic Effect of Piperine in Broiler Chickens Intoxicated with Aflatoxin B1

    PubMed Central

    da Silva Cardoso, Verônica; Vermelho, Alane Beatriz; Ribeiro de Lima, Cristina Amorim; Mendes de Oliveira, Jéssica; Freire de Lima, Marco Edilson; Pinto da Silva, Lúcia Helena; Direito, Glória Maria; Miranda Danelli, Maria das Graças

    2016-01-01

    Piperine is an abundant amide extracted from black pepper seeds which has been shown to have protective effects against cytotoxic and genotoxic carcinogenesis induced by certain chemical carcinogens and aflatoxin B1 (AFB1) in vitro. The aim of this work was to study, in vivo, the antigenotoxic potential of feed-added piperine on broiler chickens experimentally intoxicated with AFB1, using micronucleus and comet assays. The antigenotoxicity assessment of 9-day-old chicks was performed on a total of 60 chickens divided into four groups of 15 broilers each: (C) control, (P) 60 mg·piperine kg−1 feed, (A) 0.5 mg·AFB1·kg−1 body weight, (daily by oral route), and (P + A) co-treatment with piperine and AFB1. The experiment was conducted for 26 days. Chicks intoxicated with AFB1 showed significant genotoxic effects in the first 24 h post intoxication, and the effects remained in the other periods analyzed (48, 72, and 96 h and 26 days of treatment). The DNA damage in peripheral blood cells, the number of erythrocytes with micronuclei, and polychromatic-to-normochromatic erythrocyte ratio were significantly reduced or absent in the piperine/AFB1 group. No significant differences were observed between the group piperine/AFB1 and the control and piperine-alone groups. The addition 60 mg·kg−1 of piperine to the diet of the broiler chicks was safe, promoting beneficial effects in poultry health with respect to the toxic effects 0.5 mg·AFB1·kg−1 body weight. PMID:27809242

  10. Immunotoxicity of aflatoxin B1: Impairment of the cell-mediated response to vaccine antigen and modulation of cytokine expression

    SciTech Connect

    Meissonnier, Guylaine M.; Pinton, Philippe; Laffitte, Joelle; Cossalter, Anne-Marie; Gong, Yun Yun; Wild, Christopher P.; Bertin, Gerard; Galtier, Pierre; Oswald, Isabelle P.

    2008-09-01

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus or A. parasiticus, is a frequent contaminant of food and feed. This toxin is hepatotoxic and immunotoxic. The present study analyzed in pigs the influence of AFB1 on humoral and cellular responses, and investigated whether the immunomodulation observed is produced through interference with cytokine expression. For 28 days, pigs were fed a control diet or a diet contaminated with 385, 867 or 1807 {mu}g pure AFB1/kg feed. At days 4 and 15, pigs were vaccinated with ovalbumin. AFB1 exposure, confirmed by an observed dose-response in blood aflatoxin-albumin adduct, had no major effect on humoral immunity as measured by plasma concentrations of total IgA, IgG and IgM and of anti-ovalbumin IgG. Toxin exposure did not impair the mitogenic response of lymphocytes but delayed and decreased their specific proliferation in response to the vaccine antigen, suggesting impaired lymphocyte activation in pigs exposed to AFB1. The expression level of pro-inflammatory (TNF-{alpha}, IL-1{beta}, IL-6, IFN-{gamma}) and regulatory (IL-10) cytokines was assessed by real-time PCR in spleen. A significant up-regulation of all 5 cytokines was observed in spleen from pigs exposed to the highest dose of AFB1. In pigs exposed to the medium dose, IL-6 expression was increased and a trend towards increased IFN-{gamma} and IL-10 was observed. In addition we demonstrate that IL-6 impaired in vitro the antigenic- but not the mitogenic-induced proliferation of lymphocytes from control pigs vaccinated with ovalbumin. These results indicate that AFB1 dietary exposure decreases cell-mediated immunity while inducing an inflammatory response. These impairments in the immune response could participate in failure of vaccination protocols and increased susceptibility to infections described in pigs exposed to AFB1.

  11. Effects of Aflatoxin B1 on T-Cell Subsets and mRNA Expression of Cytokines in the Intestine of Broilers

    PubMed Central

    Jiang, Min; Peng, Xi; Fang, Jing; Cui, Hengmin; Yu, Zhengqiang; Chen, Zhengli

    2015-01-01

    This study was conducted to investigate the effects of aflatoxin B1 (AFB1) on T-cell subsets and mRNA expression of cytokines in the small intestine of broilers. One hundred and fifty-six one-day-old healthy Cobb broilers were randomly divided into control group (0 mg/kg AFB1) and AFB1 group (0.6 mg/kg AFB1) with three replicates per group and 26 birds per replicate for 21 days, respectively. At 7, 14, and 21 days of age, the duodenum, jejunum and ileum were sampled for analyzing T cell subsets (CD3+, CD3+CD4+ and CD3+CD8+) by flow cytometry as well as IL-2, IL-4, IL-6, IL-10, IL-17, IFN-γ and TNF-α mRNA expression by qRT-PCR. The percentages of T-cells in the intra-epithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) of duodenum, jejunum and ileum in the AFB1 group showed a decreased tendency in comparison to the control group. The mRNA expression of cytokines in the three intestinal segments in the AFB1 group presented a general decline compared with the control groups. Our data demonstrated that 0.6 mg/kg AFB1 in the broilers diet could reduce the percentages of T-cell subsets and the expression level of cytokine mRNA in the small intestine, implying that the immune function of the intestinal mucosa might be affected. The reduction of cytokines mRNA expression may be closely associated with the decreased proportions of T cells subsets induced by AFB1. PMID:25826527

  12. Effects of dietary protein concentration on performance and nutrient digestibility in Pekin ducks during aflatoxicosis.

    PubMed

    Chen, X; Murdoch, R; Zhang, Q; Shafer, D J; Applegate, T J

    2016-04-01

    A 14-d study was conducted to determine the impact of dietary crude protein concentration on performance, serum biochemistry, and nutrient digestive functions in Pekin ducklings during aflatoxicosis. A total of 144 male Pekin ducklings were randomly allotted to 4 dietary treatments arranged in a 2×2 factorial with 2 crude protein (CP) (20 and 24% on an analyzed basis) with or without 0.2 mg/kg aflatoxin B1 (AFB1) (0.21 mg/kg analyzed). The AFB1 reduced BW gain, feed intake, and breast muscle weight by 33 to 43% (P<0.0001). Serum concentration of protein, glucose, and Ca were also decreased by AFB1 (P≤0.0015), while pancreatic activities of amylase and lipase were increased by AFB1 (P<0.005). Apparent N digestibility was not affected by dietary treatment, whereas apparent ileal digestible energy was reduced 7.6% by AFB1 (P=0.0003). Higher dietary CP improved BW gain, gain:feed ratio, and breast muscle weight (P≤0.021), and tended to improve feed intake (P=0.094), but did not improve serum measures, digestive enzyme activity, or nutrient digestibility. No statistical interaction of AFB1 by CP was observed for any measures. Results from the current study suggest that AFB1 at low concentration can significantly impair performance of Pekin ducklings primarily through inhibited feed intake, as well as influence nutrient digestion processes (jejunum morphology, digestive enzyme activity, and apparent energy digestibility). Higher dietary CP can improve growth performance of ducklings regardless of AF exposure, but did not interact with dietary AFB1 on performance, serum biochemistry, or nutrient digestion in Pekin ducklings from hatch to 14 d.

  13. Chemiluminescence and fluorescence spectrum methods for determination of Aflatoxin B1 mediated by FCLA + BSA

    NASA Astrophysics Data System (ADS)

    Chen, WenLi; Xing, Da

    2005-04-01

    BSA (Bovine Serum Albumin) can enlarge the CL intensity of FCLA(3,7-dihydro-6-{4-{2-(N'-(5-fluoresceinyl) thioureido)ethoxy}phenyl}-2-methylimi-dazo{1,2-a}pyrazin-3-one dosium salt) to 763%. This report presents novel methods for determination of Aflatoxin B1 (AfB1) mediated by FCLA+BSA. The concentration of AFB1 showed an obvious positive correlation with the chemiluminescence (CL) intensity mediated by FCLA+BSA, correlative coefficient R@0.94. This method could measure accurately ng/ml of AfB1 concentration. 365nm as excitated wavelength, 440nm and 520nm-two fluorescence peaks of FCLA+BSA+AfB1 were found. The fluorescence intensity of peak at 440nm showed an obvious positive correlation with the concentration of AFB1, R@0.97; the fluorescence intensity of peak at 520nm showed a positive correlation with the concentration of AFB1, R@0.90. Comparing the peak of FCLA, FCLA+BSA and FCLA+BSA+AfB1 had a 6nm Einstein shift (red shift). The study suggested that CL and fluorescence spectrum methods mediated by FCLA+BSA might be applicable to the determination of AfB1 concentration.

  14. FRET-based aptamer biosensor for selective and sensitive detection of aflatoxin B1 in peanut and rice.

    PubMed

    Sabet, Fereshte Sadat; Hosseini, Morteza; Khabbaz, Hossein; Dadmehr, Mehdi; Ganjali, Mohammad Reza

    2017-04-01

    Aflatoxins are potential food pollutants produced by fungi. Among them, Aflatoxin B1 (AFB1) is the most toxic. Therefore, a great deal of concern is associated with AFB1 toxicity. In this work, utilizing a FRET-based method, we have developed a nanobiosensor for detection of AFB1 in agricultural foods. Aptamer-conjugated Quantum dots (QDs) are adsorbed to Au nanoparticles (AuNPs) due to interaction of aptamers with AuNPs leading to quenching effect on QDs fluorescence. Upon the addition of AFB1, the specific aptamers are attracted to AFB1, getting distance from AuNPs which result in fluorescence recovery. Under optimized conditions the detection limit of proposed nanobiosensor was 3.4nM with linear range of 10-400nM. Selectivity test demonstrates that the nanobiosensor could be a promising tool for specific evaluation of food stuff. This method was successfully applied for the analysis of AFB1 in rice and peanut samples.

  15. Hepatic Transcriptome Responses of Domesticated and Wild Turkey Embryos to Aflatoxin B1

    PubMed Central

    Monson, Melissa S.; Cardona, Carol J.; Coulombe, Roger A.; Reed, Kent M.

    2016-01-01

    The mycotoxin, aflatoxin B1 (AFB1) is a hepatotoxic, immunotoxic, and mutagenic contaminant of food and animal feeds. In poultry, AFB1 can be maternally transferred to embryonated eggs, affecting development, viability and performance after hatch. Domesticated turkeys (Meleagris gallopavo) are especially sensitive to aflatoxicosis, while Eastern wild turkeys (M. g. silvestris) are likely more resistant. In ovo exposure provided a controlled AFB1 challenge and comparison of domesticated and wild turkeys. Gene expression responses to AFB1 in the embryonic hepatic transcriptome were examined using RNA-sequencing (RNA-seq). Eggs were injected with AFB1 (1 μg) or sham control and dissected for liver tissue after 1 day or 5 days of exposure. Libraries from domesticated turkey (n = 24) and wild turkey (n = 15) produced 89.2 Gb of sequence. Approximately 670 M reads were mapped to a turkey gene set. Differential expression analysis identified 1535 significant genes with |log2 fold change| ≥ 1.0 in at least one pair-wise comparison. AFB1 effects were dependent on exposure time and turkey type, occurred more rapidly in domesticated turkeys, and led to notable up-regulation in cell cycle regulators, NRF2-mediated response genes and coagulation factors. Further investigation of NRF2-response genes may identify targets to improve poultry resistance. PMID:26751476

  16. In vitro evaluation of the capacity of zeolite and bentonite to adsorb aflatoxin B1 in simulated gastrointestinal fluids.

    PubMed

    Thieu, N Q; Pettersson, H

    2008-09-01

    Anin vitro study using single concentration and isotherm adsorption was carried out to evaluate the capacity of Vietnamese produced zeolite and bentonite to adsorb aflatoxin B1 (AFB1) in simulated gastrointestinal fluids (SGFs), and a commercial sorbent hydrated sodium calcium aluminosilicate (HSCAS) was used as reference. In this study, AFB1 solution was mixed with sorbents (0.3, 0.4 and 0.5% w/v) in SGFs at pH 3 and pH 7 and shaken for 8 h, centrifuged and the supernatant measured by Vicam fluorometer. Adsorption of AFB1 onto zeolite and bentonite varied according to the pH of SGFs and was lower than HSCAS. Linearity between the increased amount of AFB1 adsorbed on sorbents and the decrease of sorbent concentration was observed for bentonite and HSCAS, except for zeolite in SGFs at pH 7. The observed maximum amounts of AFB1 adsorbed on bentonite and HSCAS were 1.54 and 1.56 mg/g, respectively. The adsorption capacities of bentonite and HSCAS for AFB1 were 12.7 and 13.1 mg/g, respectively, from fitting the data to the Freundlich isotherm equation. Improvement in processing and purification for bentonite is needed to enhance the surface area, which would probably result in better adsorptive capacity for this sorbent.

  17. The antioxidant effects of vitamin A, C, and E on aflatoxin B1-induced oxidative stress in human lymphocytes.

    PubMed

    Alpsoy, L; Yildirim, A; Agar, G

    2009-03-01

    The aim of this study was to investigate the possible protective role of vitamin A, C, and E on aflatoxin B(1)-induced in human lymphocytes using biochemical approaches. The control group received dimethyl sulfoxide, the second group of cultures were administered aflatoxin B(1) (AFB(1)) at a dose of 5 muM. The other group of cultures were treated with AFB(1)+vitamin A (0.5 and 1.0 and 1.5 microM) and AFB(1)+vitamin C (25, 50, and 100 microM) and AFB(1)+vitamin E (40, 100, and 200 microM). The results of this experiment show that AFB(1) significantly decreased the level of GSH and the activities of superoxide dismutase and GPx and increased level of malondialdehyde. Simultaneous supplementation with vitamin A, C, and E restored these parameters to that of normal range. In conclusion, vitamin A, C, and E exhibited protective effects in human lymphocytes by inhibiting AFB(1)-induced ROS generation.

  18. Comparative Hepatotoxicity of Aflatoxin B1 among Workers Exposed to Different Organic Dust with Emphasis on Polymorphism Role of Glutathione S-Transferase Gene

    PubMed Central

    Saad-Hussein, Amal; Shahy, Eman M.; Shaheen, Weam; Taha, Mona M.; Mahdy-Abdallah, Heba; Ibrahim, Khadiga S.; Hafez, Salwa F.; Fadl, Nevein N.; El-Shamy, Karima A.

    2016-01-01

    AIM: The study aimed to investigate effects of organic dust exposure from different sources on aflatoxin B1-albumin adducts (AFB1/Alb), and role of glutathione S-transferase (GST) gene polymorphism in hepatotoxicity of (AFB1) among exposed workers. MATERIAL AND METHODS: Liver enzymes, AFB1/Alb, and GST polymorphism were estimated in 132 wheat flour dust and 87 woods sawmill workers, and 156 controls. RESULTS: Results revealed that AFB1/Alb and liver enzymes were significantly elevated in exposed workers compared to controls, and were significantly higher in sawmill workers compared to flour workers. AFB1/Alb in flour and sawmill workers with GSTT1 and GSTM1&GSTT1 null genotypes were significantly higher than controls, and in sawmill workers with GSTM1&GSTT1 null than flour workers. Liver enzymes (ALT and AST) in sawmill workers were significantly higher than flour workers and controls in all GST polymorphism; except in GSTT1 polymorphism, where these enzymes were significantly higher in the two exposed groups than controls. CONCLUSIONS: In conclusion, organic dust exposure may cause elevation in AFB1/Alb and liver enzymes of exposed workers, and GST gene polymorphism plays an important role in susceptibility to hepatic parenchymal cell injury; except in workers with GSTT1&GSTM1 null genotype, gene susceptibility seemed to have little role and the main role was for environmental exposures. PMID:27335608

  19. Subchronic mycotoxicoses in rats. Histopathological changes and modulation of the sphinganine to sphingosine (Sa/So) ratio imbalance induced by Fusarium verticillioides culture material, due to the coexistence of aflatoxin B1 in the diet.

    PubMed

    Theumer, M G; López, A G; Aoki, M P; Cánepa, M C; Rubinstein, H R

    2008-03-01

    Mycotoxicoses are diseases caused by consumption of diets contaminated with mycotoxins, a special class of fungal secondary metabolites. Fumonisin B1 (FB1) and aflatoxin B1 (AFB1), the main toxins synthesized by toxicogenic stocks of Fusarium spp. and Aspergillus spp., respectively, can coexist in grains and in its by-products. We investigated a probable synergism of a fumonisins-containing Fusarium verticillioides culture material and AFB1 in the induction of hepatocyte apoptosis in rats subchronically fed on a mixture of them. Furthermore, the possibility of modifications in the fumonisins-induced Sa/So ratio imbalance in tissues and urine from rats poisoned with this mycotoxin, due to the presence of AFB1 in the diet, was evaluated. The co-exposure to fumonisins and AFB1 produced a higher liver toxicity, with respect to their individual administration, inducing apoptosis and mitotic hepatocytes. There was an inversion of the typical Sa/So ratio in rats fed on the culture material as well as in those subjected to a diet co-contamined with fumonisins and AFB1. Moreover, the later had a synergistic effect in the induction of Sa/So variations in kidneys. Therefore, the mixture of fumonisins and AFB1 induced toxic responses which could not be considered a sum of the effects caused individually by these mycotoxins.

  20. Aflatoxin B1 Suppressed T-Cell Response to Anti-pig-CD3 Monoclonal Antibody Stimulation in Primary Porcine Splenocytes: A Role for the Extracellular Regulated Protein Kinase (ERK1/2) MAPK Signaling Pathway.

    PubMed

    Hao, Shu; Pan, Shengchi; Hu, Junfa; Qian, Gang; Gan, Fang; Huang, Kehe

    2015-07-08

    The aim of the present study is to investigate whether aflatoxin B1 (AFB1)-induced immunotoxicity is associated with oxidative stress and the expression of extracellular regulated protein kinases (ERK) 1/2. The primary splenocytes isolated from healthy pigs were activated and proliferated by anti-pig-CD3 monoclonal antibodies (mAb) in the present experiment, which is an antigen-specific stimulant. Results indicated that cell proliferation and interleukin-2 (IL-2) production were significantly suppressed by AFB1 from 4 to 8 μg/mL in a dose-dependent manner compared to the control group. Furthermore, AFB1 significantly increased malondialdehyde (MDA) levels, decreased reduced glutathione (GSH) and total superoxide dismutase levels, and up-regulated p-ERK1/2 expression in the activated splenocytes. N-Acetyl-l-cysteine blocked anti-CD3-induced T-cell suppression by AFB1 through increasing intracellular concentrations of GSH levels, decreasing MDA levels, and down-regulated p-ERK1/2 expression, respectively. Inhibition of the ERK1/2 expression by ERK-specific iRNA attenuated the decrease of T-cell proliferation and IL-2 production induced by AFB1. It was concluded that AFB1 inhibits anti-CD3-induced lymphocyte proliferation and IL-2 production by the oxidative stress mediated ERK1/2 MAPK signaling pathway.

  1. Effects of Nutrients in Substrates of Different Grains on Aflatoxin B1 Production by Aspergillus flavus

    PubMed Central

    Liu, Jie; Sun, Lvhui; Zhang, Niya; Zhang, Jiacai; Guo, Jiao; Li, Chong; Rajput, Shahid Ali; Qi, Desheng

    2016-01-01

    The current study was to better understand the potential factors affecting aflatoxin B1 (AFB1) accumulation varies between different grains. The nutrient composition and contents of defatted substrates were determined; additionally, according to the nutrient content of the substrates, the effects of starch, soluble sugars, amino acids, and trace elements on AFB1 production and mycelial growth in Czapek-Dox medium were examined. These results verified that removal of lipids from ground substrates significantly reduced the substrate's potential for AFB1 production by Aspergillus flavus. Maltose, glucose, sucrose, arginine, glutamic acid, aspartic acid, and zinc significantly induced AFB1 production up to 1.7- to 26.6-fold. And stachyose more significantly promoted A. flavus growth than the other nutrients. Thus, this study demonstrated that, combined with the nutrients content of grains, in addition to lipids, sucrose, stachyose, glutamic acid, and zinc might play key roles in various grains that are differentially infected by A. flavus. Particularly, two new nutrients (arginine and stachyose) of the grains we found significantly stimulate AFB1 production and A. flavus growth, respectively. The results provide new concepts for antifungal methods to protect food and animal feed from AFB1 contamination. PMID:27294129

  2. Effect of Various Compounds Blocking the Colony Pigmentation on the Aflatoxin B1 Production by Aspergillus flavus

    PubMed Central

    Dzhavakhiya, Vitaly G.; Voinova, Tatiana M.; Popletaeva, Sofya B.; Statsyuk, Natalia V.; Limantseva, Lyudmila A.; Shcherbakova, Larisa A.

    2016-01-01

    Aflatoxins and melanins are the products of a polyketide biosynthesis. In this study, the search of potential inhibitors of the aflatoxin B1 (AFB1) biosynthesis was performed among compounds blocking the pigmentation in fungi. Four compounds—three natural (thymol, 3-hydroxybenzaldehyde, compactin) and one synthetic (fluconazole)—were examined for their ability to block the pigmentation and AFB1 production in Aspergillus flavus. All compounds inhibited the mycelium pigmentation of a fungus growing on solid medium. At the same time, thymol, fluconazole, and 3-hydroxybenzaldehyde stimulated AFB1 accumulation in culture broth of A. flavus under submerged fermentation, whereas the addition of 2.5 μg/mL of compactin resulted in a 50× reduction in AFB1 production. Moreover, compactin also suppressed the sporulation of A. flavus on solid medium. In vivo treatment of corn and wheat grain with compactin (50 μg/g of grain) reduced the level of AFB1 accumulation 14 and 15 times, respectively. Further prospects of the compactin study as potential AFB1 inhibitor are discussed. PMID:27801823

  3. Hetero-enzyme-based two-round signal amplification strategy for trace detection of aflatoxin B1 using an electrochemical aptasensor.

    PubMed

    Zheng, Wanli; Teng, Jun; Cheng, Lin; Ye, Yingwang; Pan, Daodong; Wu, Jingjing; Xue, Feng; Liu, Guodong; Chen, Wei

    2016-06-15

    An electrochemical aptasensor for trace detection of aflatoxin B1 (AFB1) was developed by using an aptamer as the recognition unit while adopting the telomerase and EXO III based two-round signal amplification strategy as the signal enhancement units. The telomerase amplification was used to elongate the ssDNA probes on the surface of gold nanoparticles, by which the signal response range of the signal-off model electrochemical aptasensor could be correspondingly enlarged. Then, the EXO III amplification was used to hydrolyze the 3'-end of the dsDNA after the recognition of target AFB1, which caused the release of bounded AFB1 into the sensing system, where it participated in the next recognition-sensing cycle. With this two-round signal amplified electrochemical aptasensor, target AFB1 was successfully measured at trace concentrations with excellent detection limit of 0.6*10(-4)ppt and satisfied specificity due to the excellent affinity of the aptamer against AFB1. Based on this designed two-round signal amplification strategy, both the sensing range and detection limit were greatly improved. This proposed ultrasensitive electrochemical aptasensor method was also validated by comparison with the classic instrumental methods. Importantly, this hetero-enzyme based two-round signal amplified electrochemical aptasensor offers a great promising protocol for ultrasensitive detection of AFB1 and other mycotoxins by replacing the core recognition sequence of the aptamer.

  4. Determination of aflatoxin B1 levels in organic spices and herbs.

    PubMed

    Tosun, Halil; Arslan, Recep

    2013-01-01

    Organically produced spices and herbs were analyzed for determination of aflatoxin B1 (AFB1) by ELISA using immunoaffinity column. For this purpose 93 organic spices and 37 organic herbs were randomly selected from organic markets and organic shops in Turkey. AFB1 was detected in 58 organic spice and 32 organic herb samples. Among organic spice samples, the maximum value was detected in cinnamon sample (53 μg/kg). AFB1 was not detected in thyme samples. AFB1 levels of 41 organic spice samples were above the EU regulatory limit (5 μg/kg). Among organic herb samples the highest concentration of AFB1 (52.5 μg/kg) was detected in a rosehip sample. AFB1 levels of 21 organic herb samples were above the regulatory limits of the European Union. These results showed that more stringent measures must be taken for the prevention of mold contamination in the production of organic spices and herbs.

  5. Effects of aflatoxin B₁, fumonisin B₁ and their mixture on the aryl hydrocarbon receptor and cytochrome P450 1A induction.

    PubMed

    Mary, Verónica S; Valdehita, Ana; Navas, José M; Rubinstein, Héctor R; Fernández-Cruz, María L

    2015-01-01

    Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins widely found as cereal contaminants and their co-occurrence in corn has been associated with a high incidence of liver cancer. Both toxins are immunotoxic, with AFB1 being a procarcinogen, and its bioactivation through specific cytochrome P450 (Cyp) enzymes, such as Cyp1A, being a requirement for hepatocarcinogenic and toxic activities. This study evaluated the effects of these mycotoxins, alone or combined, on activation and expression of Cyp1A and its transcription factor aryl hydrocarbon receptor (Ahr) in hepatoma cell line H4IIE and spleen mononuclear cells of rats. The results demonstrate that in H4IIE cells, AFB1 induced an increase in Cyp1A activity and cyp1A transcription, associated with an enhanced Ahr activity, which suggests that this toxin can act as an Ahr agonist. Moreover, FB1 caused a small rise in Cyp1A activity and cyp1A expression. Similarly in spleen cells, AFB1 and FB1 induced overexpression of cyp1A and ahr genes. This work shows that the response potency was significantly higher for the mixture, indicating the existence of an interaction between both toxins. This study proposes the Ahr pathway activation as a toxicity mechanism of AFB1 and FB1, and highlights that FB1 may increase AFB1 bioactivation.

  6. Aflatoxin B1 Detection Using a Highly-Sensitive Molecularly-Imprinted Electrochemical Sensor Based on an Electropolymerized Metal Organic Framework

    PubMed Central

    Jiang, Mengjuan; Braiek, Mohamed; Florea, Anca; Chrouda, Amani; Farre, Carole; Bonhomme, Anne; Bessueille, Francois; Vocanson, Francis; Zhang, Aidong; Jaffrezic-Renault, Nicole

    2015-01-01

    A sensitive electrochemical molecularly-imprinted sensor was developed for the detection of aflatoxin B1 (AFB1), by electropolymerization of p-aminothiophenol-functionalized gold nanoparticles in the presence of AFB1 as a template molecule. The extraction of the template leads to the formation of cavities that are able to specifically recognize and bind AFB1 through π-π interactions between AFB1 molecules and aniline moities. The performance of the developed sensor for the detection of AFB1 was investigated by linear sweep voltammetry using a hexacyanoferrate/hexacyanoferrite solution as a redox probe, the electron transfer rate increasing when the concentration of AFB1 increases, due to a p-doping effect. The molecularly-imprinted sensor exhibits a broad linear range, between 3.2 fM and 3.2 µM, and a quantification limit of 3 fM. Compared to the non-imprinted sensor, the imprinting factor was found to be 10. Selectivity studies were also performed towards the binding of other aflatoxins and ochratoxin A, proving good selectivity. PMID:26371042

  7. Aflatoxin B1 Detection Using a Highly-Sensitive Molecularly-Imprinted Electrochemical Sensor Based on an Electropolymerized Metal Organic Framework.

    PubMed

    Jiang, Mengjuan; Braiek, Mohamed; Florea, Anca; Chrouda, Amani; Farre, Carole; Bonhomme, Anne; Bessueille, Francois; Vocanson, Francis; Zhang, Aidong; Jaffrezic-Renault, Nicole

    2015-09-07

    A sensitive electrochemical molecularly-imprinted sensor was developed for the detection of aflatoxin B1 (AFB1), by electropolymerization of p-aminothiophenol-functionalized gold nanoparticles in the presence of AFB1 as a template molecule. The extraction of the template leads to the formation of cavities that are able to specifically recognize and bind AFB1 through π-π interactions between AFB1 molecules and aniline moities. The performance of the developed sensor for the detection of AFB1 was investigated by linear sweep voltammetry using a hexacyanoferrate/hexacyanoferrite solution as a redox probe, the electron transfer rate increasing when the concentration of AFB1 increases, due to a p-doping effect. The molecularly-imprinted sensor exhibits a broad linear range, between 3.2 fM and 3.2 µM, and a quantification limit of 3 fM. Compared to the non-imprinted sensor, the imprinting factor was found to be 10. Selectivity studies were also performed towards the binding of other aflatoxins and ochratoxin A, proving good selectivity.

  8. Glutathione-S-transferase A3 knockout mice are sensitive to acute cytotoxic and genotoxic effects of aflatoxin B1

    SciTech Connect

    Ilic, Zoran; Crawford, Dana; Egner, Patricia A.; Sell, Stewart

    2010-02-01

    Aflatoxin B1 (AFB1) is a major risk factor for hepatocellular carcinoma (HCC) in humans. However, mice, a major animal model for the study of AFB1 carcinogenesis, are resistant, due to high constitutive expression, in the mouse liver, of glutathione S-transferase A3 subunit (mGSTA3) that is lacking in humans. Our objective was to establish that a mouse model for AFB1 toxicity could be used to study mechanisms of toxicity that are relevant for human disease, i.e., an mGSTA3 knockout (KO) mouse that responds to toxicants such as AFB1 in a manner similar to humans. Exons 3-6 of the mGSTA3 were replaced with a neomycin cassette by homologous recombination. Southern blotting, RT-PCR, Western blotting, and measurement of AFB1-N{sup 7}-DNA adduct formation were used to evaluate the mGSTA3 KO mice. The KO mice have deletion of exons 3-6 of the mGSTA3 gene, as expected, as well as a lack of mGSTA3 expression at the mRNA and protein levels. Three hours after injection of 5 mg/kg AFB1, mGSTA3 KO mice have more than 100-fold more AFB1-N{sup 7}-DNA adducts in their livers than do similarly treated wild-type (WT) mice. In addition, the mGSTA3 KO mice die of massive hepatic necrosis, at AFB1 doses that have minimal toxic effects in WT mice. We conclude that mGSTA3 KO mice are sensitive to the acute cytotoxic and genotoxic effects of AFB1, confirming the crucial role of GSTA3 subunit in protection of normal mice against AFB1 toxicity. We propose the mGSTA3 KO mouse as a useful model with which to study the interplay of risk factors leading to HCC development in humans, as well as for testing of additional possible functions of mGSTA3.

  9. Growth, serum biochemistry, complement activity, and liver gene expression responses of Pekin ducklings to graded levels of cultured aflatoxin B1.

    PubMed

    Chen, X; Horn, N; Cotter, P F; Applegate, T J

    2014-08-01

    A 14-d study was conducted to evaluate the effects of cultured aflatoxin B1 (AFB1) on performance, serum biochemistry, serum natural antibody and complement activity, and hepatic gene expression parameters in Pekin ducklings. A total of 144 male Pekin ducklings were weighed, tagged, and randomly allotted to 4 dietary treatments containing 4 concentrations of AFB1 (0, 0.11, 0.14, and 0.21 mg/kg) from 0 to 14 d of age (6 cages per diet; 6 ducklings per cage). Compared with the control group, there was a 10.9, 31.7, and 47.4% (P < 0.05) decrease in cumulative BW gain with 0.11, 0.14, and 0.21 mg of AFB1/kg of diet, respectively, but feed efficiency was not affected. Increasing concentrations of AFB1 reduced cumulative BW gain and feed intake both linearly and quadratically, and regression equations were developed with r(2) ≥0.73. Feeding 0.11 to 0.21 mg of AFB1/kg reduced serum glucose, creatinine, albumin, total protein, globulin, Ca, P, and creatine phosphokinase linearly, whereas serum urea N, Cl, alkaline phosphatase, and aspartate amino transferase concentrations increased linearly with increasing AFB1 (P < 0.05). Additionally, 0.11 to 0.21 mg of AFB1/kg diets impaired classical and alternative complement pathways in the duckling serum when tested by lysis of rabbit, human type O, and horse erythrocytes, and decreased rabbit and horse agglutinins (P < 0.05). Liver peroxisome proliferator activated receptor α (PPARα) expression was linearly downregulated by AFB1 (P < 0.01). Results from this study indicate that for every 0.10 mg/kg increase in dietary AFB1, cumulative feed intake and BW gain decrease approximately 230 and 169 g per duckling from hatch to 14 d; and that AFB1 at very low concentrations can significantly impair liver function and gene expression, and innate immune dynamics in Pekin ducklings.

  10. A SERS-active sensor based on heterogeneous gold nanostar core-silver nanoparticle satellite assemblies for ultrasensitive detection of aflatoxinB1

    NASA Astrophysics Data System (ADS)

    Li, Aike; Tang, Lijuan; Song, Dan; Song, Shanshan; Ma, Wei; Xu, Liguang; Kuang, Hua; Wu, Xiaoling; Liu, Liqiang; Chen, Xin; Xu, Chuanlai

    2016-01-01

    A surface-enhanced Raman scattering (SERS) sensor based on gold nanostar (Au NS) core-silver nanoparticle (Ag NP) satellites was fabricated for the first time to detect aflatoxinB1 (AFB1). We constructed the SERS sensor using AFB1 aptamer (DNA1)-modified Ag satellites and a complementary sequence (DNA2)-modified Au NS core. The Raman label (ATP) was modified on the surface of Ag satellites. The SERS signal was enhanced when the satellite NP was attached to the Au core NS. The AFB1 aptamer on the surface of Ag satellites would bind to the targets when AFB1 was present in the system, Ag satellites were then removed and the SERS signal decreased. This SERS sensor showed superior specificity for AFB1 and the linear detection range was from 1 to 1000 pg mL-1 with the limit of detection (LOD) of 0.48 pg mL-1. The excellent recovery experiment using peanut milk demonstrated that the sensor could be applied in food and environmental detection.A surface-enhanced Raman scattering (SERS) sensor based on gold nanostar (Au NS) core-silver nanoparticle (Ag NP) satellites was fabricated for the first time to detect aflatoxinB1 (AFB1). We constructed the SERS sensor using AFB1 aptamer (DNA1)-modified Ag satellites and a complementary sequence (DNA2)-modified Au NS core. The Raman label (ATP) was modified on the surface of Ag satellites. The SERS signal was enhanced when the satellite NP was attached to the Au core NS. The AFB1 aptamer on the surface of Ag satellites would bind to the targets when AFB1 was present in the system, Ag satellites were then removed and the SERS signal decreased. This SERS sensor showed superior specificity for AFB1 and the linear detection range was from 1 to 1000 pg mL-1 with the limit of detection (LOD) of 0.48 pg mL-1. The excellent recovery experiment using peanut milk demonstrated that the sensor could be applied in food and environmental detection. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr08372a

  11. Rapid and label-free detection of ochratoxin A and aflatoxin B1 using an optical portable instrument.

    PubMed

    Arduini, Fabiana; Neagu, Daniela; Pagliarini, Valeria; Scognamiglio, Viviana; Leonardis, Maria Antonietta; Gatto, Emanuela; Amine, Aziz; Palleschi, Giuseppe; Moscone, Danila

    2016-04-01

    In this study, we report a novel assay for the combined on site detection of aflatoxin B1 (AFB1) and ochratoxin A (OTA), through a colorimetric biosensing system for AFB1 and a fluorimetric detection for OTA, exploiting the capability of the portable fibre optic spectrometer to perform both analyses. AFB1 was detected using the acetylcholinesterase (AChE) enzyme that is inhibited by this toxin, and the degree of inhibition was quantified by the Ellman's spectrophotometric method, obtaining a detection limit of 10 µg L(-1). OTA quantification was performed by monitoring its intrinsic fluorescence in methanol, reaching a detection limit of 0.1 µg L(-1). In order to successfully apply the analytical tool in the food analysis, immunoaffinity columns were used. Clean-up and quantification of both AFB1 and OTA in millet samples was obtained by HPLC-dedicated AflaOchra-Test HPLC™ (Vicam™) and Afla-OtaCLEAN™ (LC-Tech) immunoaffinity columns, followed by absorption/fluorescence detection. Millet samples which were fortified with both OTA (50 µg kg(-1)) and AFB1 (20 µg kg(-1)), gave recovery values of 100 ± 6% for OTA, and 110 ± 10% for AFB1, using AflaOchra-Test HPLC™. Single OTA clean-up and quantification in wine samples was obtained, using an OchraTest immunoaffinity column (Vicam™), reaching a detection limit of 0.3 µg L(-1) and recovery values between 80% and 120%. These results demonstrated the possibility of employing a single clean-up and a cost-effective, and easy to use analytical system for both AFB1 and OTA detection at µg kg(-1) (ppb) level. Furthermore, in the case of positive samples, they could be analysed further, using standard chromatographic procedures, without any additional clean-up step, since the same extraction procedure of standard method is proposed in our method.

  12. Mutational spectra of aflatoxin B1 in vivo establish biomarkers of exposure for human hepatocellular carcinoma.

    PubMed

    Chawanthayatham, Supawadee; Valentine, Charles C; Fedeles, Bogdan I; Fox, Edward J; Loeb, Lawrence A; Levine, Stuart S; Slocum, Stephen L; Wogan, Gerald N; Croy, Robert G; Essigmann, John M

    2017-04-11

    Aflatoxin B1 (AFB1) and/or hepatitis B and C viruses are risk factors for human hepatocellular carcinoma (HCC). Available evidence supports the interpretation that formation of AFB1-DNA adducts in hepatocytes seeds a population of mutations, mainly G:C→T:A, and viral processes synergize to accelerate tumorigenesis, perhaps via inflammation. Responding to a need for early-onset evidence predicting disease development, highly accurate duplex sequencing was used to monitor acquisition of high-resolution mutational spectra (HRMS) during the process of hepatocarcinogenesis. Four-day-old male mice were treated with AFB1 using a regimen that induced HCC within 72 wk. For analysis, livers were separated into tumor and adjacent cellular fractions. HRMS of cells surrounding the tumors revealed predominantly G:C→T:A mutations characteristic of AFB1 exposure. Importantly, 25% of all mutations were G→T in one trinucleotide context (CGC; the underlined G is the position of the mutation), which is also a hotspot mutation in human liver tumors whose incidence correlates with AFB1 exposure. The technology proved sufficiently sensitive that the same distinctive spectrum was detected as early as 10 wk after dosing, well before evidence of neoplasia. Additionally, analysis of tumor tissue revealed a more complex pattern than observed in surrounding hepatocytes; tumor HRMS were a composite of the 10-wk spectrum and a more heterogeneous set of mutations that emerged during tumor outgrowth. We propose that the 10-wk HRMS reflects a short-term mutational response to AFB1, and, as such, is an early detection metric for AFB1-induced liver cancer in this mouse model that will be a useful tool to reconstruct the molecular etiology of human hepatocarcinogenesis.

  13. Vitamin E supplementation ameliorates aflatoxin B1-induced nephrotoxicity in rats.

    PubMed

    Abdel-Hamid, Ahmed A M; Firgany, Alaa El-Din L

    2015-10-01

    Fungal toxins in nutrition can cause organ dysfunction or even failure. Aflatoxin B1 (AFB1)-induced renal impairment is not sufficiently studied regarding its extent and prevention. The aim of this experiment was to study the effect of AFB1 on renal cortical tissue and whether its possible harmful effect could be prevented by the conventional economical antioxidant, vitamin E. Forty rats were divided into four groups; I-IV. Group I represented the control while the others received vitamin E (Vit E), AFB1 and AFB1+Vit E, respectively. Renal cortex specimens were taken from each group after 25 days. Then, specimens were prepared for histological study by hematoxlyin and eosin (H&E), Masson's trichrome, caspase-3 as well as for ultrastructural examination and oxidative stress parameters evaluation. Data were morphometrically and statistically analyzed. In AFB1-treated group, focal tubulo-interstitial affection in the form of tubular cytoplasmic vacuolation, mitochondrial disruption, numerous lysosomes, marked increase in collagen deposition and in caspase-3 expression were observed. Glomerular impairment in the form of fusion of podocytes enlarged foot processes and thickening of the glomerular basement membrane (GBM) with loss of its trilaminar appearance were detected. In the group treated by AFB1+Vit E, there were minimal affection of the histological structure of the renal cortex as well as significant increase in the anti-oxidative parameters which were significantly decreased in the AFB1-treated group. Therefore, Vit E could be considered in wide experimental studies to be a first choice antioxidant of high cost-effectiveness in prevention of fungal toxins pro-oxidant-induced renal impairment.

  14. Aflatoxin B1 Degradation by Stenotrophomonas Maltophilia and Other Microbes Selected Using Coumarin Medium#

    PubMed Central

    Guan, Shu; Ji, Cheng; Zhou, Ting; Li, Junxia; Ma, Qiugang; Niu, Tiangui

    2008-01-01

    Aflatoxin B1 (AFB1) is one of the most harmful mycotoxins in animal production and food industry. A safe, effective and environmentally sound detoxification method is needed for controlling this toxin. In this study, 65 samples were screened from various sources with vast microbial populations using a newly developed medium containing coumarin as the sole carbon source. Twenty five single-colony bacterial isolates showing AFB1 reduction activity in a liquid culture medium were selected from the screen. Isolate 35-3, obtained from tapir feces and identified to be Stenotrophomonas maltophilia, reduced AFB1 by 82.5% after incubation in the liquid medium at 37 °C for 72 h. The culture supernatant of isolate 35-3 was able to degrade AFB1 effectively, whereas the viable cells and cell extracts were far less effective. Factors influencing AFB1 degradation by the culture supernatant were investigated. Activity was reduced to 60.8% and 63.5% at 20 °C and 30 °C, respectively, from 78.7% at 37 °C. The highest degradation rate was 84.8% at pH 8 and the lowest was only 14.3% at pH 4.0. Ions Mg2+ and Cu2+ were activators for AFB1 degradation, however ion Zn2+ was a strong inhibitor. Treatments with proteinase K, proteinase K plus SDS and heating significantly reduced or eradicated the degradation activity of the culture supernatant. The results indicated that the degradation of AFB1 by S. maltophilia 35-3 was enzymatic and could have a great potential in industrial applications. PMID:19325817

  15. Abiotic factors and their interactions influence on the co-production of aflatoxin B(1) and cyclopiazonic acid by Aspergillus flavus isolated from corn.

    PubMed

    Astoreca, Andrea; Vaamonde, Graciela; Dalcero, Ana; Marin, Sonia; Ramos, Antonio

    2014-04-01

    The objectives of this study were i) to determine the effects of the interactions of water activity, temperature and incubation time on the co-production of AFB1 and CPA by isolates of Aspergillus flavus with different profile of mycotoxin production and ii) to identify the aW and temperature limiting conditions for the production of both mycotoxins. Fungi used in this study were selected because they belonged to different chemotypes: chemotype I (AFB1+/CPA+), III (AFB1+/CPA-) and IV (AFB1-/CPA+), respectively. Two culture media were used; Czapek yeast agar (CYA) and corn extract agar (CEM), at different incubated temperatures (10-40 °C) and aW levels (0.80-0.98). AFB1 and CPA production were analyzed after 7, 14, 21 and 28 days of incubation. Significant differences were observed with respect to mycotoxin production depending on the media evaluated. The AFB1 production occurred more favorably on CYA while the highest CPA concentrations were recorded on CEM. Within the range of aW evaluated in this study, 0.83 was the limiting level for both toxins production. The optimum conditions for AFB1 production occurred at 0.96 aW and 30 °C after 21 days of incubation, regardless of the media and isolate. Although different amounts of toxins were produced in each medium, the limiting and optimum conditions for their production were similar in both. No differences in the response of the three isolates to the abiotic factors discussed were observed despite belonging to different chemotypes. The determination of the thresholds of mycotoxins co-production, especially in the case of data obtained with the corn extract medium can be useful to avoid the conditions conducive to co-occurrence of these mycotoxins in corn.

  16. Initiation, promotion, and inhibition of carcinogenesis in rainbow trout

    SciTech Connect

    Bailey, G.; Selivonchick, D.; Hendricks, J.

    1987-04-01

    The identification of etiological agents in feral fish neoplasia epizootics has been hampered in part by the lack of suitable fish models, and complicated by the likely existence of environmental agents which can act to stimulate or reduce population responses to genotoxin insult. The response of fish to tumor inhibitors and promoters, and the underlying mechanisms of modulation, have been studied in the rainbow trout model. Dietary treatment of trout with the compounds indole-3-carbinol (I3C), ..beta..-napthroflavone (BNF), or the polychlorinated biphenyl (PCB) complex Aroclor 1254, before and during exposure to aflatoxin B/sub 1/ (AFB1), was shown to reduce the final incidence of hepatocellular carcinoma after 12 months, compared to fish receiving AFB1 only. By contrast, treatment of trout with BNF or I3C following AFB1 initiation led to a significant enhancement of ultimate tumor response, Similarly, simultaneous treatment of trout with PCB and the carcinogen N-nitrosodiethylamine led to syncarcinogenic enhancement, rather than inhibition, of tumor response. Mechanisms of inhibition of AFB1 carcinogenesis by PCB, BNF, and I3C were investigated. PCB and BNF, but not I3C, are known to be strong inducers of trout cytochrome P448 and associated activities. Dietary induction by BNF or PCB was shown to be accompanied in solvated hepatocytes by considerably altered AFB1 metabolism, and by significantly reduced rates of DNA adduct formation for all three agents. All agents differentially altered in vivo AFB1 pharmacokinetics, enhanced bile elimination of AFB1 as the aflatoxicol-M1 glucuronide, and significantly reduced peak levels of liver DNA adduct formation.

  17. Comparative in vitro and ex-vivo myelotoxicity of aflatoxins B1 and M1 on haematopoietic progenitors (BFU-E, CFU-E, and CFU-GM): species-related susceptibility.

    PubMed

    Roda, E; Coccini, T; Acerbi, D; Castoldi, A F; Manzo, L

    2010-02-01

    Haemato- and myelotoxicity are adverse effects caused by mycotoxins. Due to the relevance of aflatoxins to human health, the present study, employing CFU-GM-, BFU-E- and CFU-E-clonogenic assays, aimed at (i) comparing, in vitro, the sensitivity of human vs. murine haematopoietic progenitors to AFB1 and AFM1 (0.001-50microg/ml), (ii) assessing whether a single AFB1 in vivo treatment (0.3-3mg/kgb.w.) alters the ability of murine bone marrow cells to form myeloid and erythroid colonies, and (iii) comparing the in vitro with the in vitro ex-vivo data. We demonstrated (i) species-related sensitivity to AFB1, showing higher susceptibility of human myeloid and erythroid progenitors (IC(50) values: about 4 times lower in human than in murine cells), (ii) higher sensitivity of CFU-GM and BFU-E colonies, both more markedly affected, particularly by AFB1 (IC(50): 2.45+/-1.08 and 1.82+/-0.8microM for humans, and 11.08+/-2.92 and 1.81+/-0.20microM for mice, respectively), than the mature CFU-E (AFB1 IC(50): 12.58+/-5.4 and 40.27+/-6.05microM), irrespectively of animal species, (iii) regarding AFM1, a species- and lineage-related susceptibility similar to that observed for AFB1 and (iv) lack of effects after AFB1 in vivo treatment on the proliferation of haematopoietic colonies.

  18. A novel mycotoxin purification system using magnetic nanoparticles for the recovery of aflatoxin B1 and zearalenone from feed

    PubMed Central

    Kim, Hyun-Jung; Kim, Sung-Hee; Lee, Jin-Kyu; Choi, Cheong-Up; Lee, Hee-Soo

    2012-01-01

    In this study, we developed a novel tool for purifying two mycotoxins, aflatoxin B1 (AFB1) and zearalenone (ZEN), in feed. This system utilized monoclonal antibodies (mAbs) against AFB1 and ZEN, and magnetic nanoparticles (MNPs). Among ten MNPs with different diameters and functional groups, a 100-nm diameter MNP (fMA) conjugated to an amine group (-NH2) was found to be optimum for coupling with mAbs. The optimal mAb concentrations for coupling to the fMA along with mycotoxin purification capacities of the fMA-mAb conjugates (fMA-AFB1 and fMA-ZEN) were determined. A comparison of mean recovery rates (from corn and product X feed) between the fMA-mAb conjugates and immunoaffinity columns (IAC-AFB1 and IAC-ZEN) showed that the rate for fMA-AFB1 (90~92% and 81~88%) was higher (p > 0.05) than that of IAC-AFB1 (81~84% and 72~78%) for AFB1 (5, 10, 15 ng/mL), and the rate for fMA-ZEN (99~100% and 92~94%) was significantly higher (p < 0.01) than that of IAC-ZEN (86~88% and 81~88%) for ZEN (10, 25, 50 ng/mL) except at a concentration of 10 ng/mL, demonstrating the remarkable purification efficiency of the novel fMA-mAb method. Additionally, mycotoxin purification was much faster using our novel method (approx. 5 min) than the IAC-based technique (> 30 min). This study suggests that the novel purification system we developed would be a useful tool for monitoring and regulating mycotoxin contamination in feed, and replace IAC methods. PMID:23271177

  19. Prevention of maternal and developmental toxicity in rats via dietary inclusion of common aflatoxin sorbents: potential for hidden risks.

    PubMed

    Mayura, K; Abdel-Wahhab, M A; McKenzie, K S; Sarr, A B; Edwards, J F; Naguib, K; Phillips, T D

    1998-02-01

    In earlier work, we have reported that a phyllosilicate clay (HSCAS or NovaSil) can tightly and selectively bind the aflatoxins in vitro and in vivo. Since then, a variety of untested clay and zeolitic minerals have been added to poultry and livestock feeds as potential "aflatoxin binders." However, the efficacy and safety of these products have not been determined. A common zeolite that has been frequently added to animal feed is clinoptilolite. Our objectives in this study were twofold: (1) to utilize the pregnant rat as an in vivo model to compare the potential of HSCAS and clinoptilolite to prevent the developmental toxicity of aflatoxin B1 (AfB1), and (2) to determine the effect of these two sorbents on the metabolism and bioavailability of AfB1. Clay and zeolitic minerals (HSCAS or clinoptilolite) were added to the diet at a level of 0.5% (w/w) and fed to pregnant Sprague-Dawley rats throughout pregnancy (i.e., day 0 to 20). Treatment groups (HSCAS or clinoptilolite) alone and in combination with AfB1 were exposed to sorbents in the feed as well as by gavage. Untreated and AfB1 control animals were fed the basal diet without added sorbent. Between gestation days 6 and 13, animals maintained on diets containing sorbent were gavaged with corn oil in combination with an amount of the respective sorbent equivalent to 0.5% of the estimated maximum daily intake of feed. Animals receiving AfB1 were dosed orally (between days 6 and 13) with AfB1 (2 mg/kg body wt) either alone or concomitantly with a similar quantity of the respective sorbent. Evaluations of toxicity were performed on day 20. These included: maternal (mortality, body weights, feed intake, and litter weights), developmental (embryonic resorptions and fetal body weights), and histological (maternal livers and kidneys). Sorbents alone were not toxic; AfB1 alone and with clinoptilolite resulted in significant maternal and developmental toxicity. Animals treated with HSCAS (plus AfB1) were comparable to controls. Importantly, clinoptilolite (plus AfB1) resulted in severe maternal liver lesions (more severe than AfB1 alone), suggesting that this zeolite may interact with dietary components that modulate aflatoxicosis. In metabolism studies, adult male Sprague-Dawley rats, maintained on diets containing 0.5% (w/w) HSCAS or clinoptilolite, were dosed orally with 2.0 mg AfB1/kg body wt. The concentration of the major urinary metabolite (AfM1) was considerably decreased in the presence of HSCAS. These results suggest that the mechanism of protection of AfB1-induced maternal and developmental toxicities in the rat may involve adsorption and reduction of AfB1 bioavailability in vivo. Importantly, this study demonstrates the potential for significant hidden risks associated with the inclusion of nonselective aflatoxin binders in feeds. Aflatoxin sorbents should be rigorously tested individually and thoroughly characterized in vivo, paying particular attention to their effectiveness and safety in sensitive animal models and their potential for deleterious interactions.

  20. Associations of serum aflatoxin B1-lysine adduct level with socio-demographic factors and aflatoxins intake from nuts and related nut products in Malaysia.

    PubMed

    Leong, Yin-Hui; Rosma, Ahmad; Latiff, Aishah A; Izzah, A Nurul

    2012-04-01

    Aflatoxins are one of the major risk factors in the multi-factorial etiology of human hepatocellular carcinoma. Therefore, the information on aflatoxins exposure is very important in the intervention planning in order to reduce the dietary intake of aflatoxins, especially among the children. This study investigated the relationship between aflatoxin B(1) (AFB(1)) lysine adduct levers in serum and socio-demographic factors and dietary intake of aflatoxins from nuts and nut products in Penang, Malaysia. A cross-sectional field study was conducted in five districts of Penang. A survey on socio-demographic characteristics was administered to 364 healthy adults from the three main ethnic groups (Malay, Chinese and Indian). A total of 170 blood samples were successfully collected and tested for the level of AFB(1)-lysine adduct. 97% of the samples contained AFB(1)-lysine adduct above the detection limit of 0.4 pg/mg albumin and ranged from 0.20 to 23.16 pg/mg albumin (mean±standard deviation=7.67±4.54 pg/mg albumin; median=7.12 pg/mg albumin). There was no significant association between AFB(1)-lysine adduct levels with gender, district, education level, household number and occupation when these socio-demographic characteristics were examined according to high or low levels of AFB(1)-lysine. However, participants in the age group of 31-50 years were 3.08 times more likely to have high AFB(1) levels compared to those aged between 18 and 30 years (P=0.026). Significant difference (P=0.000) was found among different ethnic groups. Chinese and Indian participants were 3.05 and 2.35 times more likely to have high AFB(1) levels than Malay. The result of AFB(1)-lysine adduct suggested that Penang adult population is likely to be exposed to AFB(1) but at a level of less than that needed to cause direct acute illness or death.

  1. Carcinogen-nucleic acid interactions: Equilibrium binding studies of aflatoxin B sub 1 with the oligodeoxynucleotide d(ATGCAT) sub 2 and with plasmid pBR322 support intercalative association with the B-DNA helix

    SciTech Connect

    Gopalakrishnan, S.; Byrd, S.; Stone, M.P.; Harris, T.M. )

    1989-01-24

    Equilibrium binding of aflatoxin B{sub 1} (AFB1) to the oligodeoxynucleotide d(ATGCAT){sub 2} was examined by using {sup 1}H NMR. AFB1 binds to double-stranded d(ATGCAT){sub 2} with an apparent binding constant of 3.7 {times} 10{sup 3} M{sup {minus}1}. The equilibrium is rapid on the NMR time scale; the observed {sup 1}H NMR spectrum represents the population-weighted average of the chemical shifts arising from the free and bound states of the oligodeoxynucleotide and the AFB1. The spectrum of d(ATGCAT){sub 2} exhibits exchange broadening in the presence of AFB1, manifested as decreases in apparent T{sub 2} relaxation times for the d(ATGCAT){sub 2} base protons. Upon binding to d(ATGCAT){sub 2}, the AFB1 signals are shifted upfield, indicative of increased shielding. The adenine H2 protons are also shifted upfield in the presence of the carcinogen. Small changes in chemical shift are observed for other d(ATGCAT){sub 2} protons. Proton NOESY experiments confirmed that the overall conformation for the d(ATGCAT){sub 2} duplex was right-handed both in the absence and in the presence of AFB1. Equilibrium binding of AFB1 to d(ATGCAT){sub 2} is greatly diminished at higher temperatures at which the oligodeoxynucleotide is single-stranded. A series of experiments were performed in which the T{sub m} of d(ATGCAT){sub 2} was increased by increasing the total oligodeoxynucleotide concentration; these experiments showed that AFB1 would bind to d(ATGCAT){sub 2} at higher temperatures provided that the DNA was in double-stranded form. The results of these experiments provide strong evidence that noncovalent binding of AFB1 to B-form DNA involves the intercalation of the mycotoxin between base pairs; this intercalation could direct subsequent covalent attachment of the carcinogen at the N7 position of guanine.

  2. Reduction of aflatoxins (B₁, B₂, G₁, and G₂) in soybean-based model systems.

    PubMed

    Lee, Jongin; Her, Jae-Young; Lee, Kwang-Geun

    2015-12-15

    The effects of chemical, physical, and cooking treatments on the reduction of aflatoxin B1 (AFB1), B2, G1, and G2 in soybean matrix were investigated. A HPLC-FLD with a Kobra cell system was used for the quantitative analysis of aflatoxins (AFs). To decrease the level of AFs during the soaking process, the contaminated soybeans were submerged in organic acid solutions. The reduction rates of AFB1 in 1.0N citric acid, lactic acid, succinic acid, and tartaric acid for 18h were 94.1%, 92.7%, 62.0%, and 95.1%, respectively. In the case of pH and autoclave treatment, the level of AFB1 was significantly decreased during autoclaving process at pH 7.4, 9.0, and 11.1, compared with the non-autoclaved samples (p<0.05). In the case of physical treatment, the heating process at 100 and 150°C for 90min significantly decreased the level of AFB1 by 41.9% and 81.2%, respectively (p<0.05). The reduction rate of AFB1 after cooking was 97.9% for soybean milk and 33.6% for steamed soybeans.

  3. Metabolism of aflatoxin B-1 in cotton bolls

    SciTech Connect

    Mellon, J.E.; Lee, L.S. )

    1989-04-01

    Aspergillus flavus is a fungus capable of producing the potent carcinogen aflatoxin (AFB-1) when it infects developing cotton seed. Although high levels of toxin can readily be isolated from internal tissues of infected seeds, very low toxin levels are observed in the fiber-linter matrix. In order to test the hypothesis that constituents associated with the lint of the host plant are metabolizing aflatoxin, {sup 14}C-AFB-1 was introduced into cotton bolls (30 days postanthesis). Other sets of bolls received inoculations of toxigenic or nontoxigenic strains of A. flavus plus exogenous {sup 14}C-AFB-1. In addition to the exogenously applied {sup 14}C-AFB-1, at least two new labelled metabolites were recovered from the test bolls. One of these metabolites was very polar and remained on the origin of the thin layer analysis system. Test bolls which received both A. flavus and AFB-1 produced significantly lower levels of this polar metabolite. Results indicated that some constituent(s) associated with cotton fiber may metabolize fungal-produced aflatoxin, rather than inhibit its formation.

  4. Aflatoxin B1 Induced Compositional Changes in Gut Microbial Communities of Male F344 Rats

    PubMed Central

    Wang, Jincheng; Tang, Lili; Glenn, Travis C.; Wang, Jia-Sheng

    2016-01-01

    Aflatoxins are a group of potent foodborne toxicants naturally occurring in maize and groundnuts. Differential species-specific sensitivity to aflatoxins has been documented but cannot be fully explained by the differences in metabolism of these toxicants among animal species. Commensal microbial communities (microbiota) are critical to human and animal health, but few studies have assessed interactions between xenobiotic toxins and those microbiota, and its potential effects to humans and animals. Here, an exploratory dosing experiment was conducted to explore effects of Aflatoxin B1 (AFB1) on the gut microbiota in a commonly used rat model. Male F344 rats were randomly divided into groups and treated with different concentrations of AFB1. Microbial communities in fecal samples were assessed using 16S rRNA sequence analysis. We found that samples from the control group had a phylogenetically diverse community, and that increasing AFB1 doses decreased this diversity but increased evenness of community composition. In addition, the gut microbiota from different samples was clustered according to their dosing regimens. There is no community shift at the phylum level but some lactic acid bacteria were significantly depleted by AFB1. These findings suggested that AFB1 could modify the gut microbiota in a dose-dependent manner. PMID:26612839

  5. Adverse Outcome Pathway (AOP) for a Mutagenic Mode of ...

    EPA Pesticide Factsheets

    AOPs provide a framework to describe a sequence of measureable key events (KEs), beginning with a molecular initiating event (MIE), followed by a series of identified KEs linked to one another by KE Relationships (KERs), all anchored by a specific adverse outcome (AO). Each KE/KER is supported by data and evaluated against criteria to assess biological plausibility, weight/strength of evidence, specificity, and confidence. AOPs offer an approach to using toxicological data and predictive modeling to actualize use of mode-of-action (MOA) for such purposes as read-across, integrated approaches to testing & assessment, and risk assessment. Different applications will depend partly on the scientific confidence underpinning each KE/KER and the overall AOP. An OECD program encourages development of AOPs, with a wiki that allows for public review & comment to foster collaborations and broaden understanding & application of AOPs. Developing an AOP for a mutagenic MOA for cancer as a case study in the OECD program lays a path towards determination of such an MOA and its use in chemical assessment programs. Aflatoxin B1 (AFB1), with ubiquitous exposure and a rich database, was selected for this case study. AFB1 has been determined to induce HCC via a DNA-reactive MOA in many species, including humans. The sequential KEs identified for AFB1 are as follows: pre-MIE: Hepatic metabolic activation; MIE: Formation of a pro-mutagenic DNA adduct (N7-AFB1-guanine or AFB1-FAPy); KE

  6. A fabricated electro-spun sensor based on Lake Red C pigments doped into PAN (polyacrylonitrile) nano-fibers for electrochemical detection of Aflatoxin B1 in poultry feed and serum samples.

    PubMed

    Babakhanian, Arash; Momeneh, Tahereh; Aberoomand-azar, Parviz; Kaki, Samineh; Torki, Mehran; Hossein Kiaie, Seyed; Sadeghi, Ehsan; Dabirian, Farzad

    2015-11-21

    The aim of this work was to fabricate a novel nano-fiber modified electrode, involving Lake Red C (LRC) pigments doped into electrospun polyacrylonitrile (PAN) fibrous films. Cyclic voltammetry (CV), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) techniques were used for electrochemical and morphological characterization of the composite fibers. This sensor responds to Aflatoxin B1 (AFB1) over the concentration range of 40-120 nM with high accuracy and precision in analysis. The modified electrode exhibited an excellent electrocatalytic ability (α = 0.42, log K(s) = 4.21 s(-1), and Γ = 1.49 × 10(-5) mmol cm(-2)) for reduction of AFB1 at the optimum pH of 6 and working potential of -0.75 V (vs. SCE). The common substances accompanying AFB1 had no serious interferences on the response of the modified electrode to AFB1. The modified electrode indicated reproducible behavior and a high level stability during the experiments, making it particularly suitable for the analytical determination of AFB1 in poultry feed and serum samples.

  7. Prevention of Aflatoxin B1-Induced DNA Breaks by β-D-Glucan

    PubMed Central

    Madrigal-Bujaidar, Eduardo; Morales-González, José Antonio; Sánchez-Gutiérrez, Manuel; Izquierdo-Vega, Jeannett A.; Reyes-Arellano, Alicia; Álvarez-González, Isela; Pérez-Pasten, Ricardo; Madrigal-Santillán, Eduardo

    2015-01-01

    Aflatoxins are a group of naturally-occurring carcinogens that are known to contaminate different human and animal foodstuffs. Aflatoxin B1 (AFB1) is the most genotoxic hepatocarcinogenic compound of all of the aflatoxins. In this report, we explore the capacity of β-d-glucan (Glu) to reduce the DNA damage induced by AFB1 in mouse hepatocytes. For this purpose, we applied the comet assay to groups of animals that were first administered Glu in three doses (100, 400 and 700 mg/kg bw, respectively) and, 20 min later, 1.0 mg/kg of AFB1. Liver cells were obtained at 4, 10 and 16 h after the chemical administration and examined. The results showed no protection of the damage induced by AFB1 with the low dose of the polysaccharide, but they did reveal antigenotoxic activity exerted by the two high doses. In addition, we induced a co-crystallization between both compounds, determined their fusion points and analyzed the molecules by UV spectroscopy. The data suggested the formation of a supramolecular complex between AFB1 and β-d-glucan. PMID:26110504

  8. Activated carbons as potentially useful non-nutritive additives to prevent the effect of fumonisin B1 on sodium bentonite activity against chronic aflatoxicosis.

    PubMed

    Monge, María Del Pilar; Magnoli, Alejandra Paola; Bergesio, Maria Virginia; Tancredi, Nestor; Magnoli, Carina E; Chiacchiera, Stella Maris

    2016-06-01

    Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB1 causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B1 and aflatoxin B1 are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB1 to AFB1 that mimics the natural occurrence (200:1), showed that FB1 greatly decreases the in vitro ability of NaB to adsorb AFB1. The ability of two activated carbons to adsorb FB1 was also investigated. Both carbons showed high affinity for FB1. A complex behaviour of the FB1 adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB1 and FB1, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis.

  9. Application of essential oils in maize grain: impact on Aspergillus section Flavi growth parameters and aflatoxin accumulation.

    PubMed

    Bluma, Romina V; Etcheverry, Miriam G

    2008-04-01

    The antifungal activity of Pimpinella anisum L. (anise), Pëumus boldus Mol (boldus), Hedeoma multiflora Benth (mountain thyme), Syzygium aromaticum L. (clove), and Lippia turbinate var. integrifolia (griseb) (poleo) essential oils (EOs) against Aspergillus section Flavi was evaluated in sterile maize grain under different water activity (a(w)) condition (0.982, 0.955, and 0.90). The effect of EOs added to maize grains on growth rate, lag phase, and aflatoxin B(1) (AFB(1)) accumulation of Aspergillus section Flavi were evaluated at different water activity conditions. The five EOs analyzed have been shown to influence lag phase and growth rate. Their efficacy depended mainly on the essential oil concentrations and substrate water activity conditions. All EOs showed significant impact on AFB(1) accumulation. This effect was closely dependent on the water activity, concentration, and incubation periods. Important reduction of AFB(1) accumulation was observed in the majority of EO treatments at 11 days of incubation. Boldus, poleo, and mountain thyme EO completely inhibited AFB(1) at 2000 and 3000 microg g(-1). Inhibition of AFB(1) accumulation was also observed when aflatoxigenic isolates grew with different concentration of EOs during 35 days.

  10. Quantifying Aflatoxin B1 in peanut oil using fabricating fluorescence probes based on upconversion nanoparticles

    NASA Astrophysics Data System (ADS)

    Sun, Cuicui; Li, Huanhuan; Koidis, Anastasios; Chen, Quansheng

    2016-08-01

    Rare earth doped upconversion nanoparticles convert near-infrared excitation light into visible emission light. Compared to organic fluorophores and semiconducting nanoparticles, upconversion nanoparticles (UCNPs) offer high photochemical stability, sharp emission bandwidths, and large anti-Stokes shifts. Along with the significant light penetration depth and the absence of autofluorescence in biological samples under infrared excitation, these UCNPs have attracted more and more attention on toxin detection and biological labelling. Herein, the fluorescence probe based on UCNPs was developed for quantifying Aflatoxin B1 (AFB1) in peanut oil. Based on a specific immunity format, the detection limit for AFB1 under optimal conditions was obtained as low as 0.2 ng·ml- 1, and in the effective detection range 0.2 to 100 ng·ml- 1, good relationship between fluorescence intensity and AFB1 concentration was achieved under the linear ratios up to 0.90. Moreover, to check the feasibility of these probes on AFB1 measurements in peanut oil, recovery tests have been carried out. A good accuracy rating (93.8%) was obtained in this study. Results showed that the nanoparticles can be successfully applied for sensing AFB1 in peanut oil.

  11. An attempt to model the probability of growth and aflatoxin B1 production of Aspergillus flavus under non-isothermal conditions in pistachio nuts.

    PubMed

    Aldars-García, Laila; Ramos, Antonio J; Sanchis, Vicente; Marín, Sonia

    2015-10-01

    Human exposure to aflatoxins in foods is of great concern. The aim of this work was to use predictive mycology as a strategy to mitigate the aflatoxin burden in pistachio nuts postharvest. The probability of growth and aflatoxin B1 (AFB1) production of aflatoxigenic Aspergillus flavus, isolated from pistachio nuts, under static and non-isothermal conditions was studied. Four theoretical temperature scenarios, including temperature levels observed in pistachio nuts during shipping and storage, were used. Two types of inoculum were included: a cocktail of 25 A. flavus isolates and a single isolate inoculum. Initial water activity was adjusted to 0.87. Logistic models, with temperature and time as explanatory variables, were fitted to the probability of growth and AFB1 production under a constant temperature. Subsequently, they were used to predict probabilities under non-isothermal scenarios, with levels of concordance from 90 to 100% in most of the cases. Furthermore, the presence of AFB1 in pistachio nuts could be correctly predicted in 70-81 % of the cases from a growth model developed in pistachio nuts, and in 67-81% of the cases from an AFB1 model developed in pistachio agar. The information obtained in the present work could be used by producers and processors to predict the time for AFB1 production by A. flavus on pistachio nuts during transport and storage.

  12. Zearalenone, deoxynivalenol and aflatoxin B1 and their metabolites in pig urine as biomarkers for mycotoxin exposure.

    PubMed

    Thieu, N Q; Pettersson, H

    2009-06-01

    Methods to determine zearalenone (ZEA), deoxynivalenol (DON), aflatoxins (AF) and their metabolites in pig urine were developed as biomarkers for pig exposure to the mycotoxins in feed. Urine samples were incubated with β-glucuronidase to cleave conjugates, extracted and cleaned-up with solid phase and immunoaffinity columns, followed by HPLC with UV and fluorescence detection. Good recoveries (83-130%), low variation (2-10%), and low detection limits (0.3-9.9 ng/ml) were obtained. The results of controlled AFB1 feeding trials found no difference in urine concentrations of AFB1 or AFM1 from pigs fed three different levels (127, 227, 327 µg/kg) of AFB1 in diets. The excretion of AFB1 and AFM1 in urine was on average 30% of the oral dose and the ratio AFB1 to AFM1 was around 23%. The analysis of 15 Vietnamese pig urine samples indicate a relatively high exposure of ZEA, DON and AF, which were found as toxin or metabolites in 47, 73, and 80% of the urine samples, respectively.

  13. An in vitro study of alkaline phosphatase sensitivity to mixture of aflatoxin B1 and fumonisin B1 in the hepatopancreas of coastal lagoon wild and farmed shrimp Litopenaeus vannamei.

    PubMed

    Pérez-Acosta, Jesús A; Burgos-Hernandez, Armando; Velázquez-Contreras, Carlos A; Márquez-Ríos, Enrique; Torres-Arreola, Wilfrido; Arvizu-Flores, Aldo A; Ezquerra-Brauer, J Marina

    2016-08-01

    This study aimed to establish the combined effect of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) on wild Litopenaeus vannamei hepatopancreas alkaline phosphatase (AP) activity compared with that of farmed shrimp. AP activity in hepatopancreas extract was confirmed by several specific inhibitor assays. AP activity of wild shrimp was higher than that of farmed shrimp (p < 0.05). However, AP activity from both wild and farmed shrimp was inhibited when incubated with AFB1 and FB1. The greatest inhibition occurred when AP was incubated with a mixture of AFB1 and FB1. The IC50 for AFB1 on AP activity of wild and farmed shrimp hepatopancreases was 0.790 and 0.398 μg/mL, respectively. The IC50 of FB1 was 0.87 μg/mL for wild shrimp and 0.69 μg/mL for farmed shrimp. These results suggest that, at the mycotoxins concentrations used in the study, AP from farmed L. vannamei was sensitive to the presence of both mycotoxins; however, AP is more sensitive to the combination of AFB1 + FB1 suggesting a possible synergistic or potentiating inhibitory effect.

  14. Molecular Mechanisms of Lipoic Acid Protection against Aflatoxin B1-Induced Liver Oxidative Damage and Inflammatory Responses in Broilers

    PubMed Central

    Ma, Qiugang; Li, Yan; Fan, Yu; Zhao, Lihong; Wei, Hua; Ji, Cheng; Zhang, Jianyun

    2015-01-01

    Alpha-lipoic acid (α-LA) was evaluated in this study for its molecular mechanisms against liver oxidative damage and inflammatory responses induced by aflatoxin B1 (AFB1). Birds were randomly allocated into four groups with different diets for three weeks: a basal diet, a 300 mg/kg α-LA supplementation in a basal diet, a diet containing 74 μg/kg AFB1, and 300 mg/kg α-LA supplementation in a diet containing 74 μg/kg AFB1. In the AFB1 group, the expression of GSH-PX mRNA was down-regulated (p < 0.05), and the levels of lipid peroxide and nitric oxide were increased (p < 0.05) in the chicken livers compared to those of the control group. Additionally, the mRNA level of the pro-inflammatory factor interleukin-6 was up-regulated significantly (p < 0.05), the protein expressions of both the nuclear factor kappa B (NF-κB) p65 and the inducible nitric oxide synthase were enhanced significantly (p < 0.05) in the AFB1 group. All of these negative effects were inhibited by α-LA. These results indicate that α-LA may be effective in preventing hepatic oxidative stress, down-regulating the expression of hepatic pro-inflammatory cytokines, as well as inhibiting NF-κB expression. PMID:26694462

  15. Detoxification of aflatoxin B1 by an aqueous extract from leaves of Adhatoda vasica Nees.

    PubMed

    Vijayanandraj, S; Brinda, R; Kannan, K; Adhithya, R; Vinothini, S; Senthil, K; Chinta, Ramakoteswara Rao; Paranidharan, V; Velazhahan, R

    2014-04-01

    The effectiveness of aqueous extracts of various medicinal plants in detoxification of aflatoxin B1 (AFB1) was tested in vitro by thin-layer chromatography and enzyme-linked immunosorbent assay (ELISA). Among the different plant extracts, the leaf extract of Vasaka (Adhatoda vasica Nees) showed the maximum degradation of AFB1 (≥ 98%) after incubation for 24h at 37 °C. The aflatoxin detoxifying activity of the A. vasica leaf extract was significantly reduced by heating to 100 °C for 10 min or autoclaving at 121 °C for 20 min. Dialysis had no effect on aflatoxin detoxifying ability of A. vasica extract and the dialyzed extract showed similar level of detoxification of AFB1 as that of the untreated extract. A time course study of aflatoxin detoxification by A. vasica extract showed that 69% of the toxin was degraded within 6h and ≥ 95% degradation was observed after 24h of incubation. Detoxification of AFB1 by A. vasica extract was further confirmed by liquid chromatography-mass spectrometry (LC-MS) analysis. Phytochemical analysis revealed the presence of alkaloids in methanolic extract of A. vasica leaves. A partially purified alkaloid from A. vasica leaves by preparative TLC exhibited strong AFB1 detoxification activity.

  16. Aflatoxin B1 binding to sorbents in bovine ruminal fluid.

    PubMed

    Spotti, M; Fracchiolla, M L; Arioli, F; Caloni, F; Pompa, G

    2005-08-01

    A recent approach to the problem of contamination of agricultural products by aflatoxin B(1) (AFB(1)) is to add non-nutritional adsorbents to animal diets in order to sequester ingested aflatoxins. We conducted in vitro experiments to develop a rapid and cheap model using ruminal fluid to assess the ability of sorbent materials to bind AFB(1). Seven sorbents (hydrated sodium calcium aluminosilicate; clinoptilolite; zeolite; two types of bentonite; sepiolite; and PHIL 75), commonly added to bovine diets were incubated in water and ruminal fluid in the presence of AFB(1). Hydrated sodium calcium aluminosilicate, sepiolite and one of the bentonites bound 100% of the AFB(1) in the presence of both ruminal fluid and water; clinoptilolite bound about 80% of AFB(1) in both liquids; whereas the affinities for the mycotoxin of zeolite (50%) and the other sample of bentonite (60%) in water seem to be increased by about 40% in ruminal fluid incubations. PHIL 75 had the poorest binding ability: about 30% in water and 45% in ruminal fluid. In view of the differences in toxin binding in water and ruminal fluid, it is preferable to use the ruminal fluid model for the in vitro pre-screening of sorbent materials potentially useful as adjuvants to ruminant feeds.

  17. Affinity improvement by fine tuning of single-chain variable fragment against aflatoxin B1.

    PubMed

    Min, Won-Ki; Na, Kang-In; Yoon, Jung-Hyun; Heo, Yoon-Jee; Lee, Daesang; Kim, Sung-Gun; Seo, Jin-Ho

    2016-10-15

    Aflatoxin B1 (AFB1) produced in Aspergillus flavus is a major hepatocarcinogen found in foods and feed. For effective immunological detection of AFB1 at low concentrations, the development of high affinity antibody for AFB1 is required. Previously, an affinity-maturated single-chain variable fragment containing 6 mutations (scFv-M37) was isolated from an artificial mutagenic library, which showed a 9-fold higher affinity than its wild type scFv. In this study, the effect of the 6 mutated residues on the affinity improvement was characterized using surface plasmon resonance analysis, which identified a deleterious mutation (VH-A110T) located on a framework region of the scFv-M37. The back mutation of VH-A110T resulted in a 3.2-fold affinity improvement, which was attributed to decrease of dissociation rate constant (kd) in interaction between AFB1 and the back mutant scFv. The biophysical analyses using circular dichroism and gel filtration revealed that the back mutation of VH-A110T caused a subtle conformational change of the scFv toward tighter binding to AFB1.

  18. Quantifying Aflatoxin B1 in peanut oil using fabricating fluorescence probes based on upconversion nanoparticles.

    PubMed

    Sun, Cuicui; Li, Huanhuan; Koidis, Anastasios; Chen, Quansheng

    2016-08-05

    Rare earth doped upconversion nanoparticles convert near-infrared excitation light into visible emission light. Compared to organic fluorophores and semiconducting nanoparticles, upconversion nanoparticles (UCNPs) offer high photochemical stability, sharp emission bandwidths, and large anti-Stokes shifts. Along with the significant light penetration depth and the absence of autofluorescence in biological samples under infrared excitation, these UCNPs have attracted more and more attention on toxin detection and biological labelling. Herein, the fluorescence probe based on UCNPs was developed for quantifying Aflatoxin B1 (AFB1) in peanut oil. Based on a specific immunity format, the detection limit for AFB1 under optimal conditions was obtained as low as 0.2ng·ml(-1), and in the effective detection range 0.2 to 100ng·ml(-1), good relationship between fluorescence intensity and AFB1 concentration was achieved under the linear ratios up to 0.90. Moreover, to check the feasibility of these probes on AFB1 measurements in peanut oil, recovery tests have been carried out. A good accuracy rating (93.8%) was obtained in this study. Results showed that the nanoparticles can be successfully applied for sensing AFB1 in peanut oil.

  19. Occurrence of aflatoxin B1 and ochratoxin A in dried vine fruits from Greek market.

    PubMed

    Kollia, Eleni; Kanapitsas, Alexandros; Markaki, Panagiota

    2014-01-01

    Twenty-six samples of dried vine fruits from Athens and Thebes (Central Greece) market were simultaneously extracted and cleaned up by immunoaffinity columns and analysed for aflatoxin B1 (AFB1) and ochratoxin A (OTA). A combination of ELISA and HPLC methods was applied for the determination of AFB1. Recovery was 97.6%, RSD 6.46%, while the limit of detection (LOD) and limit of quantification (LOQ) were 0.05 μg kg(-1) and 0.09 μg kg(-1), respectively. OTA concentrations were only estimated by ELISA. Results revealed the presence of AFB1 in 23% of the samples (mean 1.4 μg AFB1 kg(-1)), but none exceeded the EU limit (2 μg AFB1 kg(-1)). However, OTA was detected in 100% of the samples (mean 47.2 μg OTA kg(-1)). Six samples were found to be contaminated at high levels (median 120.6 μg OTA kg(-1)) and 18 exceeded the EU limit (10 μg OTA kg(-1)).

  20. Penetration of aflatoxins through isolated human epidermis

    SciTech Connect

    Riley, R.T.; Kemppainen, B.W.; Norred, W.P.

    1985-01-01

    The purpose of this study was to determine if aflatoxin B1 (AFB1) could penetrate through isolated human epidermis (stratum corneum plus viable epidermis). ( UC)AFB1 (7.5-9.3 micrograms) was applied to the stratum corneum of epidermal disks mounted in Teflon diffusion cells. ( UC)AFB1 penetrated chemically unaltered through the isolated epidermis. Chloroform-extractable radioactivity accounted for 82.5 +/- 3.7% of the total penetrating radioactivity in the receptor fluid of the diffusion cells. The rate of penetration was very slow when experiments were conducted under nonoccluded conditions, but was approximately 40 times greater under conditions of occlusion. Penetration after 46 h was less than 0.05% and 3.41% of the applied dose under nonoccluded and occluded conditions, respectively. Total recovery expressed as a percentage of the applied radioactivity was 98.6 +/- 6.4%.

  1. Multi-Toxic Endpoints of the Foodborne Mycotoxins in Nematode Caenorhabditis elegans

    PubMed Central

    Yang, Zhendong; Xue, Kathy S.; Sun, Xiulan; Tang, Lili; Wang, Jia-Sheng

    2015-01-01

    Aflatoxins B1 (AFB1), deoxynivalenol (DON), fumonisin B1 (FB1), T-2 toxin (T-2), and zearalenone (ZEA) are the major foodborne mycotoxins of public health concerns. In the present study, the multiple toxic endpoints of these naturally-occurring mycotoxins were evaluated in Caenorhabditis elegans model for their lethality, toxic effects on growth and reproduction, as well as influence on lifespan. We found that the lethality endpoint was more sensitive for T-2 toxicity with the EC50 at 1.38 mg/L, the growth endpoint was relatively sensitive for AFB1 toxic effects, and the reproduction endpoint was more sensitive for toxicities of AFB1, FB1, and ZEA. Moreover, the lifespan endpoint was sensitive to toxic effects of all five tested mycotoxins. Data obtained from this study may serve as an important contribution to knowledge on assessment of mycotoxin toxic effects, especially for assessing developmental and reproductive toxic effects, using the C. elegans model. PMID:26633509

  2. Generation of a New Model Rat: Nrf2 Knockout Rats Are Sensitive to Aflatoxin B1 Toxicity.

    PubMed

    Taguchi, Keiko; Takaku, Misaki; Egner, Patricia A; Morita, Masanobu; Kaneko, Takehito; Mashimo, Tomoji; Kensler, Thomas W; Yamamoto, Masayuki

    2016-07-01

    THE TRANSCRIPTION FACTOR NRF2: (NF-E2-related-factor 2) REGULATES A BATTERY OF ANTIOXIDATIVE STRESS-RESPONSE GENES AND DETOXICATION GENES, AND NRF2 KNOCKOUT LINES OF MICE HAVE BEEN CONTRIBUTING CRITICALLY TO THE CLARIFICATION OF ROLES THAT NRF2 PLAYS FOR CELL PROTECTION HOWEVER, THERE ARE APPARENT LIMITATIONS IN USE OF THE MOUSE MODELS FOR INSTANCE, RATS EXHIBIT MORE SUITABLE FEATURES FOR TOXICOLOGICAL OR PHYSIOLOGICAL EXAMINATIONS THAN MICE IN THIS STUDY, WE GENERATED 2 LINES OF NRF2 KNOCKOUT RATS BY USING A GENOME EDITING TECHNOLOGY; 1 LINE HARBORS A 7-BP DELETION Δ7 AND THE OTHER LINE HARBORS A 1-BP INSERTION +1 IN THE NRF2 GENE IN THE LIVERS OF RATS HOMOZYGOUSLY DELETING THE NRF2 GENE, AN ACTIVATOR OF NRF2 SIGNALING, CDDO-IM, COULD NOT INDUCE EXPRESSION OF REPRESENTATIVE NRF2 TARGET GENES TO EXAMINE ALTERED TOXICOLOGICAL RESPONSE, WE TREATED THE NRF2 KNOCKOUT RATS WITH AFLATOXIN B1 AFB1, A CARCINOGENIC MYCOTOXIN THAT ELICITS GENE MUTATIONS THROUGH BINDING OF ITS METABOLITES TO DNA AND FOR WHICH THE RAT HAS BEEN PROPOSED AS A REASONABLE SURROGATE FOR HUMAN TOXICITY INDEED, IN THE NRF2 KNOCKOUT RAT LIVERS THE ENZYMES OF THE AFB1 DETOXICATION PATHWAY WERE SIGNIFICANTLY DOWNREGULATED SINGLE DOSE ADMINISTRATION OF AFB1 INCREASED HEPATOTOXICITY AND BINDING OF AFB1-N7-GUANINE TO HEPATIC DNA IN NRF2 KNOCKOUT RATS COMPARED WITH WILD-TYPE NRF2 KNOCKOUT RATS REPEATEDLY TREATED WITH AFB1 WERE PRONE TO LETHALITY AND CDDO-IM WAS NO LONGER PROTECTIVE THESE RESULTS DEMONSTRATE THAT NRF2 KNOCKOUT RATS ARE QUITE SENSITIVE TO AFB1 TOXICITIES AND THIS RAT GENOTYPE EMERGES AS A NEW MODEL ANIMAL IN TOXICOLOGY.

  3. Aflatoxin B1 and clinoptilolite in feed for laying hens: effects on egg quality, mycotoxin residues in livers, and hepatic mixed-function oxygenase activities.

    PubMed

    Rizzi, L; Simioli, M; Roncada, P; Zaghini, A

    2003-05-01

    Ninety-six laying hens were allocated to four groups administered different diets (group 0-0 received a complete diet, group 0-AF received a diet supplemented with 2.5 ppm of aflatoxin B1 [AFB1], group 2-0 received a diet supplemented with 2% clinoptilolite [CPL], and group 2-AF received a diet supplemented with 2% CPL and 2.5 ppm of AFB1) for 4 weeks to evaluate the effect of AFBI and/or CPL on egg quality and the ability of CPL to interact with the oral administration of AFB1. The possible effects of AFB1 on cytochrome P450-dependent hepatic mixed-function oxygenase (MFO) activities were also evaluated. Mycotoxin reduced yolk weight, while CPL influenced albumen percentage relative to that of eggs laid by chickens in group 0-AF Eggs laid by chickens in groups 0-AF and 2-AF had stronger shells and weighed less than the eggs of other groups. The eggs of treated groups were lighter in color than those of the control group (P < 0.01), and the tendency to yellowness in eggs was increased by CPL, probably through the affinity of red pigments for adsorbents and a consequent prevalence of yellow tonality. Color parameters might be connected with AFB1's interference with lipid metabolism and pigment deposition. The livers of hens in groups 0-AF and 2-AF showed very low mycotoxin concentrations that were significantly different (P < 0.01). The highest levels observed were those in the livers of the hens receiving the diet supplemented with the mycotoxin alone. AFB1 did not exert any significant effects on the hepatic MFO activities examined.

  4. Protective role of bentonite against aflatoxin B1- and ochratoxin A-induced immunotoxicity in broilers.

    PubMed

    Bhatti, Sheraz Ahmed; Khan, Muhammad Zargham; Saleemi, Muhammad Kashif; Saqib, Muhammad; Khan, Ahrar; Ul-Hassan, Zahoor

    2017-12-01

    The present study was designed to investigate any ameliorative effects of bentonite (BN) against immuno-pathological alterations induced by dietary aflatoxin B1 (AFB1) or ochratoxin A (OTA) in broiler chicks. In one experiment, AFB1 (0.1, 0.2 or 0.6 mg/kg feed) was fed alone and par alley with bentonite clay (3.7 or 7.5 g/kg feed) to the broilers. In the second experiment, the broilers were given feed contaminated with OTA (0.15, 0.3 or 1.0 mg/kg feed) alone and in combination with bentonite clay (3.7, 7.5, or 15 g/kg feed). Experimental feedings were continued for 42 days. At various time points along the feeding schedule, immune system organ histologic status, as well as host humoral and cellular immune responses, were evaluated in all groups. The dietary addition of AFB1 and OTA alone significantly reduced immune responses in the birds as assessed by histological changes in the bursa of Fabricius and thymus, antibody responses to SRBC, in-vivo lympho-proliferative responses to Phytohemagglutinin-P (PHA-P) and, phagocytic function in situ. The dietary addition of BN significantly ameliorated the immunotoxicity of 0.1 and 0.2 mg/kg dietary AFB1, however with a level of 0.6 mg AFB1/kg only partial amelioration was seen. The co-treatment of birds exposed to OTA with BN at all levels only partially alleviated deleterious effects on histology and immune responses. Taken together, the results here suggested to us that dietary addition of BN could help ameliorate AFB1-mediated immunotoxicities but could not afford such protection against OTA-induced immune damage.

  5. In vitro ability of beer fermentation residue and yeast-based products to bind aflatoxin B1.

    PubMed

    Bovo, Fernanda; Franco, Larissa Tuanny; Rosim, Roice Eliana; Barbalho, Ricardo; de Oliveira, Carlos Augusto Fernandes

    2015-06-01

    This study aimed to verify the in vitro ability of beer fermentation residue (BFR) containing Saccharomyces cerevisiae cells and five commercial products that differed in the viability and integrity of S. cerevisiae cells to remove aflatoxin B1 (AFB1) from a citrate-phosphate buffer solution (CPBS). BFR was collected at a microbrewery and prepared by drying and milling. The commercial yeast-based products were as follows: inactive intact yeast cells from beer alcoholic fermentation, inactive intact yeast cells from sugarcane alcoholic fermentation, hydrolyzed yeast cells, yeast cell walls and active yeast cells. Adsorption assays were performed in CPBS spiked with 1.0 μg AFB1/mL at pH 3.0 and 6.0 for a contact time of 60 min at room temperature. Analysis of AFB1 in the samples was performed by high performance liquid chromatography. AFB1 adsorption by the products ranged from 45.5% to 69.4% at pH 3.0 and from 24.0% to 63.8% at pH 6.0. The higher percentages (p < 0.05) of AFB1 binding at both pH values were achieved with products containing hydrolyzed yeast cells or yeast cell walls rather than intact cells. The AFB1 binding percentages of BFR were 55.0 ± 5.0% at pH 3.0 and 49.2 ± 4.5% at pH 6.0, which was not significantly different (p > 0.05) from commercial products containing inactive intact yeast cells. The results of this trial indicate that the yeast-based products tested, especially the BFR, have potential applications in animal feeds as a suitable biological method for reducing the adverse effects of aflatoxins.

  6. Detoxification and antioxidant effects of garlic and curcumin in Oreochromis niloticus injected with aflatoxin B₁ with reference to gene expression of glutathione peroxidase (GPx) by RT-PCR.

    PubMed

    El-Barbary, Manal I

    2016-04-01

    The present study aims to investigate the effects of both garlic and curcumin through evaluating their therapeutic properties as antioxidants on liver and kidney functions, hepatic antioxidants and GPx gene expression against aflatoxicosis of O. niloticus. In total, 180 of tilapia were divided into ten groups; T1 represented the negative control fed on a basal diet, and T2 was injected with a single intraperitoneal (i.p.) dose of AFB1 (6 mg/kg b.w.). Fish in T3-T6 were fed on a basal diet supplemented with both garlic (T3 and T4) and curcumin (T5 and T6) at the two concentrations of 10 and 20 g/kg diet, respectively. Fish in T7-T10 groups were injected with AFB1 and fed on the garlic (T7 and T8) and curcumin (T9 and T10) dietaries. The results showed that AFB1 has significant potency for increasing the activity of plasma AST, ALT, creatinine and uric acid values, and hepatic MDA as well as for reducing the concentrations of plasma TP, AL, GL and hepatic activity of TAC, while AFB1 led to up-regulated GPx gene expression when compared to the control (T1). These harmful effects of AFB1 were alleviated due to the garlic and curcumin dietaries in some studied parameters. Garlic reflected the highest induction of gene expression (T7); however, curcumin showed significant down-regulated (T9). These results concluded that the effects of garlic were better than curcumin at the two concentrations and the low concentration of them is more beneficial than the high concentration when it used against AFB1 in O. niloticus.

  7. Synergistic effect of black tea and curcumin in improving the hepatotoxicity induced by aflatoxin B1 in rats.

    PubMed

    Alm-Eldeen, Abeer A; Mona, Mohamed H; Shati, Ali A; El-Mekkawy, Haitham I

    2015-12-01

    Aflatoxin B1 (AFB1) is a toxic compound commonly found as a contaminant in human food. It is carcinogenic due its potential in inducing the oxidative stress and distortion of the most antioxidant enzymes. Since black tea possesses strong antioxidant activity, it protects cells and tissues against oxidative stress. Curcumin (CMN), a naturally occurring agent, has a combination of biological and pharmacological properties that include antioxidant activity. Therefore, the present study was carried out to investigate the possible role of separate and mixed supplementation of black tea extract and CMN in the hepatotoxicity induced by AFB1 in rats. A total of 48: adult male Sprague Dawley rats were randomly divided into eight groups with six rats in each group. Group 1 (normal control) includes rats that received no treatment. Groups 2, 3, and 4 (positive control) include rats that received olive oil, black tea extract, and CMN, respectively. Group 5 includes rats that received AFB1 at a dose of 750 μg/kg body weight (b.w.) dissolved in olive oil. Groups 6, 7, and 8 include rats that received AFB1 along with 2% black tea extract, CMN at a dose of 200 mg/kg b.w., and both black tea extract and CMN at the same previous doses, respectively. After 90 days, biochemical and histopathological examination was carried out for the blood samples and liver tissues. A significant decrease in the antioxidant enzymes and a significant increase in the lipid peroxidation and hydrogen peroxide in the rats treated with AFB1 were observed. Moreover, there were dramatic changes in the liver function biomarkers, lipid profile, and liver architecture. Supplementation of black tea extract or CMN showed an efficient role in repairing the distortion of the biochemical and histological changes induced by AFB1 in liver. This improvement was more pronounced when both CMN and black tea were used together.

  8. Aflatoxin-albumin adduct formation after single and multiple doses of aflatoxin B(1) in rats treated with Thai medicinal plants.

    PubMed

    Vinitketkumnuen, U; Chewonarin, T; Dhumtanom, P; Lertprasertsuk, N; Wild, C P

    1999-07-16

    The objective was to conduct an assessment of the ability of two Thai medicinal plants, Cymbopogon citratus Stapf and Murdannia loriformis, to modulate levels of serum aflatoxin-albumin (AF-albumin) adducts following aflatoxin B(1) (AFB(1)) exposure in rats. The influence of the plant extracts on AF-albumin adduct formation after a single exposure to 250 microg/kg body weight (bw) AFB(1) was measured over a 48-h period. Rats received M. loriformis extract (3 g/kg bw) or C. citratus Stapf extract (5 g/kg bw) daily for the week prior to the AFB(1) administration. In control rats, maximum adduct levels were observed 12 h post-AFB(1) treatment but in the animals receiving Murdannia extract, maximum levels occurred earlier, at 4 h post-treatment. No such effect was observed with the Cymbopogon extract. Daily treatment of rats with AFB(1) at 250 microg/kg bw for 3 weeks caused serum AF-albumin adduct levels to accumulate over a 10-14 day period and reach plateau levels 4.4-fold higher than observed after a single dose. Treatment with Murdannia extract for 1 week before and then throughout the AFB(1) exposure period resulted in a slight decrease in the AF-albumin adduct levels in the first week of the intervention. After that time, however, the reduction in adduct levels in the Murdannia extract group did not differ significantly from controls. No significant alteration in the biomarker levels was seen with the Cymbopogon extract treatments compared to control rats.

  9. Effects of aflatoxin B1 and fumonisin B1 on body weight, antibody titres and histology of broiler chicks.

    PubMed

    Tessari, E N C; Oliveira, C A F; Cardoso, A L S P; Ledoux, D R; Rottinghaus, G E

    2006-06-01

    1. Our objective was to evaluate the toxic effects of aflatoxin B1 (AFB1) and fumonisin B1 (FB1), administered singly or in combination to broilers. 2. Feeds were prepared with concentrations equal to 0, 50 and 200 microg AFB1/kg, and/or 0, 50 and 200 mg FB1/kg, and offered to broiler chicks from 8 to 41 d of age. The experimental design was totally randomised, in a 3 x 3 factorial arrangement with 9 treatments and 12 birds per treatment. Animals were vaccinated against Newcastle disease on d 14 of life and killed at 41 d. 3. Compared with controls, all mycotoxin-treated groups at 41 d had lower body weight and weight gain, and higher relative heart weight. The relative weight of the liver increased only in birds fed diets containing 200 mg FB1, singly or in combination with AFB1. 4. At 35 d, all groups receiving mycotoxin-treated rations had reduced geometrical mean antibody titres, with birds from groups fed combinations of AFB1 and FB1/kg having even lower values, when compared to the other groups. 5. Histological changes were observed only in liver from birds fed mycotoxin-contaminated rations, and in kidneys of birds fed the diet containing 200 microg AFB1 and 200 mg FB1/kg. Main alterations included vacuolar degeneration and cell proliferation of bile ducts in the liver, and hydropic degeneration in renal tubules in the kidneys. 6. We concluded that AFB1 and FB1 in combination have primarily additive effects on body weight, liver structure and immunological response of broilers at the concentrations used.

  10. Involvement of cytochrome P450, glutathione S-transferase, and epoxide hydrolase in the metabolism of aflatoxin B1 and relevance to risk of human liver cancer.

    PubMed Central

    Guengerich, F P; Johnson, W W; Ueng, Y F; Yamazaki, H; Shimada, T

    1996-01-01

    In recent years there has been considerable interest in the effect of variations in activities of xenobiotic-metabolizing enzymes on cancer incidence. This interest has accelerated with the development of methods for analyzing genetic polymorphisms. However, progress in epidemiology has been slow and the contributions of polymorphisms to risks from individual chemicals and mixtures are often controversial. A series of studies is presented to show the complexities encountered with a single chemical, aflatoxin B1 (AFB1). AFB1 is oxidized by human cytochrome P450 enzymes to several products. Only one of these, the 8,9-exo-epoxide, appears to be mutagenic and the others are detoxication products. P450 3A4, which can both activate and detoxicate AFB1, is found in the liver and the small intestine. In the small intestine, the first contact after oral exposure, epoxidation would not lead to liver cancer. The (nonenzymatic) half-life of the epoxide has been determined to be approximately 1 sec at 23 degrees C and neutral pH. Although the half-life is short, AFB1-8,9-exo-epoxide does react with DNA and glutathione S-transferase. Levels of these conjugates have been measured and combined with the rate of hydrolysis in a kinetic model to predict constants for binding of the epoxide with DNA and glutathione S-transferase. A role for epoxide hydrolase in alteration of AFB1 hepatocarcinogenesis has been proposed, although experimental evidence is lacking. Some inhibition of microsome-generated genotoxicity was observed with rat epoxide hydrolase; further information on the extent of contribution of this enzyme to AFB1 metabolism is not yet available. PMID:8781383

  11. Prenatal exposure of mice to the human liver carcinogen aflatoxin B1 reveals a critical window of susceptibility to genetic change.

    PubMed

    Chawanthayatham, Supawadee; Thiantanawat, Apinya; Egner, Patricia A; Groopman, John D; Wogan, Gerald N; Croy, Robert G; Essigmann, John M

    2015-03-15

    It has become axiomatic that critical windows of susceptibility to genotoxins exist and that genetic damage in utero may be a trigger for later life cancers. Data supporting this critical window hypothesis are remarkably few. This study provides a quantitative bridge between DNA damage by the liver carcinogen aflatoxin B1 (AFB1 ) during prenatal development and the risk of later life genetic disease. AFB1 was given to pregnant C57BL/6J mice, carrying F1 gestation day 14 (GD14) embryos of the B6C3F1 genotype. Ultra-high performance liquid chromatography and mass spectrometry (UPLC-MS) using aflatoxin-(15) N5 -guanine adduct standards afforded measurement of the AFB1 -N(7) -Gua and AFB1 -FAPY adducts 6-hr post dosing in liver DNA of mothers and embryos. A parallel cohort gave birth and the livers of the F1 were analyzed for mutations in the gpt gene at 3 and 10 weeks of age. The data revealed mutational spectra dominated by G:C to T:A mutations in both the mother and offspring that are characteristic of AFB1 and distinct from background. It was shown that adducts in GD14 embryos were 20-fold more potent inducers of mutagenesis than adducts in parallel-dosed adults. This sensitivity enhancement correlated with Ki67 staining of the liver, reflecting the proliferative potential of the tissue. Taken together, these data provide insight into the relative genetic risks of prenatal and adult exposures to AFB1 . Early life exposure, especially during the embryonic period, is strikingly more mutagenic than treatment later in life. Moreover the data provide a baseline against which risk prevention strategies can be evaluated.

  12. In vitro ability of beer fermentation residue and yeast-based products to bind aflatoxin B1

    PubMed Central

    Bovo, Fernanda; Franco, Larissa Tuanny; Rosim, Roice Eliana; Barbalho, Ricardo; de Oliveira, Carlos Augusto Fernandes

    2015-01-01

    This study aimed to verify the in vitro ability of beer fermentation residue (BFR) containing Saccharomyces cerevisiae cells and five commercial products that differed in the viability and integrity of S. cerevisiae cells to remove aflatoxin B1 (AFB1) from a citrate-phosphate buffer solution (CPBS). BFR was collected at a microbrewery and prepared by drying and milling. The commercial yeast-based products were as follows: inactive intact yeast cells from beer alcoholic fermentation, inactive intact yeast cells from sugarcane alcoholic fermentation, hydrolyzed yeast cells, yeast cell walls and active yeast cells. Adsorption assays were performed in CPBS spiked with 1.0 μg AFB1/mL at pH 3.0 and 6.0 for a contact time of 60 min at room temperature. Analysis of AFB1 in the samples was performed by high performance liquid chromatography. AFB1 adsorption by the products ranged from 45.5% to 69.4% at pH 3.0 and from 24.0% to 63.8% at pH 6.0. The higher percentages (p < 0.05) of AFB1 binding at both pH values were achieved with products containing hydrolyzed yeast cells or yeast cell walls rather than intact cells. The AFB1 binding percentages of BFR were 55.0 ± 5.0% at pH 3.0 and 49.2 ± 4.5% at pH 6.0, which was not significantly different (p > 0.05) from commercial products containing inactive intact yeast cells. The results of this trial indicate that the yeast-based products tested, especially the BFR, have potential applications in animal feeds as a suitable biological method for reducing the adverse effects of aflatoxins. PMID:26273277

  13. The generalization of Plackett-Burman design based on fractional calculus of complex order

    NASA Astrophysics Data System (ADS)

    Ibrahim, Rabha W.; Jalab, Hamid A.

    2014-12-01

    Response surface attitude was working to optimize the degradation situations of Aflatoxin B1(AFB1) by Rhodococcus erythropolis in liquid culture. The interesting factors that influence the degradation, as identified by a Plackett-Burman design with six variables, were temperature, liquid volume, pH, inoculums size, agitation speed and incubation time. In this work, we generalize the Plackett-Burman design, based on fractional calculus of complex order, to describe correlation between the six variables and the degradation rate of AFB1. The experimental results show the influence of the proposed method. The results demonstrated that the degradation efficiency of R. erythropolis could extent 99% in liquid culture.

  14. Electrophoretically deposited reduced graphene oxide platform for food toxin detection

    NASA Astrophysics Data System (ADS)

    Srivastava, Saurabh; Kumar, Vinod; Ali, Md Azahar; Solanki, Pratima R.; Srivastava, Anchal; Sumana, Gajjala; Saxena, Preeti Suman; Joshi, Amish G.; Malhotra, B. D.

    2013-03-01

    Reduced graphene oxide (RGO) due to its excellent electrochemical properties and large surface area, has recently aroused much interest for electrochemical biosensing application. Here, the chemically active RGO has been synthesized and deposited onto an indium tin oxide (ITO) coated glass substrate by the electrophoretic deposition technique. This novel platform has been utilized for covalent attachment of the monoclonal antibodies of aflatoxin B1 (anti-AFB1) for food toxin (AFB1) detection. The electron microscopy, X-ray diffraction, and UV-visible studies reveal successful synthesis of reduced graphene oxide while the XPS and FTIR studies suggest its carboxylic functionalized nature. The electrochemical sensing results of the anti-AFB1/RGO/ITO based immunoelectrode obtained as a function of aflatoxin concentration show high sensitivity (68 μA ng-1 mL cm-2) and improved detection limit (0.12 ng mL-1). The association constant (ka) for antigen-antibody interaction obtained as 5 × 10-4 ng mL-1 indicates high affinity of antibodies toward the antigen (AFB1).Reduced graphene oxide (RGO) due to its excellent electrochemical properties and large surface area, has recently aroused much interest for electrochemical biosensing application. Here, the chemically active RGO has been synthesized and deposited onto an indium tin oxide (ITO) coated glass substrate by the electrophoretic deposition technique. This novel platform has been utilized for covalent attachment of the monoclonal antibodies of aflatoxin B1 (anti-AFB1) for food toxin (AFB1) detection. The electron microscopy, X-ray diffraction, and UV-visible studies reveal successful synthesis of reduced graphene oxide while the XPS and FTIR studies suggest its carboxylic functionalized nature. The electrochemical sensing results of the anti-AFB1/RGO/ITO based immunoelectrode obtained as a function of aflatoxin concentration show high sensitivity (68 μA ng-1 mL cm-2) and improved detection limit (0.12 ng mL-1). The

  15. Leaky Gut and Mycotoxins: Aflatoxin B1 Does Not Increase Gut Permeability in Broiler Chickens

    PubMed Central

    Galarza-Seeber, Rosario; Latorre, Juan D.; Bielke, Lisa R.; Kuttappan, Vivek A.; Wolfenden, Amanda D.; Hernandez-Velasco, Xochitl; Merino-Guzman, Ruben; Vicente, Jose L.; Donoghue, Annie; Cross, David; Hargis, Billy M.; Tellez, Guillermo

    2016-01-01

    Previous studies conducted in our laboratory have demonstrated that intestinal barrier function can be adversely affected by diet ingredients or feed restriction, resulting in increased intestinal inflammation-associated permeability. Two experiments were conducted in broilers to evaluate the effect of three concentrations of Aflatoxin B1 (AFB1; 2, 1.5, or 1 ppm) on gastrointestinal leakage and liver bacterial translocation (BT). In experiment 1, 240 day-of-hatch male broilers were allocated in two groups, each group had six replicates of 20 chickens (n = 120/group): Control feed or feed + 2 ppm AFB1. In experiment 2, 240 day-of-hatch male broilers were allocated in three groups, each group had five replicates of 16 chickens (n = 80/group): Control feed; feed + 1 ppm AFB1; or feed + 1.5 ppm AFB1. In both experiments, chickens were fed starter (days 1–7) and grower diets (days 8–21) ad libitum and performance parameters were evaluated every week. At day 21, all chicks received an oral gavage dose of FITC-d (4.16 mg/kg) 2.5 h before collecting blood samples to evaluate gastrointestinal leakage of FITC-d. In experiment 2, a hematologic analysis was also performed. Liver sections were aseptically collected and cultured using TSA plates to determine BT. Cecal contents were collected to determine total colony-forming units per gram of Gram-negative bacteria, lactic acid bacteria (LAB), or anaerobes by plating on selective media. In experiment 2, liver, spleen, and bursa of Fabricius were removed to determine organ weight ratio, and also intestinal samples were obtained for morphometric analysis. Performance parameters, organ weight ratio, and morphometric measurements were significantly different between Control and AFB1 groups in both experiments. Gut leakage of FITC-d was not affected by the three concentrations of AFB1 evaluated (P > 0.05). Interestingly, a significant reduction in BT was observed in chickens that received 2 and

  16. Prenatal exposure to aflatoxin B1: developmental, behavioral, and reproductive alterations in male rats

    NASA Astrophysics Data System (ADS)

    Supriya, Ch.; Reddy, P. Sreenivasula

    2015-06-01

    Previous studies have shown that aflatoxin B1 (AfB1) inhibits androgen biosynthesis as a result of its ability to form a high-affinity complex with the steroidogenic acute regulatory protein. The results of the present study demonstrate the postnatal effects of in utero exposure to AfB1 in the rat. Pregnant Wistar rats were given 10, 20, or 50 μg AfB1/kg body weight daily from gestation day (GD) 12 to GD 19. At parturition, newborns were observed for clinical signs and survival. All animals were born alive and initially appeared to be active. Male pups from control and AfB1-exposed animals were weaned and maintained up to postnatal day (PD) 100. Litter size, birth weight, sex ratio, survival rate, and crown-rump length of the pups were significantly decreased in AfB1-exposed rats when compared to controls. Elapsed time (days) for testes to descend into the scrotal sac was significantly delayed in experimental pups when compared to control pups. Behavioral observations such as cliff avoidance, negative geotaxis, surface rightening activity, ascending wire mesh, open field behavior, and exploratory and locomotory activities were significantly impaired in experimental pups. Body weights and the indices of testis, cauda epididymis, prostate, seminal vesicles, and liver were significantly reduced on PD 100 in male rats exposed to AfB1 during embryonic development when compared with controls. Significant reduction in the testicular daily sperm production, epididymal sperm count, and number of viable, motile, and hypo-osmotic tail coiled sperm was observed in experimental rats. The levels of serum testosterone and activity levels of testicular hydroxysteroid dehydrogenases were significantly decreased in a dose-dependent manner with a significant increase in the serum follicle-stimulating hormone and luteinizing hormone in experimental rats. Deterioration in the testicular and cauda epididymal architecture was observed in experimental rats. The results of fertility studies revealed a significant decrease in the mating index in experimental rats with an increase in the pre- and post-implantation losses in rats mated with prenatal AfB1-exposed males, indicating poor male reproductive performance. These results indicate that in utero exposure to AfB1 severely compromised postnatal development of neonatal rats, and caused a delay in testes descent and reduction in steroidogenesis and spermatogenesis that were accomplished by suppressed reproduction at adulthood.

  17. Identification of aflatoxin M1-N7-guanine in liver and urine of tree shrews and rats following administration of aflatoxin B1.

    PubMed

    Egner, Patricia A; Yu, Xiang; Johnson, Jesse K; Nathasingh, Christopher K; Groopman, John D; Kensler, Thomas W; Roebuck, Bill D

    2003-09-01

    Epidemiological studies have shown that exposure to aflatoxin B(1) (AFB(1)) and concurrent infection with hepatitis B lead to a multiplicative risk of developing liver cancer. This chemical-viral interaction can be recapitulated in the tree shrew (Tupia belangeri chinensis). As an initial characterization of this model, the metabolism of AFB(1) in tree shrews has been examined and compared to a sensitive bioassay species, the rat. Utilizing LC/MS/MS, an unreported product, aflatoxin M(1)-N(7)-guanine (AFM(1)-N(7)-guanine), was detected in urine and hepatic DNA samples 24 h after administration of 400 microg/kg AFB(1). In hepatic DNA isolated from tree shrews, AFM(1)-N(7)-guanine was the predominant adduct, 0.74 +/- 0.14 pmol/mg DNA, as compared to 0.37 +/- 0.07 pmol/mg DNA of AFB(1)-N(7)-guanine. Conversely, in rat liver, 6.56 +/- 2.41 pmol/mg DNA of AFB(1)-N(7)-guanine and 0.42 +/- 0.13 pmol/mg DNA of AFM(1)-N(7)-guanine were detected. Rats excreted 1.00 +/- 0.21 pmol AFB(1)-N(7)-guanine/mg creatinine and 0.29 +/- 0.10 pmol AFM(1)-N(7)-guanine/mg creatinine as compared to 0.60 +/- 0.12 pmol AFB(1)-N(7)-guanine/mg creatinine and 0.69 +/- 0.16 pmol AFM(1)-N(7)-guanine/mg creatinine excreted by the tree shrew. Furthermore, tree shrew urine contained 40 times more of the hydroxylated metabolite, AFM(1), than was excreted by rats. In vitro experiments confirmed this difference in oxidative metabolism. Hepatic microsomes isolated from tree shrews failed to produce aflatoxin Q(1) or aflatoxin P(1) but formed a significantly greater amount of AFM(1) than rat microsomes. Bioassays indicated that the tree shrew was considerably more resistant than the rat to AFB(1) hepatocarcinogenesis, which may reflect the significant differences in metabolic profiles of the two species.

  18. Ultrasensitive food toxin biosensor using frequency based signals of silicon oxide nanoporous structure

    NASA Astrophysics Data System (ADS)

    Ghosh, H.; RoyChaudhuri, C.

    2013-06-01

    We report an electrochemically fabricated silicon oxide nanoporous structure for ultrasensitive detection of AfB1 in food by shift in peak frequency corresponding to maximum sensitivity. It has been observed that the impedance sensitivity changes from 19% to 40% (which is only twice) where as the peak frequency shifts from 500 Hz to 50 kHz, for a change in concentration from 1 fg/ml to 1 pg/ml. This has been attributed to the combined effect of the significant pore narrowing with increasing AfB1 concentration and the opposing nature of impedance change within the nanopores and the conducting substrate immediately below the nanoporous layer.

  19. Mechanisms of Mycotoxin-induced Dermal Toxicity and Tumorigenesis Through Oxidative Stress-related Pathways

    PubMed Central

    Doi, Kunio; Uetsuka, Koji

    2014-01-01

    Among the many mycotoxins, T-2 toxin, citrinin (CTN), patulin (PAT), aflatoxin B1 (AFB1) and ochratoxin A (OTA) are known to have the potential to induce dermal toxicity and/or tumorigenesis in rodent models. T-2 toxin, CTN, PAT and OTA induce apoptosis in mouse or rat skin. PAT, AFB1 and OTA have tumor initiating properties, and OTA is also a tumor promoter in mouse skin. This paper reviews the molecular mechanisms of dermal toxicity and tumorigenesis induced in rodent models by these mycotoxins especially from the viewpoint of oxidative stress-mediated pathways. PMID:24791061

  20. Leaky Gut and Mycotoxins: Aflatoxin B1 Does Not Increase Gut Permeability in Broiler Chickens.

    PubMed

    Galarza-Seeber, Rosario; Latorre, Juan D; Bielke, Lisa R; Kuttappan, Vivek A; Wolfenden, Amanda D; Hernandez-Velasco, Xochitl; Merino-Guzman, Ruben; Vicente, Jose L; Donoghue, Annie; Cross, David; Hargis, Billy M; Tellez, Guillermo

    2016-01-01

    Previous studies conducted in our laboratory have demonstrated that intestinal barrier function can be adversely affected by diet ingredients or feed restriction, resulting in increased intestinal inflammation-associated permeability. Two experiments were conducted in broilers to evaluate the effect of three concentrations of Aflatoxin B1 (AFB1; 2, 1.5, or 1 ppm) on gastrointestinal leakage and liver bacterial translocation (BT). In experiment 1, 240 day-of-hatch male broilers were allocated in two groups, each group had six replicates of 20 chickens (n = 120/group): Control feed or feed + 2 ppm AFB1. In experiment 2, 240 day-of-hatch male broilers were allocated in three groups, each group had five replicates of 16 chickens (n = 80/group): Control feed; feed + 1 ppm AFB1; or feed + 1.5 ppm AFB1. In both experiments, chickens were fed starter (days 1-7) and grower diets (days 8-21) ad libitum and performance parameters were evaluated every week. At day 21, all chicks received an oral gavage dose of FITC-d (4.16 mg/kg) 2.5 h before collecting blood samples to evaluate gastrointestinal leakage of FITC-d. In experiment 2, a hematologic analysis was also performed. Liver sections were aseptically collected and cultured using TSA plates to determine BT. Cecal contents were collected to determine total colony-forming units per gram of Gram-negative bacteria, lactic acid bacteria (LAB), or anaerobes by plating on selective media. In experiment 2, liver, spleen, and bursa of Fabricius were removed to determine organ weight ratio, and also intestinal samples were obtained for morphometric analysis. Performance parameters, organ weight ratio, and morphometric measurements were significantly different between Control and AFB1 groups in both experiments. Gut leakage of FITC-d was not affected by the three concentrations of AFB1 evaluated (P > 0.05). Interestingly, a significant reduction in BT was observed in chickens that received 2 and 1

  1. Effects of Aflatoxin B1 and Fumonisin B1 on the Viability and Induction of Apoptosis in Rat Primary Hepatocytes

    PubMed Central

    Ribeiro, Deise H. B.; Ferreira, Fabiane L.; da Silva, Valéria N.; Aquino, Simone; Corrêa, Benedito

    2010-01-01

    The present study evaluated the effect of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) either alone, or in association, on rat primary hepatocyte cultures. Cell viability was assessed by flow cytometry after propidium iodine intercalation. DNA fragmentation and apoptosis were assessed by agarose gel electrophoresis and acridine orange and ethidium bromide staining. At the concentrations of AFB1 and FB1 used, the toxins did not decrease cell viability, but did induce apoptosis in a concentration and time-dependent manner. PMID:20480051

  2. RNA-Seq profiling reveals novel hepatic gene expression pattern in aflatoxin B1 treated rats.

    PubMed

    Merrick, B Alex; Phadke, Dhiral P; Auerbach, Scott S; Mav, Deepak; Stiegelmeyer, Suzy M; Shah, Ruchir R; Tice, Raymond R

    2013-01-01

    Deep sequencing was used to investigate the subchronic effects of 1 ppm aflatoxin B1 (AFB1), a potent hepatocarcinogen, on the male rat liver transcriptome prior to onset of histopathological lesions or tumors. We hypothesized RNA-Seq would reveal more differentially expressed genes (DEG) than microarray analysis, including low copy and novel transcripts related to AFB1's carcinogenic activity compared to feed controls (CTRL). Paired-end reads were mapped to the rat genome (Rn4) with TopHat and further analyzed by DESeq and Cufflinks-Cuffdiff pipelines to identify differentially expressed transcripts, new exons and unannotated transcripts. PCA and cluster analysis of DEGs showed clear separation between AFB1 and CTRL treatments and concordance among group replicates. qPCR of eight high and medium DEGs and three low DEGs showed good comparability among RNA-Seq and microarray transcripts. DESeq analysis identified 1,026 differentially expressed transcripts at greater than two-fold change (p<0.005) compared to 626 transcripts by microarray due to base pair resolution of transcripts by RNA-Seq, probe placement within transcripts or an absence of probes to detect novel transcripts, splice variants and exons. Pathway analysis among DEGs revealed signaling of Ahr, Nrf2, GSH, xenobiotic, cell cycle, extracellular matrix, and cell differentiation networks consistent with pathways leading to AFB1 carcinogenesis, including almost 200 upregulated transcripts controlled by E2f1-related pathways related to kinetochore structure, mitotic spindle assembly and tissue remodeling. We report 49 novel, differentially-expressed transcripts including confirmation by PCR-cloning of two unique, unannotated, hepatic AFB1-responsive transcripts (HAfT's) on chromosomes 1.q55 and 15.q11, overexpressed by 10 to 25-fold. Several potentially novel exons were found and exon refinements were made including AFB1 exon-specific induction of homologous family members, Ugt1a6 and Ugt1a7c. We find the

  3. Effect of melatonin on the production of microsomal hydrogen peroxide and cytochrome P-450 content in rat treated with aflatoxin B(1).

    PubMed

    Awney, Hala A; Attih, Ahmed M; Habib, Sami L; Mostafa, Mostafa H

    2002-03-20

    Aflatoxin B(1) (AFB(1)) is a food contaminant fungal toxin that has been implicated as a causative agent in human hepatic and extrahepatic carcinogenesis. In this study we went on to show the effect of melatonin as a free radical scavenger on the production of microsomal hydrogen peroxide (H(2)O(2)) during the metabolic activation AFB(1). The production of microsomal H(2)O(2) in vitro during the metabolic activation of different chemical carcinogens has been reported previously. We also studied the effect of melatonin on the cytochrome P-450 content as a major microsomal monooxygenase isoenzymes system in rat liver responsible for the metabolic activation of AFB(1). The amounts of H(2)O(2) and cytochrome P-450 contents in rat treated with melatonin (0.2 mg/kg BW) and/or AFB(1) (0.2 mg/kg BW) at various time intervals has been measured. Animals treated with melatonin exhibited markedly inhibition in the amounts of H(2)O(2) after 1, 3, and 6 h. The highest level of inhibition (3.0 nmol H(2)O(2)/mg protein) was detected after 6 h. However, cytochrome P-450 contents were also decreased after the same period of time. The highest level of inhibition (2.1 nmol/mg protein) was detected after 3 h of injection. A pronounced augmentation of H(2)O(2) production was observed in rat treated with AFB(1) only. The highest level of H(2)O(2) (100 nmol/mg protein) was measured after 1 h. Cytochrome P-450 contents were also decreased in response to AFB(1) injection over the same time intervals. Contrary data was detected in animals received both AFB(1) and melatonin. The generation of H(2)O(2) was inhibited by melatonin after 1, 3 and 6 h. The highest level of inhibition (44.2 nmol/mg protein) was observed after 6 h. Finally, these data suggested that melatonin as a free radical scavenger inhibited the microsomal production of H(2)O(2) in rat treated with AFB(1).

  4. Identification of early target genes of aflatoxin B1 in human hepatocytes, inter-individual variability and comparison with other genotoxic compounds

    SciTech Connect

    Josse, Rozenn; Dumont, Julie; Fautrel, Alain; Robin, Marie-Anne; Guillouzo, André

    2012-01-15

    Gene expression profiling has recently emerged as a promising approach to identify early target genes and discriminate genotoxic carcinogens from non-genotoxic carcinogens and non-carcinogens. However, early gene changes induced by genotoxic compounds in human liver remain largely unknown. Primary human hepatocytes and differentiated HepaRG cells were exposed to aflatoxin B1 (AFB1) that induces DNA damage following enzyme-mediated bioactivation. Gene expression profile changes induced by a 24 h exposure of these hepatocyte models to 0.05 and 0.25 μM AFB1 were analyzed by using oligonucleotide pangenomic microarrays. The main altered signaling pathway was the p53 pathway and related functions such as cell cycle, apoptosis and DNA repair. Direct involvement of the p53 protein in response to AFB1 was verified by using siRNA directed against p53. Among the 83 well-annotated genes commonly modulated in two pools of three human hepatocyte populations and HepaRG cells, several genes were identified as altered by AFB1 for the first time. In addition, a subset of 10 AFB1-altered genes, selected upon basis of their function or tumor suppressor role, was tested in four human hepatocyte populations and in response to other chemicals. Although they exhibited large variable inter-donor fold-changes, several of these genes, particularly FHIT, BCAS3 and SMYD3, were found to be altered by various direct and other indirect genotoxic compounds and unaffected by non-genotoxic compounds. Overall, this comprehensive analysis of early gene expression changes induced by AFB1 in human hepatocytes identified a gene subset that included several genes representing potential biomarkers of genotoxic compounds. -- Highlights: ► Gene expression profile changes induced by aflatoxin B1 in human hepatocytes. ► AFB1 modulates various genes including tumor suppressor genes and proto-oncogenes. ► Important inter-individual variations in the response to AFB1. ► Some genes also altered by other

  5. A novel method for determination of aflatoxin B1 mediated by FCLA + BSA

    NASA Astrophysics Data System (ADS)

    Chen, WenLi; Xing, Da

    2005-02-01

    As a chemiluminescence (CL) probe, 3,7-dihydro-6-{4-{2-(N"-(5-fluoresceinyl) thioureido)ethoxy}phenyl}-2-met -hylimi-dazo{1,2-a}pyrazin-3-one dosium salt (FCLA) can sensitively and specifically react with singlet oxygen (1O2 ) and superoxide(O2""). BSA (Bovine Serum Albumin) can enlarge the CL intensity of FCLA to 860%. This report presents a novel method for determination of Aflatoxin B1 (AfB1) mediated by FCLA+BSA. The concentration of AFB1 showed an obvious positive correlation with the CL intensity mediated by FCLA+BSA. This method could measure accurately ng/ml of AfB1 concentration. At the same time, the fluorescence spectrum of FCLA+BSA and FCLA+BSA+AfB1 were measured respectively, which showed that the fluorescence intensity of FCLA+BSA+AfB1 was higher than FCLA+BSA. Comparing the peak value of FCLA, FCLA+BSA and FCLA+BSA+AfB1 had a 6nm Einstein shift (red shift). The study suggested that CL method mediated by FCLA+BSA might be applicable to the determination of AfB1 concentration.

  6. Further evidence supporting the concurrent influence of aflatoxin and manganese

    SciTech Connect

    Katzen, J.S.; Llewellyn, G.C.

    1987-04-01

    Trace elements, including manganese may afford protection from deleterious effects of aflatoxin. Young male Fischer rats received ip injections of aflatoxin B1 (AFB1) in dimethyl sulfoxide (DMSO), 1 mg/kg, 2 mg/kg or 4 mg/kg. Control groups received DMSO ip or no injection. All animals were intubated with 3 microCi of (/sup 54/Mn)-MnCl/sub 2/ 12 hr post-injection. Sacrifice occurred 72 hr after gavage of the radiolabel. All tested levels of AFB1 affected the loss of total body radioactivity. This response was observed within 12 hr when toxin-treated groups excreted almost 4 times more counts than controls. From 12-36 hr following radiolabel administration, AFB1 appeared to enhance excretion; by 72 hr, toxin-treated animals (especially those receiving higher doses) appeared to conserve the metal. Aflatoxicosis manifested itself through reduced body weight gain. The data provide support evidence that Mn and AFB1 biointeract.

  7. Determination of aflatoxin M1 in breast milk as a biomarker of maternal and infant exposure in Colombia.

    PubMed

    Diaz, Gonzalo J; Sánchez, Marlib Paloma

    2015-01-01

    Chronic exposure to aflatoxins, and especially to aflatoxin B1 (AFB1), causes hepatocellular carcinoma with prevalence 16-32 times higher in developing compared with developed countries. Aflatoxin M1 (AFM1) is a monohydroxylated metabolite from AFB1 that is secreted in milk and which can be used as a biomarker of AFB1 exposure. This study aimed to determine AFM1 levels in human breast milk using immunoaffinity column clean-up with HPLC and fluorescence detection. Breast milk samples were obtained from 50 nursing mothers. Volunteers filled in a questionnaire giving their consent to analyse their samples as well as details of their socioeconomic, demographic and clinical data. The possible dietary sources of aflatoxins were assessed using a food frequency questionnaire. A total of 90% of the samples tested positive for AFM1, with a mean of 5.2 ng l(-1) and a range of 0.9-18.5 ng l(-1). The study demonstrated a high frequency of exposure of mothers and neonates to AFB1 and AFM1 in Colombia, and it points out the need to regulate and monitor continuously the presence of aflatoxins in human foods. Further research is needed in order to determine the presence of other mycotoxins in foods and in human samples as well as to devise protection strategies in a country where mycotoxins in human foods are commonly found.

  8. Comparison of S9 mix and hepatocytes as external metabolizing systems in mammalian cell cultures: cytogenetic effects of 7,12-dimethylbenzanthracene and aflatoxin B1

    SciTech Connect

    Madle, E.; Tiedemann, G.; Madle, S.; Oett, A.; Kaufmann, G.

    1986-01-01

    Two external metabolizing systems, S9 mix from Aroclor-induced rat livers and freshly isolated hepatocytes, were used for activation in cultures of human lymphocytes and V79 cells. 7, 12-dimethylbenzanthracene (DMBA) and aflatoxin B1 (AFB1) were employed as indirectly acting reference mutagens. Mutagenic effects were measured by induction of sister chromatid exchange (SCE). With DMBA, SCE-inducing effects were found to be quite similar after activation by S9 mix and activation by hepatocytes. In contrast with AFB1, S9 activation led to a stronger SCE induction than hepatocyte activation in both target cells. The induction of chromosomal aberrations by AFB1 after activation by the two metabolizing systems was also analyzed in V79 cells. This experiment again revealed that AFB1 was more efficiently activated by S9 mix than by hepatocytes. The experiments have shown that the suitability of hepatocytes as an activation system is not restricted to microbial or eukaryotic point mutation assays, but that hepatocyte metabolism can also be successfully included in cytogenetic tests with short- and long-term cultures of mammalian target cells.

  9. Aflatoxin B₁ and aflatoxins in ground red chilli pepper after drying.

    PubMed

    Özkan, Ali; Bindak, Recep; Erkmen, Osman

    2015-01-01

    In this study, 180 red chilli pepper (RCP) berry samples were obtained from two different croplands of Gaziantep and Kahramanmaraş (Turkey) in August, September and October. RCP berry samples were dried under sunlight and grinded. Ground red chilli pepper (GRCP) samples were analysed for aflatoxins (AFs, sum of B1, B2, G1 and G2) and AFB1 contamination. According to the results, in 49 of 180 samples, AFB1 and in 37 samples, AFs were higher than legal limits. The lowest amounts of AFs and AFB1 were obtained in August and the highest amounts in October. χ(2) analysis showed that there were no significant differences (p > 0.05) between cities among 3 months according to number of samples with AFs and AFB1 above legal limits. According to the Duncan multiple-range test, there was no significant difference between all months. Strict measures are necessary to produce high-quality GRCP. RCP berry must be treated to reduce moulds before production of GRCP.

  10. Functional and phylogenetic analysis of the Aspergillus ochraceoroseus aflQ (ordA) gene ortholog

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Within the Aspergillus parasiticus and A. flavus aflatoxin (AF) biosynthetic gene cluster the aflQ (ordA) and aflP (omtA) genes encode an oxidoreductase and methyltransferase, respectively. These genes are required for the final steps in the conversion of sterigmatocystin (ST) to aflatoxin B1 (AFB1...

  11. Co-exposure to fumonisins and aflatoxins in maize-based foods in central america: guatemala as a case study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxin B1 (AFB1) is a human liver carcinogen having a genotoxic mechanism of action. The ceramide synthase inhibitor fumonisin B1 (FB1) is a liver cancer promoter in rats and trout. Both mycotoxins are found in maize so that the possibility of co-exposure is a health concern, especially in Centra...

  12. Detection of mycotoxins using imaging surface plasmon resonance (iSPR)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Significant progress has been made in the development of biosensors that can be used to detect mycotoxins. One technology that has been extensively tested is surface plasmon resonance (SPR). In 2003 a multi-toxin method was reported that detected aflatoxin B1 (AFB1), zearalenone (ZEA), fumonisin B1 ...

  13. Transport via xylem and accumulation of aflatoxin in seeds of groundnut plant.

    PubMed

    Snigdha, M; Hariprasad, P; Venkateswaran, G

    2015-01-01

    Aflatoxin contamination in groundnut seeds in the absence of any aflatoxigenic fungi leads to a hypothesis that aflatoxins are present naturally in soil and is transferred to seeds through uptake by roots. A survey was conducted on the natural occurrence of aflatoxins in agricultural soils, among nine main groundnut-growing regions of Karnataka state, India. All 71 soil samples collected in this survey were contaminated with aflatoxins esp. AFB1. An in vitro xylem sap experiment proved the ability of groundnut plant roots to absorb AFB1, and transport to aerial plant parts via the xylem. Hydroponics experiment also proved the uptake of AFB1 by the roots and their translocation to shoot. Uptake was affected by the initial concentration of toxin and pH of the medium. Among the 14 varieties screened, GPBD4 and MLT.K.107 (III) recorded highest and least AFB1 uptake, respectively. The above results were validated using a greenhouse experiment. Here, the aflatoxin absorbed by root gradually transferred to shoot that was later found in seeds towards the end of experiment. Thus, the groundnut seeds can also get contaminated with aflatoxin by direct uptake of aflatoxin through conducting tissue in addition to fungal infection. The present study revealed the novel mode of aflatoxin contamination in groundnut seeds without fungal infection.

  14. Inhibition of the Aspergillus flavus Growth and Aflatoxin B1 Contamination on Pistachio Nut by Fengycin and Surfactin-Producing Bacillus subtilis UTBSP1

    PubMed Central

    Farzaneh, Mohsen; Shi, Zhi-Qi; Ahmadzadeh, Masoud; Hu, Liang-Bin; Ghassempour, Alireza

    2016-01-01

    In this study, the treatment of pistachio nuts by Bacillus subtilis UTBSP1, a promising isolate to degrade aflatoxin B1 (AFB1), caused to reduce the growth of Aspergillus flavus R5 and AFB1 content on pistachio nuts. Fluorescence probes revealed that the cell free supernatant fluid from UTBSP1 affects spore viability considerably. Using high-performance liquid chromatographic (HPLC) method, 10 fractions were separated and collected from methanol extract of cell free supernatant fluid. Two fractions showed inhibition zones against A. flavus. Mass spectrometric analysis of the both antifungal fractions revealed a high similarity between these anti-A. flavus compounds and cyclic-lipopeptides of surfactin, and fengycin families. Coproduction of surfactin and fengycin acted in a synergistic manner and consequently caused a strong antifungal activity against A. flavus R5. There was a positive significant correlation between the reduction of A. flavus growth and the reduction of AFB1 contamination on pistachio nut by UTBSP1. The results indicated that fengycin and surfactin-producing B. subtilis UTBSP1 can potentially reduce A. flavus growth and AFB1 content in pistachio nut. PMID:27298596

  15. The Efficacy of Bamboo Charcoal in Comparison with Smectite to Reduce the Detrimental Effect of Aflatoxin B1 on In Vitro Rumen Fermentation of a Hay-Rich Feed Mixture

    PubMed Central

    Jiang, Ya-Hui; Wang, Ping; Yang, Hong-Jian; Chen, Ying

    2014-01-01

    Two commercial materials, a bamboo charcoal (BC) and a smectite clay (SC), were assessed in vitro with aflatoxin B1 (AFB1) in an equilibrium adsorption test. The adsorption capacity and proportion adsorbed (0.381 μg/mg, 0.955) for BC were greater than for SC (0.372 μg/mg, 0.931). The effects of in vitro ruminal fermentation of hay-rich feed incubated with 1.0 μg/mL AFB1 for 0–10 g/L doses of BC and SC were measured at 39 °C for 72 h. The BC and SC binders increased AFB1 loss at dosages ≥1.0 g/L (p < 0.0001). Average AFB1 loss (p < 0.0001) was greater for SC (0.904) than BC (0.881). Both SC and SC addition increased in vitro dry matter loss, and the average dry matter losses were similar. Asymptotic gas volume and volatile fatty acid production were greater for BC than for SC (p < 0.0001). Thus, BC may be as effective as SC in removing aflatoxin B1’s detrimental effects on rumen degradability and fermentation under the occurrence of microbial aflatoxin degradation. PMID:25014194

  16. Feasibility of detecting Aflatoxin B1 in single maize kernels using hyperspectral imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The feasibility of detecting Aflatoxin B1 (AFB1) in single maize kernel inoculated with Aspergillus flavus conidia in the field, as well as its spatial distribution in the kernels, was assessed using near-infrared hyperspectral imaging (HSI) technique. Firstly, an image mask was applied to a pixel-b...

  17. Shopping Survey of the Military Consumer at Whiteman Air Force Base

    DTIC Science & Technology

    1991-02-21

    during the week (12) 1 No place for brunch on Sunday (13) 1 Poor Quality (15) 1 Poor Service (16) 1 Base facilities are handy (17) 1 Enjoys shopping...1 Umited amount of facilities (7) 1 Need more parking (8) 1 No place for brunch on Sunday B. Auto Hobby Shop (Whiteman AFB) (1) 1 Need to improve

  18. Potential Antioxidant Role of Tridham in Managing Oxidative Stress against Aflatoxin-B1-Induced Experimental Hepatocellular Carcinoma

    PubMed Central

    Ravinayagam, Vijaya; Jaganathan, Ravindran; Panchanadham, Sachdanandam; Palanivelu, Shanthi

    2012-01-01

    Hepatocellular carcinoma (HCC) is one of the most fatal cancers due to delayed diagnosis and lack of effective treatment options. Significant exposure to Aflatoxin B1 (AFB1), a potent hepatotoxic and hepatocarcinogenic mycotoxin, plays a major role in liver carcinogenesis through oxidative tissue damage and p53 mutation. The present study emphasizes the anticarcinogenic effect of Tridham (TD), a polyherbal traditional medicine, on AFB1-induced HCC in male Wistar rats. AFB1-administered HCC-bearing rats (Group II) showed increased levels of lipid peroxides (LPOs), thiobarbituric acid substances (TBARs), and protein carbonyls (PCOs) and decreased levels of enzymic and nonenzymic antioxidants when compared to control animals (Group I). Administration of TD orally (300 mg/kg body weight/day) for 45 days to HCC-bearing animals (Group III) significantly reduced the tissue damage accompanied by restoration of the levels of antioxidants. Histological observation confirmed the induction of tumour in Group II animals and complete regression of tumour in Group III animals. This study highlights the potent antioxidant properties of TD which contribute to its therapeutic effect in AFB1-induced HCC in rats. PMID:22518320

  19. Probiotic preparation reduces the faecal water genotoxicity in chickens fed with aflatoxin B1 contaminated fodder.

    PubMed

    Slizewska, Katarzyna; Nowak, Adriana; Libudzisz, Zdzislawa; Blasiak, Janusz

    2010-12-01

    The aim of the study was to evaluate the influence of a probiotic preparation on the genotoxicity of faecal water of broiler chickens fed with a fodder contaminated with aflatoxin B(1) (AFB(1)) at 1 or 5mg per kg. Human blood lymphocytes were exposed to chicken's faecal water samples and DNA damage was measured using the comet assay. Genotoxicity of faecal water did not depend on the AFB(1) concentration in the fodder. The mean DNA damage, measured as the percentage of DNA in the tail of the comets, for chickens fed with fodder with AFB(1) at 1 mg/kg was 16.80±0.66, at 5 mg/kg - 16.73±1.51 and in the controls - 12.79±0.66. The supplementation of fodder with the probiotic preparation decreased the extent of DNA damage to 10.02±0.39 for 1 mg/kg AFB(1) and to 11.89±0.72 for 5 mg/kg.

  20. Transfer of aflatoxin B1 and fumonisin B1 from naturally contaminated raw materials to beer during an industrial brewing process.

    PubMed

    Pietri, A; Bertuzzi, T; Agosti, B; Donadini, G

    2010-10-01

    The aim of this research was to determine the fate of aflatoxins (AFs) and fumonisins (FBs) naturally occurring in raw materials (maize grit and malted barley) during four industrial brewing processes. The aflatoxin B(1) (AFB(1)) level in raw materials varied from 0.31 to 14.85 microg kg(-1), while the fumonisin B(1) (FB(1)) level (only in maize grit) varied from 1146 to 3194 microg kg(-1). The concentration in finished beer ranged from 0.0015 to 0.022 microg l(-1) for AFB(1) and from 37 to 89 microg l(-1) for FB(1); the other aflatoxins and fumonisin B(2) were not found in beer samples. The average percentage of toxins recovered in finished beer, referring to the amounts contained in raw materials, were 1.5% +/- 0.8% for AFB(1) and 50.7% +/- 4.7% for FB(1). These results were mainly due to the different solubility of the two mycotoxins during the mashing process. If raw materials comply with the limits fixed by European Commission Regulations, the contribution of a moderate daily consumption of beer to AFB(1) and FB(1) intake does not contribute significantly to the exposure of the consumer.

  1. Non-linear relationships between aflatoxin B1 levels and the biological response of monkey kidney vero cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aflatoxin (AF)-producing fungi contaminate food and feed during preharvest, storage and processing periods. Once consumed, AF accumulates in tissues, causing illnesses in animals and humans. At least 20 different types of AFs have been identified, and of these, aflatoxin B1 (AFB1) is the most ubiqui...

  2. Characterization of toxigenic and atoxigenic Aspergillus flavus isolates from pistachio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty eight Aspergillus flavus isolates collected from a pistachio orchard in California were analyzed for production of aflatoxin (AF), cyclopiazonic acid (CPA), vegetative compatibility groups (VCGs) and mating types. All toxigenic isolates produced both AFB1 and CPA. Twenty-one percent of the i...

  3. The effect of NovaSil dietary supplementation on the growth and health performance of Nile tilapia (Oreochromis niloticus) fed aflatoxin-B1 contaminated feed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate the ability of NovaSil (NS) clay to sorb and mitigate the toxic effects of aflatoxin B1 (AFB1) in Nile tilapia (Oreochromis niloticus). Growth performance, specific innate immunological function, intestinal microbial community, and histology were evaluate...

  4. Feasibility of detecting aflatoxin B1 on inoculated maize kernels surface using Vis/NIR hyperspectral imaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The feasibility of using a visible/near-infrared hyperspectral imaging system with a wavelength range between 400 and 1000 nm to detect and differentiate different levels of aflatoxin B1 (AFB1) artificially titrated on maize kernel surface was examined. To reduce the color effects of maize kernels, ...

  5. A Structure Identification and Toxicity Assessment of the Degradation Products of Aflatoxin B1 in Peanut Oil under UV Irradiation

    PubMed Central

    Mao, Jin; He, Bing; Zhang, Liangxiao; Li, Peiwu; Zhang, Qi; Ding, Xiaoxia; Zhang, Wen

    2016-01-01

    Aflatoxins, a group of extremely hazardous compounds because of their genotoxicity and carcinogenicity to human and animals, are commonly found in many tropical and subtropical regions. Ultraviolet (UV) irradiation is proven to be an effective method to reduce or detoxify aflatoxins. However, the degradation products of aflatoxins under UV irradiation and their safety or toxicity have not been clear in practical production such as edible oil industry. In this study, the degradation products of aflatoxin B1 (AFB1) in peanut oil were analyzed by Ultra Performance Liquid Chromatograph-Thermo Quadrupole Exactive Focus mass spectrometry/mass spectrometry (UPLC-TQEF-MS/MS). The high-resolution mass spectra reflected that two main products were formed after the modification of a double bond in the terminal furan ring and the fracture of the lactone ring, while the small molecules especially nitrogen-containing compound may have participated in the photochemical reaction. According to the above results, the possible photodegradation pathway of AFB1 in peanut oil is proposed. Moreover, the human embryo hepatocytes viability assay indicated that the cell toxicity of degradation products after UV irradiation was much lower than that of AFB1, which could be attributed to the breakage of toxicological sites. These findings can provide new information for metabolic pathways and the hazard assessment of AFB1 using UV detoxification. PMID:27845743

  6. Inhibitory Effects of Thai Essential Oils on Potentially Aflatoxigenic Aspergillus parasiticus and Aspergillus flavus.

    PubMed

    Jantapan, Kittika; Poapolathep, Amnart; Imsilp, Kanjana; Poapolathep, Saranya; Tanhan, Phanwimol; Kumagai, Susumu; Jermnak, Usuma

    2017-01-01

     The antiaflatoxigenic and antifungal activities of essential oils (EOs) of finger root (Boesenbergia rotunda (L.) Mansf.), pine (Pinus pinaster), rosewood (Aniba rosaedora), Siam benzoin (Styrax tonkinensis), Thai moringa (Moringa oleifera), and ylang ylang (Cananga odorata) were tested for Aspergillus parasiticus and Aspergillus flavus in potato dextrose broth. Aflatoxin B1 (AFB1) was extracted from culture using a QuEChERS-based extraction procedure and analyzed with high performance liquid chromatography (HPLC) coupled to a fluorescence detector. EO of pine showed the greatest inhibition of growth and AFB1 production of A. parasiticus, followed by EOs of rosewood, finger root, Siam benzoin, and ylang ylang. EO of finger root gave the best inhibitory effects on A. flavus, followed by EOs of rosewood, pine, ylang ylang, and Siam benzoin. EO of Thai moringa did not show any significant inhibition of aflatoxigenic fungi. The antiaflatoxigenic activities of EOs correlated with their antifungal activities in the dosedependent manner. Comparison of the application of the five selected EOs in peanut pods by direct and vapor exposure indicated that the AFB1 production inhibitory effects of the five EOs by direct exposure were faster and more effective than by vapor exposure. EO of finger root showed the best inhibition of AFB1 production of A. flavus in peanut pods by direct exposure, followed by EOs of pine, rosewood, ylang ylang, and Siam benzoin.

  7. Survey of Deoxynivalenol and Aflatoxin B1 in Instant Noodles and Bread Consumed in Thailand by Using Liquid Chromatography-Tandem Mass Spectrometry.

    PubMed

    Pralatnet, Sasithorn; Poapolathep, Saranya; Giorgi, Mario; Imsilp, Kanjana; Kumagai, Susumu; Poapolathep, Amnart

    2016-07-01

    One hundred wheat product samples (50 instant noodle samples and 50 bread samples) were collected from supermarkets in Bangkok, Thailand. Deoxynivalenol (DON) and aflatoxin B1 (AFB1) contamination in these products was analyzed using a validated liquid chromatography-tandem mass spectrometry method. The limit of quantification values of DON and AFB1 in the instant noodles and bread were 2 and 1 ng g(-1), respectively. The survey found that DON was quantifiable in 40% of collected samples, in 2% of noodles (0.089 μg g(-1)), and in 78% of breads (0.004 to 0.331 μg g(-1)). AFB1 was below the limit of quantification of the method in all of the tested samples. The results suggest that the risk of DON exposure via noodles and breads is very low in urban areas of Thailand. No risk can be attributable to AFB1 exposure in the same food matrices, but further studies with a larger sample size are needed to confirm these data.

  8. The master transcription factor mtfA governs aflatoxin production, morphological development, and pathogenicity in the fungus Aspergillus flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus flavus produces a variety of toxic secondary metabolites, among them the aflatoxins (AFs) are the most well-known. These compounds are highly mutagenic and carcinogenic, particularly AFB1. A. flavus is capable of colonizing economically important crops contaminating them with AFs. Molecu...

  9. The mitochondrial and death receptor pathways involved in the thymocytes apoptosis induced by aflatoxin B1

    PubMed Central

    Chi, Xiaofeng; Li, Xiaochong; Jiang, Min; Fang, Jing; Cui, Hengmin; Lai, Weimin; Zhou, Yi; Zhou, Shan

    2016-01-01

    Aflatoxin B1 (AFB1) is a potent immunosuppressive agent in endotherms, which can be related to the up-regulated apoptosis of immune organs. In this study, we investigated the roles of the mitochondrial, death receptor, and endoplasmic reticulum pathways in Aflatoxin B1 induced thymocytes apoptosis. Chickens were fed an aflatoxin B1 containing diet (0.6 mg/kg AFB1) for 3 weeks. Our results showed that (1) AFB1 diet induced the decrease of T-cell subsets, morphological changes, and excessive apoptosis of thymus. (2) The excessive apoptosis involved the mitochondrial pathway (up-regulation of Bax, Bak, cytC and down-regulation of Bcl-2 and Bcl-xL) and death receptor pathway (up-regulation of FasL, Fas and FADD). (3) Oxidative stress, an apoptosis inducer, was confirmed in the thymus. In conclusion, this is the first study to demonstrate that mitochondrial and death receptor pathways involved in AFB1 induced thymocytes apoptosis in broilers. PMID:26933817

  10. The furofuran-ring selectivity, hydrogen peroxide-production and low Km value are the three elements for highly effective detoxification of aflatoxin oxidase.

    PubMed

    Wu, Yuan-Zhen; Lu, Fu-Pu; Jiang, Hai-Lan; Tan, Cui-Ping; Yao, Dong-Sheng; Xie, Chun-Fang; Liu, Da-Ling

    2015-02-01

    AFO (aflatoxin oxidase), an enzyme from Armillariella tabescens previously named aflatoxin detoxifizyme, exhibits oxidative detoxification activity toward aflatoxin B1 and sterigmatocystin. Bioinformatics reveals that AFO is a newly discovered oxidase because AFO does not share any significant similarities with any known oxidase. It is critically important to understand how AFO acts on aflatoxin B1. In this study, in addition to aflatoxin B1 (AFB1) and sterigmatocystin (ST), five other chemicals that have furan or pyran structures were investigated. The results indicated that in addition to AFB1 and ST, AFO is also able to act on versicolorin A, 3,4-dihydro-2H-pyran and furan. These results suggested that 8,9-unsaturated carboncarbon bond of aflatoxin B1 is the potential reactive site for AFO. Further findings indicated that the action of AFO is oxygen-dependent and hydrogen peroxide-producing. The simultaneously produced-hydrogen peroxide possibly plays the essential role in detoxification of AFO. In addition, the extremely low Km value of 0.33 µmol/l for AFO-AFB1 and 0.11 µmol/l for AFO-ST signifies that AFO is highly selective for AFB1 as well as ST.

  11. A Survey of Aflatoxin-Producing Aspergillus sp. from Peanut Field Soils in Four Agroecological Zones of China

    PubMed Central

    Zhang, Chushu; Selvaraj, Jonathan Nimal; Yang, Qingli; Liu, Yang

    2017-01-01

    Peanut pods are easily infected by aflatoxin-producing Aspergillus sp.ecies from field soil. To assess the aflatoxin-producing Aspergillus sp. in different peanut field soils, 344 aflatoxin-producing Aspergillus strains were isolated from 600 soil samples of four agroecological zones in China (the Southeast coastal zone (SEC), the Yangtze River zone (YZR), the Yellow River zone (YR) and the Northeast zone (NE)). Nearly 94.2% (324/344) of strains were A. flavus and 5.8% (20/344) of strains were A. parasiticus. YZR had the highest population density of Aspergillus sp. and positive rate of aflatoxin production in isolated strains (1039.3 cfu·g−1, 80.7%), the second was SEC (191.5 cfu·g−1, 48.7%), the third was YR (26.5 cfu·g−1, 22.7%), and the last was NE (2.4 cfu·g−1, 6.6%). The highest risk of AFB1 contamination on peanut was in YZR which had the largest number of AFB1 producing isolates in 1g soil, followed by SEC and YR, and the lowest was NE. The potential risk of AFB1 contamination in peanuts can increase with increasing population density and a positive rate of aflatoxin-producing Aspergillus sp. in field soils, suggesting that reducing aflatoxigenic Aspergillus sp. in field soils could prevent AFB1 contamination in peanuts. PMID:28117685

  12. Low levels of aflatoxin B1, ricin and milk enhance recombinant protein production in mammalian cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Changing the optimal tissue culture medium by adding low levels of environmental stress such as 1 µM of the fungal toxin aflatoxin B1 (AFB1), 1 ng of the castor bean protein toxin ricin in transduced mammalian cells or 1% reconstituted milk enhances transcription and increases production of the foll...

  13. On the occurrence of aflatoxin M1 in milk and dairy products.

    PubMed

    Prandini, A; Tansini, G; Sigolo, S; Filippi, L; Laporta, M; Piva, G

    2009-05-01

    Aflatoxins are toxic fungal metabolites found in foods and feeds. When ruminants eat AFB(1)-feedstuffs, they metabolise the toxin and excrete AFM(1) in milk. To control AFM(1) in foods it is necessary to reduce AFB(1) contamination of feeds for dairy cattle by preventing fungal growth and AFB(1) formation in agricultural commodities intended for animal use. Corn and corn-based products are one of the most contaminated feedstuffs; therefore risk factor analysis of AFB(1) contamination in corn is necessary to evaluate risk of AFM(1) contamination in milk and milk products. During the corn silage production, the aflatoxins production is mostly influenced by: harvest time; fertilization; irrigation; pest control; silage moisture; and storage practices. Due to the lower moisture at harvest and to the conservation methods, the corn grain is mostly exposed to the contamination by Aspergillus species. Therefore, it is necessary to reduce the probability of this contaminant through choice of: hybrids; seeding time and density; suitable ploughing and fertirrigation; and chemical or biological control. Grains harvested with the lowest possible moisture and conservation moisture close to or less than 14% are necessary to reduce contamination risks, as is maintaining mass to homogeneous moisture. Kernel mechanical damage, grain cleaning practices and conservation temperature are also factors which need to be carefully controlled.

  14. Chronic aflatoxin exposure in children living in Bhaktapur, Nepal: Extension of the MAL-ED study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumonisin B1 (FB1) and aflatoxin B1 (AFB1) are toxic chemicals produced by molds. The molds that produce these two toxic chemicals are commonly found in corn and their co-occurence in corn has been demonstrated in many surveys. This study was conducted because it is suspected that exposure to eith...

  15. Public health risk associated with the co-occurrence of mycotoxins in spices consumed in Sri Lanka.

    PubMed

    Yogendrarajah, Pratheeba; Jacxsens, Liesbeth; Lachat, Carl; Walpita, Chaminda Niroshan; Kolsteren, Patrick; De Saeger, Sarah; De Meulenaer, Bruno

    2014-12-01

    A quantitative risk assessment of mycotoxins due to the consumption of chilli (Capsicum annum L.) and black pepper (Piper nigrum L.) was performed in Sri Lanka. A food frequency questionnaire was administered in order to collect the data on consumption of spices by households in the Northern and Southern region (n = 249). The mean chilli consumption in the North was significantly higher (p < 0.001) compared to the South. Mean exposure to aflatoxin B1 (AFB1) in the North (3.49 ng/kg BW/day) and South (2.13 ng/kg BW/day) have exceeded the tolerable daily intake due to chilli consumption at the lower bound scenario, while exposure to OTA was small. Dietary exposure to other mycotoxins, fumonisin B1, fumonisin B2, sterigmatocystin and citrinin due to spices were estimated. Margin of exposure estimations at the mean exposure to AFB1 were remarkably lower due to chilli (45-78) than for pepper (2315–10,857). Moreover, the hepato cellular carcinoma (HCC) risk associated with the mean AFB1 exposure through chilli at the lower bound was 0.046 and 0.028 HCC cases/year/100,000 based on the North and South consumption, respectively. AFB1 exposure via chilli should be considered as a great public health concern in Sri Lanka due to both high mycotoxin concentration and high consumption.

  16. Potential for amelioration of aflatoxin B1-induced immunotoxic effects in progeny of White Leghorn breeder hens co-exposed to vitamin E.

    PubMed

    Khan, Wajid Arshad; Khan, Muhammad Zargham; Khan, Ahrar; Ul Hassan, Zahoor; Saleemi, Muhammad Kashif

    2014-01-01

    This study was designed to evaluate the protective activity of Vitamin E (Vit E) on the immunotoxic effects induced by aflatoxin B1 (AFB1) in the progeny of breeder hens. For this purpose, 192 White Leghorn (WL) layer breeder hens were divided into 12 groups (A-L) and then fed test diets for either 1, 2 or 3 weeks. Group A was kept on basal feed (2900 Kcal/kg metabolizable energy) and served as control, while group B was offered a feed supplemented with Vit E at 100 mg/Kg. Groups C-G were offered feed containing 0.1, 0.5, 2.5, 5.0, and 10.0 mg/Kg AFB1, respectively, whereas groups H-L were offered the same dietary levels of AFB1 along with 100 mg/Kg Vit E supplementation. Hatching eggs were shifted to an incubator on a weekly basis to get progeny chicks. Hatched chicks in each group were maintained on basal ration and then subjected to different immunological assays. Lymphoproliferative responses (against PHA-P), antibody titers (against SRBC), oxidative damage to RBC, as well as phagocytic and nitrite production potential of the peritoneal macrophages from the chicks, were all adversely impacted by hen exposure to the higher doses of AFB1 or by increased intake (time) by the hens at a given dose of the toxin. No consistent ameliorative effects from Vit E were noted in these studies, i.e. effects seen against lower AFB1 doses were no longer apparent with the highest doses of AFB1. As such, for now it can be concluded that, with this particular single dose level of Vit E, AFB1-associated immunotoxic effects in progeny chicks can potentially be mitigated by dietary intake of Vit E by their hen dams. However, this is clearly an outcome that is driven by the level of the mycotoxin present in the feed. Future studies need to examine what impact higher Vit E doses than those employed herein might have in these ameliorative outcomes.

  17. Low-cost and highly sensitive immunosensing platform for aflatoxins using one-step competitive displacement reaction mode and portable glucometer-based detection.

    PubMed

    Tang, Dianping; Lin, Youxiu; Zhou, Qian; Lin, Yuping; Li, Peiwu; Niessner, Reinhard; Knopp, Dietmar

    2014-11-18

    Aflatoxins are highly toxic secondary metabolites produced by a number of different fungi and present in a wide range of food and feed commodities. Herein, we designed a simple and low-cost immunosensing platform for highly sensitive detection of mycotoxins (aflatoxin B1, AFB1, used as a model) on polyethylenimine (PEI)-coated mesoporous silica nanocontainers (PEI-MSN). The assay was carried out by using a portable personal glucometer (PGM) as the readout based on a competitive displacement reaction mode between target AFB1 and its pseudo-hapten (PEI-MSN) for monoclonal anti-AFB1 antibody (mAb). To construct such an assay protocol, two nanostructures including mAb-labeled gold nanoparticle (mAb-AuNP) and PEI-MSN were initially synthesized, and then numerous glucose molecules were gated into the pores based on the interaction between negatively charged mAb-AuNP and positively charged PEI-MSN. In the presence of target AFB1, a competitive-type displacement reaction was implemented between mAb-AuNP and PEI-MSN by target AFB1 through the specific antigen-antibody reaction. Accompanying the reaction, target AFB1 could displace the mAb-AuNP from the surface of PEI-MSN, resulting in the release of the loading glucose from the pores due to the gate opened. The released glucose molecules could be quantitatively determined by using a portable PGM. Under optimal conditions, the PGM signal increased with the increment of AFB1 concentration in the range from 0.01 to 15 μg/kg (ppb) with a detection limit (LOD) of 5 ng/kg (5 ppt) at the 3sblank criterion. The selectivity and precision were acceptable. Importantly, the methodology was further validated for assaying naturally contaminated or spiked blank peanut samples, and consistent results between the PGM-based immunoassay and the referenced enzyme-linked immunosorbent assay (ELISA) were obtained. Therefore, the developed immunoassay provides a promising approach for rapid screening of organic pollutants because it is simple

  18. Aflatoxin B1 and M1 Degradation by Lac2 from Pleurotus pulmonarius and Redox Mediators

    PubMed Central

    Loi, Martina; Fanelli, Francesca; Zucca, Paolo; Liuzzi, Vania C.; Quintieri, Laura; Cimmarusti, Maria T.; Monaci, Linda; Haidukowski, Miriam; Logrieco, Antonio F.; Sanjust, Enrico; Mulè, Giuseppina

    2016-01-01

    Laccases (LCs) are multicopper oxidases that find application as versatile biocatalysts for the green bioremediation of environmental pollutants and xenobiotics. In this study we elucidate the degrading activity of Lac2 pure enzyme form Pleurotus pulmonarius towards aflatoxin B1 (AFB1) and M1 (AFM1). LC enzyme was purified using three chromatographic steps and identified as Lac2 through zymogram and LC-MS/MS. The degradation assays were performed in vitro at 25 °C for 72 h in buffer solution. AFB1 degradation by Lac2 direct oxidation was 23%. Toxin degradation was also investigated in the presence of three redox mediators, (2,2′-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]) (ABTS) and two naturally-occurring phenols, acetosyringone (AS) and syringaldehyde (SA). The direct effect of the enzyme and the mediated action of Lac2 with redox mediators univocally proved the correlation between Lac2 activity and aflatoxins degradation. The degradation of AFB1 was enhanced by the addition of all mediators at 10 mM, with AS being the most effective (90% of degradation). AFM1 was completely degraded by Lac2 with all mediators at 10 mM. The novelty of this study relies on the identification of a pure enzyme as capable of degrading AFB1 and, for the first time, AFM1, and on the evidence that the mechanism of an effective degradation occurs via the mediation of natural phenolic compounds. These results opened new perspective for Lac2 application in the food and feed supply chains as a biotransforming agent of AFB1 and AFM1. PMID:27563923

  19. Comparative Measurement of In Vitro Paraquat and Aflatoxin B1 Cytotoxicity Using Three Different Cytotoxicity Assays in Pheochromocytoma Cells (PC-12).

    PubMed

    Mohammadi-Bardbori, Afshin; Nejati, Majid; Esmaeili, Jamileh; Ghafari, Homanaz; Ghazi-Khansari, Mahmoud

    2008-01-01

    ABSTRACT Among the herbicides and mycotoxins, paraquat (PQ) and aflatoxin B1 (AFB1) are highly cytotoxic. In this study the toxicity of PQ and AFB1 in the cultured cell were determined using MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide], JG-B (Janus green B), and NR (neutral red) assay by multiwell scanning spectophotometry. JG-B was used not only for the vital staining of mitochondria but also for viability assay and was compared to MTT and NR assay. Various concentrations of paraquat (0.1 mM to 100 mM) and AFB1 (0.001 nM to 10 nM) on the PC-12 cells were investigated. The 50% lethal concentration of toxins (LC50) were determined for PQ (7.70 +/- 2.50, 3.67 +/- 1.53, 4.85 +/- 2.44) and AFB1 (0.16 +/- 0.01, 0.13 +/- 0.04, 0.14 +/- 0.02) as determined by these methods (JG-B, NR, and MTT, respectively). A significant correlation was found among the JG-B and MTT using PQ (r(2) = 0.99, p < 0.05) and significant correlation was also found among the three methods (r(2) = 0.95, 0.93, and 0.92, p < 0.05) using AFB1. No significant correlation was found between JG-B and MTT with NR (r(2) = 0.34 and 0.35, p < 0.05, respectively) using PQ. These results suggest that both methods (MTT assay and JG-B assay) are reliable and are comparable for determining the cytotoxicity. It is concluded that the JG-B assay may be preferable to MTT assay methods because of its simplicity, low cost, sensitivity, and objectivity; in addition, this method takes little time to be done.

  20. Sodium bentonite and monensin under chronic aflatoxicosis in broiler chickens.

    PubMed

    Magnoli, A P; Texeira, M; Rosa, C A R; Miazzo, R D; Cavaglieri, L R; Magnoli, C E; Dalcero, A M; Chiacchiera, S M

    2011-02-01

    Clay feed additives have been increasingly incorporated into animal diets to prevent aflatoxicosis. Due to the nonselective nature of the binding interaction, many important components of the diets could also be made unavailable because of these feed additives. The anticoccidial monensin (MON) could also be sequestered by these clays. The use of sodium bentonite (Na-B) from a mine in the province of Mendoza, Argentina, was investigated as a sequestering agent to prevent the effects of 100 µg/kg of dietary aflatoxin B(1) (AFB(1)). In vitro studies demonstrated that the above Na-B was a good candidate to prevent aflatoxicosis. They also showed that MON competes with AFB(1) for the adsorption sites on the clay surface and effectively displaces the toxin when it is in low concentration. Even though the levels of MON in diets, approximately 55 mg/kg, are high enough to not be significantly changed as a consequence of the adsorption, they can further affect the ability of the clays to bind low levels of AFB(1). An in vivo experiment carried out with poultry showed that 100 µg/kg of AFB(1) does not significantly change productive or biochemical parameters. However, liver histopathology not only confirmed the ability of this particular Na-B to prevent aflatoxicosis but also the decrease of this capacity in the presence of 55 mg/kg of MON. This is the first report stressing this fact and further research should be performed to check if this behavior is a characteristic of the assayed Na-B or of this type of clay. On the other hand, the presence of MON should also be taken into account when assaying the potential AFB(1) binding ability of a given bentonite.

  1. Non-linear relationships between aflatoxin B₁ levels and the biological response of monkey kidney vero cells.

    PubMed

    Rasooly, Reuven; Hernlem, Bradley; He, Xiaohua; Friedman, Mendel

    2013-08-14

    Aflatoxin-producing fungi contaminate food and feed during pre-harvest, storage and processing periods. Once consumed, aflatoxins (AFs) accumulate in tissues, causing illnesses in animals and humans. Most human exposure to AF seems to be a result of consumption of contaminated plant and animal products. The policy of blending and dilution of grain containing higher levels of aflatoxins with uncontaminated grains for use in animal feed implicitly assumes that the deleterious effects of low levels of the toxins are linearly correlated to concentration. This assumption may not be justified, since it involves extrapolation of these nontoxic levels in feed, which are not of further concern. To develop a better understanding of the significance of low dose effects, in the present study, we developed quantitative methods for the detection of biologically active aflatoxin B₁ (AFB1) in Vero cells by two independent assays: the green fluorescent protein (GFP) assay, as a measure of protein synthesis by the cells, and the microculture tetrazolium (MTT) assay, as a measure of cell viability. The results demonstrate a non-linear dose-response relationship at the cellular level. AFB1 at low concentrations has an opposite biological effect to higher doses that inhibit protein synthesis. Additional studies showed that heat does not affect the stability of AFB1 in milk and that the Vero cell model can be used to determine the presence of bioactive AFB1 in spiked beef, lamb and turkey meat. The implication of the results for the cumulative effects of low amounts of AFB1 in numerous foods is discussed.

  2. A simple and rapid optical biosensor for detection of aflatoxin B1 based on competitive dispersion of gold nanorods.

    PubMed

    Xu, Xia; Liu, Xiangjiang; Li, Yanbin; Ying, Yibin

    2013-09-15

    This report illustrates a promising one-step and label-free optical biosensor for determination of aflatoxin B1 (AFB1) that is most commonly found in foods and highly dangerous even at very low concentrations. In this research, gold nanorods (GNRs) were employed as a sensing platform, which showed high stability under high ionic strength conditions without addition of any stabilizing agent. GNR-AFB1-BSA (bovine serum albumin) conjugates aggregated after mixing with free antibodies, resulting in significant changes in absorption intensity. At the same time the existence of AFB1 molecules in samples caused dispersion of nanorods, as a result of competitive immune-reaction with antibodies. By taking advantages of the competitive dispersion of GNRs, the developed method could effectively reduce false results caused by undesirable aggregation, which is a big problem for spherical gold nanoparticles. Absorption intensity of UV-vis spectra served as the sensing indicator, with dynamic light scattering (DLS) measurement as another sensing tool. The designed biosensing system could detect AFB1 in a linear range from 0.5 to 20ngmL(-1), with a good correlation coefficient of 0.99. And the limit of detection (LOD) was 0.16ngmL(-1), indicating an excellent sensitivity with absorbance result. The recoveries of the spiked AFB1 in real peanut samples ranged from 94.2% to 117.3%. Therefore the proposed nano-biosensor was demonstrated to be sensitive, selective, and simple, providing a viable alternative for rapid screening of toxins in agriculture products and foods.

  3. Changes in serum cytokine levels, hepatic and intestinal morphology in aflatoxin B1-induced injury: modulatory roles of melatonin and flavonoid-rich fractions from Chromolena odorata.

    PubMed

    Akinrinmade, Fadeyemi Joseph; Akinrinde, Akinleye Stephen; Amid, Adetayo

    2016-05-01

    Aflatoxins are known to produce chronic carcinogenic, mutagenic, and teratogenic effects, as well as acute inflammatory effects, especially in the gastrointestinal tract. The potentials of the flavonoid-rich extract from Chromolena odorata (FCO) and melatonin (a standard anti-oxidant and anti-inflammatory agent) against aflatoxin B1 (AFB1)-induced alterations in pro-inflammatory cytokine levels and morphology of liver and small intestines were evaluated in this study. We utilized Wistar albino rats (200-230 g) randomly divided into five groups made up of group A, control rats; group B, rats given AFB1 (2.5 mg/kg, intraperitoneal) twice on days 5 and 7; rats in groups C, D, and E were treated with melatonin (10 mg/kg, intraperitoneal) or oral doses of FCO1 (50 mg/kg) and FCO2 (100 mg/kg) for 7 days, respectively, along with AFB1 injection on days 5 and 7. Serum levels of interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) were determined using commercial ELISA kits and histopathological evaluation of the liver, duodenum, and ileum were also carried out. We observed significant elevation (p < 0.05) in serum IL-1β correlating with hemorrhages and leucocytic and lymphocytic infiltration in the liver and intestines as evidences of an acute inflammatory response to AFB1 administration. All treatments yielded significant reduction (p < 0.05) in IL-1β levels, although TNF-α levels were not significantly altered in all rats that received AFB1, irrespective of the treatments. Melatonin and FCO2 produced considerable protection of hepatic tissues, although melatonin was not quite effective in protecting the intestinal lesions. Our findings suggest a modulation of cytokine expression that may, in part, be responsible for the abilities of C. odorata or melatonin in amelioration of hepatic and intestinal lesions associated with aflatoxin B1 injury.

  4. Carry-Over of Aflatoxin B1 to Aflatoxin M1 in High Yielding Israeli Cows in Mid- and Late-Lactation

    PubMed Central

    Britzi, Malka; Friedman, Shmulik; Miron, Joshua; Solomon, Ran; Cuneah, Olga; Shimshoni, Jakob A.; Soback, Stefan; Ashkenazi, Rina; Armer, Sima; Shlosberg, Alan

    2013-01-01

    The potent hepatotoxin and carcinogen aflatoxin B1 (AFB1) is a common mycotoxin contaminant of grains used in animal feeds. Aflatoxin M1 (AFM1) is the major metabolite of AFB1 in mammals, being partially excreted into milk, and is a possible human carcinogen. The maximum permitted concentration of AFM1 in cows’ milk is 0.05 μg/kg in Israel and the European Union. Since milk yield and the carry-over of AFB1 in the feed to AFM1 in the milk are highly correlated, it was considered important to determine the AFM1 carry-over in Israeli-Holstein dairy cows, distinguished by world record high milk production. Twelve such cows were used to determine AFM1 carry-over following daily oral administration of feed containing ~86 μg AFB1 for 7 days. The mean carry-over rate at steady-state (Days 3–7) was 5.8% and 2.5% in mid-lactation and late-lactation groups, respectively. The carry-over appears to increase exponentially with milk yield and could be described by the equation: carry-over% = 0.5154 e0.0521 × milk yield, with r2 = 0.6224. If these data truly reflect the carry-over in the national Israeli dairy herd, the maximum level of AFB1 in feed should not exceed 1.4 μg/kg, a value 3.6 times lower than the maximum residue level currently applied in Israel. PMID:23325299

  5. Organophilic treatments of bentonite increase the adsorption of aflatoxin B1 and protect stem cells against cellular damage.

    PubMed

    Nones, Janaína; Nones, Jader; Poli, Anicleto; Trentin, Andrea Gonçalves; Riella, Humberto Gracher; Kuhnen, Nivaldo Cabral

    2016-09-01

    Bentonite clays exhibit high adsorptive capacity for contaminants, including aflatoxin B1 (AFB1), a mycotoxin responsible for causing severe toxicity in several species including pigs, poultry and man. Organophilic treatments is known to increase the adsorption capacity of bentonites, and the primary aim of this study was to evaluate the ability of Brazilian bentonite and two organic salts - benzalkonium chloride (BAC) and cetyltrimethylammonium bromide (CTAB) to adsorb AFB1. For this end, 2(2) factorial designs were used in order to analyze if BAC or CTAB was able to increase AFB1 adsorption when submitted in different temperature and concentration. Both BAC and CTAB treatment (at 30°C and 2% of salt concentration) were found to increase the adsorption of AFB1 significantly compared with untreated bentonite. After organophilic bentonite treatments with BAC or CTAB, a vibration of CH stretch (2850 and 2920cm(-1)) were detected. A frequency of the SiO stretch (1020 and 1090cm(-1)) was changed by intercalation of organic cation. Furthermore, the interlayer spacing of bentonite increases to 1.23nm (d001 reflection at 2θ=7.16) and 1.22 (d001 reflection at 2θ=7.22) after the addition of BAC and CTAB, respectively. Another aim of the study was to observe the effects of these two bentonite salts in neural crest stem cell cultures. The two materials that were created by organophilic treatments were not found to be toxic to stem cells. Furthermore the results indicate that the two materials tested may protect the neural crest stem cells against damage caused by AFB1.

  6. Filtration-based tyramide amplification technique--a new simple approach for rapid detection of aflatoxin B1.

    PubMed

    Saha, Debjani; Acharya, Debopam; Roy, Dipika; Dhar, Tarun K

    2007-02-01

    The catalyzed reporter deposition (CARD) method of signal amplification, also called "tyramide signal amplification", has been used in immunoassays not only to increase sensitivity but also to reduce assay time. The current approach to tyramide amplification in immunoassays involves slow incubation with agitation. In this paper we describe new filtration-based tyramide amplification and substrate visualization techniques. Compared with the standard method, this new approach greatly enhances spot intensities in membrane immunoassay and reduces biotinylated tyramide (B-T) and substrate consumption approximately fiftyfold, without loss of specificity. An improved test device and a cost-effective method for preparation of membranes for Super-CARD amplification have also been developed. The techniques have been used for rapid detection of aflatoxin B(1) (AFB(1)) in a variety of foodstuffs with a detection limit of 12.5 microg kg(-1). The assay procedure involves sequential addition of standards or sample, AFB(1)-horseradish peroxidase (HRP) conjugate, B-T, avidin-HRP, and substrate solution over anti-AFB(1) antibody-spotted zones of the membrane surface. The method saves time, improves reproducibility, eliminates many washing steps and avoids manipulation of the membranes between the different steps, while maintaining the sensitivity of the standard method. Average recoveries from different non-infected food samples spiked with AFB(1) at concentrations from 25 to 100 mg kg(-1) were between 95 and 105%. AFB(1) results obtained on different days for Aspergillus parasiticus infection of corn and groundnut samples correlated well with estimates obtained by HPLC.

  7. Deciphering the Anti-Aflatoxinogenic Properties of Eugenol Using a Large-Scale q-PCR Approach

    PubMed Central

    Caceres, Isaura; El Khoury, Rhoda; Medina, Ángel; Lippi, Yannick; Naylies, Claire; Atoui, Ali; El Khoury, André; Oswald, Isabelle P.; Bailly, Jean-Denis; Puel, Olivier

    2016-01-01

    Produced by several species of Aspergillus, Aflatoxin B1 (AFB1) is a carcinogenic mycotoxin contaminating many crops worldwide. The utilization of fungicides is currently one of the most common methods; nevertheless, their use is not environmentally or economically sound. Thus, the use of natural compounds able to block aflatoxinogenesis could represent an alternative strategy to limit food and feed contamination. For instance, eugenol, a 4-allyl-2-methoxyphenol present in many essential oils, has been identified as an anti-aflatoxin molecule. However, its precise mechanism of action has yet to be clarified. The production of AFB1 is associated with the expression of a 70 kB cluster, and not less than 21 enzymatic reactions are necessary for its production. Based on former empirical data, a molecular tool composed of 60 genes targeting 27 genes of aflatoxin B1 cluster and 33 genes encoding the main regulatory factors potentially involved in its production, was developed. We showed that AFB1 inhibition in Aspergillus flavus following eugenol addition at 0.5 mM in a Malt Extract Agar (MEA) medium resulted in a complete inhibition of the expression of all but one gene of the AFB1 biosynthesis cluster. This transcriptomic effect followed a down-regulation of the complex composed by the two internal regulatory factors, AflR and AflS. This phenomenon was also influenced by an over-expression of veA and mtfA, two genes that are directly linked to AFB1 cluster regulation. PMID:27128940

  8. Effects of Milk Yield, Feed Composition, and Feed Contamination with Aflatoxin B1 on the Aflatoxin M1 Concentration in Dairy Cows’ Milk Investigated Using Monte Carlo Simulation Modelling

    PubMed Central

    van der Fels-Klerx, H. J.; Camenzuli, Louise

    2016-01-01

    This study investigated the presence of aflatoxin M1 (AfM1) in dairy cows’ milk, given predefined scenarios for milk production, compound feed (CF) contamination with aflatoxin B1 (AfB1), and inclusion rates of ingredients, using Monte Carlo simulation modelling. The model simulated a typical dairy farm in the Netherlands. Six different scenarios were considered, based on two lactation and three CF composition scenarios. AfB1 contamination of the CF was based on results from the Dutch national monitoring programme for AfB1 in feed materials from 2000 until 2010. Monitoring data from feed materials used in CF production for dairy cattle in the Netherlands were used. Additionally, AfB1 contamination data from an incident in maize in 2013 were used. In each scenario, five different transfer equations of AfB1 from feed to AfM1 in the milk were used, and 1000 iterations were run for each scenario. The results showed that under these six scenarios, the weekly farm concentration of AfM1 in milk was above the EC threshold in less than 1% of the iterations, with all five transfer equations considered. However, this increased substantially in weeks when concentrations from the contaminated maize batch were included, and up to 28.5% of the iterations exceeded the EC threshold. It was also observed that an increase in the milk production had a minimal effect on the exceedance of the AfM1 threshold due to an apparent dilution effect. Feeding regimes, including the composition of CF and feeding roughages of dairy cows, should be carefully considered based on the potential AfM1 contamination of the farm’s milk. PMID:27735836

  9. Non-Linear Relationships between Aflatoxin B1 Levels and the Biological Response of Monkey Kidney Vero Cells

    PubMed Central

    Rasooly, Reuven; Hernlem, Bradley; He, Xiaohua; Friedman, Mendel

    2013-01-01

    Aflatoxin-producing fungi contaminate food and feed during pre-harvest, storage and processing periods. Once consumed, aflatoxins (AFs) accumulate in tissues, causing illnesses in animals and humans. Most human exposure to AF seems to be a result of consumption of contaminated plant and animal products. The policy of blending and dilution of grain containing higher levels of aflatoxins with uncontaminated grains for use in animal feed implicitly assumes that the deleterious effects of low levels of the toxins are linearly correlated to concentration. This assumption may not be justified, since it involves extrapolation of these nontoxic levels in feed, which are not of further concern. To develop a better understanding of the significance of low dose effects, in the present study, we developed quantitative methods for the detection of biologically active aflatoxin B1 (AFB1) in Vero cells by two independent assays: the green fluorescent protein (GFP) assay, as a measure of protein synthesis by the cells, and the microculture tetrazolium (MTT) assay, as a measure of cell viability. The results demonstrate a non-linear dose-response relationship at the cellular level. AFB1 at low concentrations has an opposite biological effect to higher doses that inhibit protein synthesis. Additional studies showed that heat does not affect the stability of AFB1 in milk and that the Vero cell model can be used to determine the presence of bioactive AFB1 in spiked beef, lamb and turkey meat. The implication of the results for the cumulative effects of low amounts of AFB1 in numerous foods is discussed. PMID:23949006

  10. Effect of temperature and water activity on gene expression and aflatoxin biosynthesis in Aspergillus flavus on almond medium.

    PubMed

    Gallo, Antonia; Solfrizzo, Michele; Epifani, Filomena; Panzarini, Giuseppe; Perrone, Giancarlo

    2016-01-18

    Almonds are among the commodities at risk of aflatoxin contamination by Aspergillus flavus. Temperature and water activity are the two key determinants in pre and post-harvest environments influencing both the rate of fungal spoilage and aflatoxin production. Varying the combination of these parameters can completely inhibit or fully activate the biosynthesis of aflatoxin, so it is fundamental to know which combinations can control or be conducive to aflatoxin contamination. Little information is available about the influence of these parameters on aflatoxin production on almonds. The objective of this study was to determine the influence of different combinations of temperature (20 °C, 28 °C, and 37 °C) and water activity (0.90, 0.93, 0.96, 0.99 aw) on growth, aflatoxin B1 (AFB1) production and expression of the two regulatory genes, aflR and aflS, and two structural genes, aflD and aflO, of the aflatoxin biosynthetic cluster in A. flavus grown on an almond medium solidified with agar. Maximum accumulation of fungal biomass and AFB1 production was obtained at 28 °C and 0.96 aw; no fungal growth and AFB1 production were observed at 20 °C at the driest tested conditions (0.90 and 0.93 aw). At 20° and 37 °C AFB1 production was 70-90% lower or completely suppressed, depending on aw. Reverse transcriptase quantitative PCR showed that the two regulatory genes (aflR and aflS) were highly expressed at maximum (28 °C) and minimum (20 °C and 37 °C) AFB1 production. Conversely the two structural genes (aflD and aflO) were highly expressed only at maximum AFB1 production (28 °C and 0.96-0.99 aw). It seems that temperature acts as a key factor influencing aflatoxin production which is strictly correlated to the induction of expression of structural biosynthesis genes (aflD and aflO), but not to that of aflatoxin regulatory genes (aflR and aflS), whose functional products are most likely subordinated to other regulatory processes acting at post-translational level

  11. DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B1 Adduct

    PubMed Central

    2016-01-01

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus, is oxidized by cytochrome P450 enzymes to aflatoxin B1-8,9-epoxide, which alkylates DNA at N7-dG. Under basic conditions, this N7-dG adduct rearranges to yield the trans-8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy aflatoxin B1 (AFB1–FAPY) adduct. The AFB1–FAPY adduct exhibits geometrical isomerism involving the formamide moiety. NMR analyses of duplex oligodeoxynucleotides containing the 5′-XA-3′, 5′-XC-3′, 5′-XT-3′, and 5′-XY-3′ sequences (X = AFB1–FAPY; Y = 7-deaza-dG) demonstrate that the equilibrium between E and Z isomers is controlled by major groove hydrogen bonding interactions. Structural analysis of the adduct in the 5′-XA-3′ sequence indicates the preference of the E isomer of the formamide group, attributed to formation of a hydrogen bond between the formyl oxygen and the N6 exocyclic amino group of the 3′-neighbor adenine. While the 5′-XA-3′ sequence exhibits the E isomer, the 5′-XC-3′ sequence exhibits a 7:3 E:Z ratio at equilibrium at 283 K. The E isomer is favored by a hydrogen bond between the formyl oxygen and the N4-dC exocyclic amino group of the 3′-neighbor cytosine. The 5′-XT-3′ and 5′-XY-3′ sequences cannot form such a hydrogen bond between the formyl oxygen and the 3′-neighbor T or Y, respectively, and in these sequence contexts the Z isomer is favored. Additional equilibria between α and β anomers and the potential to exhibit atropisomers about the C5–N5 bond do not depend upon sequence. In each of the four DNA sequences, the AFB1–FAPY adduct maintains the β deoxyribose configuration. Each of these four sequences feature the atropisomer of the AFB1 moiety that is intercalated above the 5′-face of the damaged guanine. This enforces the Ra axial conformation for the C5–N5 bond. PMID:25587868

  12. DNA Sequence Modulates Geometrical Isomerism of the trans-8,9- Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)- 9-hydroxy Aflatoxin B1 Adduct.

    PubMed

    Li, Liang; Brown, Kyle L; Ma, Ruidan; Stone, Michael P

    2015-02-16

    Aflatoxin B(1) (AFB(1)), a mycotoxin produced by Aspergillus flavus, is oxidized by cytochrome P450 enzymes to aflatoxin B(1)-8,9-epoxide, which alkylates DNA at N7-dG. Under basic conditions, this N7-dG adduct rearranges to yield the trans-8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy aflatoxin B(1) (AFB(1)−FAPY) adduct. The AFB(1)−FAPY adduct exhibits geometrical isomerism involving the formamide moiety. NMR analyses of duplex oligodeoxynucleotides containing the 5′-XA-3′, 5′-XC-3′, 5′-XT-3′, and 5′-XY-3′ sequences (X = AFB(1)−FAPY; Y = 7-deaza-dG)demonstrate that the equilibrium between E and Z isomers is controlled by major groove hydrogen bonding interactions.Structural analysis of the adduct in the 5′-XA-3′ sequence indicates the preference of the E isomer of the formamide group,attributed to formation of a hydrogen bond between the formyl oxygen and the N(6) exocyclic amino group of the 3′-neighboradenine. While the 5′-XA-3′ sequence exhibits the E isomer, the 5′-XC-3′ sequence exhibits a 7:3 E:Z ratio at equilibrium at 283K. The E isomer is favored by a hydrogen bond between the formyl oxygen and the N(4)-dC exocyclic amino group of the 3′-neighbor cytosine. The 5′-XT-3′ and 5′-XY-3′ sequences cannot form such a hydrogen bond between the formyl oxygen and the 3′-neighbor T or Y, respectively, and in these sequence contexts the Z isomer is favored. Additional equilibria between α and β anomers and the potential to exhibit atropisomers about the C5−N(5) bond do not depend upon sequence. In each of the four DNA sequences, the AFB(1)−FAPY adduct maintains the β deoxyribose configuration. Each of these four sequences feature the atropisomer of the AFB(1) moiety that is intercalated above the 5′-face of the damaged guanine. This enforces the Ra axialc onformation for the C5−N(5) bond.

  13. Effect of γ irradiation on fungal load and aflatoxins reduction in red chillies

    NASA Astrophysics Data System (ADS)

    Iqbal, Shahzad Zafar; Bhatti, Ijaz Ahmad; Asi, Muhammad Rafique; Zuber, Mohammad; Shahid, Muhammad; Parveen, Ishrat

    2013-01-01

    Chillies are a very important cash crop of Pakistan. The effects of gamma irradiation on microbial load, aflatoxin B1 (AFB1) and total aflatoxins have been studied in chillies samples, collected from different districts of Punjab, Pakistan. Aflatoxins were analyzed using HPLC equipped with a fluorescence detector. The results revealed that among the Aspergillus species isolated, those belonging to section parasiticus were predominant. Gamma radiations of doses 2, 4 and 6 kGy were employed on fungi and chilli samples. The results have demonstrated that the dose of 6 kGy reduced the fungal load by 5 logs. Furthermore, 6 kGy reduced the level of AFB1 and total AFs in ground and whole chillies by 1-2 logs (α < 0.05).

  14. Survey of Aspergillus section Flavi and aflatoxin B(1) in brewer's grain used as pig feedstuff in Córdoba, Argentina.

    PubMed

    Asurmendi, P; Barberis, C; Dalcero, A; Pascual, L; Barberis, L

    2013-02-01

    Brewing industry by-products are important animal feedstuff alternatives for local swine producers in Córdoba, Argentina. The high content of nutrients makes these by-products vulnerable to bacterial and fungal contamination. The objectives of the present study were (1) to determine the presence of Aspergillus section Flavi in brewer's grain used to feed pigs and (2) to evaluate the incidence of aflatoxin B(1) in the substrate. Total fungal count of most samples exceeded the levels proposed as feed quality limits, and most Aspergillus section Flavi strains found were able to produce high amounts of AFB(1) in vitro. However, the incidence of AFB(1) was low. The presence of contamination by aflatoxicogenic species in feedstuff might affect the productivity of swine producers and indirectly represents a public health issue.

  15. Screening of new chemopreventive compounds from Digitalis purpurea.

    PubMed

    Lee, J Y; Woo, E; Kang, K W

    2006-04-01

    Chemopreventive agents induce a battery of genes whose protein products can protect cells from chemical-induced carcinogenesis. In this study, we isolated four different glycosides (1 acteoside; 2 purpureaside A; 3 calceolarioside B; and 4, plantainoside D) from the leaves of Digitalis purpurea and studied their abilities to induce glutathione S-transferase (GST) and their protective efficiencies against aflatoxin B1-induced cytotoxicity in H4IIE cells. Of these four glycosides, acteoside significantly inhibited the cytotoxicity induced by aflatoxin B1 (AFB1) and also selectively increased GSTalpha protein levels. Reporter gene analysis using an antioxidant response element (ARE) containing construct and subcellular fractionation assays, revealed that GSTalpha induction by acteoside might be associated with Nrf2/ARE activation. The results suggest that acteoside possesses a potent hepatoprotective effect against AFB1 and that it can be applied as a potential chemopreventive agent.

  16. Screening antimutagenic and antiproliferative properties of extracts isolated from Jackfruit pulp (Artocarpus heterophyllus Lam).

    PubMed

    Ruiz-Montañez, G; Burgos-Hernández, A; Calderón-Santoyo, M; López-Saiz, C M; Velázquez-Contreras, C A; Navarro-Ocaña, A; Ragazzo-Sánchez, J A

    2015-05-15

    The present focused on the study of the antimutagenic and antiproliferative potential of pulp Jackfruit (Artocarpus heterophyllus Lam) extract, using Salmonella typhimurium tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line M12.C3.F6 (murine B-cell lymphoma), respectively. Jackfruit pulp extract was sequentially fractionated by chromatography (RP-HPLC) and each fraction was tested for antimutagenic and antiproliferative activities. The organic extracts obtained from Jackfruit pulp reduced the number of revertants caused by aflatoxin B1 (AFB1) and proliferation of cells M12.C3.F6; a dose-response relationship was showed. Sequential RP-HPLC fractionation of the active extracts produced both antimutagenic and/or antiproliferative fractions. These results suggested that the Jackfruit contained compounds with chemoprotective properties to reduce the mutagenicity of AFB1, also proliferation of a cancer cell line.

  17. The origin of the Japanese race based on genetic markers of immunoglobulin G

    PubMed Central

    Matsumoto, Hideo

    2009-01-01

    This review addresses the distribution of genetic markers of immunoglobulin G (Gm) among 130 Mongoloid populations in the world. These markers allowed the populations to be clearly divided into 2 groups, the northern and southern groups. The northern group is characterized by high frequencies of 2 marker genes, ag and ab3st, and an extremely low frequency of the marker gene afb1b3; and the southern group, in contrast, is indicated by a remarkably high frequency of afb1b3 and low frequencies of ag and ab3st. Based on the geographical distribution of the markers and gene flow of Gm ag and ab3st (northern Mongoloid marker genes) from northeast Asia to the Japanese archipelago, the Japanese population belongs basically to the northern Mongoloid group and is thus suggested to have originated in northeast Asia, most likely in the Baikal area of Siberia. PMID:19212099

  18. Nonlinear Dynamics and Quantum Transport in Small Systems

    DTIC Science & Technology

    2012-02-22

    microelectromechanical (MEM) and nanoelectromechanical (NEM) sys- tems; • Electronic transport in graphene systems. 2 Accomplishments and New Findings 2.1 Nonlinear...generators. All these were collaborative works with Dr. David Dietz from AFRL at Kirtland AFB. 2.2 Electronic transport in graphene systems There is...tremendous interest in graphene recently due to its potential applications in nano-scale electronic devices and circuits. It is possible that future

  19. Environmental Assessment: Construct Fuel Bowser Storage Area Install Underground Storage Tank, Security Fencing, Lighting Construct Bowser Open Storage Pavement at Grand Forks AFB, North Dakota

    DTIC Science & Technology

    2004-10-01

    Air Force Base has pro- posed the construction of an underground fuel-water recovery storage tank with SeGU- D We rity fencing and light- Is, Sec...your ad. Second or Third year Plumbing Apprentice. We are looking for a second or. third year plumbing apprentice to join our work force. Need...storage tank with secu- rity fencing and light- Ing and a paved open storage area for fuel bowsers on Grand Forks AFB. 2 - RESERVED We Fest lawn

  20. Minuteman III Motor-Generator Bearing Grease Replacement

    DTIC Science & Technology

    2013-07-01

    13. SUPPLEMENTARY NOTES 14. ABSTRACT The study was initiated to develop/find a lubricating grease (s) and preserve oil to replace Texaco Multifak...AFB2 grease, Hill AFB is currently seeking its replacement. As a part of the test plan, nine lubricating greases and five preservative oils used in the...release 12b. DISTRIBUTION CODE 13. ABSTRACT (Maximum 200 words) The study was initiated to develop/find a lubricating grease (s) and preserve oil to

  1. Effect of supplementation of fermented milk drink containing probiotic Lactobacillus casei Shirota on the concentrations of aflatoxin biomarkers among employees of Universiti Putra Malaysia: a randomised, double-blind, cross-over, placebo-controlled study.

    PubMed

    Mohd Redzwan, Sabran; Abd Mutalib, Mohd Sokhini; Wang, Jia-Sheng; Ahmad, Zuraini; Kang, Min-Su; Abdul Rahman, Nurul 'Aqilah; Nikbakht Nasrabadi, Elham; Jamaluddin, Rosita

    2016-01-14

    Human exposure to aflatoxin is through the diet, and probiotics are able to bind aflatoxin and prevent its absorption in the small intestine. This study aimed to determine the effectiveness of a fermented milk drink containing Lactobacillus casei Shirota (LcS) (probiotic drink) to prevent aflatoxin absorption and reduce serum aflatoxin B1-lysine adduct (AFB1-lys) and urinary aflatoxin M1 concentrations. The present study was a randomised, double-blind, cross-over, placebo-controlled study with two 4-week intervention phases. In all, seventy-one subjects recruited from the screening stage were divided into two groups--the Yellow group and the Blue group. In the 1st phase, one group received probiotic drinks twice a day and the other group received placebo drinks. Blood and urine samples were collected at baseline, 2nd and 4th week of the intervention. After a 2-week wash-out period, the treatments were switched between the groups, and blood and urine samples were collected at the 6th, 8th and 10th week (2nd phase) of the intervention. No significant differences in aflatoxin biomarker concentrations were observed during the intervention. A within-group analysis was further carried out. Aflatoxin biomarker concentrations were not significantly different in the Yellow group. Nevertheless, ANOVA for repeated measurements indicated that AFB1-lys concentrations were significantly different (P=0·035) with the probiotic intervention in the Blue group. The 2nd week AFB1-lys concentrations (5·14 (SD 2·15) pg/mg albumin (ALB)) were significantly reduced (P=0·048) compared with the baseline (6·24 (SD 3·42) pg/mg ALB). Besides, the 4th week AFB1-lys concentrations were significantly lower (P<0·05) with probiotic supplementation than with the placebo. Based on these findings, a longer intervention study is warranted to investigate the effects of continuous LcS consumption to prevent dietary aflatoxin exposure.

  2. Monitoring of individual human exposure to aflatoxins (AF) and N-nitrosamines (NNO) by immunoassays

    SciTech Connect

    Wild, C.P.; Umbenhauer, D.; Chapot, B.; Montesano, R.

    1986-01-01

    Highly sensitive immunoassays have been used to quantitate aflatoxins (AF) and N-nitrosamines (NNO) in human body fluids and tissues, respectively. This approach was taken in order to quantitate environmental exposure to these agents at an individual level to facilitate the investigation of their role in the etiology of human cancer. In order to analyse AF in human urine, an immunopurification step has been developed by using AF-specific antibody bound to AH-Sepharose 4B gel in a small (4-ml gel volume) affinity column prior to enzyme-linked immunosorbent assay (ELISA). The ELISA can be used to quantitate aflatoxin B1 (AFB1) over the range 0.01 ng/ml to 10 ng/ml and the assay system has been validated by using human urine samples spiked with AFB1 over this concentration range. In addition, 29 urine samples from the Philippines have been analyzed and found to contain a range of levels from zero to 4.25 ng/ml AFB1 equivalent with a mean of 0.875 ng/ml. This compared with a mean of 0.066 ng/ml AFB1 equivalent in samples from France. Radioimmunoassay of O6-methyldeoxyguanosine (O6-medG) has been performed on human esophageal and cardiac stomach mucosal DNA from tissue samples obtained during surgery in Linxian County, People's Republic of China, an area of high risk for both esophageal and stomach cancer. Using the methodology described and having 1 mg of hydrolyzed DNA allows the detection of approximately 25 fmol O6medG per mg DNA.

  3. Ultraviolet irradiation of monkey cells enhances the repair of DNA adducts in alpha DNA

    SciTech Connect

    Leadon, S.A.; Hanawalt, P.C.

    1984-11-01

    Excision repair of bulky adducts in alpha DNA of African green monkey cells has previously been shown to be deficient relative to that in the overall genome. We have found that u.v. irradiation of these cells results in the enhanced removal of both aflatoxin B1 (AFB1) and acetylaminofluorene (AAF) adducts from the alpha DNA sequences without affecting repair in the bulk of the DNA. The degree of enhanced removal of AFB1 is dependent upon the u.v. dose and the time interval between irradiation and AFB1 treatment. The u.v. enhancement is not inhibited by cycloheximide. Exposure of the cells to dimethylsulfate or gamma-rays does not affect AFB1 adduct repair. The formation and removal of N-acetoxy-2-acetylaminofluorene (NA-AAF) adducts from alpha and bulk DNA was studied in detail. A higher initial level of the acetylated C8 adduct of guanine was found in alpha DNA than in bulk DNA. Although both the acetylated and deacetylated C8 adducts were removed from the two DNA species, the level of repair was significantly greater in the bulk DNA. Irradiation of cells with u.v. prior to treatment with NA-AAF enhanced the removal of both adducts from alpha DNA with little or no effect on repair in bulk DNA. We conclude that the presence of u.v. photoproducts or some intermediate in their processing alters the chromatin structure of alpha DNA thereby rendering bulky adducts accessible to repair enzymes. In addition, the differential formation and repair of AAF adducts in alpha DNA compared with that in the bulk of the genome supports the hypothesis of an altered chromatin structure for alpha domains.

  4. Novel glucometer-based immunosensing strategy suitable for complex systems with signal amplification using surfactant-responsive cargo release from glucose-encapsulated liposome nanocarriers.

    PubMed

    Tang, Juan; Huang, Yapei; Liu, Huiqiong; Zhang, Cengceng; Tang, Dianping

    2016-05-15

    Methods based on surfactant-responsive controlled release systems of cargoes from nanocontainers have been developed for bioanalytical applications, but most were utilized for drug delivery and a few reports were focused on immunoassays. Herein we design an in situ amplified immunoassay protocol for high-efficient detection of aflatoxins (aflatoxin B1, AFB1 used in this case) based on surfactant-responsive cargo release from glucose-encapsulated liposome nanocarriers with sensitivity enhancement. Initially, biotinylated liposome nanocarrier encapsulated with glucose was synthesized using a reverse-phase evaporation method. Thereafter, the nanocarrier was utilized as the signal-generation tag on capture antibody-coating microplate through classical biotin-avidin linkage after reaction with biotinylated detection antibody. Upon addition of buffered surfactant (1X PBS-Tween 20 buffer) into the medium, the surfactant immediately hydrolyzed the conjugated liposome, and released the encapsulated glucose from the nanocarriers, which could be quantitatively determined by using a low-cost personal glucometer (PGM). The detectable signal increased with the increment of target analyte. Under the optimal conditions, the assay could allow PGM detection toward target AFB1 as low as 0.6 pg mL(-1) (0.6 ppt). Moreover, the methodology also showed good reproducibility and high specificity toward target AFB1 against other mycotoxins and proteins, and was applicable for quantitatively monitoring target AFB1 in the complex systems, e.g., naturally contaminated/spiked peanut samples and serum specimens, with the acceptable results. Taking these advantages of simplification, low cost, universality and sensitivity, our design provides a new horizon for development of advanced immunoassays in future point-of-care testing.

  5. Intrusive and Non-Intrusive Instruction in Dynamic Skill Training.

    DTIC Science & Technology

    1981-10-01

    Bachrach Environmental Stress Program Center I Dr. Lloyd Hitchcock Naval Medical Research Institute Human Factors Engineering Bethesda, MD 20014 Division...22217 Washington, DC 20350 5 Personnel & Training Research Programs 1 Dr. Alfred F. Smode (Code 458) Training Analysis & Evaluation Group Office of... Alfred R. Fregly Arlington, VA 22217 AFOSR/NL, Bldg. 410] Bolling AFB 1 DR. A.L. SLAFKOSKY Washington, DC 20332 SCIENTIFIC ADVISOR (CODE RD-i) HO

  6. Aflatoxin B1 contamination in feed from Puglia and Basilicata regions (Italy): 5 years monitoring data.

    PubMed

    Vita, V; Clausi, M T; Franchino, C; De Pace, R

    2016-11-01

    During a 5-year period from 2010 to 2014, n = 919 samples of feed and raw materials were analyzed for aflatoxin B1 (AFB1) contamination using accredited ELISA screening methods. Only 0.76 % of these samples were non-compliant with maximum levels set by the European Union Regulation 32/2002. Non-compliant samples were mainly from the province of Bari (n = 3 samples, mean AFB1 value 7.03 μg/kg), although the highest AFB1 levels were found in two samples from the provinces of Foggia and Brindisi, at 32.6 ± 3.6 μg/kg and 31.0 ± 4.0 μg/kg, respectively. Mean AFB1 levels in samples contaminated but compliant with the limits ranged from 1.4 to 2.2 μg/kg. Considering the great importance of climate conditions in mycotoxins production, during crops production and during the critical phases of materials storage and/or transport, to better understand the variability in contamination levels, the analytical results were reviewed in term of temperature and relative environmental humidity in the sampling areas. Correlations between aflatoxin B1 levels in feed and these climate factors might explain seasonal and annual variations in contamination levels. The data from the present study provide useful suggestions for the organization of targeted monitoring plans and the protection of consumers, as well as for improvement in the quality standards of zootechnological activities and feed industry.

  7. Characterization of aflatoxigenic and non-aflatoxigenic Aspergillus flavus isolates from pistachio.

    PubMed

    Hua, Sui Sheng T; McAlpin, Cesaria E; Chang, Perng-Kuang; Sarreal, Siov Bouy L

    2012-02-01

    Pistachio is a popular snack food. Aflatoxin contamination of pistachio nuts is a serious problem for many producing countries. The development of biological control methods based on ecological parameters is an environmentally friendly approach. Thirty-eight Aspergillus flavus isolates collected from a pistachio orchard in California (CA) were analyzed for production of aflatoxin (AF), cyclopiazonic acid (CPA), vegetative compatibility groups (VCGs), and mating types. All aflatoxigenic isolates produced both AFB1 and CPA. The most toxigenic one was CA28 which produced 164 μg AFB1 per 5 ml PDA fungal culture and small sclerotia (S strain, sclertoium size less than 400 μm). The other aflatoxigenic strains produce AFB1 ranging from 1.2 μg to 80 μg per 5 ml fungal culture. Twenty-one percent of the CA isolates produced AFB1, 84% produced CPA and half formed sclerotia on at least one of three tested media. The 38 CA isolates formed 26 VCGs, 6 of which had two or more isolates and 20 contained single isolates. The S strain isolates belong to 4 different VCGs. Genomic profiling by a retrotransposon DNA probe revealed fingerprint patterns that were highly polymorphic. The predicted VCGs (Pred-VCGs) based on a similarity coefficient >80% matched the VCGs of multiple isolates determined by complementation. All isolates within a VCG had the same mating-type gene of either MAT1-1 or MAT1-2. Uncorrected and VCG-corrected MAT1-1 and MAT1-2 among the isolates were equally distributed.

  8. Proceedings of the Vesicant Workshop, February 1987

    DTIC Science & Technology

    1987-12-01

    Rapid detection and decontamination, therefore, become essential in order to permit reduction of MOPP levels. The medical intensity inherent in vesicant...I ~ i Y I " Paipirueister Sum$ary of Presentation I Induction of Glutathione S-Transferase Enhances Detoxification of Aflatoxin I B Control <®, RzW...profiles are shown for aflatoxin B (AFB ) adducts of rat liver DNA. Rats fed 3 control or ethoxyquin-sup~lemented diets were gavaged with I H]AFB 1

  9. Inhibitory effects of Ephedra major Host on Aspergillus parasiticus growth and aflatoxin production.

    PubMed

    Bagheri-Gavkosh, Shahrokh; Bigdeli, Mohsen; Shams-Ghahfarokhi, Masoomeh; Razzaghi-Abyaneh, Mehdi

    2009-11-01

    This study was undertaken to evaluate the effect of Ephedra major Host, an important medicinal plant with various biological activities, on growth and aflatoxin (AF) production by Aspergillus parasiticus NRRL 2999. The fungus was cultured in yeast extract-sucrose (YES) broth, a conductive medium that supports AF production, in the presence of various concentrations of essential oil (EO), hexanic and methanolic extracts of plant aerial parts, fruits, and roots using microbioassay technique. After incubating for 96 h at 28 degrees C in static conditions, mycelial dry weight was determined as an index of fungal growth, and aflatoxin B(1) (AFB(1)) was measured using HPLC technique. Based on the obtained results, EO of plant aerial parts significantly inhibited fungal growth at the highest concentration of 1000 microg/ml without any obvious effect on AFB(1) production at all concentrations used. Among plant extracts tested, only methanolic extract of aerial parts and roots were found to inhibit fungal growth and AFB(1) production dose-dependently with an IC(50) value of 559.74 and 3.98 microg/ml for AFB(1), respectively. Based on the GC/MS data, the major components of E. major EO were bis (2-ethylhexyl) phthalate (42.48%), pentacosane (20.94%), docosane (14.64%), citronellol (5.15%), heptadecan (4.41%), cis-3-Hexen-1-ol benzoate (4.07%), and 7-Octen-2-ol (3.25%). With respect to the potent inhibition of fungal growth and AF production by E. major, this plant may be useful in protecting crops from both toxigenic fungal growth and AF contamination.

  10. Aflatoxin Toxicity Reduction in Feed by Enhanced Binding to Surface-Modified Clay Additives

    PubMed Central

    Jaynes, William F.; Zartman, Richard E.

    2011-01-01

    Animal feeding studies have demonstrated that clay additives, such as bentonites, can bind aflatoxins in ingested feed and reduce or eliminate the toxicity. Bentonite deposits are found throughout the world and mostly consist of expandable smectite minerals, such as montmorillonite. The surfaces of smectite minerals can be treated with organic compounds to create surface-modified clays that more readily bind some contaminants than the untreated clay. Montmorillonites treated with organic cations, such as hexadecyltrimethylammonium (HDTMA) and phenyltrimethylammonium (PTMA), more effectively remove organic contaminants, such as benzene and toluene, from water than untreated clay. Similarly, montmorillonite treated with PTMA (Kd = 24,100) retained more aflatoxin B1 (AfB1) from aqueous corn flour than untreated montmorillonite (Kd = 944). Feed additives that reduced aflatoxin toxicity in animal feeding studies adsorbed more AfB1 from aqueous corn flour than feed additives that were less effective. The organic cations HDTMA and PTMA are considered toxic and would not be suitable for clay additives used in feed or food, but other non-toxic or nutrient compounds can be used to prepare surface-modified clays. Montmorillonite (SWy) treated with choline (Kd = 13,800) and carnitine (Kd = 3960) adsorbed much more AfB1 from aqueous corn flour than the untreated clay (Kd = 944). A choline-treated clay prepared from a reduced-charge, high-charge montmorillonite (Kd = 20,100) adsorbed more AfB1 than the choline-treated high-charge montmorillonite (Kd = 1340) or the untreated montmorillonite (Kd = 293). Surface-modified clay additives prepared using low-charge smectites and nutrient or non-toxic organic compounds might be used to more effectively bind aflatoxins in contaminated feed or food and prevent toxicity. PMID:22069725

  11. Wastewater and Hazardous Waste Survey, Homestead AFB Florida.

    DTIC Science & Technology

    1988-03-01

    Hexachloroexxhydro-exo,exo-dimethanonapthalene Hexamethyltetraphosphate Hydrazinecarbothioam ide Hydrazine methyl Hydrocyanic acid Hydrogen cyanide Hydrogen...characteristic hazardous waste (EP Toxicity) analysis on neutralized battery acid . (5) Drums and bowsers at waste storage sites should be secured. (6) Paint...neutralized battery acid . In fact, 95% of all wastes are included in the first six categories. Table 7: Categories of Waste on Homestead AFB 1 Category

  12. Inhibitory Effects of Silver Nanoparticles on Growth and Aflatoxin B1 Production by Aspergillus Parasiticus

    PubMed Central

    Mousavi, Seyyed Amin Ayatollahi; Pourtalebi, Somayyeh

    2015-01-01

    Background: Aflatoxins (AFs) are secondary hazardous fungal metabolites that are produced by strains of some Aspergillus species on food and feedstuffs. Aflatoxin B1 (AFB1) is one of the most important AF with high toxicity. Prevention of AF production and their elimination from food products is a matter of importance for many researchers in the last decades. Nanomaterials applications in medical science have been widely studied in the recent years. Most of existing researches seek the effect of nanoparticles on bacteria, fungi, and viruses. The aim of this study was to determine the effects of silver nanoparticles (AgNPs) on growth and AFB1 production of AF-producing Aspergillus parasiticus. Methods: A parasiticus was inoculated (106 conidia per ml of medium) to potato dextrose broth (PDB) medium and then AgNPs was added and incubated with shaking at 130 rpm and 28°C for 7 days. AF was assayed by high performance liquid chromatography (HPLC). Microbiological assay (MBA) on microplates contained potato dextrose broth (PDB) medium (4 days at 28°C) at different concentrations of AgNPs (60, 80, 100, 120, 140, 160, 180 and 200 μg/ml) was measured. Results: The results demonstrated that a minimum inhibition concentration (MIC) equal to 180 μg/ml was determined for AgNPs against A. parasiticus. The AgNPs effectively inhibited AFB1 production at a concentration of 90 μg/ml. Conclusion: The results obtained in this study show AgNPs at concentrations lower than the MIC drastically inhibited production of AFB1 by A. parasiticus in culture medium. The AgNPs may be useful to control AF contamination of susceptible crops in the field. PMID:26538778

  13. Simultaneous determination of aflatoxins and ochratoxin A in baby foods and paprika by HPLC with fluorescence detection: a single-laboratory validation study.

    PubMed

    Brera, C; Debegnach, F; De Santis, B; Pannunzi, E; Berdini, C; Prantera, E; Gregori, E; Miraglia, M

    2011-02-15

    Mycotoxins are toxic secondary metabolites of fungal origin, the major mycotoxins of food concern are aflatoxins and ochratoxin A. Due to the wide range of matrices susceptible to mycotoxin contamination, the possible co-occurrence, and the very wide range of concentration, validated versatile multi-mycotoxin and multi-matrix methods are strongly requested. A reversed phase HPLC method for the simultaneous determination of aflatoxins and ochratoxin A in baby foods and paprika was set up. Three bulk samples were prepared according to commercial availability, one for paprika and for baby foods, two different bulks were set, a corn based and a multi-cereal based baby food. A single-laboratory validation was performed, for each investigated level ten analyses were performed, relative standard deviations of repeatability (RSD(r)) and recovery factors were calculated; RSD(r) values ranged from 2% to 10% for AFB(1) and from 3% to 10% for OTA, while the recovery factors ranged from 86% to 96% for AFB(1) and from 77% to 96% for OTA. The checked compliance of the RSD(r) and recovery with the values reported in the current EU Regulations confirmed the fitting for purpose of the method. Limit of detection and LoQ values of the method were respectively 0.002 and 0.020 μg/kg for AFB(1) and 0.012 and 0.080 μg/kg for OTA in baby foods; and 0.002 and 0.200 μg/kg for AFB(1) and 0.012 and 0.660 μg/kg for OTA in paprika. The current method represents a good example of the possibility of a multi-mycotoxin and/or a multi-matrix analysis depending on the laboratory research or official control purposes.

  14. High sensitive immunoassay for multiplex mycotoxin detection with photonic crystal microsphere suspension array.

    PubMed

    Deng, Guozhe; Xu, Kun; Sun, Yue; Chen, Yu; Zheng, Tiesong; Li, Jianlin

    2013-03-05

    A novel, sensitive, and high throughput competitive immunoassay for multiplex mycotoxins was established by immobilizing the artificial antigens (Ags) of mycotoxins on the surfaces of three kinds of silica photonic crystal microsphere (SPCM) suspension arrays. The SPCMs were encoded by their reflectance peak positions. Aflatoxin B1 (AFB1), fumonisin B1 (FB1), and citrinin (CIT) spiked in the cereals were extracted, and the fluorescein isothiocyanate (FITC) labeled antibodies (Abs) of these mycotoxins were added into the centrifuge tube which contained the SPCMs of the modified artificial antigens (Ags). The fluorescence signal was collected by an array fluorescent scanner. The limit of detection (LOD) was as low as 0.5, 1, and 0.8 pg/mL for AFB1, FB1, and CIT, respectively. The new method provided a wide linear detection range from 0.001 to 10, 0.001 to 10, and 0.001 to 1 ng/mL for AFB1, FB1, and CIT, respectively. The mean recovery rates are in range of 74.7 ± 4.0% to 127.9 ± 4.4% for the three mycotoxins in corn, peanuts, and wheat. The developed method for mycotoxins was used to assay the AFB1, FB1, and CIT level in 10 naturally contaminated cereal samples, and the results of detection were in agreement with that of a classic enzyme-linked immunosorbent assay (ELISA) method. This method saves a large amount of reagents (10 μL volume) and detection time (<3 h) for multiplex mycotoxin assay.

  15. Mutagenic, antimutagenic, cytotoxic, and apoptotic activities of extracts from Pituranthos tortuosus.

    PubMed

    Abdelwahed, Afef; Skandrani, Ines; Kilani, Soumaya; Neffati, A; Sghaier, Mohamed Ben; Bouhlel, Ines; Boubaker, Jihed; Ammar, Rebaï Ben; Mahmoud, Amor; Ghedira, Kamel; Chekir-Ghedira, Leila

    2008-01-01

    Mutagenic and antimutagenic activities against direct acting mutagens, nifuroxazide (NF) and sodium azide (SA), and indirect acting mutagen aflatoxin B1 (AFB1) of extracts prepared from aerial parts of Pituranthos tortuosus were investigated in bacterial assay systems (i.e., the Ames test with Salmonella typhimurium TA100, TA98, TA1538, TA1535, and the SOS chromotest with Escherichia coli PQ 37). It was found that all extracts obtained from P. tortuosus decreased the mutagenicity induced by AFB1 (10 microg/assay), SA (1.5 microg/assay), and NF (20 microg/assay). Ethyl acetate, acetone, methanol, and total oligomer flavenoid extracts exhibited the highest inhibition level of mutagenicity induced by the indirect mutagen AFB1. In addition, antiproliferative and apoptotic properties of these extracts have also been reported using two leukemia cell lines, L1210 and K562. The results revealed that all extracts showed a significant cytotoxic effect on these cell lines, and the effect was greater in the presence of human K562 chronic myelogenous leukemia cells, whereas they do not induce apoptosis.

  16. Quantitative tritium exchange of (/sup 3/H) aflatoxin B1 during penetration through isolated human skin

    SciTech Connect

    Riley, R.T.; Kemppainen, B.W.; Norred, W.P.

    1988-05-31

    Tritium labelled aflatoxin B1 ((G-/sup 3/H)AFB1) underwent an almost total tritium exchange with water during penetration through isolated human skin. The process was not enzymatic and the site of exchange appeared to be within the epidermis. The mechanism which mediated this extensive exchange was not determined. However, the tritium in (G-/sup 3/H)AFB1 was found to be very susceptible to chemical conditions which favored carbanion formation at the alpha-carbon of the cyclopentenone ring. The relative effectiveness of the various solvents in mediating the loss of the tritium label was 1 N/sub 3/NaOH much greater than methanol greater than 1 N HCl greater than water. This work serves as a warning that (G-/sup 3/H)AFB1 can easily undergo significant changes in specific activity in biological tissues and under relatively mild experimental conditions. It is possible that conditions within the skin favor carbanion formation.

  17. The presence of aflatoxins and ochratoxin A in rice and rice products; and evaluation of dietary intake.

    PubMed

    Iqbal, Shahzad Zafar; Asi, Muhammad Rafique; Hanif, Usman; Zuber, Muhammad; Jinap, S

    2016-11-01

    In present study aflatoxins (AFs) and ochratoxin A (OTA) were analysed in 208 samples of rice and products collected from central areas of Punjab, Pakistan. The analysis was carried out using HPLC equipped with fluorescence detector. The results have shown that 35% of the samples were found contaminated with AFs, out of which 19% and 24% samples were found to be above the European Union (EU) maximum content for AFB1 and total AFs, respectively. About 19% samples were found contaminated with OTA and 14% samples were found to be above the EU maximum content. The highest mean level of AFB1 and total AFs were found in brown rice samples i.e. 8.91 and 12.4μg/kg, respectively. However, white rice samples have shown the highest mean level of OTA (8.50μg/kg) with highest level of 24.9μg/kg. The high mean dietary exposure 22.2 and 24.2ngkg(-1)bwday(-1) to AFB1 and OTA, respectively poses significant health hazard for local population.

  18. Impact of maximum levels in European legislation on exposure of mycotoxins in dried products: case of aflatoxin B1 and ochratoxin A in nuts and dried fruits.

    PubMed

    Van de Perre, Evelien; Jacxsens, Liesbeth; Lachat, Carl; El Tahan, Fouad; De Meulenaer, Bruno

    2015-01-01

    In this study the impact of setting European criteria on exposure to aflatoxin B1 via nuts and figs and ochratoxin A via dried fruits is evaluated for the Belgian population, as an example of the European population. Two different scenarios were evaluated. In scenario 1 all collected literature data are considered, assuming that there is no border control nor legal limits in Europe. In the second scenario, contamination levels above the maximum limits are excluded. The results from scenario 1 demonstrated that if no regulation is in place, AFB1 and OTA concentrations reported in the analysed food can have potential health risk to the population. The estimated exposure of OTA for scenario 2 is below the TDI of 5 ng/kg BW⋅day, indicating that OTA concentrations accepted by EU legislation pose a low risk to the Belgian population. For AFB1, the MOE values of scenario 2 are above 10,000 and can be considered to be of low health concern, based on BDML10 for humans, except for figs (MOE = 5782). This means that for all matrices, with exception of figs, the maximum values of AFB1 in the European legislation are sufficient to be of a low health concern for consumers.

  19. Fisetin Modulates Antioxidant Enzymes and Inflammatory Factors to Inhibit Aflatoxin-B1 Induced Hepatocellular Carcinoma in Rats.

    PubMed

    Maurya, Brajesh Kumar; Trigun, Surendra Kumar

    2016-01-01

    Fisetin, a known antioxidant, has been found to be cytotoxic against certain cell lines. However, the mechanism by which it inhibits tumor growth in vivo remains unexplored. Recently, we have demonstrated that Aflatoxin-B1 (AFB1) induced hepatocarcinogenesis is associated with activation of oxidative stress-inflammatory pathway in rat liver. The present paper describes the effect of in vivo treatment with 20 mg/kg b.w. Fisetin on antioxidant enzymes vis-a-vis oxidative stress level and on the profile of certain proinflammatory cytokines in the hepatocellular carcinoma (HCC) induced by two doses of 1 mg/kg b.w. AFB1 i.p. in rats. The reduced levels of most of the antioxidant enzymes, coinciding with the enhanced level of reactive oxygen species in the HCC liver, were observed to regain their normal profiles due to Fisetin treatment. Also, Fisetin treatment could normalize the enhanced expression of TNFα and IL1α, the two proinflammatory cytokines, reported to be involved in HCC pathogenesis. These observations were consistent with the regression of neoplastic lesion and declined GST-pi (placental type glutathione-S-transferase) level, a HCC marker, in the liver of the Fisetin treated HCC rats. The findings suggest that Fisetin attenuates oxidative stress-inflammatory pathway of AFB1 induced hepatocarcinogenesis.

  20. Phlomis mauritanica extracts reduce the xanthine oxidase activity, scavenge the superoxide anions, and inhibit the aflatoxin B1-, sodium azide-, and 4-nitrophenyldiamine-induced mutagenicity in bacteria.

    PubMed

    Limem, Ilef; Bouhlel, Ines; Bouchemi, Meriem; Kilani, Soumaya; Boubaker, Jihed; Ben-Sghaier, Mohamed; Skandrani, Ines; Behouri, Wissem; Neffati, Aicha; Ghedira, Kamel; Chekir-Ghedira, Leila

    2010-06-01

    Four extracts were prepared from the leaves of Phlomis mauritanica: lyophilized infusion, total oligomer flavonoids, methanol, and ethyl acetate extracts. The antimutagenic properties of these extracts were investigated by assessing the inhibition of the mutagenic effects of direct-acting mutagens such as sodium azide and 4-nitrophenylenediamine and indirect-acting mutagens like aflatoxin B1 (AFB1) using the Ames assay. The four extracts prepared from P. mauritanica strongly inhibit the mutagenicity induced by AFB1 in both Salmonella typhimurium TA 100 and TA 98 assay systems. Lyophilized infusion and methanol extracts at the dose of 250 microg per plate reduced AFB1 mutagenicity by 93% and 91%, respectively, in S. typhymurium strain TA 100. We examined also the antioxidant effect of these extracts by the enzymatic xanthine/xanthine oxidase assay. Result indicated that total oligomer flavonoids and ethyl acetate and methanol extracts were potent inhibitors of xanthine oxidase activity. In contrast, lyophilized infusion, total oligomer flavonoids, and methanol extracts exhibited a high degree of superoxide anion scavenging. Our findings emphasize the potential of P. mauritanica extracts to prevent mutations and oxidant effects. Furthermore, the results presented here could be an additional argument to support the use of this species as a medicinal and dietary plant.

  1. Individual and combined effects of Aflatoxin B1, Deoxynivalenol and Zearalenone on HepG2 and RAW 264.7 cell lines.

    PubMed

    Zhou, Hongyuan; George, Saji; Hay, Crystal; Lee, Joel; Qian, He; Sun, Xiulan

    2017-02-20

    To understand the combinatorial toxicity of mycotoxins, we measured the effects of individual, binary and tertiary combinations of Aflatoxin B1 (AFB1), Deoxynivalenol (DON) and Zearalenone (ZEN) on the cell viability and cellular perturbations of HepG2 and RAW 264.7 cells. The nature of mycotoxins interactions was assessed using mathematical modeling (Chou-Talalay). Mechanisms of cytotoxicity were studied using high content screening (HCS) that probed cytotoxicity responses, such as changes in intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), intracellular calcium ([Ca(2+)]i) flux, and cell membrane damage. Our results showed that individual cytotoxicity of mycotoxins in a decreasing order was DON>AFB1>ZEN. Varying combinations of mycotoxins at differing concentrations showed different types of interactions. Most of the mixtures showed increasing toxic effects-synergism and/or addition while antagonistic effects were observed with combination of AFB1+ZEN. Generally, combination of mycotoxins showed significantly increased intracellular ROS production and [Ca(2+)]i flux, and decreased MMP in both cell lines, showing that the synergistic and additive effects of mycotoxin combination originate from perturbations of multiple cellular functions. Additionally, this study demonstrated the applicability of HCS for gaining mechanistic understanding on the toxicity of individual as well as combinatorial mycotoxins, and also provided scientific bases for formulating regulatory policies.

  2. Antimutagenic activity of green tea polyphenols.

    PubMed

    Wang, Z Y; Cheng, S J; Zhou, Z C; Athar, M; Khan, W A; Bickers, D R; Mukhtar, H

    1989-07-01

    For centuries green tea has been a widely consumed beverage throughout the world. It is known to contain a number of pharmacologically active compounds. In this study water extracts of green tea (WEGT) and their major constituents, green tea polyphenols (GTP), were examined for antimutagenic activity. WEGT and GTP were found to significantly inhibit the reverse mutation induced by benzo[alpha]pyrene (BP), aflatoxin B1 (AFB1), 2-aminofluorene, and methanol extracts of coal tar pitch in Salmonella typhimurium TA100 and/or TA98 in the presence of a rat-liver microsomal activation system. GTP also inhibited gene forward mutation in V79 cells treated with AFB1 and BP, and also decreased the frequency of sister-chromatid exchanges and chromosomal aberrations in V79 cells treated with AFB1. The addition of GTP during and after nitrosation of methylurea resulted in a dose-dependent inhibition of mutagenicity. Studies to define the mechanism of the antimutagenic activity of GTP suggest that it may affect carcinogen metabolism, DNA adduct formation, the interaction of ultimate carcinogen or the scavenging of free radicals.

  3. Anti-genotoxic and free-radical scavenging activities of extracts from (Tunisian) Myrtus communis.

    PubMed

    Hayder, N; Abdelwahed, A; Kilani, S; Ammar, R Ben; Mahmoud, A; Ghedira, K; Chekir-Ghedira, L

    2004-11-14

    The effect of extracts from leaves of Myrtus communis on the SOS reponse induced by Aflatoxin B1 (AFB1) and Nifuroxazide was investigated in a bacterial assay system, i.e. the SOS chromotest with Escherichia coli PQ37. Aqueous extract, the total flavonoids oligomer fraction (TOF), hexane, chloroform, ethyl acetate and methanol extracts and essential oil obtained from M. communis significantly decreased the SOS response induced by AFB1 (10 microg/assay) and Nifuroxazide (20 microg/assay). Ethyl acetate and methanol extracts showed the strongest inhibition of the induction of the SOS response by the indirectly genotoxic AFB1. The methanol and aqueous extracts exhibited the highest level of protection towards the SOS-induced response by the directly genotoxic Nifuroxazide. In addition to anti-genotoxic activity, the aqueous extract, the TOF, and the ethyl acetate and methanol extracts showed an important free-radical scavenging activity towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. These results suggest the future utilization of these extracts as additives in chemoprevention studies.

  4. Multiplex lateral flow immunoassay for mycotoxin determination.

    PubMed

    Song, Suquan; Liu, Na; Zhao, Zhiyong; Njumbe Ediage, Emmanuel; Wu, Songling; Sun, Changpo; De Saeger, Sarah; Wu, Aibo

    2014-05-20

    A new lateral flow immunoassay (LFA) is proposed for qualitative and/or semiquantitative determination of aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON), and their analogues (AFs, ZEAs, DONs) in cereal samples. Each of the mycotoxin specific antibody was class specific and there was no cross reactivity to other groups of compounds. The visual limits of detection (vLOD) of the strip were 0.03, 1.6, and 10 μg/kg for AFB1, ZEA and DON, respectively. The calculated limits of detection (cLOD) were 0.05, 1, and 3 μg/kg, respectively. Meanwhile the cutoff values were achieved at 1, 50, and 60 μg/kg for AFB1, ZEA and DON, respectively. Recoveries ranged from 80% to 122% and RSD from 5% to 20%. Both the vLOD and cLOD for the three mycotoxins were lower than the EU maximum levels. Analysis of naturally contaminated maize samples resulted in a good agreement between the multiplex LFA and LC-MS/MS (100% for DONs and AFs, and 81% for ZEAs). Careful analysis of the results further explained the general overestimation of LFA compared to chromatographic methods for quantification of mycotoxins.

  5. Electrogenerated chemiluminescence of magnesium chlorophyllin a aqueous solution and its sensitive response to the carcinogen aflatoxin B1.

    PubMed

    Li, Xiuting; Yuan, Hongyan; Li, Lan; Xiao, Dan

    2014-05-15

    The chlorophylls, crucial participants of photosynthesis, are large conjugated molecules with special electron donor-acceptor properties. Based on this, many investigations on the electrogenerated chemiluminescence (ECL) of chlorophyll a (Chl a) were performed in organic solvents, but no efficient signals were detected. Herein, ECL research of magnesium chlorophyllins a (Chlorins a) from simple saponification of the natural Chl a was carried out, and highly efficient and stable ECL signal was obtained for the first time. The mechanism study indicated that the ECL resulted from radical ion annihilation. Under the optimal conditions, the effect of the key gas O2 on the ECL of Chlorins a aqueous solution was investigated, and the recoverable inhibition of O2 was obviously observed. What is more, owing to the strong non-covalent interaction between Chlorins a and the carcinogen aflatoxin B1 (AFB1), ECL intensity of Chlorins a aqueous solution exhibited fast, sensitive and selective response to AFB1 with a low detection limit of 0.027 ppb at the signal-to-noise ratio of 3. The costless and environmentally friendly ECL method opens a new potential way of the rapid detection of AFB1 in practical application.

  6. Graphene oxide and carboxylated graphene oxide: Viable two-dimensional nanolabels for lateral flow immunoassays.

    PubMed

    Yu, Li; Li, Peiwu; Ding, Xiaoxia; Zhang, Qi

    2017-04-01

    Graphene oxide (GO) and carboxylated GO were used as labels for lateral flow immunoassays, instead of the conventionally used colloidal gold and colored latex labels. A sensor is demonstrated that enables fast screening for aflatoxin B1 (AFB1) as a model analyte using the antibody-GO complex as the recognition element. The visual limit of detection and cut-off value for AFB1 are 0.3 and 1ng/mL, respectively. It is shown that GO and carboxylated GO are viable black labels for use in lateral flow assays, one typical advantage being the saving cost (compared to the use of colloidal gold). Qualitative results are achieved within 15min, and the analytical results were in good agreement with the reference LC MS/MS method. The method was successfully applied to the on-site determination of AFB1 in agricultural products. In our perception, it opens new possibilities for the screening of other toxins by lateral flow immunoassays using GO and carboxylated GO as labels.

  7. Lack of an Apparent Association between Mycotoxin Concentrations in Red Chili Peppers and Incidence of Gallbladder Cancer in India : an Ecological Study.

    PubMed

    Ikoma, Toshikazu; Kapoor, Vinay Kumar; Behari, Anu; Mishra, Kumudesh; Tsuchiya, Yasuo; Asai, Takao; Endoh, Kazuo; Okano, Kiyoshi; Nakamura, Kazutoshi

    2016-01-01

    Our recent studies conducted in South America have shown that mycotoxin contamination of red chili peppers (RCPs) may be associated with an increased risk of gallbladder cancer (GBC). Whether this relationship exists in India, a country with a high incidence of GBC and high consumption of RCPs, is unclear. We therefore measured concentrations of aflatoxins (AFs) and ochratoxin A (OTA) in RCPs from areas of low, medium, and high incidence of GBC in India, and compared these concentrations with GBC incidence in each area. Twentyone RCP samples were collected from nine cities (eight from a lowincidence area, five from a mediumincidence area, and eight from a highincidence area). Concentrations of AFs and OTA were measured using highperformance liquid chromatography. No significant differences in mean concentrations of AFs and OTA were found in the three areas. AFB1 levels in the lowincidence area (10.81 ?g/kg) and highincidence area (12.00 ?g/kg) were more than 2.2 and 2.4 times higher compared with the maximum permitted level of AFB1 in spices (5.0 ?g/kg) set by the Commission of the European Communities, or that (4.4 ?g/kg) obtained in our previous study in Chile. Our results show that the mean concentrations of mycotoxins in RCPs are similar among the three areas in India with different incidences of GBC. Further studies with human subjects are needed to evaluate any association between AFB1 and GBC.

  8. Identification of the Anti-Aflatoxinogenic Activity of Micromeria graeca and Elucidation of Its Molecular Mechanism in Aspergillus flavus

    PubMed Central

    El Khoury, Rhoda; Caceres, Isaura; Puel, Olivier; Bailly, Sylviane; Atoui, Ali; Oswald, Isabelle P.; El Khoury, André; Bailly, Jean-Denis

    2017-01-01

    Of all the food-contaminating mycotoxins, aflatoxins, and most notably aflatoxin B1 (AFB1), are found to be the most toxic and economically costly. Green farming is striving to replace fungicides and develop natural preventive strategies to minimize crop contamination by these toxic fungal metabolites. In this study, we demonstrated that an aqueous extract of the medicinal plant Micromeria graeca—known as hyssop—completely inhibits aflatoxin production by Aspergillus flavus without reducing fungal growth. The molecular inhibitory mechanism was explored by analyzing the expression of 61 genes, including 27 aflatoxin biosynthesis cluster genes and 34 secondary metabolism regulatory genes. This analysis revealed a three-fold down-regulation of aflR and aflS encoding the two internal cluster co-activators, resulting in a drastic repression of all aflatoxin biosynthesis genes. Hyssop also targeted fifteen regulatory genes, including veA and mtfA, two major global-regulating transcription factors. The effect of this extract is also linked to a transcriptomic variation of several genes required for the response to oxidative stress such as msnA, srrA, catA, cat2, sod1, mnsod, and stuA. In conclusion, hyssop inhibits AFB1 synthesis at the transcriptomic level. This aqueous extract is a promising natural-based solution to control AFB1 contamination. PMID:28257049

  9. RNA-Seq-based toxicogenomic assessment of fresh frozen and formalin-fixed tissues yields similar mechanistic insights.

    PubMed

    Auerbach, Scott S; Phadke, Dhiral P; Mav, Deepak; Holmgren, Stephanie; Gao, Yuan; Xie, Bin; Shin, Joo Heon; Shah, Ruchir R; Merrick, B Alex; Tice, Raymond R

    2015-07-01

    Formalin-fixed, paraffin-embedded (FFPE) pathology specimens represent a potentially vast resource for transcriptomic-based biomarker discovery. We present here a comparison of results from a whole transcriptome RNA-Seq analysis of RNA extracted from fresh frozen and FFPE livers. The samples were derived from rats exposed to aflatoxin B1 (AFB1 ) and a corresponding set of control animals. Principal components analysis indicated that samples were separated in the two groups representing presence or absence of chemical exposure, both in fresh frozen and FFPE sample types. Sixty-five percent of the differentially expressed transcripts (AFB1 vs. controls) in fresh frozen samples were also differentially expressed in FFPE samples (overlap significance: P < 0.0001). Genomic signature and gene set analysis of AFB1 differentially expressed transcript lists indicated highly similar results between fresh frozen and FFPE at the level of chemogenomic signatures (i.e., single chemical/dose/duration elicited transcriptomic signatures), mechanistic and pathology signatures, biological processes, canonical pathways and transcription factor networks. Overall, our results suggest that similar hypotheses about the biological mechanism of toxicity would be formulated from fresh frozen and FFPE samples. These results indicate that phenotypically anchored archival specimens represent a potentially informative resource for signature-based biomarker discovery and mechanistic characterization of toxicity.

  10. Mould incidence and mycotoxin contamination in maize kernels from Swat Valley, North West Frontier Province of Pakistan.

    PubMed

    Shah, Hamid Ullah; Simpson, Thomas J; Alam, Sahib; Khattak, Khanzadi Fatima; Perveen, Sajida

    2010-04-01

    Mould incidence and aflatoxin B1 (AFB1) and ochratoxin A (OTA) contamination as well as proximate composition and minerals content of maize kernels from Swat Valley, North West Frontier Province of Pakistan was studied during the year, 2007. Results indicated that the mean moisture content of the kernels was within the recommended safe storage levels of 15%. Across the whole valley, Aspergillus, Fusarium, Penicillium and Rhizopus were the most predominant fungal genera identified and amongst the mycotoxigenic species, Aspergillus flavus had the highest incidence. AFB1 content ranged from none to 30.92 microg/kg with the average values of 14.94 and 16.22 microg/kg for Upper and Lower Swat regions, respectively. Similar trend was observed for OTA with the contamination level ranged from <0.001 to 7.32 microg/kg. A significant numbers of samples contained AFB1 and OTA levels above the safe limits as recommended by the USFDA and EU but on the average the results were within the safe limit. These results indicate that maize consumers in Swat Valley may be exposed to the danger of aflatoxins and ochratoxins poisoning. Thus, there is a need for policy makers to establish and enforce maize quality standards and regulations related to moulds and mycotoxins across the area.

  11. A comparative study on the antimutagenic properties of aqueous extracts of Aspalathus linearis (rooibos), different Cyclopia spp. (honeybush) and Camellia sinensis teas.

    PubMed

    van der Merwe, J D; Joubert, E; Richards, E S; Manley, M; Snijman, P W; Marnewick, J L; Gelderblom, W C A

    2006-12-10

    Antimutagenic activity of aqueous extracts of the South African herbal teas, Aspalathus linearis (rooibos) and Cyclopia spp. (honeybush) was compared with that of Camellia sinensis (black, oolong and green) teas in the Salmonella mutagenicity assay using aflatoxin B(1) (AFB(1)) and 2-acetylaminofluorene (2-AAF) as mutagens. The present study presents the first investigation on antimutagenic properties of C. subternata, C. genistoides and C. sessiliflora. The herbal teas demonstrated protection against both mutagens in the presence of metabolic activation, with the exception of "unfermented" (green/unoxidised) C. genistoides against 2-AAF, which either protected or enhanced mutagenesis depending on the concentration. Antimutagenic activity of "fermented" (oxidised) rooibos was significantly (P<0.05) less than that of Camellia sinensis teas against AFB(1), while for 2-AAF it was less (P<0.05) than that of black tea and similar (P>0.05) to that of oolong and green teas. Antimutagenic activity of unfermented C. intermedia and C. subternata exhibited a similar protection as fermented rooibos against AFB(1). Against 2-AAF, fermented rooibos exhibited similar protective properties than unfermented C. intermedia and C. sessiliflora. Unfermented rooibos was less effective than the C. sinensis teas and fermented rooibos, but had similar (P>0.05) antimutagenicity to that of fermented C. sessiliflora against AFB(1) and fermented C. subternata against 2-AAF. Fermented C. intermedia and C. genistoides exhibited the lowest protective effect against 2-AAF, while fermented C. intermedia exhibited the lowest protection when utilising AFB(1) as mutagen. Aspalathin and mangiferin, major polyphenols in rooibos and Cyclopia spp., respectively, exhibited weak to moderate protective effects when compared to the major green tea catechin, (-)epigallocatechin gallate (EGCG). Antimutagenic activity of selected herbal tea phenolic compounds indicated that they contribute towards (i) observed

  12. Assessment of multi-mycotoxin adsorption efficacy of grape pomace.

    PubMed

    Avantaggiato, Giuseppina; Greco, Donato; Damascelli, Anna; Solfrizzo, Michele; Visconti, Angelo

    2014-01-15

    Grape pomace (pulp and skins) was investigated as a new biosorbent for removing mycotoxins from liquid media. In vitro adsorption experiments showed that the pomace obtained from Primitivo grapes is able to sequester rapidly and simultaneously different mycotoxins. Aflatoxin B1 (AFB1) was the most adsorbed mycotoxin followed by zearalenone (ZEA), ochratoxin A (OTA), and fumonisin B1 (FB1), whereas the adsorption of deoxynivalenol (DON) was negligible. AFB1 and ZEA adsorptions were not affected by changing pH values in the pH 3-8 range, whereas OTA and FB1 adsorptions were significantly affected by pH. Equilibrium adsorption isotherms obtained at different temperatures (5-70 °C) and pH values (3 and 7) were modeled and evaluated using the Freundlich, Langmuir, Sips, and Hill models. The goodness of the fits and the parameters involved in the adsorption mechanism were calculated by the nonlinear regression analysis method. The best-fitting models to describe AFB1, ZEA, and OTA adsorption by grape pomace were the Sips, Langmuir, and Freundlich models, respectively. The Langmuir and Sips models were the best models for FB1 adsorption at pH 7 and 3, respectively. The theoretical maximum adsorption capacities (mmol/kg dried pomace) calculated at pH 7 and 3 decreased in the following order: AFB1 (15.0 and 15.1) > ZEA (8.6 and 8.3) > OTA (6.3-6.9) > FB1 (2.2 and 0.4). Single- and multi-mycotoxin adsorption isotherms showed that toxin adsorption is not affected by the simultaneous presence of different mycotoxins in the liquid medium. The profiles of adsorption isotherms obtained at different temperatures and pH and the thermodynamic parameters (ΔG°, ΔH°, ΔS°) suggest that mycotoxin adsorption is an exothermic and spontaneous process, which involves physisorption weak associations. Hydrophobic interactions may be associated with AFB1 and ZEA adsorption, whereas polar noncovalent interactions may be associated with OTA and FB1 adsorption. In conclusion, this study

  13. The transfer of aflatoxin M1 in milk of ewes fed diet naturally contaminated by aflatoxins and effect of inclusion of dried yeast culture in the diet.

    PubMed

    Battacone, G; Nudda, A; Palomba, M; Mazzette, A; Pulina, G

    2009-10-01

    An experiment was carried out to investigate 1) the transfer of aflatoxin M1 (AFM1) into the milk of dairy ewes fed diets naturally contaminated with aflatoxin B1 (AFB1); 2) the effect of the addition of dried yeast culture in the diet on this transfer; and 3) the alteration of enzymatic activities in the liver of ewes fed diets contaminated with AFB1. Twenty-four Sarda dairy ewes were divided in 4 groups and fed a concentrate mix containing 4 amounts of wheat meal naturally contaminated with aflatoxins. The diet of the control group had no wheat meal, whereas that of treated groups had low, medium, or high amounts of contaminated wheat, which corresponded to 1.13, 2.30, and 5.03 microg of AFB1/kg of feed, respectively. The experiment lasted 14 d. On d 8 to 14 from the beginning of the trial, 12 g/d of a commercial dried yeast product (DYP) of Kluyveromyces lactis was added to the diet of each ewe. The AFM1 concentration in individual milk samples and the blood serum metabolites were measured periodically. The presence of AFM1 was first detected in milk on d 1 of administration, and then its concentration increased and approached a steady-state condition on d 3 simultaneously in all treated groups. The AFM1 in milk at the steady-state condition, which was linearly related to the AFB1 intake, was 39.72, 50.38, and 79.29 ng/L in the low-aflatoxin, medium-aflatoxin, and high-aflatoxin groups, respectively. The AFM1 concentration in milk of the high-aflatoxin group was approximately 1.5-fold greater than the European Commission maximum tolerance level (50 ng/kg). The addition of DYP to the diet did not affect the AFM1 concentration in milk. After the withdrawal of the contaminated concentrate mix, the AFM1 mean concentrations decreased quickly and were no longer detected after 3 d in all treated groups. Daily milk yield and composition did not differ because of aflatoxin treatment. Blood serum parameters (creatinine, glutamic oxalacetic transaminase, glutamic pyruvic

  14. MiR393 regulation of auxin signaling and redox-related components during acclimation to salinity in Arabidopsis.

    PubMed

    Iglesias, María José; Terrile, María Cecilia; Windels, David; Lombardo, María Cristina; Bartoli, Carlos Guillermo; Vazquez, Franck; Estelle, Mark; Casalongué, Claudia Anahí

    2014-01-01

    One of the most striking aspects of plant plasticity is the modulation of development in response to environmental changes. Plant growth and development largely depend on the phytohormone auxin that exerts its function through a partially redundant family of F-box receptors, the TIR1-AFBs. We have previously reported that the Arabidopsis double mutant tir1 afb2 is more tolerant to salt stress than wild-type plants and we hypothesized that down-regulation of auxin signaling might be part of Arabidopsis acclimation to salinity. In this work, we show that NaCl-mediated salt stress induces miR393 expression by enhancing the transcription of AtMIR393A and leads to a concomitant reduction in the levels of the TIR1 and AFB2 receptors. Consequently, NaCl triggers stabilization of Aux/IAA repressors leading to down-regulation of auxin signaling. Further, we report that miR393 is likely involved in repression of lateral root (LR) initiation, emergence and elongation during salinity, since the mir393ab mutant shows reduced inhibition of emergent and mature LR number and length upon NaCl-treatment. Additionally, mir393ab mutant plants have increased levels of reactive oxygen species (ROS) in LRs, and reduced ascorbate peroxidase (APX) enzymatic activity compared with wild-type plants during salinity. Thus, miR393 regulation of the TIR1 and AFB2 receptors could be a critical checkpoint between auxin signaling and specfic redox-associated components in order to coordinate tissue and time-specific growth responses and tolerance during acclimation to salinity in Arabidopsis.

  15. Distinctive expression patterns and roles of the miRNA393/TIR1 homolog module in regulating flag leaf inclination and primary and crown root growth in rice (Oryza sativa).

    PubMed

    Bian, Hongwu; Xie, Yakun; Guo, Fu; Han, Ning; Ma, Shengyun; Zeng, Zhanghui; Wang, Junhui; Yang, Yinong; Zhu, Muyuan

    2012-10-01

    • MicroRNA (miRNA)-mediated regulation of auxin signaling components plays a critical role in plant development. miRNA expression and functional diversity contribute to the complexity of regulatory networks of miRNA/target modules. • This study functionally characterizes two members of the rice (Oryza sativa) miR393 family and their target genes, OsTIR1 and OsAFB2 (AUXIN SIGNALING F-BOX), the two closest homologs of Arabidopsis TRANSPORT INHIBITOR RESPONSE 1 (TIR1). • We found that the miR393 family members possess distinctive expression patterns, with miR393a expressed mainly in the crown and lateral root primordia, as well as the coleoptile tip, and miR393b expressed in the shoot apical meristem. Transgenic plants overexpressing miR393a/b displayed a severe phenotype with hallmarks of altered auxin signaling, mainly including enlarged flag leaf inclination and altered primary and crown root growth. Furthermore, OsAFB2- and OsTIR1-suppressed lines exhibited increased inclination of flag leaves at the booting stage, resembling miR393-overexpressing plants. Moreover, yeast two-hybrid and bimolecular fluorescence complementation assays showed that OsTIR1 and OsAFB2 interact with OsIAA1. • Expression diversification of miRNA393 implies the potential role of miRNA regulation during species evolution. The conserved mechanisms of the miR393/target module indicate the fundamental importance of the miR393-mediated regulation of auxin signal transduction in rice.

  16. MiR393 Regulation of Auxin Signaling and Redox-Related Components during Acclimation to Salinity in Arabidopsis

    PubMed Central

    Iglesias, María José; Lombardo, María Cristina; Bartoli, Carlos Guillermo; Vazquez, Franck; Estelle, Mark; Casalongué, Claudia Anahí

    2014-01-01

    One of the most striking aspects of plant plasticity is the modulation of development in response to environmental changes. Plant growth and development largely depend on the phytohormone auxin that exerts its function through a partially redundant family of F-box receptors, the TIR1-AFBs. We have previously reported that the Arabidopsis double mutant tir1 afb2 is more tolerant to salt stress than wild-type plants and we hypothesized that down-regulation of auxin signaling might be part of Arabidopsis acclimation to salinity. In this work, we show that NaCl-mediated salt stress induces miR393 expression by enhancing the transcription of AtMIR393A and leads to a concomitant reduction in the levels of the TIR1 and AFB2 receptors. Consequently, NaCl triggers stabilization of Aux/IAA repressors leading to down-regulation of auxin signaling. Further, we report that miR393 is likely involved in repression of lateral root (LR) initiation, emergence and elongation during salinity, since the mir393ab mutant shows reduced inhibition of emergent and mature LR number and length upon NaCl-treatment. Additionally, mir393ab mutant plants have increased levels of reactive oxygen species (ROS) in LRs, and reduced ascorbate peroxidase (APX) enzymatic activity compared with wild-type plants during salinity. Thus, miR393 regulation of the TIR1 and AFB2 receptors could be a critical checkpoint between auxin signaling and specfic redox-associated components in order to coordinate tissue and time-specific growth responses and tolerance during acclimation to salinity in Arabidopsis. PMID:25222737

  17. The Master Transcription Factor mtfA Governs Aflatoxin Production, Morphological Development and Pathogenicity in the Fungus Aspergillus flavus

    PubMed Central

    Zhuang, Zhenhong; Lohmar, Jessica M.; Satterlee, Timothy; Cary, Jeffrey W.; Calvo, Ana M.

    2016-01-01

    Aspergillus flavus produces a variety of toxic secondary metabolites; among them, the aflatoxins (AFs) are the most well known. These compounds are highly mutagenic and carcinogenic, particularly AFB1. A. flavus is capable of colonizing a number of economically-important crops, such as corn, cotton, peanut and tree nuts, and contaminating them with AFs. Molecular genetic studies in A. flavus could identify novel gene targets for use in strategies to reduce AF contamination and its adverse impact on food and feed supplies worldwide. In the current study, we investigated the role of the master transcription factor gene mtfA in A. flavus. Our results revealed that forced overexpression of mtfA results in a drastic decrease or elimination of several secondary metabolites, among them AFB1. The reduction in AFB1 was accompanied by a decrease in aflR expression. Furthermore, mtfA also regulates development; conidiation was influenced differently by this gene depending on the type of colonized substrate. In addition to its effect on conidiation, mtfA is necessary for the normal maturation of sclerotia. Importantly, mtfA positively affects the pathogenicity of A. flavus when colonizing peanut seeds. AF production in colonized seeds was decreased in the deletion mtfA strain and particularly in the overexpression strain, where only trace amounts were detected. Interestingly, a more rapid colonization of the seed tissue occurred when mtfA was overexpressed, coinciding with an increase in lipase activity and faster maceration of the oily part of the seed. PMID:26805883

  18. [Molecular genetic and epigenetic mechanisms of hepatocarcinogenesis].

    PubMed

    Xue, Kai-Xian

    2005-06-01

    Hepatocellular carcinoma (HCC) is a major type of primary liver cancer and one of the most frequent human malignant neoplasms. Common risk factors of human HCC include chronic hepatitis virus (HBV and HCV) infection, dietary aflatoxin B1 (AFB1) ingestion, chronic alcohol abuse, and cirrhosis associated with genetic liver diseases. Hepatocarcinogenesis is the result of interaction between hereditary and environmental factors. Inheritance determines individual susceptibility to cancer; environment determines which susceptible individuals express cancer. Studies of genetic and epigenetic mechanisms of hepatocarcinogenesis showed that HCC development is a complex polygene and multipathway process; the activation of proto-oncogenes and the inactivation of tumor suppressor genes induced by genetic and epigenetic alterations are core biological processes of hepatocarcinogenesis; RB1, p53, and Wnt pathways are commonly affected in HCCs of different etiologies, which may reflect common pathologic sequence of HCC: chronic liver injury, cirrhosis, atypical hyperplastic nodules, and HCC of early stages. Hepatitis virus infection-associated HCCs have frequent alterations in RB1 pathway, including methylation of p16INK4a and RB1 genes and amplification of Cyclin D1. AFB1 exposure-associated HCCs have frequent alterations in p53 pathway; the G-->T mutation of p53 gene at codon 249 has been identified as a genetic hallmark of HCC caused by AFB1. Alcoholism-associated HCCs have frequent alterations in both RB1 and p53 pathways. The roles of some important genes related to cell apoptosis, DNA repair, drug metabolism, and tumor metastasis in hepatocarcinogenesis had been discussed.

  19. The Hotspot for (Global) One Health in Primary Food Production: Aflatoxin M1 in Dairy Products.

    PubMed

    Frazzoli, Chiara; Gherardi, Paola; Saxena, Navneet; Belluzzi, Giancarlo; Mantovani, Alberto

    2016-01-01

    One Health involves the multifaceted environment-animal-human web: nevertheless, the role of toxicological issues has yet to be fully explored in this context. Aflatoxin B1 (AFB1) contamination of feeds is a risk for the health of several farm animals, including fishes; milk is the only food of animal origin where a significant feed-food carry over may occur. The main AFB1-related compound present in milk is the hydroxy-metabolite aflatoxin M1 (AFM1). Besides contamination of raw milk, AFM1 is of concern for the whole dairy chain; AFM1 may also contaminate the milk of several other ruminants used for milk/dairy production. In a One Health perspective, milk represents a sentinel matrix for AFB1 vulnerability of the agro-food system, that is crucial in a phase when food/nutritional security becomes a global issue and climatic changes may affect agricultural productions. In the global setting, food chain exposure to long-term toxicants, such as AFM1, is a growing concern for economically developing countries, whereas global trade and climatic change makes AFM1 an emerging hot issue in economically developed countries as well. We critically review the state of the art on AFM1 risk assessment and risk management using two scenarios as case studies: a European Union country where the health system aims at ensuring a high-level protection of food chain (Italy) and the world's largest (and economically developing) producer of dairy products by volume (India). The case studies are used to provide building blocks for a global One Health framework.

  20. The Hotspot for (Global) One Health in Primary Food Production: Aflatoxin M1 in Dairy Products

    PubMed Central

    Frazzoli, Chiara; Gherardi, Paola; Saxena, Navneet; Belluzzi, Giancarlo; Mantovani, Alberto

    2017-01-01

    One Health involves the multifaceted environment-animal-human web: nevertheless, the role of toxicological issues has yet to be fully explored in this context. Aflatoxin B1 (AFB1) contamination of feeds is a risk for the health of several farm animals, including fishes; milk is the only food of animal origin where a significant feed-food carry over may occur. The main AFB1-related compound present in milk is the hydroxy-metabolite aflatoxin M1 (AFM1). Besides contamination of raw milk, AFM1 is of concern for the whole dairy chain; AFM1 may also contaminate the milk of several other ruminants used for milk/dairy production. In a One Health perspective, milk represents a sentinel matrix for AFB1 vulnerability of the agro-food system, that is crucial in a phase when food/nutritional security becomes a global issue and climatic changes may affect agricultural productions. In the global setting, food chain exposure to long-term toxicants, such as AFM1, is a growing concern for economically developing countries, whereas global trade and climatic change makes AFM1 an emerging hot issue in economically developed countries as well. We critically review the state of the art on AFM1 risk assessment and risk management using two scenarios as case studies: a European Union country where the health system aims at ensuring a high-level protection of food chain (Italy) and the world’s largest (and economically developing) producer of dairy products by volume (India). The case studies are used to provide building blocks for a global One Health framework. PMID:28210616

  1. Chemoprevention of aflatoxin B1-initiated and carbon tetrachloride-promoted hepatocarcinogenesis in the rat by green tea.

    PubMed

    Qin, G; Ning, Y; Lotlikar, P D

    2000-01-01

    Chemoprevention of hepatocarcinogenesis by green tea (GT) has been examined in young male Fischer rats fed AIN-76A diet with aflatoxin B1 (AFB1) and CCl4 as the initiator and promoter, respectively. Animals were administered AFB1 (0.25 mg/kg body wt ip) twice a week for 2 weeks, and 2 weeks later, CCl4 was injected (0.8 ml/kg body wt ip) once per week for 11 weeks. Rats given 0.5% GT in their drinking water before and during initiation (0-4 wk) or during promotion (6-16 wk) or throughout the experimental period were sacrificed 24 hours after the last dose of CCl4. Bromodeoxyuridine incorporation as a measure of cell proliferation and glutathione S-transferase placentalform- and gamma-glutamyl transpeptidase-positive hepatic foci were analyzed by histochemical methods. Feeding of GT during initiation or promotion inhibited the number of glutathione S-transferase placental form- and gamma-glutamyl transpeptidase-positive hepatic foci by 30-40% and the area and volume by 50%. GT treatment throughout the period inhibited the number of both types of hepatic foci by 60% and the area and volume by 75-80%. Cell proliferation was inhibited 35% by GT given during promotion, whereas inhibition was 65% when GT was given during initiation or throughout the period. These results indicate that GT feeding inhibits initiation and promotion steps of AFB1 hepatocarcinogenesis and that the inhibition of cell proliferation is responsible for the inhibition of promotion.

  2. Antifungal activity of essential oil of Ziziphora clinopodioides and the inhibition of aflatoxin B1 production in maize grain.

    PubMed

    Moghadam, Hediyeh Davoudi; Sani, Ali Mohamadi; Sangatash, Masoomeh Mehraban

    2016-03-01

    The aim of this study was to determine the antifungal effect of the essential oil obtained from Ziziphora clinopodioides L on two fungi species including Aspergillus flavus and Aspergillus parasiticus using microdilution method. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were determined for the essential oil at 10 different concentrations (i.e. 25,000, 12,500, 6250, 3125, 1562.5, 781.25, 390.625, 195.31, 97.65, and 48.82 µg/ml). Finally, the effect of the essential oil at six levels (6250, 3125, 1600, 800, 400, and 196 µg/ml) was investigated on the growth and activity of A. flavus and A. parasiticus, and also toxin production of these species in maize at 0.97 aw and 25°C after 29 days. Aflatoxin B1 (AFB1) content was assayed by enzyme linked immuno-sorbent assay technique. Results showed that essential oil of Z. clinopodioides was found more effective on A. parasiticus than A. flavus in both in vitro and in vivo conditions. Z. clinopodioides oil exhibited the same MIC value in the liquid medium against all fungal strains (48.82 µg/ml), while it showed different activity against A. flavus and A. parasiticus with MFC values of 781.25 and 390.625 µg/ml respectively. Under storage condition in maize, AFB1 production was significantly (p < 0.05) repressed at the concentration of 6250 µg/ml for A. flavus and 6250 and 3125 µg/ml for A. parasiticus. At the lower concentrations, the AFB1 production increased gradually. The results of the present study indicated that the essential oil of Z. clinopodioides had significant antifungal activity (p < 0.05); therefore, it can be used as an antifungal agent in the food and medicinal industries.

  3. Exposure to organochlorine pesticides is an independent risk factor of hepatocellular carcinoma: a case-control study.

    PubMed

    Zhao, Benhua; Shen, Heqing; Liu, Feng; Liu, Sheng; Niu, Jianjun; Guo, Fei; Sun, Xueli

    2012-11-01

    Primary hepatocellular carcinoma (HCC) is highly prevalent in China. Although hepatitis B virus (HBV) and aflatoxin B1 (AFB1) are considered the major risk factors, among the high-risk cohorts only a small fraction develops liver cancer. Therefore, we investigated whether organochlorine pesticide exposure contributed to HCC risk in the Xiamen population. The questionnaire database was built from 346 HCC cases and 961 healthy controls during 2007-2009. The serum levels of α-, β-, γ-, δ-HCH, 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane (p,p'-DDT), (1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p'-DDE), 1,1,1-trichloro-2,2-bis (o-chlorophenyl) ethane and 1,1-dichloro-2,2-bis (p-chlorophenyl) ethane were measured by gas chromatography-tandem mass spectrometer, and statistical analysis was done using SPSS16. Significantly, we observed p,p'-DDT and p,p'-DDE, and at the first time β-HCH displayed quartile dose-dependent HCC risk trends; p,p'-DDT showed positive (i.e., synergistic) interactions with HBV, diabetes mellitus, AFB1 and polyaromatic hydrocarbon (PAH) exposure, but negative (i.e., antagonistic) interaction with heavy drinking; p,p'-DDE had positive interaction with PAH but negative interaction with HBV and p,p'-DDT; and β-HCH positively interacted with p,p'-DDT but negatively interacted with heavy drinking and diabetes. p,p'-DDT, p,p'-DDE and β-HCH were independent HCC risk factors. Because of their synergistic interactions with other factors, the high-level exposure combined with common AFB1 and HBV exposure in the investigated area may greatly enhance the risk of HCC.

  4. Does aflatoxin exposure in the United Kingdom constitute a cancer risk?

    PubMed Central

    Harrison, J C; Carvajal, M; Garner, R C

    1993-01-01

    Although the aflatoxins were discovered more than 30 years ago, there is still considerable controversy surrounding their human health effects. Most countries have introduced legislation to control the level of aflatoxins in food, but it is not known if these permitted levels still pose a significant cancer risk. Furthermore, it is unlikely that all the sources of human aflatoxin exposure have been discovered, nor if the liver is the only, or indeed, major target organ for aflatoxin-induced cancer in man. In our laboratory we have used both immunological and HPLC methods to examine human DNA from a variety of tissues and organs to identify and quantify aflatoxin DNA-adducts. We have already detected aflatoxin B1 (AFB1)-DNA adducts in formalin-fixed tissue from an acute poisoning incident in Southeast Asia. Here we have examined human colon and rectum DNA from normal and tumorous tissue obtained from cancer patients and colon, liver, pancreas, breast, and cervix DNA from autopsy specimens. AFB1-DNA adducts were detected in all tissue types examined and ranged from 0-60 adducts/10(6) nucleotides. Where sample size allowed, the adduct levels were confirmed by HPLC analysis. Tumor tissues tended to have higher adduct levels than normal tissue from the same individual, and levels generally increased with patient age. In samples analyzed by HPLC, the adducts present had the chromatographic properties of [8,9-dihydro-8-(N5-formyl)-2',5',6'-triamino-4'-oxo-(N5-pyramidyl) -9- hydroxy-aflatoxin B1, the ring-opened form of the AFB1-guanine adduct.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8319666

  5. Analysis of fumonisin B1 removal by microorganisms in co-occurrence with aflatoxin B1 and the nature of the binding process.

    PubMed

    Pizzolitto, Romina P; Salvano, Mario A; Dalcero, Ana M

    2012-06-01

    The objectives of this investigation were to evaluate the ability of Saccharomyces cerevisiae CECT 1891 and Lactobacillus acidophilus 24 to remove fumonisin B(1) (FB(1)) from liquid medium; to determine the nature of the mechanism involved in FB(1)-microorganism interaction and to analyze whether the presence of aflatoxin B(1) (AFB(1)) interferes with the removal of FB(1) and vice versa. The results obtained indicated that: (i) both microorganisms were able to remove FB(1) from liquid medium; (ii) the removal was a fast and reversible process; (iii) cell viability was not necessary; (iv) the amount of FB(1) removed was both toxin- and microorganism concentration-dependent; (v) the process did not involve chemical modification of FB(1) molecules; and (vi) cell wall structural integrity of the microorganisms was required for FB(1) removal. Consequently, we propose that the mechanism involved in the removal of FB(1) is a physical adsorption (physisorption) of the toxin molecule to cell wall components of the microorganisms. It is highly probable that FB(1) and AFB(1) co-occur in contaminated foods, since the fungal genera Aspergillus and Fusarium frequently occur simultaneously. Therefore, we analyzed whether the presence of AFB(1) interferes with the removal of FB(1) by the microorganisms previously evaluated, and vice versa. Studies of co-occurrence of both mycotoxins clearly showed that they did not compete for binding sites on the microorganism cell wall and the presence of one toxin did not modify the efficiency of the organism in the removal of the other mycotoxin. These findings may be useful for optimization of mycotoxin binding and provide an important contribution to research on microorganisms with ability to remove these secondary metabolites.

  6. Mould and mycotoxin exposure assessment of melon and bush mango seeds, two common soup thickeners consumed in Nigeria.

    PubMed

    Ezekiel, Chibundu N; Sulyok, Michael; Somorin, Yinka; Odutayo, Foluke I; Nwabekee, Stella U; Balogun, Afeez T; Krska, Rudolf

    2016-11-21

    An examination of the mould and fungal metabolite pattern in melon and bush mango seeds locally produced in Nigeria was undertaken in order to understand the mycotoxicological risk posed to consumers of both of these important and commonly consumed soup thickeners. The variation in mycotoxin levels in graded categories of both foodstuffs were also determined. Aspergillus, Fusarium, Penicillium, Mucorales and Trichoderma were the recovered fungi from the foodstuffs with Aspergillus species dominating (melon=97.8%; bush mango=89.9%). Among the Aspergillus species identified Aspergillus section Flavi dominated (melon: 72%; bush mango: 57%) and A. flavus, A. parasiticus, A. parvisclerotigenus and A. tamarii were the recovered species. About 56% and 73% of the A. flavus isolates from melon and bush mango seed samples, respectively were aflatoxigenic. Thirty-four and 59 metabolites including notable mycotoxins were found in the melon and bush mango seeds respectively. Mean aflatoxin levels (μg/kg) in melon (aflatoxin B1 (AFB1)=37.5 and total aflatoxins=142) and bush mango seeds (AFB1=68.1 and total aflatoxins=61.7) were higher than other mycotoxins, suggesting potential higher exposure for consumer populations. Significantly (p<0.05) higher levels of mycotoxins were found in hand-peeled melon and discoloured bush mango seeds than in machine-peeled melon and non-discoloured seeds except for HT-2 and T-2 toxins which occurred conversely. All melon and bush mango seeds exceeded the 2μg/kg AFB1 limit whereas all melon and 55% of bush mango seeds exceeded the 4μg/kg total aflatoxin EU limit adopted in Nigeria. This is the first report of (1) mycotoxin co-occurrence in bush mango seeds, (2) cyclopiazonic acid, HT-2 toxin, moniliformin, mycophenolic acid, T-2 toxin and tenuazonic acid occurrence, and (3) mycotoxin exposure assessment of both foodstuffs.

  7. Variation in fungal microbiome (mycobiome) and aflatoxin in stored in-shell peanuts at four different areas of China

    PubMed Central

    Ding, Ning; Xing, Fuguo; Liu, Xiao; Selvaraj, Jonathan N.; Wang, Limin; Zhao, Yueju; Wang, Yan; Guo, Wei; Dai, Xiaofeng; Liu, Yang

    2015-01-01

    The contamination of peanuts with Aspergillus sp. and subsequently aflatoxins is considered to be one of the most serious safety problems in the world. Mycobiome in peanuts is critical for aflatoxin production and food safety. To evaluate the biodiversity and ecological characteristics of whole communities in stored peanuts, the barcoded Illumina paired-end sequencing of the internal transcribed spacer 2 (ITS2) region of rDNA was used to characterize the peanut mycobiome monthly over a period of 1 year at four main peanut grown areas, i.e., Liaoning (LN, North East), Shandong (SD, East), Hubei (HB, Central), and Guangdong (GD, South) provinces. The fungal diversity of peanuts stored in SD was the highest with 98 OTUs and 43 genera, followed by LN, HB and GD. In peanuts stored in SD, Rhizopus, Emericella, and Clonostachys were predominant. In peanuts from LN, Penicillium, Eurotium, and Clonostachys were abundant. In peanuts from HB, Penicillium, Eurotium, and Aspergillus were higher. In GD peanuts, Eurotium, Aspergillus, and Emericella were mainly seen. The abundances of Aspergillus in LN, SD, HB, and GD were 0.53, 6.29, 10.86, and 25.75%, respectively. From the North of China to the South, that increased over the latitude, suggesting that the higher temperature and relative humidity might increase the risk of peanuts contaminated with Aspergillus and aflatoxins. During the storage, Aspergillus levels were higher at 7–12 months than in 0–6 months, suggesting that the risk increases over storage time. At 7–10 months, AFB1 was higher in four areas, while declined further. The reduction of AFB1 might be attributed to the inhibition and degradation of AFB1 by Aspergillus niger or to the combination with the compounds of peanuts. This is the first study that identified the mycobiome and its variation in stored peanuts using ITS2 sequencing technology, and provides the basis for a detailed characterization of whole mycobiome in peanuts. PMID:26557107

  8. In vitro and in vivo characterization of mycotoxin-binding additives used for animal feeds in Mexico.

    PubMed

    Marroquín-Cardona, A; Deng, Y; Taylor, J F; Hallmark, C T; Johnson, N M; Phillips, T D

    2009-05-01

    The study was conducted to characterize and compare twelve different additives distributed in Mexico as mycotoxin binders utilizing: (1) equilibrium isothermal analysis for aflatoxin B(1) (AFB(1)) adsorption, (2) a variety of mineralogical probes, and (3) Hydra toxicity bioassay. The test additives Milbond-TX (MLB), Mycoad (MCA), Volclay FD181 (VOL), Fixat (FXT), Toxinor (TOX), Mexsil (MEX), Mycosil (MYC), Klinsil (KLS), Zeotek (ZEO), Duotek (DUO), Mycosorb (MSB), and Mycofix Plus 3.0 (MIX) were compared with NovaSil Plus (NSP). Isotherms for AFB(1) adsorption were conducted at pH 2 and pH 6.5, mimicking pH conditions in the stomach and small intestine. Mineralogical analysis included determination of swelling volume, X-ray diffraction analysis, and fractionation procedures. A Hydra vulgaris toxicity study was performed to evaluate the potential safety of the additives. Computer-generated isotherm data were fit using the Langmuir model, and parameters of Q(max) and K(d) were estimated. The most effective additives for AFB(1) at both pH conditions were NSP, MLB, MCA and VOL, while the least effective was MSB. The amounts of sand, silt and clay fractions varied among the additives. Nine of the additives showed the presence of smectite. Most of the additives were found to be non-toxic to Hydra except for the organoclays (ZEO, DUO) and MSB. In general, NSP demonstrated the highest sorption capacity in the bulk material and the different fractions. Studies to characterize these binding additives further and to evaluate their multiple mycotoxin sorption claims are ongoing.

  9. Common African cooking processes do not affect the aflatoxin binding efficacy of refined calcium montmorillonite clay

    PubMed Central

    Elmore, Sarah E.; Mitchell, Nicole; Mays, Travis; Brown, Kristal; Marroquin-Cardona, Alicia; Romoser, Amelia; Phillips, Timothy D.

    2013-01-01

    Aflatoxins are common contaminants of staple crops, such as corn and groundnuts, and a significant cause of concern for food safety and public health in developing countries. Aflatoxin B1 (AFB1) has been implicated in the etiology of acute and chronic disease in humans and animals, including growth stunting, liver cancer and death. Cost effective and culturally acceptable intervention strategies for the reduction of dietary AFB1 exposure are of critical need in populations at high risk for aflatoxicosis. Fermented gruels consisting of cornmeal are a common source for such exposure and are consumed by both children and adults in many countries with a history of frequent, high-level aflatoxin exposure. One proposed method to reduce aflatoxins in the diet is to include a selective enterosorbent, Uniform Particle Size NovaSil (UPSN), as a food additive in contaminated foods. For UPSN to be effective in this capacity, it must be stable in complex, acidic mixtures that are often exposed to heat during the process of fermented gruel preparation. Therefore, the objective of the present study was to test the ability of UPSN to sorb aflatoxin while common cooking conditions were applied. The influence of fermentation, heat treatment, acidity, and processing time were investigated with and without UPSN. Analyses were performed using the field-practical Vicam assay with HPLC verification of trends. Our findings demonstrated that UPSN significantly reduced aflatoxin levels (47-100%) in cornmeal, regardless of processing conditions. Upon comparison of each element tested, time appeared to be the primary factor influencing UPSN efficacy. The greatest decreases in AFB1 were reported in samples allowed to incubate (with or without fermentation) for 72 hrs. This data suggests that addition of UPSN to staple corn ingredients likely to contain aflatoxins would be a sustainable approach to reduce exposure. PMID:24311894

  10. Protective effect of Ocimum sanctum on 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene and aflatoxin B1 induced skin tumorigenesis in mice

    SciTech Connect

    Rastogi, Shipra; Shukla, Yogeshwer; Paul, Bhola N.; Chowdhuri, D. Kar; Khanna, Subhash K.; Das, Mukul

    2007-11-01

    A study on the protective effect of alcoholic extract of the leaves of Ocimum sanctum on 3-mthylcholanthrene (MCA), 7,12-dimethylbenzanthracene (DMBA) and aflatoxin B{sub 1} (AFB{sub 1}) induced skin tumorigenesis in a mouse model has been investigated. The study involved pretreatment of mice with the leaf extract prior to either MCA application or tetradecanoyl phorbol acetate (TPA) treatment in a two-stage tumor protocol viz a viz, DMBA/TPA and AFB1/TPA. The results of the present study indicate that the pretreatment with alcoholic extract of the leaves of O. sanctum decreased the number of tumors in MCA, DMBA/TPA and AFB1/TPA treated mice. The skin tumor induced animals pretreated with alcoholic extract led to a decrease in the expression of cutaneous {gamma}-glutamyl transpeptidase (GGT) and glutathione-S-transferase-P (GST-P) protein. The histopathological examination of skin tumors treated with leaf extract showed increased infiltration of polymorphonuclear, mononuclear and lymphocytic cells, decreased ornithine decarboxylase activity with concomitant enhancement of interleukin-1{beta} (IL-1{beta}) and tumor necrosis factor-{alpha} (TNF-{alpha}) in the serum, implying the in vivo antiproliferative and immunomodulatory activity of leaf extract. The decrease in cutaneous phase I enzymes and elevation of phase II enzymes in response to topical application of leaf extract prior to MCA, AFB1, DMBA/TPA and AFB1/TPA treatment indicate the possibility of impairment in reactive metabolite(s) formation and thereby reducing skin carcinogenicity. Furthermore, pretreatment of leaf extract in the carcinogen induced animals resulted in elevation of glutathione levels and decrease in lipid peroxidation along with heat shock protein expression, indicating a scavenging or antioxidant potential of the extract during chemical carcinogenesis. Thus it can be concluded that leaf extract of O. sanctum provides protection against chemical carcinogenesis in one or more of the

  11. Aflatoxins in black tea in Iran.

    PubMed

    Pouretedal, Zohreh; Mazaheri, Mansooreh

    2013-01-01

    Aflatoxins (AFs) are highly toxic, and carcinogenic secondary fungal metabolites and have been detected in various food commodities. In this regard, 40 black tea samples including domestic and imported black tea were analysed for aflatoxin contamination by high-performance liquid chromatography using a post-column derivatisation procedure (Kobra cell) with fluorescence detection. Samples were randomly collected in 2010 from Tehran markets. The results revealed that 30 among 40 samples were contaminated with aflatoxins (27.5% of the total). Mean AFB1 content was 10.0 ng/g and mean of aflatoxin total was 12.07 ng/g for the 11 contaminated samples.

  12. Occurrence of aflatoxin M1 in urines from rural and urban adult cohorts in Bangladesh.

    PubMed

    Ali, Nurshad; Hossain, Khaled; Blaszkewicz, Meinolf; Rahman, Mashiur; Mohanto, Nayan Chandra; Alim, Abdul; Degen, Gisela H

    2016-07-01

    Aflatoxins are important mycotoxins produced by Aspergillus flavus and A. parasiticus, moulds which contaminate mainly grains and nuts, especially in hot and humid climate. Presence of aflatoxin B1 (AFB1), the most toxic one and a potent hepatocarcinogen, has been reported in food and feed in Bangladesh and raised concerns about mycotoxin exposure in the population. Biomonitoring provides the best approach to assess human exposure from various sources and by all routes. Part of the ingested AFB1 is converted in the body to aflatoxin M1 (AFM1), a metabolite that has served as biomarker of AFB1 exposure, as it is excreted in urine, and thus enables non-invasive sampling, a relevant aspect in field studies. This investigation measured the AFM1 concentration in urines collected from adult residents of a rural (n = 52) and an urban (n = 43) area in the Rajshahi district of Bangladesh. The urinary levels of AFM1 were determined by enzyme-linked immunosorbent assay. AFM1 was detected in 46 % of all urine samples at a range of 31-348 pg/mL. The median and mean concentration of AFM1 in urine was 61 and 80 ± 60 pg/mL, respectively. A significant difference (p < 0.05) was found at the mean level of AFM1 between the rural (99 ± 71 pg/mL) and urban (54 ± 15 pg/mL) cohort. Urinary AFM1 levels did not show significant correlations with food frequency data or age, gender and body mass index of the participants. Among them, the highest mean AFM1 level (101 ± 71 pg/mL) was observed in the 50-60 years age group. In conclusion, detection frequency and urinary AFM1 levels in the Bangladeshi adults support concerns regarding their dietary exposure to AFB1. These first data warrant further biomarker-based studies in children and in cohorts of other parts of the country.

  13. Plasma haptoglobin and immunoglobulins as diagnostic indicators of deoxynivalenol intoxication

    PubMed Central

    Kim, Eun-Joo; Cho, Joon-Hyoung; Ku, Hyun-Ok; Pyo, Hyun-Mi; Kang, Hwan-Goo; Choi, Kyoung-Ho

    2008-01-01

    This study aimed to discover potential biomarkers for dioxynivalenol (DON) intoxication. B6C3F1 male mice were orally exposed to 0.83, 2.5 and 7.5 mg/kg body weight (bw) DON for 8 days and the differential protein expressions in their blood plasma were determined by SELDI - Time-of-Flight/Mass Spectrometry (TOF/MS) and the immunoglobulins (Igs) G, A, M and E in the serum were investigated. 11.7 kDa protein was significantly highly expressed according to DON administration and this protein was purified by employing a methyl ceramic HyperD F column with using optimization buffer for adsorption and desorption. The purified protein was identified as a haptoglobin precursor by peptide mapping with using LC/Q-TOF/MS and MALDI-TOF/MS and this was confirmed by western blotting and ELISA. IgG and IgM in serum were decreased in a dose-dependent manner and IgA was decreased at 7.5 mg/kg bw DON administration, but the IgE level was not changed. To compare the expressions of haptoglobin and the Igs patterns between aflatoxin B1 (AFB1), zearalenone (ZEA) and DON intoxications, rats were orally administered with AFB1 1.0, ZEA 240 and DON 7.5 mg/kg bw for 8 days. Haptoglobin was increased only at DON 7.5 mg/kg bw, while it was slightly decreased at ZEA 240 mg/kg bw and it was not detected at all at AFB1 1.0 mg/kg bw. IgG and IgA were decreased by DON, but IgG, IgA, IgM and IgE were all increased by AFB1. No changes were observed by ZEA administration. These results show that plasma haptoglobin could be a diagnostic biomarker for DON intoxication when this is combined with examining the serum Igs. PMID:18716445

  14. Determinants of formation of aflatoxin-albumin adducts: a seven-township study in Taiwan

    PubMed Central

    Sun, C-A; Wu, D-M; Wang, L-Y; Chen, C-J; You, S-L; Santella, R M

    2002-01-01

    Dietary exposure to aflatoxins is one of the major risk factors for hepatocellular carcinoma. Individual susceptibility to aflatoxin-induced hepatocarcinogenesis may be modulated by both genetic and environmental factors affecting metabolism. A cross-sectional study was performed to evaluate determinants of the formation of aflatoxin covalently bound to albumin (AFB1-albumin adducts). A total of 474 subjects who were free of liver cancer and cirrhosis and were initially selected as controls for previous case–control studies of aflatoxin-induced hepatocarcinogenesis in Taiwan, were employed in this study. Aflatoxin-albumin adducts were determined by competitive enzyme-linked immunosorbent assay, hepatitis B surface antigen and antibodies to hepatitis C virus by enzyme immunoassay, as well as genotypes of glutathione S-transferase M1-1 and T1-1 by polymerase chain reaction. The detection rate of AFB1-albumin adducts was significantly higher in males (42.5%) than in females (21.6%) (multivariate-adjusted odds ratio=2.6, 95% confidence interval=1.4–5.0). The formation of detectable albumin adducts was moderately higher in hepatitis B surface antigen carriers (42.8%) than in non-carriers (36.6%) (multivariate-adjusted odds ratio=1.4, 95% confidence interval=1.0–2.1). In addition, the detection rate of AFB1-albumin adducts tended to increase with the increasing number of null genotypes of glutathione S-transferase M1-1 and glutathione S-transferase T1-1. In conclusion, this cross-sectional study has assessed the relative contributions of environmental exposure and host susceptibility factors in the formation of AFB1-albumin adducts in a well characterised Chinese adult population. This study further emphasises the necessity to reduce aflatoxin exposure in people living in an area endemic for chronic hepatitis B virus infection. British Journal of Cancer (2002) 87, 966–970. doi:10.1038/sj.bjc.6600584 www.bjcancer.com © 2002 Cancer Research UK PMID:12434285

  15. Aflatoxins ingestion and canine mammary tumors: There is an association?

    PubMed

    Frehse, M S; Martins, M I M; Ono, E Y S; Bracarense, A P F R L; Bissoqui, L Y; Teixeira, E M K; Santos, N J R; Freire, R L

    2015-10-01

    The aim of this study was to determine the presence of mycotoxins on dogs feed and to explore the potential association between mycotoxins exposure and the chance of mamary tumors in a case-control study. The study included 256 female dogs from a hospital population, 85 with mammary tumors (case group) and 171 without mammary tumors (control group). An epidemiological questionnaire was applied to both groups, and the data were analyzed by the EpiInfo statistical package. For the study, 168 samples of the feed offered to dogs were analyzed for the presence of aflatoxins, fumonisins and zearalenone by high-performance liquid chromatography. Mycotoxins were found in 79 samples (100%) in the case group and 87/89 (97.8%) in the control group. Mycotoxins were detected in all types of feed, regardless feed quality. Level of aflatoxin B1 (p = 0.0356, OR = 2.74, 95%, CI 1.13 to 6.60), aflatoxin G1 (AFG1) (p = 0.00007, OR = 4.60, 95%, CI = 2.16 to 9.79), and aflatoxin G2 (AFG2) (p = 0.0133, OR = 9.91, 95%, CI 1.21 to 81.15) were statistically higher in case of mammary cancer. In contrast, neutering was a protective factor for mammary cancer (p = 0.0004, OR = 0.32, 95%, CI = 0.17 to 0.60).

  16. MicroRNA393 is involved in nitrogen-promoted rice tillering through regulation of auxin signal transduction in axillary buds

    PubMed Central

    Li, Xiang; Xia, Kuaifei; Liang, Zhen; Chen, Kunling; Gao, Caixia; Zhang, Mingyong

    2016-01-01

    Rice tillering has an important influence on grain yield, and is promoted by nitrogen (N) fertilizer. Several genes controlling rice tillering, which are regulated by poor N supply, have been identified. However, the molecular mechanism associated with the regulation of tillering based on N supply is poorly understood. Here, we report that rice microRNA393 (OsmiR393) is involved in N-mediated tillering by decreasing auxin signal sensitivity in axillary buds. Expression analysis showed that N fertilizer causes up-regulation of OsmiR393, but down-regulation of two target genes (OsAFB2 and OsTB1). In situ expression analysis showed that OsmiR393 is highly expressed in the lateral axillary meristem. OsmiR393 overexpression mimicked N-mediated tillering in wild type Zhonghua 11 (ZH11). Mutation of OsMIR393 in ZH11 repressed N-promoted tillering, which simulated the effects of limited N, and this could not be restored by supplying N fertilizer. Western blot analysis showed that OsIAA6 was accumulated in both OsmiR393-overexpressing lines and N-treated wild type rice, but was reduced in the OsMIR393 mutant. Therefore, we deduced that N-induced OsmiR393 accumulation reduces the expression of OsTIR1 and OsAFB2, which alleviates sensitivity to auxin in the axillary buds and stabilizes OsIAA6, thereby promoting rice tillering. PMID:27574184

  17. Fungal Aflatoxins Reduce Respiratory Mucosal Ciliary Function

    PubMed Central

    Lee, Robert J.; Workman, Alan D.; Carey, Ryan M.; Chen, Bei; Rosen, Phillip L.; Doghramji, Laurel; Adappa, Nithin D.; Palmer, James N.; Kennedy, David W.; Cohen, Noam A.

    2016-01-01

    Aflatoxins are mycotoxins secreted by Aspergillus flavus, which can colonize the respiratory tract and cause fungal rhinosinusitis or bronchopulmonary aspergillosis. A. flavus is the second leading cause of invasive aspergillosis worldwide. Because many respiratory pathogens secrete toxins to impair mucociliary immunity, we examined the effects of acute exposure to aflatoxins on airway cell physiology. Using air-liquid interface cultures of primary human sinonasal and bronchial cells, we imaged ciliary beat frequency (CBF), intracellular calcium, and nitric oxide (NO). Exposure to aflatoxins (0.1 to 10 μM; 5 to 10 minutes) reduced baseline (~6–12%) and agonist-stimulated CBF. Conditioned media (CM) from A. fumigatus, A. niger, and A. flavus cultures also reduced CBF by ~10% after 60 min exposure, but effects were blocked by an anti-aflatoxin antibody only with A. flavus CM. CBF reduction required protein kinase C but was not associated with changes in calcium or NO. However, AFB2 reduced NO production by ~50% during stimulation of the ciliary-localized T2R38 receptor. Using a fluorescent reporter construct expressed in A549 cells, we directly observed activation of PKC activity by AFB2. Aflatoxins secreted by respiratory A. flavus may impair motile and chemosensory functions of airway cilia, contributing to pathogenesis of fungal airway diseases. PMID:27623953

  18. MicroRNA393 is involved in nitrogen-promoted rice tillering through regulation of auxin signal transduction in axillary buds

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Xia, Kuaifei; Liang, Zhen; Chen, Kunling; Gao, Caixia; Zhang, Mingyong

    2016-08-01

    Rice tillering has an important influence on grain yield, and is promoted by nitrogen (N) fertilizer. Several genes controlling rice tillering, which are regulated by poor N supply, have been identified. However, the molecular mechanism associated with the regulation of tillering based on N supply is poorly understood. Here, we report that rice microRNA393 (OsmiR393) is involved in N-mediated tillering by decreasing auxin signal sensitivity in axillary buds. Expression analysis showed that N fertilizer causes up-regulation of OsmiR393, but down-regulation of two target genes (OsAFB2 and OsTB1). In situ expression analysis showed that OsmiR393 is highly expressed in the lateral axillary meristem. OsmiR393 overexpression mimicked N-mediated tillering in wild type Zhonghua 11 (ZH11). Mutation of OsMIR393 in ZH11 repressed N-promoted tillering, which simulated the effects of limited N, and this could not be restored by supplying N fertilizer. Western blot analysis showed that OsIAA6 was accumulated in both OsmiR393-overexpressing lines and N-treated wild type rice, but was reduced in the OsMIR393 mutant. Therefore, we deduced that N-induced OsmiR393 accumulation reduces the expression of OsTIR1 and OsAFB2, which alleviates sensitivity to auxin in the axillary buds and stabilizes OsIAA6, thereby promoting rice tillering.

  19. Aflatoxin metabolism in humans: detection of metabolites and nucleic acid adducts in urine by affinity chromatography

    SciTech Connect

    Groopman, J.D.; Donahue, P.R.; Zhu, J.Q.; Chen, J.S.; Wogan, G.N.

    1985-10-01

    A high-affinity IgM monoclonal antibody specific for aflatoxins was covalently bound to Sepharose 4B and used as a preparative column to isolate aflatoxin derivatives from the urine of people and experimental animals who had been exposed to the carcinogen environmentally or under laboratory conditions. Aflatoxin levels were quantified by radioimmunoassay and high-performance liquid chromatography after elution from the affinity column. In studies on rats injected with ( UC)aflatoxin B1, the authors identified the major aflatoxin-DNA adduct, 2,3-dihydro-2-(N7-guanyl)-3-hydroxy-aflatoxin B1 (AFB1-N7-Gua), and the oxidative metabolites M1 and P1 as the major aflatoxin species present in the urine. When this methodology was applied to human urine samples obtained from people from the Guangxi Province of China exposed to aflatoxin B1 through dietary contamination, the aflatoxin metabolites detected were also AFB1-N7-Gua and aflatoxins M1 and P1. Therefore, affinity chromatography using a monoclonal antibody represents a useful and rapid technique with which to isolate this carcinogen and its metabolites in biochemical epidemiology and for subsequent quantitative measurements, providing exposure information that can be used for risk assessment.

  20. Aflatoxin B1 induced hepatic neoplasia in Great Lakes coho salmon

    SciTech Connect

    Black, J.J.; Maccubbin, A.E.; Myers, H.K.; Zeigel, R.F.

    1988-11-01

    There is considerable interest in the development of fish models for carcinogen bioassays and the study of chemically induced cancer in wild fish species. Among salmonid species, rainbow trout have mainly been used for carcinogenesis research, in part due to the role played by this species in the discovery of the carcinogenic action of aflatoxin B1 (AFB1). Recently, apparatus and methodology for microinjection of salmonid fish embryos with chemical carcinogens has been described. Because eggs produced by Pacific salmon are relatively much larger than those of rainbow trout, they would provide an attractive subject for embryo microinjection. The Great Lakes are annually stocked with large numbers of coho salmon. It has been recommended to use coho salmon as an indicator for monitoring ecosystem health in the Great Lakes, because stockings throughout health in the Great Lakes, because stockings throughout the Great Lakes are from a common genetic strain and in the lake environment they have a defined food source and life cycle. These considerations led the authors to test coho salmon for their sensitivity to the potent hepatocarcinogen, AFB1. The present report describes in preliminary form, the results of these experiments.

  1. Correlation between mixed-function oxidase enzyme induction and aflatoxin B/sub 1/-induced unscheduled DNA synthesis in the chick embryo, in vivo

    SciTech Connect

    Hamilton, J.W.; Bloom, S.E.

    1984-01-01

    The unscheduled DNA synthesis (UDS) technique has been adapted for use in the chick embryo, in vivo, to determine the relationship between induction of the mixed-function oxidase (MFO) enzyme system and genetic damage from an indirect-acting mutagen-carcinogen. Embryos were injected at 6 days of incubation (DI) with either phenobarbital (PB), a specific inducer of P-450-associated enzyme activities, or 3,4,3',4'-tetrachlorobiphenyl (TCB), a specific inducer of P/sub 1/-450-associated enzyme activities. Aflatoxin B/sub 1/ (AFB1) was injected 24 hr later (7 DI), followed by a 5-hr continuous /sup 3/H-thymidine exposure. The livers were removed, prepared for autoradiography, and hepatocytes were scored for an increase in grains/nucleus, indicative of UDS. Aflatoxin B/sub 1/ caused a dose-related increase in UDS in all control and induction groups. Phenobarbital-induced embryos had an increased UDS response while TCB-induced embryos had a decreased UDS response, relative to noninduced embryos, for each dosage of AFB1. This suggests that the genotoxicity of an indirect-acting mutagen-carcinogen can be either increased or decreased, in vivo, depending on the inducer used. The chick embryo provides an excellent system for studying the effect of MFO induction on the genotoxicity of promutagen-carcinogens in a developing system.

  2. AFM1 in Milk: Physical, Biological, and Prophylactic Methods to Mitigate Contamination

    PubMed Central

    Giovati, Laura; Magliani, Walter; Ciociola, Tecla; Santinoli, Claudia; Conti, Stefania; Polonelli, Luciano

    2015-01-01

    Aflatoxins (AFs) are toxic, carcinogenic, immunosuppressive secondary metabolites produced by some Aspergillus species which colonize crops, including many dietary staple foods and feed components. AFB1 is the prevalent and most toxic among AFs. In the liver, it is biotransformed into AFM1, which is then excreted into the milk of lactating mammals, including dairy animals. AFM1 has been shown to be cause of both acute and chronic toxicoses. The presence of AFM1 in milk and dairy products represents a worldwide concern since even small amounts of this metabolite may be of importance as long-term exposure is concerned. Contamination of milk may be mitigated either directly, decreasing the AFM1 content in contaminated milk, or indirectly, decreasing AFB1 contamination in the feed of dairy animals. Current strategies for AFM1 mitigation include good agricultural practices in pre-harvest and post-harvest management of feed crops (including storage) and physical or chemical decontamination of feed and milk. However, no single strategy offers a complete solution to the issue. PMID:26512694

  3. Is Gamma Radiation Suitable to Preserve Phenolic Compounds and to Decontaminate Mycotoxins in Aromatic Plants? A Case-Study with Aloysia citrodora Paláu.

    PubMed

    Pereira, Eliana; Barros, Lillian; Antonio, Amilcar L; Cabo Verde, Sandra; Santos-Buelga, Celestino; Ferreira, Isabel C F R; Rodrigues, Paula

    2017-02-23

    This study aimed to determine the effect of gamma radiation on the preservation of phenolic compounds and on decontamination of dry herbs in terms of ochratoxin A (OTA) and aflatoxin B1 (AFB1), using Aloysia citrodora Paláu as a case study. For this purpose, artificially contaminated dry leaves were submitted to gamma radiation at different doses (1, 5, and 10 kGy; at dose rate of 1.7 kGy/h). Phenolic compounds were analysed by HPLC-DAD-ESI/MS and mycotoxin levels were determined by HPLC-fluorescence. Eleven phenolic compounds were identified in the samples and despite the apparent degradation of some compounds (namely verbasoside), 1 and 10 kGy doses point to a preservation of the majority of the compounds. The mean mycotoxin reduction varied between 5.3% and 9.6% for OTA and from 4.9% to 5.2% for AFB1. It was not observed a significant effect of the irradiation treatments on mycotoxin levels, and a slight degradation of the phenolic compounds in the irradiated samples was observed.

  4. Exposure assessment of mycotoxins in cow's milk in Argentina.

    PubMed

    Signorini, M L; Gaggiotti, M; Molineri, A; Chiericatti, C A; Zapata de Basílico, M L; Basílico, J C; Pisani, M

    2012-02-01

    A stochastic simulation model was developed to carry out the first quantitative risk exposure assessment of the mycotoxin level in cow's milk produced in Argentina. The prevalence and concentration of aflatoxin M1 (AFM1), deoxynivalenol (DON) and zearalenone (ZEA) were modeled at various stages through milk processes complying with Argentinean practices. Concentration of AFM1 (0.059ppb), DON (0.338ppb) and ZEA (0.125ppb) in dairy milk were estimated. The proportion of feed samples that exceeded the maximum level accepted by European regulations for AFB1, DON and ZEA were estimated at 25.07%, 0.0% and 8.9%, respectively. The percentage of milk samples that exceeded the maximum level accepted for AFB1 by the MERCOSUR (0.5ppb) and the European Union regulations (0.05ppb) were 0.81 and 32.65, respectively. The probability distribution of AFM1 concentration in milk was affected by the carry-over rate equations applied in the model. Mycotoxin levels in corn silage and concentrated feeds were the factors most correlated with mycotoxin concentrations in milk. Therefore, agricultural practices, crop management and feed production require prompt attention regarding mycotoxin issues.

  5. Inhibition of mycotoxin-producing fungi by Bacillus strains isolated from fish intestines.

    PubMed

    Veras, Flávio Fonseca; Correa, Ana Paula Folmer; Welke, Juliane Elisa; Brandelli, Adriano

    2016-12-05

    Bacillus strains isolated from the aquatic environment of the Brazilian Amazon region were tested for their activity against mycotoxigenic fungi. All tested bacteria showed antifungal activity, inhibiting at least 7 indicator fungi. Four Bacillus strains showing promising antifungal results were subsequently evaluated for their activity in reducing mycelial growth rate, sporulation, spore germination percentage, and mycotoxin production. Bacillus sp. P1 and Bacillus sp. P11 had a remarkable antifungal effect on toxigenic fungi. Washed bacterial cell suspension of strains P1 and P11 (10(7)CFU/ml) reduced by >70% the fungal colony diameters, including a complete inhibition of ochratoxin A (OTA) producing Aspergillus spp. Significant reduction of growth rate, sporulation and spore germination were also observed. The bacteria influenced the production of mycotoxins, causing a reduction around 99 and 97% in AFB1 and OTA concentration, respectively. Chromatographic analysis revealed the presence of lipopeptides (iturin A and surfactin isomers) in butanol extracts of cell-free supernatants and cell pellets of strains P1 and P11. Furthermore, antifungal activity of these extracts was confirmed against A. flavus A12 and A. carbonarius ITAL293, producers of AFB1 and OTA, respectively. These bacterial strains could be promising biocontrol agents against toxigenic fungi.

  6. Altered biochemical profile and gene expression in aflatoxin B-1-transformed C3H10T1/2 cells.

    PubMed

    Nadadur, S; Lisciandro, K; Mudipalli, A; Maccubbin, A; Faletto, M; Gurtoo, H

    1997-06-01

    A transformed cell line 7SA, obtained by transformation of C3H10T1/2 cells with irt vitro activated aflatoxin B-1 (AFB(1)), was used to investigate biochemical and molecular alterations associated with transformation by AFB(1). 7SA cells demonstrate an altered biochemical phenotype characterized by alterations in phase I and phase II enzymes in a manner that would allow these cells to survive in a hostile chemical environment. Investigations of the molecular basis of transformation revealed no mutations in codons 12/13 and 61 of ras genes (Ha-, Ki- and N-ras) and in exons 5, 6, 7 and 8 of p53 tumor suppressor gene. However, subtractive hybridization led to the isolation of seven novel cDNA clones that demonstrated 2 to 10-fold overexpression of the mRNAs corresponding to the five cDNAs (SK1, SK2, SK3, SK4 and SK5) and >400 fold overexpression of the mRNAs corresponding to the other two cDNAs (SK67 and SK153). In addition, part of the sequence of the cDNA clone SK5 demonstrated >88% identity with L1-like mobile genetic element and Southern analysis of the DNA with SK5 cDNA as a probe revealed gene rearrangement in 7SA DNA, compared to DNA from C3H10T1/2 cells.

  7. Key roles of vitamins A, C, and E in aflatoxin B1-induced oxidative stress.

    PubMed

    Alpsoy, Lokman; Yalvac, Mehmet Emir

    2011-01-01

    Aflatoxins (Aspergillus flavus toxins) are one of the natural toxic molecules which are produced by a group of fungi called Aspergillus. Foods and drinks contaminated with aflatoxins cause global health and environmental problems. Today in many developing countries, these toxins are leading cause of some liver cancers and serious gastrointestinal problems. Aflatoxins, which are well known to be mutagenic, carcinogenic, hepatotoxic, and immunosuppressive, exert inhibitory effects on biological processes including DNA synthesis, DNA-dependent RNA synthesis, DNA repair, and protein synthesis. Aflatoxins B(1) (AFB(1)) is the most widespread oxidative agent of the aflatoxins. Numerous diverse compounds and extracts have been reported to reduce the aflatoxins induced oxidative stress in the body. Most of these inhibitors including phenylpropanoids, terpenoids, alkaloids, and vitamins are originally derived from plants. Among these, being essential biomolecules, vitamins are used as coenzymes in very significant biological reactions. They also function as nonenzymatic antioxidative agents protecting the cells from oxidative stress-induced toxicity and transformation. This chapter reviews the mechanism of AFB(1)-induced oxidative stress and focuses on the protective effects of vitamins A, C, and E on reducing this stress.

  8. Protective role of sodium selenite on histopathological lesions, decreased T-cell subsets and increased apoptosis of thymus in broilers intoxicated with aflatoxin B₁.

    PubMed

    Chen, Kejie; Shu, Gang; Peng, Xi; Fang, Jing; Cui, Hengmin; Chen, Jin; Wang, Fengyuan; Chen, Zhengli; Zuo, Zhicai; Deng, Junliang; Geng, Yi; Lai, Weimin

    2013-09-01

    For evaluating the ability of selenium (Se) in counteracting the adverse effects of aflatoxin B₁ (AFB₁), two hundred 1-day-old male Avian broilers, divided into five groups, were fed with basal diet (control group), 0.3 mg/kg AFB₁ (AFB₁ group), 0.3 mg/kg AFB₁+0.2 mg/kg Se (+Se group I), 0.3mg/kg AFB₁+0.4 mg/kg Se (+Se group II) and 0.3mg/kg AFB₁+0.6 mg/kg Se (+Se group III), respectively. Compared with control group, the decreased relative weight of thymus and percentages of mature thymocytes, congestion in medulla and much debris in cortex of thymus, and the increased apoptotic thymocytes were observed in AFB1 group. However, supplied dietary sodium selenite could increase the relative weight of thymus and percentages of mature thymocytes, and alleviate histopathological lesions. Compared with AFB1 group, the percentages of apoptotic thymocytes detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method and flow cytometry method in three +Se groups were decreased, the expression of Caspase-3 and Bax, through quantitative real-time PCR and immunohistochemical method, in three +Se groups were decreased, while the expression of Bcl-2 was increased. The results indicate that sodium selenite supplied in the diet, through a mechanism of apoptosis regulation, may ameliorated AFB₁-induced lesions of thymus and accordingly improve the impaired cellular immune function.

  9. Mycoflora and incidence of aflatoxin B1, zearalenone and deoxynivalenol in poultry feeds in Argentina.

    PubMed

    Dalcero, A; Magnoli, C; Chiacchiera, S; Palacios, G; Reynoso, M

    1997-01-01

    In Argentina, there is rather little information about the natural occurrence of mycotoxins in feedstuffs. The aim of this work was to determine the fungal flora and natural incidence of aflatoxin B1 (AFB1), zearalenone (ZEA) and deoxynivalenol (DON) in poultry feeds from 5 factories of Río Cuarto, Córdoba. Three hundred samples were taken from May 1995 to May 1996. Fungal counts of poultry feeds ranged 10(4) to 10(6) CFU g-1. The lowest counts were obtained on the first months from the sampling (May to September 1995) with mean values significantly different from those found at the last of the sampling (October 1995 to April 1996). The most prevalent species isolated of poultry feed samples belonged to the genera Penicillium that was present in 98% of the samples, Fusarium (87%) and Aspergillus (52%). Fusarium species isolated were: F moniliforme in 73% of the samples, F subglutinans (35%), F graminearum (20%) and within Aspergillus species: A. parasiticus (33%) and A. flavus (8%) were identified. In poultry feeds aflatoxin B1 (AFB1) was the most significant mycotoxin with levels ranging from 17 to 197 ng/g. For deoxynivalenol (DON) the levels ranged from 240 to 410 ng/g. Only three out of 300 samples were contaminated with zearalenone (ZEA) in concentrations of 30, 120 and 280 ng/g. These are preliminary data on this subject in our region.

  10. Aspergillus section Flavi and aflatoxins in Algerian wheat and derived products.

    PubMed

    Riba, Amar; Bouras, Noureddine; Mokrane, Salim; Mathieu, Florence; Lebrihi, Ahmed; Sabaou, Nasserdine

    2010-10-01

    Wheat and its derivatives are a very important staple food for North African populations. The aim of this study was to analyze populations of Aspergillus section Flavi from local wheat based on aflatoxins (AFs), cyclopiazonic acid (CPA) and sclerotia production, and also to evaluate AFs-contaminated wheat collected from two different climatic regions in Algeria. A total of 108 samples of wheat were collected during the following phases: pre-harvest, storage in silos and after processing. The results revealed that among the Aspergillus species isolated, those belonging to section Flavi were predominant. Of the 150 strains of Aspergillus section Flavi isolated, 144 were identified as Aspergillus flavus and 6 as Aspergillus tamarii. We showed that 72% and 10% of the A. flavus strains produced AFs and CPA, respectively. Among the 150 strains tested, 60 produced amounts of AFB1 ranging from 12.1 to 234.6 microg/g of CYA medium. Also, we showed that most strains produced large sclerotia. AFB1was detected by HPLC in 56.6% of the wheat samples and derived products (flour, semolina and bran) with contamination levels ranging from 0.13 to 37.42 microg/kg.

  11. Limited survey for the occurrence of aflatoxins in cereals and poultry feeds from Rabat, Morocco.

    PubMed

    Zinedine, A; Juan, C; Soriano, J M; Moltó, J C; Idrissi, L; Mañes, J

    2007-04-01

    Fifty eight (58) samples of cereals for human consumption (20 corn flour, 17 wheat flour) and poultry feeds (n=21) purchased from popular markets of Rabat in Morocco were analyzed for aflatoxins (AF) by HPLC with immunoaffinity column (IAC) clean-up and fluorimetric detection. The incidence of AF in corn, wheat flour and poultry feeds was about 80, 17.6 and 66.6% respectively. High contamination levels were found in corn and poultry feeds samples. Levels of contamination of analyzed samples with AFB1 ranged from 0.23 to 11.2, 0.03 to 0.15 and 0.05 to 5.38 ng/g for corn, wheat and poultry feeds respectively. Results showed also that the contamination of 10% of samples of corn was higher than the limit set by EU regulations for AFB1 and total AF. This is the first report on the determination of AF in corn, wheat and poultry feeds from Morocco by HPLC and IAC.

  12. Effects of temperature, water activity and incubation time on fungal growth and aflatoxin B1 production by toxinogenic Aspergillus flavus isolates on sorghum seeds.

    PubMed

    Lahouar, Amani; Marin, Sonia; Crespo-Sempere, Ana; Saïd, Salem; Sanchis, Vicente

    2016-01-01

    Sorghum, which is consumed in Tunisia as human food, suffers from severe colonization by several toxigenic fungi and contamination by mycotoxins. The Tunisian climate is characterized by high temperature and humidity that stimulates mold proliferation and mycotoxin accumulation in foodstuffs. This study investigated the effects of temperature (15, 25 and 37°C), water activity (aw, between 0.85 and 0.99) and incubation time (7, 14, 21 and 28 d) on fungal growth and aflatoxin B1 (AFB1) production by three Aspergillus flavus isolates (8, 10 and 14) inoculated on sorghum grains. The Baranyi model was applied to identify the limits of growth and mycotoxin production. Maximum diameter growth rates were observed at 0.99 a(w) at 37°C for two of the isolates. The minimum aw needed for mycelial growth was 0.91 at 25 and 37°C. At 15°C, only isolate 8 grew at 0.99 a(w). Aflatoxin B1 accumulation could be avoided by storing sorghum at low water activity levels (≤0.91 a(w)). Aflatoxin production was not observed at 15°C. This is the first work on the effects of water activity and temperature on A. flavus growth and AFB1 production by A. flavus isolates on sorghum grains.

  13. Multi-Mycotoxin Analysis in Durum Wheat Pasta by Liquid Chromatography Coupled to Quadrupole Orbitrap Mass Spectrometry

    PubMed Central

    Tolosa, Josefa; Graziani, Giulia; Gaspari, Anna; Chianese, Donato; Ferrer, Emilia; Mañes, Jordi; Ritieni, Alberto

    2017-01-01

    A simple and rapid multi-mycotoxin method for the determination of 17 mycotoxins simultaneously is described in the present survey on durum and soft wheat pasta samples. Mycotoxins included in the study were those mainly reported in cereal samples: ochratoxin-A (OTA), aflatoxin B1 (AFB1), zearalenone (ZON), deoxynivalenol (DON), 3-and 15-acetyl-deoxynivalenol (3-AcDON and 15-AcDON), nivalenol (NIV), neosolaniol (NEO), fusarenon-X, (FUS-X), T-2 toxin (T-2) and HT-2 toxin (HT-2), fumonisin B1 and B2 (FB1 and FB2), and four emerging mycotoxins: three enniatins (ENA, ENA1, and ENB), and beauvericin (BEA). Twenty-nine samples were analyzed to provide an overview on mycotoxin presence: 27 samples of durum wheat pasta, and two samples of baby food. Analytical results concluded that trichothecenes showed the highest incidence, mainly DON, NIV, and HT-2 toxin, followed by ZON and ENB, while NEO, FUS-X, OTA, AFB1, and FUM were not detected in any sample. The highest contents corresponded to ENB and ranged from 91.15 µg/kg to 710.90 µg/kg. PMID:28208797

  14. Identification and characterization of chlorin e(4) ethyl ester in sera of individuals participating in the chlorophyllin chemoprevention trial.

    PubMed

    Egner, P A; Stansbury, K H; Snyder, E P; Rogers, M E; Hintz, P A; Kensler, T W

    2000-09-01

    Chlorophyllin (CHL), a mixture of water soluble derivatives of chlorophyll, has been shown to be an effective inhibitor of aflatoxin B(1) (AFB(1)) carcinogenesis and AFB(1)-DNA adduct formation in rainbow trout and rats [Breinholt, V., Hendricks, J., Pereira, C., Arbogast, D., and Bailey, G. (1995) Cancer Res. 55, 57-62; Kensler, T. W., Groopman, J. D., and Roebuck, B. D. (1998) Mutat. Res. 402, 165-172]. The chemopreventive action of CHL has been previously attributed to molecular complexing. In 1997, a randomized, double-blind clinical trial of CHL was conducted in Qidong, Jiangsu Province, People's Republic of China. At the completion of the study, when serum samples were regrouped by subject identification number, it was noted that many of the participant samples were green in color. Using HPLC, ESI/MS, and MS/MS techniques, serum samples from individuals receiving CHL were found to contain previously unreported copper chlorin e(4) ethyl ester (CuCle(4) ethyl ester) as well as copper chlorin e(4) (CuCle(4)). Both chlorins originated in the study tablet, were absorbed into the bloodstream, and conferred a green color to the sera. This initial finding of in vivo absorption and bioavailability of two chlorin derivatives suggests that the mechanism of CHL chemoprevention may lie in the actions of these two components in vivo in addition to preventing carcinogen absorption from the gut.

  15. Differential repair of DNA damage in specific nucleotide sequences in monkey cells.

    PubMed Central

    Leadon, S A

    1986-01-01

    An immunological method was developed that isolates DNA fragments containing bromouracil in repair patches from unrepaired DNA using a monoclonal antibody that recognizes bromouracil. Cultured monkey cells were exposed to either UV light or the activated carcinogen aflatoxin B1 and excision repair of damage in DNA fragments containing the integrated and transcribed E. coli gpt gene was compared to that in the genome overall. A more rapid repair, of both UV and AFB1 damage was observed in the DNA fragments containing the E. coli gpt genes. The more efficient repair of UV damage was not due to a difference in the initial level of pyrimidine dimers as determined with a specific UV endonuclease. Consistent with previous observations using different methodology, repair of UV damage in the alpha sequences was found to occur at the same rate as that in the genome overall, while repair of AFB1 damage was deficient in alpha DNA. The preferential repair of damage in the gpt gene may be related to the functional state of the sequence and/or to alterations produced in the chromatin conformation by the integration of plasmid sequences carrying the gene. Images PMID:3786142

  16. Effect of Carum copticum essential oil on growth and aflatoxin formation by Aspergillus strains.

    PubMed

    Kazemi, M

    2015-01-01

    The objectives of this study were to determine the antiaflatoxin B1 activity in vitro of the essential oil (EO) extracted from the seeds of Carum copticum and to evaluate its antifungal activity in vivo as a potential food preservative. The C. copticum EO exhibited noticeable inhibition on dry mycelium and synthesis of aflatoxin B1 (AFB1) by Aspergillus flavus, completely inhibiting AFB1 production at 4 μL/mL. C. copticum EOs showed the lowest percentages of decayed cherry tomatoes for all fungi compared with the control at 100 μL/mL with values of 5.01 ± 67% for A. flavus and 5.98 ± 54% for Aspergillus niger. The results indicated that the percentage of infected fruits is significantly (p < 0.01) reduced by the EO at 16°C for 30 days. In this case, the oil at 100 μL/mL concentration showed the highest inhibition of fungal infection with a value of 80.45% compared with the control. Thus, the EO of dill could be used to control food spoilage and as a potential source of food preservative.

  17. Investigations on the Antifungal Effect of Nerol against Aspergillus flavus Causing Food Spoilage

    PubMed Central

    Tian, Jun; Zeng, Xiaobin; Zeng, Hong; Feng, Zhaozhong; Miao, Xiangmin; Peng, Xue

    2013-01-01

    The antifungal efficacy of nerol (NEL) has been proved against Aspergillus flavus by using in vitro and in vivo tests. The mycelial growth of A. flavus was completely inhibited at concentrations of 0.8 μL/mL and 0.1 μL/mL NEL in the air at contact and vapor conditions, respectively. The NEL also had an evident inhibitory effect on spore germination in A. flavus along with NEL concentration as well as time-dependent kinetic inhibition. The NEL presented noticeable inhibition on dry mycelium weight and synthesis of aflatoxin B1 (AFB1) by A. flavus, totally restraining AFB1 production at 0.6 μL/mL. In real food system, the efficacy of the NEL on resistance to decay development in cherry tomatoes was investigated in vivo by exposing inoculated and control fruit groups to NEL vapor at different concentration. NEL vapors at 0.1 μL/mL air concentration significantly reduced artificially contaminated A. flavus and a broad spectrum of fungal microbiota. Results obtained from presented study showed that the NEL had a great antifungal activity and could be considered as a benefit and safe tool to control food spoilage. PMID:24453813

  18. Aflatoxin exposure during the first 36 months of life was not associated with impaired growth in Nepalese children: An extension of the MAL-ED study

    PubMed Central

    Hsu, Hui-Husan; Chandyo, Ram Krishna; Shrestha, Binob; Bodhidatta, Ladaporn; Tu, Yu-Kang; Gong, Yun-Yun; Egner, Patricia A.; Ulak, Manjeswori; Groopman, John D.; Wu, Felicia

    2017-01-01

    Exposure to aflatoxin, a mycotoxin common in many foods, has been associated with child growth impairment in sub-Saharan Africa. To improve our understanding of growth impairment in relation to aflatoxin and other risk factors, we assessed biospecimens collected in Nepalese children at 15, 24, and 36 months of age for aflatoxin exposure. Children (N = 85) enrolled in the Bhaktapur, Nepal MAL-ED study encompassed the cohort analysed in this study. Exposure was assessed through a plasma biomarker of aflatoxin exposure: the AFB1-lysine adduct. The aflatoxin exposures in the study participants were compared to anthropometrics at each time period (length-for-age [LAZ], weight-for-age [WAZ], and weight-for-length [WLZ] z-scores), growth trajectories over time, age, and breastfeeding status. Results demonstrated chronic aflatoxin exposure in this cohort of children, with a geometric mean of 3.62 pg AFB1-lysine/mg albumin. However, the chronic aflatoxin exposure in this cohort was not significantly associated with anthropometric z-scores, growth trajectories, age, or feeding status, based on the available time points to assess aflatoxin exposure. Low mean levels of aflatoxin exposure and infrequent occurrence of stunting, wasting, or underweight z-score values in this cohort are possible contributing factors to a lack of evidence for an association. Further research is needed to examine whether a threshold dose of aflatoxin exists that could induce child growth impairment. PMID:28212415

  19. The antimutagenic activity of the major flavonoids of rooibos (Aspalathus linearis): some dose-response effects on mutagen activation-flavonoid interactions.

    PubMed

    Snijman, Petra W; Swanevelder, Sonja; Joubert, Elizabeth; Green, Ivan R; Gelderblom, Wentzel C A

    2007-07-28

    The antimutagenic properties of the most prevalent flavonoids in rooibos (Aspalathus linearis) were compared in the Salmonella typhimurium mutagenicity assay using tester strains TA98 and TA100 with, respectively, 2-acetamido-fluorene (2-AAF) and aflatoxin B(1) (AFB(1)) as mutagens in the presence of metabolic activation. The flavonoids included the dihydrochalcones aspalathin and nothofagin and their flavone analogues, orientin and isoorientin, and vitexin and isovitexin, respectively, as well as luteolin, chrysoeriol, (+)-catechin, quercetin, isoquercitrin, hyperoside and rutin. Flavonoid-mutagen interactions ranged from antimutagenic, comutagenic and promutagenic to mutagenic, while dose-response effects were mutagen-specific and ranged from typical to atypical including biphasic and threshold effects. Aspalathin and nothofagin and their structural flavonoid analogues displayed moderate antimutagenic properties while luteolin and to some extent, chrysoeriol, showed activities comparable to those of the green tea flavonoid (-) epigallocatechin gallate (EGCG). Apart from their mutagenic and promutagenic properties, quercetin and isoquercitrin exhibited concentration-dependent comutagenic and/or antimutagenic effects against 2-AAF- and AFB(1)-induced mutagenesis. Different structural parameters known to affect the antimutagenic properties of flavonoids include their hydrophilic or lipophilic nature due to the extent of hydroxylation and O-methylation, glycosylation on the A and B rings, the C4-keto group and the C2-C3 double bond. The C ring does not appear to be a prerequisite when comparing for the antimutagenic activity of the dihydrochalcones when compared of the dihydrochalcones with the structural flavone analogues.

  20. Ultra-performance liquid chromatography quadrupole time-of-flight MS for identification of electron beam from accelerator degradation products of aflatoxin B1.

    PubMed

    Wang, Ruiqi; Liu, Ruijie; Chang, Ming; Jin, Qingzhe; Huang, Jianhua; Liu, Yuanfa; Wang, Xingguo

    2015-02-01

    Electron beam irradiation was proven to be a successful method in aflatoxin degradation in earlier researches. However, the exact nature of the result radiation products generated by the aflatoxins remains unknown. Based on ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS) analysis, the solution of aflatoxin B1 (AFB1) in acetonitrile irradiated by electron beam degraded to two kinds of major products. The doses employed were in the range of 0 (control) to 8.60 kGy. The absorbed doses were monitored with FWT-60-00 radio-chromic dosimeters. By using UPLC-Q-TOF MS, accurate masses and proposed molecular formula for the degradation products, 261.1233 m/z (C14H13O5) and 299.1104 m/z (C17H15O5), were obtained from low mass error and high matching properties. Structural formula for the radio-degradation products and the degradation pathways leading to the compounds were proposed, based on the molecular formula and MS-MS spectra. The results showed that electron beam (EB) irradiation is an effective method for degrading AFB1.

  1. Interactions of chemical carcinogens and genetic variation in hepatocellular carcinoma

    PubMed Central

    Zhang, Yu-Jing

    2010-01-01

    In the etiology of hepatocellular carcinoma (HCC), in addition to hepatitis B virus and hepatitis C virus infections, chemical carcinogens also play important roles. For example, aflatoxin B1 (AFB1) epoxide reacts with guanine in DNA and can lead to genetic changes. In HCC, the tumor suppressor gene p53 codon 249 mutation is associated with AFB1 exposure and mutations in the K-ras oncogene are related to vinyl chloride exposure. Numerous genetic alterations accumulate during the process of hepatocarcinogenesis. Chemical carcinogen DNA-adduct formation is the basis for these genetic changes and also a molecular marker which reflects exposure level and biological effects. Metabolism of chemical carcinogens, including their activation and detoxification, also plays a key role in chemical hepatocarcinogenesis. Cytochrome p450 enzymes, N-acetyltransferases and glutathione S-transferases are involved in activating and detoxifying chemical carcinogens. These enzymes are polymorphic and genetic variation influences biological response to chemical carcinogens. This genetic variation has been postulated to influence the variability in risk for HCC observed both within and across populations. Ongoing studies seek to fully understand the mechanisms by which genetic variation in response to chemical carcinogens impacts on HCC risk. PMID:21160980

  2. The major volatile compound 2-phenylethanol from the biocontrol yeast, Pichia anomala, inhibits growth and expression of aflatoxin biosynthetic genes of Aspergillus flavus.

    PubMed

    Hua, Sui Sheng T; Beck, John J; Sarreal, Siov Bouy L; Gee, Wai

    2014-05-01

    Aspergillus flavus is a ubiquitous saprophyte that is able to produce the most potent natural carcinogenic compound known as aflatoxin B1 (AFB1). This toxin frequently contaminates crops including corn, cotton, peanuts, and tree nuts causing substantial economic loss worldwide. Consequently, more than 100 countries have strict regulations limiting AFB1 in foodstuffs and feedstuffs. Plants and microbes are able to produce volatile compounds that act as a defense mechanism against other organisms. Pichia anomala strain WRL-076 is a biocontrol yeast currently being tested to reduce AF contamination of tree nuts in California. We used the SPME-GC/MS analysis and identified the major volatile compound produced by this strain to be 2-phenylethanol (2-PE). It inhibited spore germination and AF production of A. flavus. Inhibition of AF formation by 2-PE was correlated with significant down regulation of clustering AF biosynthesis genes as evidenced by several to greater than 10,000-fold decrease in gene expression. In a time-course analysis we found that 2-PE also altered the expression patterns of chromatin modifying genes, MYST1, MYST2, MYST3, gcn5, hdaA and rpdA. The biocontrol capacity of P. anomala can be attributed to the production of 2-PE, which affects spore germination, growth, toxin production, and gene expression in A. flavus.

  3. Multi-component immunochromatographic assay for simultaneous detection of aflatoxin B1, ochratoxin A and zearalenone in agro-food.

    PubMed

    Li, Xin; Li, Peiwu; Zhang, Qi; Li, Ran; Zhang, Wen; Zhang, Zhaowei; Ding, Xiaoxia; Tang, Xiaoqian

    2013-11-15

    Mycotoxins are highly toxic contaminants and have induced health threat to human and animals. Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) commonly occur in food and feed. A multi-component immunochromatographic assay (ICA) was developed for rapid and simultaneous determination of these three mycotoxins in agro-food. The strategy was performed based on the competitive immunoreactions between antibody-colloidal gold nanoparticle conjugate probes and mycotoxins or mycotixin antigens. Each monoclonal antibody specially recognize its corresponding mycotoxin and antigen, and there was no cross reactivity in the assay. Three mycotixin antigens were immobilized as three test lines in the nitrocellulose membrane reaction zone, which enable the simultaneous detection in one single test. The visible ICA results were obtained in 20 min. The visual detection limits of this strip test for the AFB1, OTA and ZEA were 0.25 ng/mL, 0.5 ng/mL and 1 ng/mL, respectively. The assay was evaluated using spiked and naturally contaminated peanuts, maize and rice samples. The results were in accordance with those obtained using enzyme-linked immunosorbent assay. In summary, this developed ICA could provide an effective and rapid approach for onsite detection of multi-mycotoxin in agro-food samples without any expensive instrument.

  4. Aflatoxin B1-induced hepatocellular carcinoma in developing countries: Geographical distribution, mechanism of action and prevention

    PubMed Central

    HAMID, ABDU SELIM; TESFAMARIAM, ISAIAS GOITOM; ZHANG, YUCHENG; ZHANG, ZHEN GUI

    2013-01-01

    Hepatocellular carcinoma (HCC) is the most well-known primary liver malignancy worldwide. Its incidence is rising at alarming rates and has become a public concern globally. It is more frequent in developing countries than in industrialized countries with respect to geographical variation, ethnic disparities and socioeconomic status. Dietary exposure to aflatoxins is among the major HCC risk factors. Aflatoxin B1, which is a genotoxic hepatocarcinogen, which presumptively causes cancer by inducing DNA adducts leading to genetic changes in target liver cells. AFB1 is metabolized by cytochrome-P450 enzymes to the reactive intermediate AFB1-8, 9 epoxide (AFBO) which binds to liver cell DNA, resulting in DNA adducts. DNA adducts interact with the guanine bases of liver cell DNA and cause a mutational effect in the P53 tumor suppressor gene at the codon 249 hotspot in exon 7, which may lead to HCC. Approximately 4.5 billion of the world’s population is exposed to aflatoxin-contaminated food, particularly in low-income countries. Prevention involves treating crops that are susceptible to fungal contamination, appropriate handling of foodstuffs and the use of chemopreventive intervention. Moreover, an integrated network collaboration of different sectors, including public health, agricultural departments and mass media, is required to ensure effective food regulation systems so as to minimize the contamination of food by aflatoxins. PMID:23599745

  5. Incidence of aflatoxin M1 in human and animal milk in Jordan.

    PubMed

    Omar, Sharaf S

    2012-01-01

    This study was undertaken to determine the presence of aflatoxin M1 (AFM1) in animal milk. In addition, exposure of infants to aflatoxin M1 (AFM1) and lactating mothers to aflatoxin B1 (AFB1) was examined using AFM1 in breast milk as a biomarker for exposure to AFB1. In total, 100 samples of fresh animal milk and fermented milk (buttermilk) and 80 samples of human breast milk were collected during the period 2011-2012. An enzyme-linked immunosorbent assay (ELISA) was used for the analysis of milk samples. AFM1 was detected in all animal fresh and fermented milk samples. The concentrations of AFM1 in 70 samples of fresh and fermented milk were higher than the maximum tolerance limit accepted by the European Union and the United States of 50 ng/kg. In human milk samples the average concentration of AFM1 was higher than the maximum tolerance limit accepted by the European Union and the United States of 25 ng/kg. Logistic regression analysis failed to show a correlation between AFM1 and type and amount of dairy consumption, vegetables, fruits, and meat. However, an association between AFM1 and cereal consumption was detected. This study is the first to report on the occurrence of AFM1 in milk consumed by the Jordanian population.

  6. Aflatoxin exposure during the first 36 months of life was not associated with impaired growth in Nepalese children: An extension of the MAL-ED study.

    PubMed

    Mitchell, Nicole J; Hsu, Hui-Husan; Chandyo, Ram Krishna; Shrestha, Binob; Bodhidatta, Ladaporn; Tu, Yu-Kang; Gong, Yun-Yun; Egner, Patricia A; Ulak, Manjeswori; Groopman, John D; Wu, Felicia

    2017-01-01

    Exposure to aflatoxin, a mycotoxin common in many foods, has been associated with child growth impairment in sub-Saharan Africa. To improve our understanding of growth impairment in relation to aflatoxin and other risk factors, we assessed biospecimens collected in Nepalese children at 15, 24, and 36 months of age for aflatoxin exposure. Children (N = 85) enrolled in the Bhaktapur, Nepal MAL-ED study encompassed the cohort analysed in this study. Exposure was assessed through a plasma biomarker of aflatoxin exposure: the AFB1-lysine adduct. The aflatoxin exposures in the study participants were compared to anthropometrics at each time period (length-for-age [LAZ], weight-for-age [WAZ], and weight-for-length [WLZ] z-scores), growth trajectories over time, age, and breastfeeding status. Results demonstrated chronic aflatoxin exposure in this cohort of children, with a geometric mean of 3.62 pg AFB1-lysine/mg albumin. However, the chronic aflatoxin exposure in this cohort was not significantly associated with anthropometric z-scores, growth trajectories, age, or feeding status, based on the available time points to assess aflatoxin exposure. Low mean levels of aflatoxin exposure and infrequent occurrence of stunting, wasting, or underweight z-score values in this cohort are possible contributing factors to a lack of evidence for an association. Further research is needed to examine whether a threshold dose of aflatoxin exists that could induce child growth impairment.

  7. Rainbow Trout (Oncorhynchus mykiss) and Ultra-Low Dose Cancer Studies*

    PubMed Central

    Williams, David E.; Orner, Gayle; Willard, Kristin D.; Tilton, Susan; Hendricks, Jerry D.; Pereira, Clifford; Benninghoff, Abby D.; Bailey, George S.

    2010-01-01

    Cancer risk assessment utilizing rodents requires extrapolation across five orders of magnitude to estimate the Virtually Safe Dose (VSD). Regulatory agencies rely upon the Linear Extrapolated Dose (LED) except when sufficient information on mechanism of action justifies alternative models. Rainbow trout (Oncorhynchus mykiss) has been utilized at Oregon State University as a model for human cancer for forty years. Low cost and high capacity, made possible by our unique facility, along with low spontaneous background and high sensitivity, allow design and conduct of statistically challenging studies not possible in rodents. Utilization of custom microarrays demonstrates similarities in gene expression in trout and human hepatocellular carcinoma (HCC). We have completed one study employing over 42,000 trout with dibenzo[a,l]pyrene (DBP) and determined the dose resulting in 1 additional cancer in 5,000 animals, a 50-fold enhancement over the mouse ED01 study. Liver tumor incidence at low dose deviated significantly from linearity (concave down), whereas, DBP-DNA adductions deviated slightly (convex up). A second study is underway with aflatoxin B1 (AFB1). Results to date indicate AFB1 at low dose, in contrast to DBP, elicits a linear dose-response function on the log-log scale which falls below the LED with a slope slightly greater than 1.0. Such studies demonstrate the statistical power of the trout cancer model and strengthen the case for incorporation of these data-sets into risk assessment for these environmental human carcinogens. PMID:19135172

  8. Rainbow trout (Oncorhynchus mykiss) and ultra-low dose cancer studies.

    PubMed

    Williams, David E; Orner, Gayle; Willard, Kristin D; Tilton, Susan; Hendricks, Jerry D; Pereira, Clifford; Benninghoff, Abby D; Bailey, George S

    2009-03-01

    Cancer risk assessment utilizing rodents requires extrapolation across five orders of magnitude to estimate the Virtually Safe Dose (VSD). Regulatory agencies rely upon the Linear Extrapolated Dose (LED) except when sufficient information on mechanism of action justifies alternative models. Rainbow trout (Oncorhynchus mykiss) has been utilized at Oregon State University as a model for human cancer for forty years. Low cost and high capacity, made possible by our unique facility, along with low spontaneous background and high sensitivity, allow design and conduct of statistically challenging studies not possible in rodents. Utilization of custom microarrays demonstrates similarities in gene expression in trout and human hepatocellular carcinoma (HCC). We have completed one study employing over 42,000 trout with dibenzo[a,l]pyrene (DBP) and determined the dose resulting in 1 additional cancer in 5000 animals, a 50-fold enhancement over the mouse ED(01) study. Liver tumor incidence at low dose deviated significantly from linearity (concave down), whereas, DBP-DNA adductions deviated slightly (convex up). A second study is underway with aflatoxin B(1) (AFB(1)). Results to date indicate AFB(1) at low dose, in contrast to DBP, elicits a linear dose-response function on the log-log scale which falls below the LED with a slope slightly greater than 1.0. Such studies demonstrate the statistical power of the trout cancer model and strengthen the case for incorporation of these data-sets into risk assessment for these environmental human carcinogens.

  9. Rapid screening of aflatoxin B1 in beer by fluorescence polarization immunoassay.

    PubMed

    Beloglazova, N V; Eremin, S A

    2015-09-01

    This manuscript describes the development of a sensitive, fast and easily-performed fluorescence polarization immunoassay (FPIA) for the mycotoxin aflatoxin B1 (AFB1) in various beer samples, both lager and dark. The highest sensitivity was determined for six poly- and monoclonal antibodies selective towards aflatoxins. The sample pretreatment design was emphasized since beer samples are characterized by extremely diverse matrices. Herein, the choice of sorbent for effective removal of matrix interferences prior to analysis was crucial. The samples were diluted with a borate buffer solution containing 1% PEG 6000 and passed through the clean-up column packed with NH2-derivated silica. This sample pretreatment technique was perfectly suitable for the FPIA of lager beer samples, but for dark beer and ale it did not suffice. An artificial matrix was constructed to plot a calibration curve and quantify the results of the latter samples. The developed immunoassay was characterized by a limit of detection of 1 ng mL(-1). Apparent recovery values of 89-114% for lager and 80-125% for dark beer were established. The FPIA data for AFB1 was characterized by elevated linear regression coefficients, 0.9953 for spiked lager and 0.9895 for dark beer samples respectively.

  10. Effect of climate change on Aspergillus flavus and aflatoxin B1 production.

    PubMed

    Medina, Angel; Rodriguez, Alicia; Magan, Naresh

    2014-01-01

    This review considers the available information on the potential impact of key environmental factors and their interactions on the molecular ecology, growth and aflatoxin production by Aspergillus flavus in vitro and in maize grain. The recent studies which have been carried out to examine the impact of water activity × temperature on aflatoxin biosynthesis and phenotypic aflatoxin production are examined. These have shown that there is a direct relationship between the relative expression of key regulatory and structural genes under different environmental conditions which correlate directly with aflatoxin B1 production. A model has been developed to integrate the relative expression of 10 biosynthetic genes in the pathway, growth and aflatoxin B1 (AFB1) production which was validated under elevated temperature and water stress conditions. The effect of interacting conditions of aw × temperature × elevated CO2 (2 × and 3 × existing levels) are detailed for the first time. This suggests that while such interacting environmental conditions have little effect on growth they do have a significant impact on aflatoxin biosynthetic gene expression (structural aflD and regulatory aflR genes) and can significantly stimulate the production of AFB1. While the individual factors alone have an impact, it is the combined effect of these three abiotic factors which have an impact on mycotoxin production. This approach provides data which is necessary to help predict the real impacts of climate change on mycotoxigenic fungi.

  11. Antioxidant capacity and antimutagenic activity of natural oleoresin from greenhouse grown tomatoes (Lycopersicon esculentum).

    PubMed

    Rodríguez-Muñoz, Eustolia; Herrera-Ruiz, Gilberto; Pedraza-Aboytes, Gustavo; Loarca-Piña, Guadalupe

    2009-03-01

    Natural oleoresins rich in lycopene were obtained from two varieties of tomato (Zedona and Gironda) and their nutraceutical potential (antioxidant and antimutagenic capacity) was evaluated. Both oleoresins had a high content of lycopene, 58.33+/-1.67 mg/g (Zedona) and 63.97+/-0.80 mg/g (Gironda). The antioxidant activity (AA) of the oleoresins by beta-carotene method were 56.4-74.5% (Zedona) and 51-72.8% (Gironda), while when using the free radical stable 2,2-diphenyl-picryl-hydrazyl (DPPH) method, the antiradical activity (ARA) was determined to be 18.2-32.7% (Zedona) and 16.6-26.7% (Gironda) for the concentrations tested that of 200-400 microM equivalents of lycopene. The antimutagenic activity of the oleoresins was tested against aflatoxin B1 (AFB1) using the microsuspension assay, both varieties had a very high antimutagenic potential against AFB1 (60-66%).These results suggest the NCRT can be taken advantage to obtaining rich oleoresin in lycopene with a nutraceutical value.

  12. Bakery by-products based feeds borne-Saccharomyces cerevisiae strains with probiotic and antimycotoxin effects plus antibiotic resistance properties for use in animal production.

    PubMed

    Poloni, Valeria; Salvato, Lauranne; Pereyra, Carina; Oliveira, Aguida; Rosa, Carlos; Cavaglieri, Lilia; Keller, Kelly Moura

    2017-03-01

    The aim of this study was to select S. cerevisiae strains able to exert probiotic and antimycotoxin effects plus antibiotics resistance properties for use in animal production. S. cerevisiae LL74 and S. cerevisiae LL83 were isolated from bakery by-products intended for use in animal feed and examined for phenotypic characteristics and nutritional profile. Resistance to antibiotic, tolerance to gastrointestinal conditions, autoaggregation and coaggregation assay, antagonism to animal pathogens and aflatoxin B1 binding were studied. S. cerevisiae LL74 and S. cerevisiae LL83 showed resistance to all the antibiotics assayed (ampicillin, streptomycin, neomycin, norfloxacin, penicillin G, sulfonamide and trimethoprim). The analysis showed that exposure time to acid pH had a significant impact onto the viable cell counts onto both yeast strains. Presence of bile 0.5% increased significantly the growth of the both yeast strains. Moreover, they were able to tolerate the simulated gastrointestinal conditions assayed. In general, the coaggregation was positive whereas the autoaggregation capacity was not observed. Both strains were able to adsorb AFB1. In conclusion, selected S. cerevisiae LL74 and S. cerevisiae LL83 have potential application to be used as a biological method in animal feed as antibiotic therapy replacement in, reducing the adverse effects of AFB1 and giving probiotic properties.

  13. Single-compound and cumulative risk assessment of mycotoxins present in breakfast cereals consumed by children from Lisbon region, Portugal.

    PubMed

    Assunção, Ricardo; Vasco, Elsa; Nunes, Baltazar; Loureiro, Susana; Martins, Carla; Alvito, Paula

    2015-12-01

    Humans can be exposed to multiple chemicals, but current risk assessment is usually carried out on one chemical at a time. Mycotoxins are commonly found in a variety of foods including those intended to consumption by children namely breakfast cereals. The present study aims to perform, the risk assessment of single and multiple mycotoxins present in breakfast cereals consumed by children (1-3 years old) from Lisbon region, Portugal. Daily exposure of children to ochratoxin A, fumonisins and trichothecenes showed no health risks to the children population considering individual mycotoxins, while exposure to aflatoxin B1 (AFB1) suggested a potential health concern for the high percentiles of intake (P90, P95 and P99). The combined exposure to fumonisins and trichothecenes are not expected to be of health concern. The combined margin of exposure (MoET) for the aflatoxins group could constitute a potential health concern and AFB1 was the main contributor for MoET. Legal limits and control strategies regarding the presence of multiple mycotoxins in foodstuffs is an urgent need. To the best of our knowledge, this is the first time a cumulative risk assessment was performed on multiple mycotoxins present in breakfast cereals consumed by children.

  14. Alteration of p53 and p21 during hepatocarcinogenesis in tree shrews

    PubMed Central

    Su, Jian-Jia; Ban, Ke-Chen; Li, Yuan; Qin, Liu-Liang; Wang, Hui-Yun; Yang, Chun; Ou, Chao; Duan, Xiao-Xian; Lee, Young-Lk; Yang, Rui-Qi

    2004-01-01

    AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B1 (AFB1) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis. METHODS: Tree shrews were divided into four groups: group A, those infected with HBV and fed with AFB1 (n = 39); group B, those infected with HBV alone (n = 28); group C, those fed with AFB1 alone (n = 29); and group D, normal controls (n = 20). The tree shrews underwent liver biopsies once every 15 wk. Expression of p53 and p21 proteins and genes in the biopsies and tumor tissues of the experimental tree shrews was detected, respectively, by immunohistochemistry, and by Southern blotting and reverse transcription-polymerase chain reaction and sequencing. RESULTS: The incidence of hepatocellular carcinomas (HCC) was higher in group A (66.7%) than that in group B (3.57%) and C (30%). The time of HCC occurrence was also earlier in group A than that in group C (120.0 ± 16.6 wk vs 153.3 ± 5.8 wk, respectively, P < 0.01). p53 protein was not detected by immunohistochemistry in all groups before the 75th wk of the experiment. At the 105th wk, the positive rates fo p53 were 78.6%, 60% and 71.4% in groups A, B and C, respectively, which were significantly higher than that in group D (10%) (all P < 0.05). An abnormal band of p53 gene was observed in groups A and C. The mutation points of p53 gene in tree shrews with HCC were at codons 275, 78 and 13. The nucleotide sequence and amino acid sequence of tree shrew’s wild-type p53 showed 91.7% and 93.4% homologies with those of human p53, respectively. The immunopositivity for p21 was found before HCC development. The incidence of HCC was significantly higher in tree shrews that were positive for p21 than those negative for p21 (80.0% vs 11.0%, P < 0.001). The incidence of HCC in p21 positive animals in group A was significantly higher than those positive for p21 in group C (P < 0.05). CONCLUSION: A remarkable

  15. Inhibitory Effect of Cinnamaldehyde, Citral, and Eugenol on Aflatoxin Biosynthetic Gene Expression and Aflatoxin B1 Biosynthesis in Aspergillus flavus.

    PubMed

    Liang, Dandan; Xing, Fuguo; Selvaraj, Jonathan Nimal; Liu, Xiao; Wang, Limin; Hua, Huijuan; Zhou, Lu; Zhao, Yueju; Wang, Yan; Liu, Yang

    2015-12-01

    In order to reveal the inhibitory effects of cinnamaldehyde, citral, and eugenol on aflatoxin biosynthesis, the expression levels of 5 key aflatoxin biosynthetic genes were evaluated by real-time PCR. Aspergillus flavus growth and AFB1 production were completely inhibited by 0.80 mmol/L of cinnamaldehyde and 2.80 mmol/L of citral. However, at lower concentration, cinnamaldehyde (0.40 mmol/L), eugenol (0.80 mmol/L), and citral (0.56 mmol/L) significantly reduced AFB1 production with inhibition rate of 68.9%, 95.4%, and 41.8%, respectively, while no effect on fungal growth. Real-time PCR showed that the expressions of aflR, aflT, aflD, aflM, and aflP were down-regulated by cinnamaldehyde (0.40 mmol/L), eugenol (0.80 mmol/L), and citral (0.56 mmol/L). In the presence of cinnamaldehyde, AflM was highly down-regulated (average of 5963 folds), followed by aflP, aflR, aflD, and aflT with the average folds of 55, 18, 6.5, and 5.8, respectively. With 0.80 mmol/L of eugenol, aflP was highly down-regulated (average of 2061-folds), followed by aflM, aflR, aflD, and aflT with average of 138-, 15-, 5.2-, and 4.8-folds reduction, respectively. With 0.56 mmol/L of citral, aflT was completely inhibited, followed by aflM, aflP, aflR, and aflD with average of 257-, 29-, 3.5-, and 2.5-folds reduction, respectively. These results suggest that the reduction in AFB1 production by cinnamaldehyde, eugenol, and citral at low concentration may be due to the down-regulations of the transcription level of aflatoxin biosynthetic genes. Cinnamaldehyde and eugenol may be employed successfully as a good candidate in controlling of toxigenic fungi and subsequently contamination with aflatoxins in practice.

  16. Differential expression of genes during aflatoxin B1-induced hepatocarcinogenesis in tree shrews

    PubMed Central

    Li, Yuan; Wan, Da-Fang; Su, Jian-Jia; Cao, Ji; Ou, Chao; Qiu, Xiao-Kun; Ban, Ke-Chen; Yang, Chun; Qin, Liu-Liang; Luo, Dan; Yue, Hui-Fen; Zhang, Li-Sheng; Gu, Jian-Ren

    2004-01-01

    AIM: Through exploring the regulation of gene expression during hepatocarcinogenesis induced by aflatoxin B1 (AFB1), to find out the responsible genes for hepatocellular carcinoma (HCC) and to further understand the underlying molecular mechanism. METHODS: Tree shrews (Tupaia belangeri chinensis) were treated with or without AFB1 for about 90 weeks. Liver biopsies were performed regularly during the animal experiment. Eight shares of total RNA were respectively isolated from 2 HCC tissues, 2 HCC-surrounding non-cancerous liver tissues, 2 biopsied tissues at the early stage (30th week) of the experiment from the same animals as above, 1 mixed sample of three liver tissues biopsied at the beginning (0th week) of the experiment, and another 1 mixed sample of two liver tissues from the untreated control animals biopsied at the 90th week of the experiment. The samples were then tested with the method of AtlasTM cDNA microarray assay. The levels of gene expression in these tissues taken at different time points during hepatocarcinogenesis were compared. RESULTS: The profiles of differently expressed genes were quite different in different ways of comparison. At the same period of hepatocarcinogenesis, the genes in the same function group usually had the same tendency for up- or down-regulation. Among the checked 588 genes that were known to be related to human cancer, 89 genes (15.1%) were recognized as “important genes” because they showed frequent changes in different ways of comparison. The differentially expressed genes during hepatocarcinogenesis could be classified into four categories: genes up-regulated in HCC tissue, genes with similar expressing levels in both HCC and HCC-surrounding liver tissues which were higher than that in the tissues prior to the development of HCC, genes down-regulated in HCC tissue, and genes up-regulated prior to the development of HCC but down-regulated after the development of HCC. CONCLUSION: A considerable number of genes could

  17. Testing an aflatoxin B1 gene signature in rat archival tissues.

    PubMed

    Merrick, B Alex; Auerbach, Scott S; Stockton, Patricia S; Foley, Julie F; Malarkey, David E; Sills, Robert C; Irwin, Richard D; Tice, Raymond R

    2012-05-21

    Archival tissues from laboratory studies represent a unique opportunity to explore the relationship between genomic changes and agent-induced disease. In this study, we evaluated the applicability of qPCR for detecting genomic changes in formalin-fixed, paraffin-embedded (FFPE) tissues by determining if a subset of 14 genes from a 90-gene signature derived from microarray data and associated with eventual tumor development could be detected in archival liver, kidney, and lung of rats exposed to aflatoxin B1 (AFB1) for 90 days in feed at 1 ppm. These tissues originated from the same rats used in the microarray study. The 14 genes evaluated were Adam8, Cdh13, Ddit4l, Mybl2, Akr7a3, Akr7a2, Fhit, Wwox, Abcb1b, Abcc3, Cxcl1, Gsta5, Grin2c, and the C8orf46 homologue. The qPCR FFPE liver results were compared to the original liver microarray data and to qPCR results using RNA from fresh frozen liver. Archival liver paraffin blocks yielded 30 to 50 μg of degraded RNA that ranged in size from 0.1 to 4 kB. qPCR results from FFPE and fresh frozen liver samples were positively correlated (p ≤ 0.05) by regression analysis and showed good agreement in direction and proportion of change with microarray data for 11 of 14 genes. All 14 transcripts could be amplified from FFPE kidney RNA except the glutamate receptor gene Grin2c; however, only Abcb1b was significantly upregulated from control. Abundant constitutive transcripts, S18 and β-actin, could be amplified from lung FFPE samples, but the narrow RNA size range (25-500 bp length) prevented consistent detection of target transcripts. Overall, a discrete gene signature derived from prior transcript profiling and representing cell cycle progression, DNA damage response, and xenosensor and detoxication pathways was successfully applied to archival liver and kidney by qPCR and indicated that gene expression changes in response to subchronic AFB1 exposure occurred predominantly in the liver, the primary target for AFB1-induced

  18. Multiplex surface plasmon resonance biosensing and its transferability towards imaging nanoplasmonics for detection of mycotoxins in barley.

    PubMed

    Joshi, Sweccha; Segarra-Fas, Anna; Peters, Jeroen; Zuilhof, Han; van Beek, Teris A; Nielen, Michel W F

    2016-02-21

    A 6-plex competitive inhibition immunoassay for mycotoxins in barley was developed on a prototype portable nanostructured imaging surface plasmon resonance (iSPR) instrument, also referred to as imaging nanoplasmonics. As a benchmark for the prototype nanoplasmonics instrument, first a double 3-plex assay was developed for the detection of deoxynivalenol (DON), zearalenone (ZEA), T-2 toxin (T-2), ochratoxin A (OTA), fumonisin B1 (FB1) and aflatoxin B1 (AFB1) using a well-established benchtop SPR instrument and two biosensor chips. To this end, ovalbumin (OVA) conjugates of mycotoxins were immobilized on the chip via amine coupling. The SPR response was then recorded upon injection of a mixture of antibodies at a fixed concentration and the sample (or matrix-matched standard) over a chip with immobilized mycotoxin-OVA conjugates. The chips were regenerated after each sample using 10 mM HCl and 20 mM NaOH and could be used for at least 60 cycles. The limits of detection in barley (in μg kg(-1)) were determined to be 26 for DON, 6 for ZEA, 0.6 for T-2, 3 for OTA, 2 for FB1 and 0.6 for AFB1. Preliminary in-house validation showed that DON, T-2, ZEA and FB1 can be detected at the European Union regulatory limits, while for OTA and AFB1 sensitivities should be improved. Furthermore, measurement of naturally contaminated barley showed that the assay can be used as a semi-quantitative screening method for mycotoxins prior to liquid chromatography tandem mass spectrometry (LC-MS/MS). Finally, using the same bio-reagents the assay was transferred to a 6-plex format in the nanoplasmonics instrument and subsequently the two assays were compared. Although less sensitive, the 6-plex portable iSPR assay still allowed detection of DON, T-2, ZEA and FB1 at relevant levels. Therefore, the prototype iSPR shows potential for future applications in rapid in-field and at-line screening of multiple mycotoxins.

  19. Development and validation of a liquid chromatography/atmospheric pressure photoionization-tandem mass spectrometric method for the analysis of mycotoxins subjected to commission regulation (EC) No. 1881/2006 in cereals.

    PubMed

    Capriotti, Anna Laura; Foglia, Patrizia; Gubbiotti, Riccardo; Roccia, Claudia; Samperi, Roberto; Laganà, Aldo

    2010-09-24

    A sensitive and reliable liquid chromatography/photoionization (APPI) tandem mass spectrometry method has been developed for determining nine selected mycotoxins in wheat and maize samples. The analytes were chosen on the basis of the mycotoxins under EU Commission Regulation (EC) No. 1881/2006, i.e., deoxynivalenol (DON), zearalenone (ZON), aflatoxins (AFs), and ochratoxin A (OTA), and considering the possibility of a near future regulation for T-2 and HT-2 toxins. Mycotoxins were extracted from samples by means of an one-step solvent extraction without any cleanup. The developed multi-mycotoxin method permits simultaneous, simple, and rapid determination of several co-existing toxins separated in a single chromatographic run, in which AFs, T-2 and HT-2 toxin are acquired in positive, while OTA, DON and ZON in negative mode. Although a moderate signal suppression was noticeable, matrix effect did not give significant differences at p=0.05. Then, calibration in standard solution were used for quantitation. Based on the EU Commission Decision 2002/657/EC, the method was in-house validated in terms of ruggedness, specificity, linearity, trueness, within-laboratory reproducibility, decision limit (CCalpha) and detection capability (CCbeta). For all the analytes, the regression coefficient r ranged between 0.8752 (DON in wheat) and 0.9465 (ZON in maize), biases related to mean concentrations were from -13% to +12% of the nominal spiking level, and the overall within-laboratory reproducibility ranged 3-16%; finally, CCalpha values did not differ more than 20% and CCbeta not more than 42% from their respective maximum limit. Method quantification limits ranged from 1/20 (AFG1) to 1/4 (AFG2 and OTA) the maximum limit established by European Union in the Commission Regulation (EC) No. 1881/2006 and its subsequent amendments.

  20. Assessment of isorhamnetin 3-O-neohesperidoside from Acacia salicina: protective effects toward oxidation damage and genotoxicity induced by aflatoxin B1 and nifuroxazide.

    PubMed

    Bouhlel, Ines; Limem, Ilef; Skandrani, Ines; Nefatti, Aicha; Ghedira, Kamel; Dijoux-Franca, Marie-Genevieve; Leila, Chekir-Ghedira

    2010-08-01

    Antioxidant activity of isorhamnetin 3-O-neohesperidoside, isolated from the leaves of Acacia salicina, was determined by the ability of this compound to inhibit xanthine oxidase activity and to scavenge the free radical 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS(.-)) diammonium salt. Antigenotoxic activity was assessed using the SOS chromotest assay. This compound has the ability to scavenge the ABTS(.+) radical by a hydrogen donating mechanism. We also envisaged the study of the antioxidant effect of this compound by the enzymatic xanthine/xanthine oxidase (X/XOD) assay. Results indicated that isorhamnetin 3-O-neohesperidoside was a potent inhibitor of xanthine oxidase and superoxide anion scavengers. Moreover, this compound induced an inhibitory activity against nifuroxazide and aflatoxine B1 (AFB1) induced genotoxicity. Taken together, these observations provide evidence that isorhamnetin 3-O-neohesperidoside isolated from the leaves of A. salicina is able to protect cells against the consequences of oxidative stress.

  1. An enzyme-free catalytic DNA circuit for amplified detection of aflatoxin B1 using gold nanoparticles as colorimetric indicators

    NASA Astrophysics Data System (ADS)

    Chen, Junhua; Wen, Junlin; Zhuang, Li; Zhou, Shungui

    2016-05-01

    An enzyme-free biosensor for the amplified detection of aflatoxin B1 has been constructed based on a catalytic DNA circuit. Three biotinylated hairpin DNA probes (H1, H2, and H3) were designed as the assembly components to construct the sensing system (triplex H1-H2-H3 product). Cascaded signal amplification capability was obtained through toehold-mediated strand displacement reactions to open the hairpins and recycle the trigger DNA. By the use of streptavidin-functionalized gold nanoparticles as the signal indicators, the colorimetric readout can be observed by the naked eye. In the presence of a target, the individual nanoparticles (red) aggregate into a cross-linked network of nanoparticles (blue) via biotin-streptavidin coupling. The colorimetric assay is ultrasensitive, enabling the visual detection of trace levels of aflatoxin B1 (AFB1) as low as 10 pM without instrumentation. The calculated limit of detection (LOD) is 2 pM in terms of 3 times standard deviation over the blank response. The sensor is robust and works even when challenged with complex sample matrices such as rice samples. Our sensing platform is simple and convenient in operation, requiring only the mixing of several solutions at room temperature to achieve visible and intuitive results, and holds great promise for the point-of-use monitoring of AFB1 in environmental and food samples.An enzyme-free biosensor for the amplified detection of aflatoxin B1 has been constructed based on a catalytic DNA circuit. Three biotinylated hairpin DNA probes (H1, H2, and H3) were designed as the assembly components to construct the sensing system (triplex H1-H2-H3 product). Cascaded signal amplification capability was obtained through toehold-mediated strand displacement reactions to open the hairpins and recycle the trigger DNA. By the use of streptavidin-functionalized gold nanoparticles as the signal indicators, the colorimetric readout can be observed by the naked eye. In the presence of a target, the

  2. Reduction in the urinary aflatoxin M1 biomarker as an early indicator of the efficacy of dietary interventions to reduce exposure to aflatoxins.

    PubMed

    Mitchell, Nicole J; Kumi, Justice; Johnson, Natalie M; Dotse, Eunice; Marroquin-Cardona, Alicia; Wang, Jia-Sheng; Jolly, Pauline E; Ankrah, Nii-Ayi; Phillips, Timothy D

    2013-08-01

    Aflatoxin B1 is a persistent public health issue in Ghana. Assessment of AFB1 intervention efficacy is currently dependent on long-term biomarkers. This study was designed to determine whether daily AFM1 biomarker levels could be utilized as an early detection method for intervention efficacy. Participants were treated with a refined calcium montmorillonite clay (UPSN) or a placebo (calcium carbonate) in a crossover study. Urine samples were assessed for AFM1 levels daily. UPSN treatment reduced AFM1 biomarkers by 55% compared to the placebo. This is the first study to show that daily urinary AFM1 levels can be used as a biomarker of internal aflatoxin B1 exposure in short-term intervention trials to determine efficacy.

  3. Antimutagenicity and Antiproliferative Studies of Lipidic Extracts from White Shrimp (Litopenaeus vannamei)

    PubMed Central

    Wilson-Sanchez, Griselda; Moreno-Félix, Carolina; Velazquez, Carlos; Plascencia-Jatomea, Maribel; Acosta, Anita; Machi-Lara, Lorena; Aldana-Madrid, María-Lourdes; Ezquerra-Brauer, Josafat-Marina; Robles-Zepeda, Ramón; Burgos-Hernandez, Armando

    2010-01-01

    An organic extract from fresh shrimp (Litopenaeus vannamei) was studied for antimutagenic and antiproliferative properties using Salmonella typhimurium tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. Shrimp extract was sequentially fractionated by thin layer chromatography (TLC) and each fraction was tested for antimutagenic and antiproliferative activities. Crude organic extracts obtained from shrimp reduced the number of revertants caused by aflatoxina B1, showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. These results suggested that the lipid fraction of the tested species contained compounds with chemoprotective properties that reduce the mutagenicity of AFB1 and proliferation of a cancer cell line. PMID:21139845

  4. Bioactive Lipidic Extracts from Octopus (Paraoctopus limaculatus): Antimutagenicity and Antiproliferative Studies

    PubMed Central

    Moreno-Félix, Carolina; Wilson-Sánchez, Griselda; Cruz-Ramírez, Susana-Gabriela; Velázquez-Contreras, Carlos; Plascencia-Jatomea, Maribel; Acosta, Ana; Machi-Lara, Lorena; Aldana-Madrid, María-Lourdes; Ezquerra-Brauer, Josafat-Marina; Rocha-Alonzo, Fernando; Burgos-Hernández, Armando

    2013-01-01

    Fractions from an organic extract from fresh octopus (Paraoctopus limaculatus) were studied for biological activities such as antimutagenic and antiproliferative properties using Salmonella tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. A chloroform extract obtained from octopus tentacles was sequentially fractionated using thin layer chromatography (TLC), and each fraction was tested for antimutagenic and antiproliferative activities. Organic extract reduced the number of revertants caused by aflatoxin B1 showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. Based on the results obtained, the isolated fractions obtained from octopus contain compounds with chemoprotective properties that reduce the mutagenicity of AFB1 and proliferation of cancer cell lines. PMID:23401709

  5. Antimutagenic and antioxidant potentials of Teucrium ramosissimum essential oil.

    PubMed

    Sghaier, Mohamed Ben; Boubaker, Jihed; Neffati, Aicha; Limem, Ilef; Skandrani, Ines; Bhouri, Wissem; Bouhlel, Ines; Kilani, Soumaya; Chekir-Ghedira, Leila; Ghedira, Kamel

    2010-07-01

    The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4-nitro-o-phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro-blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical-scavenging activity was observed towards DPPH(.) and O2(.-). In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay.

  6. Aflatoxins in various food from Istanbul, Turkey.

    PubMed

    Hacıbekiroğlu, I; Kolak, U

    2013-01-01

    The present work reports the total aflatoxin and aflatoxin B1 levels in 62 food samples from Istanbul, Turkey. The total aflatoxin content in dried American cucumber, squash, tomato, okra and saffron samples was found to be 1.7 μg/kg. AFB1 levels in five dried vegetables (red bell pepper, American cucumber, squash, tomato and okra), two tea (linden and jasmine flower) and three spice samples (cardamom, galangal and saffron) were 1 μg/kg. Of the tested samples, 76% exceeded legal limits of total aflatoxin. The highest levels were determined in chestnut (232.9 μg/kg), nutmeg (206.1 μg/kg) and sumac (182.5 μg/kg). These findings confirm the existing knowledge that food should be regularly and effectively controlled.

  7. Aflatoxin B1, zearalenone and deoxynivalenol production on irradiated corn kernels: Influence of inoculum size.

    PubMed

    Magnoli, C; Etcheverry, M G; Cavaglieri, L; Saenz, M; Alvarez, G; Lecumberry, S

    1998-03-01

    The influence of inoculum size on aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) production was examined on irradiated corn kernels.Spore concentrations were determined in serial dilutions and adjusted to 10,10(2),10(3),10(5) and 10(6) spores/ml. Aflatoxin B1 production was dependent on the inoculum size. The high levels of aflatoxin B1 produced byA. parasiticus (21 and 30 mg/kg) were obtained with 10(2) and 10(3) spores/ml after 35 and 20 days incubation. There was no spore concentration influence on zearalenone and deoxynivalenol production after 10, 20 and 35 days incubation. At 28°C and 0.97 water activity (aw), the mean levels of zearalenone production were 382, 267 and 520 µg/kg and the mean levels on deoxynivalenol production were 697,465 and 782 µg/kg.

  8. Optical waveguide lightmode spectroscopy technique-based immunosensor development for aflatoxin B1 determination in spice paprika samples.

    PubMed

    Majer-Baranyi, Krisztina; Zalán, Zsolt; Mörtl, Mária; Juracsek, Judit; Szendrő, István; Székács, András; Adányi, Nóra

    2016-11-15

    Optical waveguide lightmode spectroscopy (OWLS) technique has been applied to label-free detection of aflatoxin B1 in a competitive immunoassay format, with the aim to compare the analytical goodness of the developed OWLS immunosenor with HPLC and enzyme-linked immunosorbent assay (ELISA) methods for the detection of aflatoxin in spice paprika matrix. We have also assessed applicability of the QuEChERS method prior to ELISA measurements, and the results were compared to those obtained by traditional solvent extraction followed by immunoaffinity clean-up. The AFB1 content of sixty commercial spice paprika samples from different countries were measured with the developed and optimized OWLS immunosensor. Comparing the results from the indirect immunosensor to that obtained by HPLC or ELISA provided excellent correlation (with regression coefficients above 0.94) indicating that the competitive OWLS immunosensor has a potential for quick determination of aflatoxin B1 in paprika samples.

  9. Modified Nanodiamonds for Detoxification

    NASA Astrophysics Data System (ADS)

    Gibson, Natalie Marie

    Nanodiamonds (NDs) are an emerging class of biomaterials that are reaching worldwide attention due to their biocompatible, nontoxic properties and abundant surface chemistries that lend them to a wide range of biomedical applications. Furthermore, surface functional groups of NDs can easily be tailored to exhibit desirable chemical, physical and biological properties. Such characteristics naturally allow for NDs' surface to be considered as ideal carriers for various molecules and biomolecules intended for the delivery or removal of molecules in vivo. NDs have already shown to have a high affinity for various biological molecules, including DNA and proteins. This dissertation, however, expands NDs' use to the adsorption of carcinogenic mycotoxins, aflatoxin B1 (AfB1) and ochratoxin A (OTA). It has been estimated that myocotoxins are found in approximately 25 % of the world's crops each year. Ingestion of mycotoxins contaminated crops has been linked to hepatocellular carcinoma, disease and death. Therefore, we aim to develop ND enterosorbents, for the binding and removal of mycotoxins within the gastrointestinal (GI) tract, thereby eliminating the effects of these toxins. While NDs are readily available, raw, unmodified NDs, like those typically received from vendors, possess inhomogeneous aggregate sizes and surface characteristics. Our research first explored several ND modification techniques to enhance ND's adsorption of AfB1 and OTA. Modification methods assessed in this research include size reduction techniques, plasma treatments, silane surface coatings and homogenous surface group termination, including carboxylation, hydrogenation and hydroxylation. The effectiveness of these NDs for mycotoxins removal was determined by calculations of maximum capacities and binding constants, as obtained through the Langmuir isotherm and related transform equations. Several of these treatments also showed heightening of the NDs' inherent zeta potentials (ZPs), which were essential for interacting with charged molecules, like OTA. Furthermore, the increased ZPs lead to improved colloidal stabilities over a wide range of pH, which is important for their interaction in the GI tract. While the dyes and OTA illustrated primarily electrostatic adsorption mechanisms, neutrally charged AfB1's adsorption was predominantly based upon the aggregate size of the ND substrate. In addition to mycotoxins, fluorescent dyes, including propidium iodide, pyranine and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), were initially utilized during methodological development. Fluorescent dye investigations helped assesses the adsorption mechanisms of NDs and demonstrated the significance of electrostatic interactions. Beyond electrostatic adsorption mechanisms, surface functional groups were also responsible for the amount of dye adsorbed, as was also true in OTA adsorption. Therefore, surface characterization was carried out for several ND samples by FTIR, TOF-SIMS and TDMS analysis. Final results of our studies show that our modified NDs perform better than yeast cells walls and other NDs but comparable to activated charcoal in the adsorption of AfB1, and outperform clay minerals in OTA studies. Moreover, it was demonstrated that adsorption can be maintained in a wide range of pH, thereby, increasing the possibility of NDs use in mycotoxins enterosorbent applications.

  10. miR319, miR390, and miR393 Are Involved in Aluminum Response in Flax (Linum usitatissimum L.)

    PubMed Central

    Zyablitsin, Alexander V.; Rozhmina, Tatiana A.; Speranskaya, Anna S.; Sadritdinova, Asiya F.

    2017-01-01

    Acid soils limit agricultural production worldwide. Major reason of crop losses in acid soils is the toxicity of aluminum (Al). In the present work, we investigated expression alterations of microRNAs in flax (Linum usitatissimum L.) plants under Al stress. Flax seedlings of resistant (TMP1919 and G1071/4_k) and sensitive (Lira and G1071/4_o) to Al cultivars and lines were exposed to AlCl3 solution for 4 and 24 hours. Twelve small RNA libraries were constructed and sequenced using Illumina platform. In total, 97 microRNAs from 18 conserved families were identified. miR319, miR390, and miR393 revealed expression alterations associated with Al treatment of flax plants. Moreover, for miR390 and miR393, the alterations were distinct in sensitive and resistant to Al genotypes. Expression level changes of miR319 and miR390 were confirmed using qPCR analysis. In flax, potential targets of miR319 are TCPs, miR390–TAS3 and GRF5, and miR393–AFB2-coding transcripts. TCPs, TAS3, GRF5, and AFB2 participate in regulation of plant growth and development. The involvement of miR319, miR390, and miR393 in response to Al stress in flax was shown here for the first time. We speculate that these microRNAs play an important role in Al response via regulation of growth processes in flax plants. PMID:28299328

  11. Investigation of biological activity of polar extracts isolated from Phlomis crinita Cav ssp. mauritanica Munby.

    PubMed

    Limem-Ben Amor, Ilef; Skandrani, Ines; Boubaker, Jihed; Ben Sghaïer, Mohamed; Neffati, Aicha; Bhouri, Wissem; Bouhlel, Ines; Chouchane, Nabil; Kilani, Soumaya; Guedon, Emmanuel; Ghoul, Mohamed; Ghedira, Kamel; Chekir-Ghedira, Leila

    2009-01-01

    The lyophilized infusion, the methanol, the ethyl acetate, and the total oligomer flavonoid (TOF)-enriched extracts prepared from the dried leaves of Phlomis crinita Cav. ssp. mauritanica Munby were investi