Terahertz metamaterial biosensors have attracted significant attention in the biological field due to their advantages of label-free,real-time and in situ detection.In this paper,a highly sensitive metamaterial sensor...Terahertz metamaterial biosensors have attracted significant attention in the biological field due to their advantages of label-free,real-time and in situ detection.In this paper,a highly sensitive metamaterial sensor with semi-ring mirror symmetry based on toroidal dipole resonance is designed for a new metamaterial biosensor.It is shown that a refractive index sensitivity of 337.5 GHz per refractive index unit can be achieved under an analyte of saturated thickness near a 1.33 THz transmission dip.For biosensor samples where aflatoxin B1 is dropped on the metamaterial surface in our experiment,dip amplitudes of transmission varying from 0.1904 to 0.203 and 0.2093 are observed as aflatoxin B1 concentrations are altered from 0 to 0.001μg·ml-1 and to 0.01μg·ml-1,respectively.Furthermore,when aflatoxin B1 concentrations are 0.1μg·ml-1,1μg·ml-1,10μg·ml-1 and 100μg·ml-1,dip amplitudes of 0.2179,0.226,0.2384 and 0.2527 and dip redshifts of 10.1 GHz,20.1 GHz,27.7 GHz and 37.6 GHz are respectively observed.These results illustrate high-sensitivity,label-free detection of aflatoxin B1,enriching the applications of sensors in the terahertz domain.展开更多
San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seri...San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seriously reduces the carcass quality and economic benefit of yellow-feathered broilers. In this study, the cause of this abnormal green skin in shank was systematically investigated. Physiological anatomy revealed that the abnormal skin in shank was primarily due to the deposition of melanin under the dermis. After analyzing multiple potential causes such as heredity(pedigree and genetic markers), environment(water quality monitoring) and feed composition(mycotoxin detection), excessive aflatoxin B1(AFB1) in feed was screened, accompanied with a higher L-dihydroxy-phenylalanine(L-DOPA)(P<0.05) and melanin content(P<0.01). So it was speculated that excessive AFB1 might be the main cause of abnormal green skin in shank. Subsequently, the further results showed that a high concentration of AFB1(>170 μg kg–1)indeed induced the abnormal green skin in shank compared to the normal AFB1 content(<10 μg kg–1), and the mRNA levels of TYR, TYRP1, MITE, MC1R and EDN3 genes related to melanin deposition would significantly up-regulate(P<0.01) and the content and activity of tyrosinase(TyR) significantly increased(P<0.05). At the same time, the content of L-DOPA and melanin deposition also increased significantly(P<0.01), which also confirmed the effect of excessive AFB1 on melanin deposition in skin of shank. Results of additional experiments revealed that the AFB1's negative effect on melanin deposition in skin of shank could last for a longer time. Taken together, the results of this study explained the occurrence and possible mechanisms of the abnormal AFB1-related green skin in shank of chickens. Excessive AFB1 in diets increased the L-DOPA content and melanin abnormal deposition in the chicken shank possibly via promoting TyR content and activity, and the expression of melanin synthesis-related genes. Furthermore, our findings once again raised the alarm of the danger of AFB1 in the broiler production.展开更多
Aflatoxin contamination of crops is frequent in warm regions across the globe, including large areas in sub-Saharan Africa and Burkina Faso. A?atoxins and fumonisins are among the mycotoxins that have been increasingl...Aflatoxin contamination of crops is frequent in warm regions across the globe, including large areas in sub-Saharan Africa and Burkina Faso. A?atoxins and fumonisins are among the mycotoxins that have been increasingly reported to affect health and productivity of livestock globally. It cuts across the value chain, affecting farmers, markets, and finally consumers. However, a?atoxin contamination is a threatening issue in these staples and its negative effects on human health, most especially on infants and young children, are very alarming. Among the cereals in Burkina Faso, the maize is more vulnerable to contamination by Aspergillus sp. The contamination of maize by the aflatoxin is the main cause affecting production of agricultural sector, food security and regularity. Many factors are responsible for its proliferating. Therefore aflatoxins reduction in cereals such as maize is a serious concern for quality and safety. This review aimed to highlight the factors influencing a?atoxins contamination, and methods of reduction.展开更多
Aflatoxins are toxic metabolites present in various foods, especially when production and conservation do not respect good hygiene practices (GHP). In Ouagadougou, maize flour is produced and sold in different structu...Aflatoxins are toxic metabolites present in various foods, especially when production and conservation do not respect good hygiene practices (GHP). In Ouagadougou, maize flour is produced and sold in different structures by actors who do not always respect GHP. Thus, it is necessary to regularly control the quality of these flours. So, this is carried out with the aim to assess the aflatoxin content of maize flours produced in the municipality of Ouagadougou. For this, twenty-eight (28) samples were collected from households, markets and supermarkets in the city of Ouagadougou. Thus, LC/MS/MS analysis was used to assess the aflatoxin content of the samples. The results obtained reveal the presence of total aflatoxins (AFT) in 78.57% of samples analyzed with levels ranging from 0.89 to 64.25 μg/kg. The prevalence of different types of aflatoxins were 57.14% for aflatoxin B1 (AFB1), 46.43% for aflatoxin B2 (AFB2), 42.86% for aflatoxin G1 (AFG1) and 4.6% for aflatoxin G2 (AFG2). The results also show that 80% and 60% of market samples, 70% and 30% of household samples and 37.5% and 25% of supermarket samples do not comply with European Commission standards for AFT and AFB1 respectively. For all the samples, 60.71% and 42.86% of the samples are compliant according to the limits established by the European Commission (EC) respectively for AFB1 and AFT. Regarding the results obtained, producers and processors must be supervised and trained in GHP for the production of better-quality flours.展开更多
Method validation for quantitative analysis of aflatoxins, AFB1, AFB2, AFG1 and AFG2 in sorghum, peanut butter, groundnut and animals feed is presented. Aflatoxins were extracted with a mixture of methanol: acetonitri...Method validation for quantitative analysis of aflatoxins, AFB1, AFB2, AFG1 and AFG2 in sorghum, peanut butter, groundnut and animals feed is presented. Aflatoxins were extracted with a mixture of methanol: acetonitrile: water (60:30:10) and cleaned with Alfa test IAC chromatography before analysis by High Performance Liquid Chromatography coupled with fluorescence detection (HPLC-FLD) by adopting an isocratic chromatographic system using a mobile phase consisting acetic acid: acetonitrile: methanol (59:14:27), the separation of the four aflatoxins was achieved in less than 15 minutes. Calibration curves were linear over the concentration range from 2 - 18 ng/mL for AFB1 and AFG1, 0.4 - 3.6 ng/mL for AFB2 and AFG2, respectively. The LOD and LOQ in spiked samples were found to be 0.02 and 0.05 μg/kg for both AFB1 and AFG1, 0.01 and 0.03 μg/kg for both AFB2 and AFG2. The mean recovery values were in range from 84.2% to 96.9% was obtained. Five samples were found to be contaminated with aflatoxins and the total aflatoxins ranged from 0.02 to 3.26 μg/kg were obtained. Nineteen different samples were found to be contaminated with aflatoxins;the total aflatoxins ranged from 0.27 to 10.48 μg/kg were obtained. The highest total aflatoxins value was obtained in animal feeds.展开更多
Busia and Kisii Central districts are areas in western Kenya that have repeatedly reported high levels of stunting growth in children and an increase in hepatocellular carcinoma (HCC);an aspect often positively associ...Busia and Kisii Central districts are areas in western Kenya that have repeatedly reported high levels of stunting growth in children and an increase in hepatocellular carcinoma (HCC);an aspect often positively associated with chronic exposure to aflatoxins especially through consumption of foods such as peanuts. The objectives of the study were to determine the incidence, types and levels of aflatoxin in different varieties of peanuts produced in Busia and Kisii Central districts. One hundred and two (102) peanuts samples were collected from farmers’ in each district. Aflatoxin types and levels of aflatoxins were analyzed using high performance liquid chromatography (HPLC) technique. All the peanuts samples from Kisii Central and 97.06% samples from Busia were contaminated with aflatoxins. However, aflatoxin was not detected in 2.94% of samples from Busia district. The levels of total aflatoxin ranges were 0.1 to 268 μg/kg and 1.63 to 591.1 μg/kg in peanuts from Busia and Kisii Central respectively. Majority of peanuts samples had levels within Kenya Bureau of Standards (KEBS) and European Union (EU) regulatory limits for total aflatoxins. Improved variety (Valencia red) had significantly lower aflatoxin contamination compared to local varieties (Uganda local red, Homabay local and Local red). Aflatoxins B1, B2, G1 and G2 were found in peanuts;B1 was the most predominant in both districts (t = 12.4, df = 3, P = 0.034). The levels of aflatoxins especially in peanuts from Kisii Central district were high (591.1 μg/kg) where 44.6% of samples analyzed were unfit for even animal feed (USFDA regulatory limit). An assessment on the levels of aflatoxins should be done by the relevant stakeholders in other key foods in the areas for example maize. The most lethal aflatoxin type B1 was found to be the most predominant peanuts from both districts of study. This calls for frequent aflatoxin screening of peanuts from the districts particularly aflatoxin type B.展开更多
Hepatocellular carcinoma(HCC) is one of the leading causes of cancer deaths worldwide,primarily affecting populations in the developing countries.Aflatoxin,a food contaminant produced by the fungi Aspergillus flavus a...Hepatocellular carcinoma(HCC) is one of the leading causes of cancer deaths worldwide,primarily affecting populations in the developing countries.Aflatoxin,a food contaminant produced by the fungi Aspergillus flavus and Aspergillus parasiticus,is a known human carcinogen that has been shown to be a causative agent in the pathogenesis of HCC.Aflatoxin can affect a wide range of food commodities including corns,oilseeds,spices,and tree nuts as well as milk,meat,and dried fruit.Many factors affect the growth of Aspergillus fungi and the level of aflatoxin contamination in food.Drought stress is one of the factors that increase susceptibility of plants to Aspergillus and thus aflatoxin contamination.A recent drought is thought to be responsible for finding of trace amounts of aflatoxin in some of the corn harvested in the United States.Although it's too soon to know whether aflatoxin will be a significant problem,since United States is the world's largest corn producer and exporter,this has raised alarm bells.Strict regulations and testing of finished foods and feeds in the United States should prevent a major health scare,and prevent human exposure to deleterious levels of aflatoxin.Unfortunately,such regulations and testing are not in place in many countries.The purpose of this editorial is to summarize the current knowledge on association of aflatoxin and HCC,encourage future research and draw attention to this global public health issue.展开更多
Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for prevent...Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin Bl in human and animal bodies.Methods:In the present research,the bacteria were isolated from five different sources.For surveying the capability of the bacteria in isolating aflatoxin Bl,ELISA method was implemented,and for identifying the resultant strains through 16S rRNA sequencing method,universal primers were applied.Results:Among the strains which were isolated,two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin Bl by respectively absorbing and discharging 17.4%and 34.7%of the aforementioned toxin existing in the experiment solution.Conclusions:Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples,respectively.And both strains has the ability to isolate or bind with aflatoxin Bl.展开更多
Background:The current study was conducted to investigate the individual and combined occurrence of aflatoxin B_(1)(AFB_(1)),deoxynivalenol(DON)and zearalenone(ZEN)in feeds from various Provinces of China during 2018 ...Background:The current study was conducted to investigate the individual and combined occurrence of aflatoxin B_(1)(AFB_(1)),deoxynivalenol(DON)and zearalenone(ZEN)in feeds from various Provinces of China during 2018 to 2020.A total of 3,507 feed samples,including 2,090 feed ingredients and 1,417 complete feed samples,were collected from different areas of China for mycotoxins analysis.Results:The individual contamination of AFB_(1),DON and ZEN were present in more than 81.9%,96.4% and 96.9% of feed samples,respectively,with average concentration ranges of AFB_(1) between 1.2-27.4μg/kg,DON between 458.0-1,925.4μg/kg and ZEN between 48.1-326.8μg/kg.Notably,0.9%,0.5% and 0.1% of feed ingredients,and 1.2-12.8%,0.9-2.9% and 0-8.9% of complete feeds for pigs,poultry and ruminants with AFB_(1),ZEN and DON that exceeded China’s safety standards,respectively.Moreover,more than 81.5%of feed ingredients and 95.7% of complete feeds were co-contaminated with various combinations of these mycotoxins.Conclusion:This study indicates that the feeds in China were universally contaminated with AFB_(1),DON and ZEN during the past 3 years.These findings highlight the significance of monitoring mycotoxin contaminant levels in the domestic animal feed,and the importance of carrying out feed administration and remediation strategies for mycotoxin control.展开更多
AIM:To determine global DNA methylation in paired hepatocellular carcinoma(HCC) samples using several different assays and explore the correlations between hypomethylation and clinical parameters and biomarkers,includ...AIM:To determine global DNA methylation in paired hepatocellular carcinoma(HCC) samples using several different assays and explore the correlations between hypomethylation and clinical parameters and biomarkers,including that of aflatoxin B 1 exposure.METHODS:Using the radio labeled methyl acceptance assay as a measure of global hypomethylation,as well as two repetitive elements,including satellite 2(Sat2) by MethyLight and long interspersed nucleotide elements(LINE1),by pyrosequencing.RESULTS:By all three assays,mean methylation levels in tumor tissues were significantly lower than that in adjacent tissues.Methyl acceptance assay log(mean ± SD) disintegrations/min/ng DNA are 70.0 ± 54.8 and 32.4 ± 15.6,respectively,P = 0.040;percent methylation of Sat2 42.2 ± 55.1 and 117.9 ± 88.8,respectively,P < 0.0001 and percent methylation LINE1 48.6 ± 14.8 and 71.7 ± 1.4,respectively,P < 0.0001.Aflatoxin B 1 albumin(AFB 1-Alb) adducts,a measure of exposure to this dietary carcinogen,were inversely correlated with LINE1 methylation(r =-0.36,P = 0.034).CONCLUSION:Consistent hypomethylation in tumor compared to adjacent tissue was found by the three different methods.AFB 1 exposure is associated with DNA global hypomethylation,suggesting that chemical carcinogens may influence epigenetic changes in humans.展开更多
Chronic consumption of aflatoxin-contaminated foods is a global problem in both developing and developed countries especially where there is poor regulation of their levels in foods. In the body, aflatoxins (AFBs) mai...Chronic consumption of aflatoxin-contaminated foods is a global problem in both developing and developed countries especially where there is poor regulation of their levels in foods. In the body, aflatoxins (AFBs) mainly AFB1 are biotransformed to various metabolites especially the active AFB1-exo-8,9-epoxide (AFBO). The AFB, AFBO and other metabolites interact with various biomolecules in the body including nucleic acids such as DNA and RNA and the various metabolic pathways such as protein synthesis, glycolytic pathway and electron transport chain involved in ATP production in body cells. The AFB interacts with DNA to form AFB-DNA adducts causing DNA breakages. The AFB and its metabolites induce the up regulation of nuclear receptors such as pregnane X receptor (PXR), constitutive androstane receptor (CAR), and aryl hydrocarbon receptor (AhR) through gene expression that regulates the metabolizing enzymes such as CYP450 involved in Phase I and Phase II metabolism of xenobiotics. AFB activates these nuclear receptors to produce the metabolizing enzymes. The AFB1 is metabolized in the body by cytochrome P450 (CYP450) enzyme isoforms such as CYP1A2, CYP1A2, CYP3A4/ CYP3A5, and CYP3A7 in fetus, glutathione S-transferase, aflatoxin B1-aldehyde reductase leading to reactive metabolites, some of which can be used as aflatoxin exposure biomarkers. These enzymes are involved in the Phase I and Phase II metabolic reactions of aflatoxins. The CYP1A2 is the principal metabolizer of aflatoxin at low concentrations while the reverse is true for CYP3A4. The accumulation of AFB and its metabolites in the body especially the AFB1-exo-8,9-epoxide depletes the glutathione (GSH) due to the formation of high amounts of epoxides and other reactive oxygen species (ROS). The AFB, AFB1-exo-8,9-epoxide and other metabolites also affect the epigenetic mechanisms including the DNA methylation, histone modifications, maturation of miRNAs as well as the daily formation of single nucleotide polymorphism (SNP) where AFB exposure may facilitate the process and induces G:C to T:A transversions at the third base in codon 249 of TP53 causing p53 mutations reported in hepatocellular carcinoma (HCC). The changes in epigenetic mechanisms lead to either epigenetic inactivation or epigenetic derepression and all these affect the gene expression, cellular differentiation and growth. AFB also through epigenetic mechanisms promotes tumorigenesis, angiogenesis, invasion and metastasis in hepatocellular carcinoma. However, the formation of the small amounts of AFB1 from AFB2 is suspected to cause the carcinogenicity of AFB2 in humans and animals. Chronic aflatoxins exposure leads to formation of reactive AFBO metabolites in the body that could activate and de-activates the various epigenetic mechanisms leading to development of various cancers.展开更多
Objective:To assess the awareness and knowledge of aflatoxin contamination in groundnut and the risk of its ingestion among health workers in Ibadan.Methods:The study was a descriptive cross-sectional study.Study inst...Objective:To assess the awareness and knowledge of aflatoxin contamination in groundnut and the risk of its ingestion among health workers in Ibadan.Methods:The study was a descriptive cross-sectional study.Study instrument was a semi-structured self administered questionnaire. The respondents were health workers from a public health facility.Results:A total of 417 health workers participated out of which males were 60.2%.The mean age of respondents was(28.0±4.9) years old.Doctors made up 83.0%while others were nurses.95%of the respondents had previous awareness of aflatoxin and class room lectures was the most common source of information(56%).Occupation and religion both showed a significant association with previous awareness of aflatoxin(P<0.05).Knowledge regarding aflatoxin contamination in groundnut and the risk of its ingestion was obtained showing knowledge score range of 0 to 14.In all,80.6%had good scores of 11 to 14.None of the respondents had ever told their patients about the risk of aflatoxin ingestion. Conclusions:There is a need to explore the possibility of incorporating aflatoxin awareness into routine health talk to increase the level of awareness of patients and their relatives.展开更多
Mycotoxins and their derivatives since their discoveries and until the present time are behind unspecified economic and medical damages.Aflatoxins are classified according to their physical–chemical and toxicological...Mycotoxins and their derivatives since their discoveries and until the present time are behind unspecified economic and medical damages.Aflatoxins are classified according to their physical–chemical and toxicological characters in the most dangerous row of the mycotoxins.These aflatoxins are in part responsible,of irreversible medical disasters that are not easily manageable such as cancer of the liver and kidneys,and in the other part,of losses in the stored cereal products.Based on these crucial findings,monitoring of this toxin became imperative in post-harvest food products,during storage,during transformation chain and even during the long phases of conservation.Vigilance of this toxin is delivered by detection methods using very advanced technologies to respond in the shortest possible times.In addition,the knowledge of factors supporting the biosynthesis of aflatoxins such as the temperature,moisture content,concentration of nitrogen and carbon,and the molecules responsible for the genetic control of the synthesis will be reflected later in the choice of bio-control techniques.This control is currently based on new strategies using the bioactives substances of the plants,the lactic bacteria and some strains of actinomycetes that have good inhibiting activity against aflatoxins with fewer side effects on Man.On the other hand,this brief review summarizes the results of new studies demonstrating the toxicity of the toxin,new detection methods and bio-control.展开更多
Objective This study aimed to explore the protective effect of procyanidin B2(PCB2)on acute liver injury induced by aflatoxin B1(AFB1)in rats.Methods Forty Sprague Dawley rats were randomly divided into control,AFB1,A...Objective This study aimed to explore the protective effect of procyanidin B2(PCB2)on acute liver injury induced by aflatoxin B1(AFB1)in rats.Methods Forty Sprague Dawley rats were randomly divided into control,AFB1,AFB1+PCB2,and PCB2 groups.The latter two groups were administrated PCB2 intragastrically(30 mg/kg body weight)for 7 d,whereas the control and AFB1 groups were given the same dose of double distilled water intragastrically.On the sixth day of treatment,the AFB1 and AFB1+PCB2 groups were intraperitoneally injected with AFB1(2 mg/kg).The control and PCB2 groups were intraperitoneally administered the same dose of dimethyl sulfoxide(DMSO).On the eighth day,all rats were euthanized:serum and liver tissue were isolated for further examination.Hepatic histological features were assessed by hematoxylin and eosin-stained sections.Weight,organ coefficient(liver,spleen,and kidney),liver function(serum alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,total bilirubin,and direct bilirubin),oxidative index(catalase,glutathione,superoxide dismutase,malondialdehyde,and 8-hydroxy-2′-deoxyguanosine),inflammation factor[hepatic interleukin-6(IL-6)m RNA expression and serum IL-6],and bcl-2/bax ratio were measured.Results AFB1 significantly caused hepatic histopathological damage,abnormal liver function,oxidative stress,inflammation,and bcl-2/bax ratio reduction compared with DMSO-treated controls.Our results indicate that PCB2 treatment can partially reverse the adverse liver conditions induced by AFB1.Conclusion Our findings indicate that PCB2 exhibits a protective effect on acute liver injury induced by AFB1.展开更多
This study investigated the phytochemical screening of some plant extracts against aflatoxin producing fungi in sesame (Sesamum indicum). The plants are Prosopis africana, Psorospermum febrifugum and rhizome of Curcum...This study investigated the phytochemical screening of some plant extracts against aflatoxin producing fungi in sesame (Sesamum indicum). The plants are Prosopis africana, Psorospermum febrifugum and rhizome of Curcuma longa. Various parts of the plants were dried, grounded and extracted in methanolic solvent. The preliminary phytochemical screening of methanol extracts for stem bark, leaves and rhizome of Curcuma longa revealed the presence of saponins, flavonoids, steroids, cardiac, glycosides, terpenoids, phenols and tannins. The result of anti-aflatoxigenic activity indicates that methanol extracts of these plants show significant activity against the fungi isolates. The effect of plants extracts on mycelia growth of the test organism reduced the mycelia growth significantly as compared to the control (Plate 6 (a-f)). In view of the efficacy of the activity of the plant extracts, it could be concluded that these medicinal plants possess antifungal properties that can be exploited for the control of aflatoxin in sesame. Further works are needed to investigate the biological active ingredients of these plants.展开更多
Aflatoxins are the potent toxic, mutagenic, heterogenic and carcinogenic metabolites produced by species of A. flavus and A. parasiticus. In the present study, an attempt has been made to prevent aflatoxin production ...Aflatoxins are the potent toxic, mutagenic, heterogenic and carcinogenic metabolites produced by species of A. flavus and A. parasiticus. In the present study, an attempt has been made to prevent aflatoxin production using an anticancerous drug taxol. Taxol (Paclitaxel) is a well known drug for its anticancerous property mainly to treat breast and ovarian cancers. It was obtained from Taxus brevifolia and it was also obtained from the endophytic fungi present in Taxus brefivolia [1]. Therefore, this drug is specifically selected to screen its activity on the control of A. flavus and AFB1 production at various concentrations. Among the 6 concentrations used, 3 μg of taxol was found to be suitable to control the growth and AFB1 production. The content of AFB1 found at this concentration was 6 ppm by TLC and 6.3 ppm by HPTLC. The complete elimination of AFB1 might require higher concentrations of taxol.展开更多
Two important mycotoxins, aflatoxin and fumonisin, are among the most potent naturally occurring carcinogens, contaminating maize(Zea mays) and affecting crop yield and quality.Resistance of maize to pre-harvest mycot...Two important mycotoxins, aflatoxin and fumonisin, are among the most potent naturally occurring carcinogens, contaminating maize(Zea mays) and affecting crop yield and quality.Resistance of maize to pre-harvest mycotoxin contamination, specifically aflatoxin produced by Aspergillus flavus and fumonisin produced by Fusarium verticillioides, is a goal in breeding programs that screen for these important traits with the aim of developing resistant commercial hybrids. We conducted two years of field evaluations on 87 inbred lines originating primarily in China and Mexico and not previously screened for resistance.The objectives of our study were to identify resistant germplasm for breeding purposes and to examine possible relationships between resistances to the two mycotoxins. Aflatoxin and fumonisin were present in samples harvested from all lines in both years.Concentrations of total aflatoxin ranged from 52.00 ± 20.00 to 1524.00 ± 396.00 μg kg^(-1),while those of fumonisin ranged from 0.60 ± 0.06 to 124.00 ± 19.50 mg kg^(-1). The inbred lines TUN15, TUN61, TUN37, CY2, and TUN49 showed the lowest aflatoxin accumulation and CN1, GT601, TUN09, TUN61, and MP717 the lowest fumonisin accumulation. TUN61 showed the lowest accumulation of both mycotoxins. This study confirmed previous observations that high levels of aflatoxin can coexist with fumonisin, with 55 maize lines showing a positive correlation coefficient between the concentrations of aflatoxin and fumonisin and 32 lines showing a negative correlation coefficient. These selected lines,particularly TUN61, may provide sources of resistance to mycotoxin contamination in breeding programs. However, the mechanism of resistance in this germplasm remains to be identified. Future research should also address factors that influence the fungus–plant interaction, such as herbivory and environmental stress.展开更多
In the present study, the aflatoxin B1 contamination at various stages of oil refining and in refined oil were carried out. This was subsequently compared with commercial vegetable oil samples. Among the 23 different ...In the present study, the aflatoxin B1 contamination at various stages of oil refining and in refined oil were carried out. This was subsequently compared with commercial vegetable oil samples. Among the 23 different sunflower oil samples were tested, 10 of them showed posi-tive results to AFB1 and the remaining 13 showed negative results to AFB1. All the refined oil samples were free from AFB1 contamination.展开更多
In this study, we have used a direct immunoassay where the simple binding between antigen and an antibody is detected. Immunoassays were performed in a drop system, monitoring the frequency decrease of the quartz-crys...In this study, we have used a direct immunoassay where the simple binding between antigen and an antibody is detected. Immunoassays were performed in a drop system, monitoring the frequency decrease of the quartz-crystal microbalance device because of mass increasing during immunoreaction. The QCM sensor was coated on both sides by gold electrodes, only one side of the crystal (liquid side) was in contact with the solution;the other side (contact side) was always dry. We tested a piezoelectric immunosensor for aflatoxin B1 (AFLA-B1) mycotoxin detection through the immo- bilization of DSP-anti-AFLAB1 antibody (AFLA-B1-Ab anti AFLAB1) on gold-coated quartz crystals (AT-cut/5 MHz). The DSP (3,3’-Dithiodipropionic-acid-di-N-hydroxysuccinimide ester) was used for the covalent attachment of the proteins. The piezoelectric crystal electrodes were pretreated by DSP for 15 min, rinsed with water and dried in a gentle flow of nitrogen gas. Then the DSP-coated crystals were installed in a sample holder and exposed to the anti-AFLAB1 antibody and to the AFLA-BI. Frequency and resistance shifts (Δf and ΔR) were measured simultaneously. Δf versus AFLA-BI concentrations in the range of 0.5 - 10 ppb exhibited a perfect linear correlation with a coefficient of above 0.998.展开更多
Aflatoxins( AFs) are a major pollution source of grain pollution and are secondary metabolites produced by Aspergillus flavus and A.parasiticus,which are one of the most toxic and carcinogenic substances.Feeding anima...Aflatoxins( AFs) are a major pollution source of grain pollution and are secondary metabolites produced by Aspergillus flavus and A.parasiticus,which are one of the most toxic and carcinogenic substances.Feeding animals with aflatoxin-contaminated food can cause toxicosis,acute liver injury or liver cancer in animals,and also can cause multiple organ damage,decline in production performance and disease resistance,even death,which brings great economic losses to animal husbandry.In addition,AFs can do great harm to the human body.When the body ingests large amounts of AFs,it may suffer from acute poisoning and acute liver damage; and AFs can cause chronic poisoning of the body with continuous intake of trace AFs.This paper briefly analyzed the effect of AFs on the structure and function of poultry immune organs,immune gene expression,immunosuppression and so on.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61927813,61865009,and 12104203)Jiangxi Provincial Natural Science Foundation(Grant No.20212ACB201007).
文摘Terahertz metamaterial biosensors have attracted significant attention in the biological field due to their advantages of label-free,real-time and in situ detection.In this paper,a highly sensitive metamaterial sensor with semi-ring mirror symmetry based on toroidal dipole resonance is designed for a new metamaterial biosensor.It is shown that a refractive index sensitivity of 337.5 GHz per refractive index unit can be achieved under an analyte of saturated thickness near a 1.33 THz transmission dip.For biosensor samples where aflatoxin B1 is dropped on the metamaterial surface in our experiment,dip amplitudes of transmission varying from 0.1904 to 0.203 and 0.2093 are observed as aflatoxin B1 concentrations are altered from 0 to 0.001μg·ml-1 and to 0.01μg·ml-1,respectively.Furthermore,when aflatoxin B1 concentrations are 0.1μg·ml-1,1μg·ml-1,10μg·ml-1 and 100μg·ml-1,dip amplitudes of 0.2179,0.226,0.2384 and 0.2527 and dip redshifts of 10.1 GHz,20.1 GHz,27.7 GHz and 37.6 GHz are respectively observed.These results illustrate high-sensitivity,label-free detection of aflatoxin B1,enriching the applications of sensors in the terahertz domain.
基金funded by the grants from the China Agriculture Research System of MOF and MARA (CARS-41)the Agricultural Science and Technology Innovation Program, China (ASTIP-IAS04)。
文摘San-Huang chicken is a high-quality breed in China with yellow feather, claw and break. However, the abnormal phenomenon of the yellow shank turning into green shank of San-Huang chicken has been a concern, as it seriously reduces the carcass quality and economic benefit of yellow-feathered broilers. In this study, the cause of this abnormal green skin in shank was systematically investigated. Physiological anatomy revealed that the abnormal skin in shank was primarily due to the deposition of melanin under the dermis. After analyzing multiple potential causes such as heredity(pedigree and genetic markers), environment(water quality monitoring) and feed composition(mycotoxin detection), excessive aflatoxin B1(AFB1) in feed was screened, accompanied with a higher L-dihydroxy-phenylalanine(L-DOPA)(P<0.05) and melanin content(P<0.01). So it was speculated that excessive AFB1 might be the main cause of abnormal green skin in shank. Subsequently, the further results showed that a high concentration of AFB1(>170 μg kg–1)indeed induced the abnormal green skin in shank compared to the normal AFB1 content(<10 μg kg–1), and the mRNA levels of TYR, TYRP1, MITE, MC1R and EDN3 genes related to melanin deposition would significantly up-regulate(P<0.01) and the content and activity of tyrosinase(TyR) significantly increased(P<0.05). At the same time, the content of L-DOPA and melanin deposition also increased significantly(P<0.01), which also confirmed the effect of excessive AFB1 on melanin deposition in skin of shank. Results of additional experiments revealed that the AFB1's negative effect on melanin deposition in skin of shank could last for a longer time. Taken together, the results of this study explained the occurrence and possible mechanisms of the abnormal AFB1-related green skin in shank of chickens. Excessive AFB1 in diets increased the L-DOPA content and melanin abnormal deposition in the chicken shank possibly via promoting TyR content and activity, and the expression of melanin synthesis-related genes. Furthermore, our findings once again raised the alarm of the danger of AFB1 in the broiler production.
文摘Aflatoxin contamination of crops is frequent in warm regions across the globe, including large areas in sub-Saharan Africa and Burkina Faso. A?atoxins and fumonisins are among the mycotoxins that have been increasingly reported to affect health and productivity of livestock globally. It cuts across the value chain, affecting farmers, markets, and finally consumers. However, a?atoxin contamination is a threatening issue in these staples and its negative effects on human health, most especially on infants and young children, are very alarming. Among the cereals in Burkina Faso, the maize is more vulnerable to contamination by Aspergillus sp. The contamination of maize by the aflatoxin is the main cause affecting production of agricultural sector, food security and regularity. Many factors are responsible for its proliferating. Therefore aflatoxins reduction in cereals such as maize is a serious concern for quality and safety. This review aimed to highlight the factors influencing a?atoxins contamination, and methods of reduction.
文摘Aflatoxins are toxic metabolites present in various foods, especially when production and conservation do not respect good hygiene practices (GHP). In Ouagadougou, maize flour is produced and sold in different structures by actors who do not always respect GHP. Thus, it is necessary to regularly control the quality of these flours. So, this is carried out with the aim to assess the aflatoxin content of maize flours produced in the municipality of Ouagadougou. For this, twenty-eight (28) samples were collected from households, markets and supermarkets in the city of Ouagadougou. Thus, LC/MS/MS analysis was used to assess the aflatoxin content of the samples. The results obtained reveal the presence of total aflatoxins (AFT) in 78.57% of samples analyzed with levels ranging from 0.89 to 64.25 μg/kg. The prevalence of different types of aflatoxins were 57.14% for aflatoxin B1 (AFB1), 46.43% for aflatoxin B2 (AFB2), 42.86% for aflatoxin G1 (AFG1) and 4.6% for aflatoxin G2 (AFG2). The results also show that 80% and 60% of market samples, 70% and 30% of household samples and 37.5% and 25% of supermarket samples do not comply with European Commission standards for AFT and AFB1 respectively. For all the samples, 60.71% and 42.86% of the samples are compliant according to the limits established by the European Commission (EC) respectively for AFB1 and AFT. Regarding the results obtained, producers and processors must be supervised and trained in GHP for the production of better-quality flours.
文摘Method validation for quantitative analysis of aflatoxins, AFB1, AFB2, AFG1 and AFG2 in sorghum, peanut butter, groundnut and animals feed is presented. Aflatoxins were extracted with a mixture of methanol: acetonitrile: water (60:30:10) and cleaned with Alfa test IAC chromatography before analysis by High Performance Liquid Chromatography coupled with fluorescence detection (HPLC-FLD) by adopting an isocratic chromatographic system using a mobile phase consisting acetic acid: acetonitrile: methanol (59:14:27), the separation of the four aflatoxins was achieved in less than 15 minutes. Calibration curves were linear over the concentration range from 2 - 18 ng/mL for AFB1 and AFG1, 0.4 - 3.6 ng/mL for AFB2 and AFG2, respectively. The LOD and LOQ in spiked samples were found to be 0.02 and 0.05 μg/kg for both AFB1 and AFG1, 0.01 and 0.03 μg/kg for both AFB2 and AFG2. The mean recovery values were in range from 84.2% to 96.9% was obtained. Five samples were found to be contaminated with aflatoxins and the total aflatoxins ranged from 0.02 to 3.26 μg/kg were obtained. Nineteen different samples were found to be contaminated with aflatoxins;the total aflatoxins ranged from 0.27 to 10.48 μg/kg were obtained. The highest total aflatoxins value was obtained in animal feeds.
文摘Busia and Kisii Central districts are areas in western Kenya that have repeatedly reported high levels of stunting growth in children and an increase in hepatocellular carcinoma (HCC);an aspect often positively associated with chronic exposure to aflatoxins especially through consumption of foods such as peanuts. The objectives of the study were to determine the incidence, types and levels of aflatoxin in different varieties of peanuts produced in Busia and Kisii Central districts. One hundred and two (102) peanuts samples were collected from farmers’ in each district. Aflatoxin types and levels of aflatoxins were analyzed using high performance liquid chromatography (HPLC) technique. All the peanuts samples from Kisii Central and 97.06% samples from Busia were contaminated with aflatoxins. However, aflatoxin was not detected in 2.94% of samples from Busia district. The levels of total aflatoxin ranges were 0.1 to 268 μg/kg and 1.63 to 591.1 μg/kg in peanuts from Busia and Kisii Central respectively. Majority of peanuts samples had levels within Kenya Bureau of Standards (KEBS) and European Union (EU) regulatory limits for total aflatoxins. Improved variety (Valencia red) had significantly lower aflatoxin contamination compared to local varieties (Uganda local red, Homabay local and Local red). Aflatoxins B1, B2, G1 and G2 were found in peanuts;B1 was the most predominant in both districts (t = 12.4, df = 3, P = 0.034). The levels of aflatoxins especially in peanuts from Kisii Central district were high (591.1 μg/kg) where 44.6% of samples analyzed were unfit for even animal feed (USFDA regulatory limit). An assessment on the levels of aflatoxins should be done by the relevant stakeholders in other key foods in the areas for example maize. The most lethal aflatoxin type B1 was found to be the most predominant peanuts from both districts of study. This calls for frequent aflatoxin screening of peanuts from the districts particularly aflatoxin type B.
文摘Hepatocellular carcinoma(HCC) is one of the leading causes of cancer deaths worldwide,primarily affecting populations in the developing countries.Aflatoxin,a food contaminant produced by the fungi Aspergillus flavus and Aspergillus parasiticus,is a known human carcinogen that has been shown to be a causative agent in the pathogenesis of HCC.Aflatoxin can affect a wide range of food commodities including corns,oilseeds,spices,and tree nuts as well as milk,meat,and dried fruit.Many factors affect the growth of Aspergillus fungi and the level of aflatoxin contamination in food.Drought stress is one of the factors that increase susceptibility of plants to Aspergillus and thus aflatoxin contamination.A recent drought is thought to be responsible for finding of trace amounts of aflatoxin in some of the corn harvested in the United States.Although it's too soon to know whether aflatoxin will be a significant problem,since United States is the world's largest corn producer and exporter,this has raised alarm bells.Strict regulations and testing of finished foods and feeds in the United States should prevent a major health scare,and prevent human exposure to deleterious levels of aflatoxin.Unfortunately,such regulations and testing are not in place in many countries.The purpose of this editorial is to summarize the current knowledge on association of aflatoxin and HCC,encourage future research and draw attention to this global public health issue.
基金Supported by Razi Vaccine And Serum Research Institute,Arak Branch,Iran(Grant No.TUMS/CMBRC-89-001)
文摘Objective:To determine lactic acid bacteria's capability to enhance the process of binding and isolating aflatoxin B1 and to utilize such lactic acid bacteria as a food supplement or probiotic products for preventing absorption of aflatoxin Bl in human and animal bodies.Methods:In the present research,the bacteria were isolated from five different sources.For surveying the capability of the bacteria in isolating aflatoxin Bl,ELISA method was implemented,and for identifying the resultant strains through 16S rRNA sequencing method,universal primers were applied.Results:Among the strains which were isolated,two strains of Lactobacillus pentosus and Lactobacillus beveris exhibited the capability of absorbing and isolating aflatoxin Bl by respectively absorbing and discharging 17.4%and 34.7%of the aforementioned toxin existing in the experiment solution.Conclusions:Strains of Lactobacillus pentosus and Lactobacillus beveris were isolated from human feces and local milk samples,respectively.And both strains has the ability to isolate or bind with aflatoxin Bl.
基金supported by the Chinese Natural Science Foundation projects(32072775 and 31772636)National Key Research and Development Program of China(2016YFD0501207)JiangSu Aomai Bio-Technology Co.,Ltd.(Nanjing,China).
文摘Background:The current study was conducted to investigate the individual and combined occurrence of aflatoxin B_(1)(AFB_(1)),deoxynivalenol(DON)and zearalenone(ZEN)in feeds from various Provinces of China during 2018 to 2020.A total of 3,507 feed samples,including 2,090 feed ingredients and 1,417 complete feed samples,were collected from different areas of China for mycotoxins analysis.Results:The individual contamination of AFB_(1),DON and ZEN were present in more than 81.9%,96.4% and 96.9% of feed samples,respectively,with average concentration ranges of AFB_(1) between 1.2-27.4μg/kg,DON between 458.0-1,925.4μg/kg and ZEN between 48.1-326.8μg/kg.Notably,0.9%,0.5% and 0.1% of feed ingredients,and 1.2-12.8%,0.9-2.9% and 0-8.9% of complete feeds for pigs,poultry and ruminants with AFB_(1),ZEN and DON that exceeded China’s safety standards,respectively.Moreover,more than 81.5%of feed ingredients and 95.7% of complete feeds were co-contaminated with various combinations of these mycotoxins.Conclusion:This study indicates that the feeds in China were universally contaminated with AFB_(1),DON and ZEN during the past 3 years.These findings highlight the significance of monitoring mycotoxin contaminant levels in the domestic animal feed,and the importance of carrying out feed administration and remediation strategies for mycotoxin control.
基金Supported by A grant from the National Institute of Health,No. ES005116 and No.P30ES009089
文摘AIM:To determine global DNA methylation in paired hepatocellular carcinoma(HCC) samples using several different assays and explore the correlations between hypomethylation and clinical parameters and biomarkers,including that of aflatoxin B 1 exposure.METHODS:Using the radio labeled methyl acceptance assay as a measure of global hypomethylation,as well as two repetitive elements,including satellite 2(Sat2) by MethyLight and long interspersed nucleotide elements(LINE1),by pyrosequencing.RESULTS:By all three assays,mean methylation levels in tumor tissues were significantly lower than that in adjacent tissues.Methyl acceptance assay log(mean ± SD) disintegrations/min/ng DNA are 70.0 ± 54.8 and 32.4 ± 15.6,respectively,P = 0.040;percent methylation of Sat2 42.2 ± 55.1 and 117.9 ± 88.8,respectively,P < 0.0001 and percent methylation LINE1 48.6 ± 14.8 and 71.7 ± 1.4,respectively,P < 0.0001.Aflatoxin B 1 albumin(AFB 1-Alb) adducts,a measure of exposure to this dietary carcinogen,were inversely correlated with LINE1 methylation(r =-0.36,P = 0.034).CONCLUSION:Consistent hypomethylation in tumor compared to adjacent tissue was found by the three different methods.AFB 1 exposure is associated with DNA global hypomethylation,suggesting that chemical carcinogens may influence epigenetic changes in humans.
文摘Chronic consumption of aflatoxin-contaminated foods is a global problem in both developing and developed countries especially where there is poor regulation of their levels in foods. In the body, aflatoxins (AFBs) mainly AFB1 are biotransformed to various metabolites especially the active AFB1-exo-8,9-epoxide (AFBO). The AFB, AFBO and other metabolites interact with various biomolecules in the body including nucleic acids such as DNA and RNA and the various metabolic pathways such as protein synthesis, glycolytic pathway and electron transport chain involved in ATP production in body cells. The AFB interacts with DNA to form AFB-DNA adducts causing DNA breakages. The AFB and its metabolites induce the up regulation of nuclear receptors such as pregnane X receptor (PXR), constitutive androstane receptor (CAR), and aryl hydrocarbon receptor (AhR) through gene expression that regulates the metabolizing enzymes such as CYP450 involved in Phase I and Phase II metabolism of xenobiotics. AFB activates these nuclear receptors to produce the metabolizing enzymes. The AFB1 is metabolized in the body by cytochrome P450 (CYP450) enzyme isoforms such as CYP1A2, CYP1A2, CYP3A4/ CYP3A5, and CYP3A7 in fetus, glutathione S-transferase, aflatoxin B1-aldehyde reductase leading to reactive metabolites, some of which can be used as aflatoxin exposure biomarkers. These enzymes are involved in the Phase I and Phase II metabolic reactions of aflatoxins. The CYP1A2 is the principal metabolizer of aflatoxin at low concentrations while the reverse is true for CYP3A4. The accumulation of AFB and its metabolites in the body especially the AFB1-exo-8,9-epoxide depletes the glutathione (GSH) due to the formation of high amounts of epoxides and other reactive oxygen species (ROS). The AFB, AFB1-exo-8,9-epoxide and other metabolites also affect the epigenetic mechanisms including the DNA methylation, histone modifications, maturation of miRNAs as well as the daily formation of single nucleotide polymorphism (SNP) where AFB exposure may facilitate the process and induces G:C to T:A transversions at the third base in codon 249 of TP53 causing p53 mutations reported in hepatocellular carcinoma (HCC). The changes in epigenetic mechanisms lead to either epigenetic inactivation or epigenetic derepression and all these affect the gene expression, cellular differentiation and growth. AFB also through epigenetic mechanisms promotes tumorigenesis, angiogenesis, invasion and metastasis in hepatocellular carcinoma. However, the formation of the small amounts of AFB1 from AFB2 is suspected to cause the carcinogenicity of AFB2 in humans and animals. Chronic aflatoxins exposure leads to formation of reactive AFBO metabolites in the body that could activate and de-activates the various epigenetic mechanisms leading to development of various cancers.
文摘Objective:To assess the awareness and knowledge of aflatoxin contamination in groundnut and the risk of its ingestion among health workers in Ibadan.Methods:The study was a descriptive cross-sectional study.Study instrument was a semi-structured self administered questionnaire. The respondents were health workers from a public health facility.Results:A total of 417 health workers participated out of which males were 60.2%.The mean age of respondents was(28.0±4.9) years old.Doctors made up 83.0%while others were nurses.95%of the respondents had previous awareness of aflatoxin and class room lectures was the most common source of information(56%).Occupation and religion both showed a significant association with previous awareness of aflatoxin(P<0.05).Knowledge regarding aflatoxin contamination in groundnut and the risk of its ingestion was obtained showing knowledge score range of 0 to 14.In all,80.6%had good scores of 11 to 14.None of the respondents had ever told their patients about the risk of aflatoxin ingestion. Conclusions:There is a need to explore the possibility of incorporating aflatoxin awareness into routine health talk to increase the level of awareness of patients and their relatives.
文摘Mycotoxins and their derivatives since their discoveries and until the present time are behind unspecified economic and medical damages.Aflatoxins are classified according to their physical–chemical and toxicological characters in the most dangerous row of the mycotoxins.These aflatoxins are in part responsible,of irreversible medical disasters that are not easily manageable such as cancer of the liver and kidneys,and in the other part,of losses in the stored cereal products.Based on these crucial findings,monitoring of this toxin became imperative in post-harvest food products,during storage,during transformation chain and even during the long phases of conservation.Vigilance of this toxin is delivered by detection methods using very advanced technologies to respond in the shortest possible times.In addition,the knowledge of factors supporting the biosynthesis of aflatoxins such as the temperature,moisture content,concentration of nitrogen and carbon,and the molecules responsible for the genetic control of the synthesis will be reflected later in the choice of bio-control techniques.This control is currently based on new strategies using the bioactives substances of the plants,the lactic bacteria and some strains of actinomycetes that have good inhibiting activity against aflatoxins with fewer side effects on Man.On the other hand,this brief review summarizes the results of new studies demonstrating the toxicity of the toxin,new detection methods and bio-control.
基金financially supported by National Natural Science Foundation of China[No.31360383]。
文摘Objective This study aimed to explore the protective effect of procyanidin B2(PCB2)on acute liver injury induced by aflatoxin B1(AFB1)in rats.Methods Forty Sprague Dawley rats were randomly divided into control,AFB1,AFB1+PCB2,and PCB2 groups.The latter two groups were administrated PCB2 intragastrically(30 mg/kg body weight)for 7 d,whereas the control and AFB1 groups were given the same dose of double distilled water intragastrically.On the sixth day of treatment,the AFB1 and AFB1+PCB2 groups were intraperitoneally injected with AFB1(2 mg/kg).The control and PCB2 groups were intraperitoneally administered the same dose of dimethyl sulfoxide(DMSO).On the eighth day,all rats were euthanized:serum and liver tissue were isolated for further examination.Hepatic histological features were assessed by hematoxylin and eosin-stained sections.Weight,organ coefficient(liver,spleen,and kidney),liver function(serum alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,total bilirubin,and direct bilirubin),oxidative index(catalase,glutathione,superoxide dismutase,malondialdehyde,and 8-hydroxy-2′-deoxyguanosine),inflammation factor[hepatic interleukin-6(IL-6)m RNA expression and serum IL-6],and bcl-2/bax ratio were measured.Results AFB1 significantly caused hepatic histopathological damage,abnormal liver function,oxidative stress,inflammation,and bcl-2/bax ratio reduction compared with DMSO-treated controls.Our results indicate that PCB2 treatment can partially reverse the adverse liver conditions induced by AFB1.Conclusion Our findings indicate that PCB2 exhibits a protective effect on acute liver injury induced by AFB1.
文摘This study investigated the phytochemical screening of some plant extracts against aflatoxin producing fungi in sesame (Sesamum indicum). The plants are Prosopis africana, Psorospermum febrifugum and rhizome of Curcuma longa. Various parts of the plants were dried, grounded and extracted in methanolic solvent. The preliminary phytochemical screening of methanol extracts for stem bark, leaves and rhizome of Curcuma longa revealed the presence of saponins, flavonoids, steroids, cardiac, glycosides, terpenoids, phenols and tannins. The result of anti-aflatoxigenic activity indicates that methanol extracts of these plants show significant activity against the fungi isolates. The effect of plants extracts on mycelia growth of the test organism reduced the mycelia growth significantly as compared to the control (Plate 6 (a-f)). In view of the efficacy of the activity of the plant extracts, it could be concluded that these medicinal plants possess antifungal properties that can be exploited for the control of aflatoxin in sesame. Further works are needed to investigate the biological active ingredients of these plants.
文摘Aflatoxins are the potent toxic, mutagenic, heterogenic and carcinogenic metabolites produced by species of A. flavus and A. parasiticus. In the present study, an attempt has been made to prevent aflatoxin production using an anticancerous drug taxol. Taxol (Paclitaxel) is a well known drug for its anticancerous property mainly to treat breast and ovarian cancers. It was obtained from Taxus brevifolia and it was also obtained from the endophytic fungi present in Taxus brefivolia [1]. Therefore, this drug is specifically selected to screen its activity on the control of A. flavus and AFB1 production at various concentrations. Among the 6 concentrations used, 3 μg of taxol was found to be suitable to control the growth and AFB1 production. The content of AFB1 found at this concentration was 6 ppm by TLC and 6.3 ppm by HPTLC. The complete elimination of AFB1 might require higher concentrations of taxol.
基金partially supported by the U.S.Department of Agriculture-Agricultural Research Service(USDA-ARS)the Georgia Agricultural Commodity Commission for Corn+1 种基金the National Corn Growers AssociationAMCOE(Aflatoxin Mitigation Center of Excellence)
文摘Two important mycotoxins, aflatoxin and fumonisin, are among the most potent naturally occurring carcinogens, contaminating maize(Zea mays) and affecting crop yield and quality.Resistance of maize to pre-harvest mycotoxin contamination, specifically aflatoxin produced by Aspergillus flavus and fumonisin produced by Fusarium verticillioides, is a goal in breeding programs that screen for these important traits with the aim of developing resistant commercial hybrids. We conducted two years of field evaluations on 87 inbred lines originating primarily in China and Mexico and not previously screened for resistance.The objectives of our study were to identify resistant germplasm for breeding purposes and to examine possible relationships between resistances to the two mycotoxins. Aflatoxin and fumonisin were present in samples harvested from all lines in both years.Concentrations of total aflatoxin ranged from 52.00 ± 20.00 to 1524.00 ± 396.00 μg kg^(-1),while those of fumonisin ranged from 0.60 ± 0.06 to 124.00 ± 19.50 mg kg^(-1). The inbred lines TUN15, TUN61, TUN37, CY2, and TUN49 showed the lowest aflatoxin accumulation and CN1, GT601, TUN09, TUN61, and MP717 the lowest fumonisin accumulation. TUN61 showed the lowest accumulation of both mycotoxins. This study confirmed previous observations that high levels of aflatoxin can coexist with fumonisin, with 55 maize lines showing a positive correlation coefficient between the concentrations of aflatoxin and fumonisin and 32 lines showing a negative correlation coefficient. These selected lines,particularly TUN61, may provide sources of resistance to mycotoxin contamination in breeding programs. However, the mechanism of resistance in this germplasm remains to be identified. Future research should also address factors that influence the fungus–plant interaction, such as herbivory and environmental stress.
文摘In the present study, the aflatoxin B1 contamination at various stages of oil refining and in refined oil were carried out. This was subsequently compared with commercial vegetable oil samples. Among the 23 different sunflower oil samples were tested, 10 of them showed posi-tive results to AFB1 and the remaining 13 showed negative results to AFB1. All the refined oil samples were free from AFB1 contamination.
文摘In this study, we have used a direct immunoassay where the simple binding between antigen and an antibody is detected. Immunoassays were performed in a drop system, monitoring the frequency decrease of the quartz-crystal microbalance device because of mass increasing during immunoreaction. The QCM sensor was coated on both sides by gold electrodes, only one side of the crystal (liquid side) was in contact with the solution;the other side (contact side) was always dry. We tested a piezoelectric immunosensor for aflatoxin B1 (AFLA-B1) mycotoxin detection through the immo- bilization of DSP-anti-AFLAB1 antibody (AFLA-B1-Ab anti AFLAB1) on gold-coated quartz crystals (AT-cut/5 MHz). The DSP (3,3’-Dithiodipropionic-acid-di-N-hydroxysuccinimide ester) was used for the covalent attachment of the proteins. The piezoelectric crystal electrodes were pretreated by DSP for 15 min, rinsed with water and dried in a gentle flow of nitrogen gas. Then the DSP-coated crystals were installed in a sample holder and exposed to the anti-AFLAB1 antibody and to the AFLA-BI. Frequency and resistance shifts (Δf and ΔR) were measured simultaneously. Δf versus AFLA-BI concentrations in the range of 0.5 - 10 ppb exhibited a perfect linear correlation with a coefficient of above 0.998.
基金Supported by Program for International Cooperation of Ministry of Science and Technology(2011DFA30760)
文摘Aflatoxins( AFs) are a major pollution source of grain pollution and are secondary metabolites produced by Aspergillus flavus and A.parasiticus,which are one of the most toxic and carcinogenic substances.Feeding animals with aflatoxin-contaminated food can cause toxicosis,acute liver injury or liver cancer in animals,and also can cause multiple organ damage,decline in production performance and disease resistance,even death,which brings great economic losses to animal husbandry.In addition,AFs can do great harm to the human body.When the body ingests large amounts of AFs,it may suffer from acute poisoning and acute liver damage; and AFs can cause chronic poisoning of the body with continuous intake of trace AFs.This paper briefly analyzed the effect of AFs on the structure and function of poultry immune organs,immune gene expression,immunosuppression and so on.
