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Journal of Food Protection Jan 2021Almonds rejected as inedible are often used for production of almond oil. However, low-quality almonds are frequently contaminated with aflatoxins, and little is known...
ABSTRACT
Almonds rejected as inedible are often used for production of almond oil. However, low-quality almonds are frequently contaminated with aflatoxins, and little is known regarding transfer of aflatoxins to almond oil during processing. In this study, oil was produced from reject almonds by hexane extraction. Of 19 almond samples that were naturally contaminated with aflatoxins, 17 oil samples contained measurable amounts of aflatoxins, and aflatoxin content of contaminated oil was correlated with aflatoxin content of the nuts. However, oil aflatoxin levels were not correlated with the oxidation level of the oil as measured by percent free fatty acids and peroxide value. Adsorbents used in oil refining were tested for their ability to remove aflatoxins from contaminated oil. Fuller's earth and bentonite were the most effective, removing 96 and 86% of total aflatoxins from contaminated oil samples, respectively. Treatment with diatomaceous earth, in contrast, had no effect on aflatoxin levels in oil. These results show that oil refining steps using mineral clay adsorbents may also function to remove aflatoxins from contaminated oil.
Topics: Aflatoxins; Nuts; Plant Oils; Prunus dulcis
PubMed: 32882027
DOI: 10.4315/JFP-20-229 -
Toxicological Sciences : An Official... Mar 2011Since their discovery 50 years ago, the aflatoxins have become recognized as ubiquitous contaminants of the human food supply throughout the economically developing... (Review)
Review
Since their discovery 50 years ago, the aflatoxins have become recognized as ubiquitous contaminants of the human food supply throughout the economically developing world. The adverse toxicological consequences of these compounds in populations are quite varied because of a wide range of exposures leading to acute effects, including rapid death, and chronic outcomes such as hepatocellular carcinoma. Furthermore, emerging studies describe a variety of general adverse health effects associated with aflatoxin, such as impaired growth in children. Aflatoxin exposures have also been demonstrated to multiplicatively increase the risk of liver cancer in people chronically infected with hepatitis B virus (HBV) illustrating the deleterious impact that even low toxin levels in the diet can pose for human health. The public health impact of aflatoxin exposure is pervasive. Aflatoxin biomarkers of internal and biologically effective doses have been integral to the establishment of the etiologic role of this toxin in human disease through better estimates of exposure, expanded knowledge of the mechanisms of disease pathogenesis, and as tools for implementing and evaluating preventive interventions.
Topics: Aflatoxins; Animals; Environmental Exposure; Food Contamination; History, 20th Century; History, 21st Century; Humans; Poisons; Public Health; Toxicology; Translational Research, Biomedical
PubMed: 20881231
DOI: 10.1093/toxsci/kfq283 -
Molecules (Basel, Switzerland) Sep 2022Contamination of agricultural products and foods by aflatoxin B (AFB) is becoming a serious global problem, and the presence of AFB in edible oil is frequent and has... (Review)
Review
Contamination of agricultural products and foods by aflatoxin B (AFB) is becoming a serious global problem, and the presence of AFB in edible oil is frequent and has become inevitable, especially in underdeveloped countries and regions. As AFB results from a possible degradation of aflatoxins and the interaction of the resulting toxic compound with food components, it could cause chronic disease or severe cancers, increasing morbidity and mortality. Therefore, rapid and reliable detection methods are essential for checking AFB occurrence in foodstuffs to ensure food safety. Recently, new biosensor technologies have become a research hotspot due to their characteristics of speed and accuracy. This review describes various technologies such as chromatographic and spectroscopic techniques, ELISA techniques, and biosensing techniques, along with their advantages and weaknesses, for AFB control in edible oil and provides new insight into AFB detection for future work. Although compared with other technologies, biosensor technology involves the cross integration of multiple technologies, such as spectral technology and new nano materials, and has great potential, some challenges regarding their stability, cost, etc., need further studies.
Topics: Aflatoxin B1; Aflatoxins; Biosensing Techniques; Food Contamination; Food Safety
PubMed: 36234684
DOI: 10.3390/molecules27196141 -
Plant Disease Sep 2021Aflatoxins are potent mycotoxins that contaminate food and feed, thereby impacting health and trade. Biopesticides with atoxigenic isolates as active ingredients are...
Aflatoxins are potent mycotoxins that contaminate food and feed, thereby impacting health and trade. Biopesticides with atoxigenic isolates as active ingredients are used to reduce aflatoxin contamination in crops. The mechanism of aflatoxin biocontrol is primarily attributed to competitive exclusion but, sometimes, aflatoxin is reduced by greater amounts than can be explained by displacement of aflatoxin-producing fungi on the crop. Objectives of this study were to (i) evaluate the ability of atoxigenic genotypes to degrade aflatoxin B (AFB1) and (ii) characterize impacts of temperature, time, and nutrient availability on AFB1 degradation by atoxigenic . Aflatoxin-contaminated maize was inoculated with atoxigenic isolates in three separate experiments that included different atoxigenic genotypes, temperature, and time as variables. Atoxigenic genotypes varied in aflatoxin degradation but all degraded AFB1 >44% after 7 days at 30°C. The optimum temperature for AFB1 degradation was 25 to 30°C, which is similar to the optimum range for AFB1 production. In a time-course experiment, atoxigenics degraded 40% of AFB1 within 3 days, and 80% of aflatoxin was degraded by day 21. Atoxigenic isolates were able to degrade and utilize AFB1 as a sole carbon source in a chemically defined medium but quantities of AFB1 degraded declined as glucose concentrations increased. Degradation may be an additional mechanism through which atoxigenic biocontrol products reduce aflatoxin contamination pre- or postharvest. Thus, selection of optimal atoxigenic active ingredients can include assessment of both competitive ability in agricultural fields and their ability to degrade aflatoxins.
Topics: Aflatoxin B1; Aflatoxins; Aspergillus flavus; Biological Control Agents; Zea mays
PubMed: 33754847
DOI: 10.1094/PDIS-01-21-0066-RE -
BMJ Paediatrics Open Apr 2023Aflatoxin B1 (AFB1) is a carcinogen produced by and which grow on maize. Given the high prevalence of child stunting (ie, impaired growth) and other nutritional...
Assessment of aflatoxin exposure, growth faltering and the gut microbiome among children in rural Guatemala: protocol for an observational prospective cohort and bioreactor simulations.
INTRODUCTION
Aflatoxin B1 (AFB1) is a carcinogen produced by and which grow on maize. Given the high prevalence of child stunting (ie, impaired growth) and other nutritional disorders in low-income and middle-income countries, where maize is consumed, the role of aflatoxin exposure may be significant. Observational reports have demonstrated associations between aflatoxin exposure and impaired child growth; however, most have been cross-sectional and have not assessed seasonal variations in aflatoxin, food preparation and dynamic changes in growth. Biological mechanistic data on how aflatoxin may exert an impact on child growth is missing. This study incorporates a prospective cohort of children from rural Guatemala to assess (1) temporal associations between aflatoxin exposure and child growth and (2) possible mediation of the gut microbiome among aflatoxin exposure, inflammation and child growth.
METHODS AND ANALYSIS
We will prospectively evaluate aflatoxin exposure and height-for-age difference trajectories for 18 months in a cohort of 185 children aged 6-9 months at enrolment. We will assess aflatoxin exposure levels and biomarkers of gut and systemic inflammation. We will examine the faecal microbiome of each child and identify key species and metabolic pathways for differing AFB1 exposure levels and child growth trajectories. In parallel, we will use bioreactors, inoculated with faeces, to investigate the response of the gut microbiome to varying levels of AFB1 exposure. We will monitor key microbial metabolites and AFB1 biotransformation products to study nutrient metabolism and the impact of the gut microbiome on aflatoxin detoxification/metabolism. Finally, we will use path analysis to summarise the effect of aflatoxin exposure and the gut microbiome on child growth.
ETHICS AND DISSEMINATION
Ethics approval was obtained from Arizona State University Institutional Review Board (IRB; STUDY00016799) and Wuqu' Kawoq/Maya Health Alliance IRB (WK-2022-003). Findings will be disseminated in scientific presentations and peer-reviewed publications.
Topics: Child; Humans; Aflatoxin B1; Aflatoxins; Bioreactors; Cross-Sectional Studies; Gastrointestinal Microbiome; Guatemala; Inflammation; Prospective Studies; Zea mays; Observational Studies as Topic
PubMed: 37080609
DOI: 10.1136/bmjpo-2023-001960 -
International Journal of Molecular... Mar 2024Aflatoxins are harmful natural contaminants found in foods and are known to be hepatotoxic. However, recent studies have linked chronic consumption of aflatoxins to... (Review)
Review
Aflatoxins are harmful natural contaminants found in foods and are known to be hepatotoxic. However, recent studies have linked chronic consumption of aflatoxins to nephrotoxicity in both animals and humans. Here, we conducted a systematic review of active compounds, crude extracts, herbal formulations, and probiotics against aflatoxin-induced renal dysfunction, highlighting their mechanisms of action in both in vitro and in vivo studies. The natural products and dietary supplements discussed in this study alleviated aflatoxin-induced renal oxidative stress, inflammation, tissue damage, and markers of renal function, mostly in animal models. Therefore, the information provided in this review may improve the management of kidney disease associated with aflatoxin exposure and potentially aid in animal feed supplementation. However, future research is warranted to translate the outcomes of this study into clinical use in kidney patients.
Topics: Animals; Humans; Aflatoxins; Aflatoxin B1; Biological Products; Dietary Supplements; Kidney Diseases
PubMed: 38474096
DOI: 10.3390/ijms25052849 -
Toxins Mar 2023Aflatoxin contamination of maize is a major food safety issue worldwide. The problem is of special significance in African countries because maize is a staple food. This...
Aflatoxin contamination of maize is a major food safety issue worldwide. The problem is of special significance in African countries because maize is a staple food. This manuscript describes a low-cost, portable, non-invasive device for detecting and sorting aflatoxin-contaminated maize kernels. We developed a prototype employing a modified, normalized difference fluorescence index (NDFI) detection method to identify potentially aflatoxin-contaminated maize kernels. Once identified, these contaminated kernels can be manually removed by the user. The device consists of a fluorescence excitation light source, a tablet for image acquisition, and detection/visualization software. Two experiments using maize kernels artificially infected with toxigenic were implemented to evaluate the performance and efficiency of the device. The first experiment utilized highly contaminated kernels (71.18 ppb), while mildly contaminated kernels (1.22 ppb) were used for the second experiment. Evidently, the combined approach of detection and sorting was effective in reducing aflatoxin levels in maize kernels. With a maize rejection rate of 1.02% and 1.34% in the two experiments, aflatoxin reduction was achieved at 99.3% and 40.7%, respectively. This study demonstrated the potential of using this low-cost and non-invasive fluorescence detection technology, followed by manual sorting, to significantly reduce aflatoxin levels in maize samples. This technology would be beneficial to village farmers and consumers in developing countries by enabling safer foods that are free of potentially lethal levels of aflatoxins.
Topics: Aflatoxins; Zea mays; Aspergillus flavus; Food Contamination; Food
PubMed: 36977088
DOI: 10.3390/toxins15030197 -
BioMed Research International 2018The toxic effects and potential mechanisms of aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), and AFB1+AFM1 in the kidney were studied and compared in HEK 293 cells model and...
The toxic effects and potential mechanisms of aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), and AFB1+AFM1 in the kidney were studied and compared in HEK 293 cells model and CD-1 mice model. The 35-day subacute toxicity mice model was constructed, biochemical indicators and kidney pathological staining were detected, kidney metabonomics detection was performed, and the metabolites were analyzed, and then the related toxicity mechanism was validated. Results showed that AFB1 (0.5 mg/kg), AFM1 (3.5 mg/kg), and AFB1 (0.5 mg/kg)+AFM1 (3.5 mg/kg) activated oxidative stress and caused renal damage. The relative concentration of the metabolite L-proline was found to be lower in aflatoxins treatment groups when compared with the control ( < 0.05). Moreover, with the treatment of aflatoxins, proline dehydrogenase (PRODH) and proapoptotic factors (Bax, Caspase-3) were upregulated, while the inhibitor of apoptosis Bcl-2 was downregulated, at both the mRNA and the protein levels, comparing with the control ( < 0.05). In addition, the combined effect of AFB1 and AFM1 was validated, for the toxicity of the combination was stronger than the other two groups. In conclusion, AFB1 and AFM1 caused kidney toxicity by activating oxidative stress through altering expression of PRODH and L-proline levels, which then induced downstream apoptosis.
Topics: Aflatoxin B1; Aflatoxin M1; Aflatoxins; Animals; Apoptosis; Beijing; China; HEK293 Cells; Humans; Japan; Kidney; Mice; Proline; Singapore
PubMed: 30159329
DOI: 10.1155/2018/9074861 -
Toxins Sep 2023In this study, aflatoxins (AFs) and ochratoxin A (OTA) were analyzed in grains, specifically wheat and corn, from Albania. To summarize, 71 wheat and 45 corn samples...
In this study, aflatoxins (AFs) and ochratoxin A (OTA) were analyzed in grains, specifically wheat and corn, from Albania. To summarize, 71 wheat and 45 corn samples from different growing areas were collected. The multi-toxin analytical procedure involved sample extraction and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The incidence of AF was 18% in the analyzed wheat and 71% in the corn samples. The concentration of AFs was much higher in the corn samples than in the wheat samples. The maximum permitted levels for aflatoxin B1 (AFB1) and total AFs were not exceeded in the wheat samples, while they were exceeded in 36% of the corn samples. In the wheat samples, the AFB1 concentration varied between 0.2 and 0.4 µg kg. However, the highest concentrations in the corn samples were 2057, 2944, and 3550 µg kg. OTA was present in only three corn samples and one wheat sample. However, all contaminated samples exceeded the maximum permitted levels. This report reveals the presence of AFs and OTA in grain commodities, specifically wheat and corn, grown in Albania.
Topics: Aflatoxins; Zea mays; Triticum; Chromatography, Liquid; Albania; Incidence; Food Contamination; Tandem Mass Spectrometry; Ochratoxins; Aflatoxin B1; Chromatography, High Pressure Liquid
PubMed: 37755993
DOI: 10.3390/toxins15090567 -
Natural Product Reports Oct 2014In this viewpoint highlights are drawn from a deep analysis of the multifaceted problem of aflatoxin biosynthesis, one of the most highly rearranged polyketide natural... (Review)
Review
In this viewpoint highlights are drawn from a deep analysis of the multifaceted problem of aflatoxin biosynthesis, one of the most highly rearranged polyketide natural products known. Fundamental chemical insights have emerged into how cytochrome P450-mediated skeletal rearrangements occur through probable cationic intermediates and oxidative dearomatizations, which are applicable more widely in natural product catabolism. So to where current experimental methods have failed in our hands, bioinformatic tools and fresh experimental strategies have been developed to identify linker regions in large, polydomain proteins and guide the dissection and reassembly of their component parts. It has been possible to deduce individual catalytic roles, how overall synthesis is coordinated and how these enzymes can be re-engineered in a rational manner to prepare non-natural products. These insights and innovations were often not planned or anticipated, but sprung from the inability to answer fundamental questions. Advances in science can take place by chance favoring the prepared mind, other times by refusing to give up and devising new solutions to address hard questions. Both ways forward played important roles in the investigation of aflatoxin biosynthesis. For these contributions I am pleased to share this special issue of NPR with John Vederas and Tom Simpson, who have been leaders in this field for the last third of a century.
Topics: Aflatoxins; Molecular Structure; Polyketide Synthases; Polyketides
PubMed: 25079257
DOI: 10.1039/c4np00092g