RESUMEN
AFB1 is a harmful substance that can be found in agricultural products and can seriously affect human health, even in trace amounts. Therefore, monitoring AFB1 levels to ensure food safety and protect public health is crucial. New, highly reliable, selective, and rapid detection methods are needed to achieve this goal. Our work involves the development of a polymeric membrane sensor using radical polymerization that can accurately detect AFB1. Various spectroscopic techniques (Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM)) were used to obtain information about the structural and morphological properties of the prepared sensor. The sensor displayed fluorescence selectively responsive to AFB1 at the excitation wavelength of 376 nm and emission wavelength of 423 nm. The polymeric fluorescence sensor showed good sensitivity and a wide linear range from 9.61 × 10-10 and 9.61 × 10-9 mol/L for AFB1quantification. The limit of detection (LOD) is as low as 3.84 × 10-10 mol/L for AFB1. Other mycotoxins, such as aflatoxin B2 and aflatoxin G1, did not interfere with the sensor's high selectivity towards AFB1. To test the sensor's effectiveness in detecting AFB1 in real samples, three different grain samples - peanuts, hazelnut butter, and peanuts with a sauce known to contain AFB1 - were utilized. The results were satisfactory and demonstrated that the sensor can be successfully employed in real samples, with an error range of 0.43 % to 12.10 %.
Asunto(s)
Aflatoxina B1 , Límite de Detección , Espectrometría de Fluorescencia , beta-Ciclodextrinas , Aflatoxina B1/análisis , Espectrometría de Fluorescencia/métodos , beta-Ciclodextrinas/química , Espectroscopía Infrarroja por Transformada de Fourier , Contaminación de Alimentos/análisis , Grano Comestible/química , Polímeros/químicaRESUMEN
A sandwich electrochemical sensor was fabricated based on multi-walled carbon nanotubes/ordered mesoporous carbon/AuNP (MWCNTs/CMK-3/AuNP) nanocomposites and porous core-shell nanoparticles Au@PdNPs to achieve rapid and sensitive detection of AFB1 in complex matrices. MWCNTs/CMK-3/AuNP nanocomposite, which was prepared by self-assembly method, served as a substrate material to increase the aptamer loading and improve the conductivity and electrocatalytic activity of the electrode for the first signal amplification. Then, Au@PdNPs, which were synthesized by one-pot aqueous phase method, were applied as nanocarriers loaded with plenty of capture probe antibody (Ab) and signal molecule toluidine blue (Tb) to form the Au@PdNPs-Ab-Tb bioconjugates for secondary signal amplification. The sensing system could still significantly improve the signal output intensity even in the presence of ultra-low concentration target compound due to the dual signal amplification of MWCNTs/CMK-3/AuNP nanocomposites and Au@PdNPs-Ab-Tb. The method exhibited high selectivity, low detection limit (9.13 fg/mL), and strong stability to differentiate AFB1 from other mycotoxins. Furthermore, the sensor has been successfully applied to the quantitative determination of AFB1 in corn, malt, and six herbs, which has potential applications in food safety, quality control, and environmental monitoring.
Asunto(s)
Aflatoxina B1 , Técnicas Electroquímicas , Oro , Límite de Detección , Nanopartículas del Metal , Nanotubos de Carbono , Paladio , Oro/química , Nanopartículas del Metal/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Paladio/química , Aflatoxina B1/análisis , Aflatoxina B1/inmunología , Nanotubos de Carbono/química , Técnicas Biosensibles/métodos , Anticuerpos Inmovilizados/inmunología , Nanocompuestos/química , Aptámeros de Nucleótidos/química , Contaminación de Alimentos/análisis , Zea mays/química , ElectrodosRESUMEN
Food contamination with Aflatoxin B1 (AFB1) is a worldwide concern that adversely affects animal and human health. The study aimed to evaluate the protective effect of alpha lipoic acid (ALA) and/or co-enzyme Q10 (CQ10) against the harmful effects of AFB1 on the liver and kidneys. Fifty-six mature male Wistar Albino rats (180-200 g) were divided into seven groups, each with eight rats: (1) saline was given as a control, (2) ALA (100 mg/kg bw/day) was given by stomach gavage for fifteen days, and (3) CQ10 (10 mg/kg bw/day) was given by stomach gavage for fifteen days. Group (4) orally given AFB1 (2.5 mg/kg bw) on days 12th and 14th, (5) received AFB1 and ALA, (6) received AFB1 and CQ10, and (7) received AFB1, ALA, and CQ10, as previously described in the ALA, CQ10, and AFB1 groups. After the exposure to AFB1, a significant increase in liver markers (AST, ALT, ALP, and LDH) and renal function tests (BUN and creatinine) was observed compared with the control. ALA and/or CQ10 significantly reduced enzymes of liver and renal functions, as compared with AFB1. AFB1 exposure threw off the balance between oxidants and antioxidants. Still, ALA and/or CQ10 made oxidative stress (MDA, NO, and 8-OHdG) much lower and antioxidant activities (GSH, GSH-Px, SOD, and CAT) much higher. When we used the two together, the activities matched the control levels. Interestingly, this study shows that ALA and CQ10 significantly lowered IL-1ß, IL-6, and TNF-α levels compared to the control values when used together after AFB1 exposure caused robust inflammation. Some CQ10 treatment parameters significantly outperformed those of ALA. ALA and CQ10 together worked better than either one alone to protect against AFB1-induced toxicity in the hepatic and renal parenchyma in terms of reducing inflammation, preventing DNA damage, and fighting free radicals.
Asunto(s)
Aflatoxina B1 , Daño del ADN , Riñón , Hígado , Estrés Oxidativo , Ratas Wistar , Ácido Tióctico , Ubiquinona , Animales , Ácido Tióctico/farmacología , Aflatoxina B1/toxicidad , Masculino , Daño del ADN/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ratas , Ubiquinona/análogos & derivados , Ubiquinona/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Riñón/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/inducido químicamente , Antioxidantes/farmacologíaRESUMEN
Aflatoxin B1 (AFB1) accumulates in crops, where it poses a threat to human health. To detect AFB1, anti-AFB1 monoclonal antibodies have been developed and are widely used. While the sensitivity and specificity of these antibodies have been extensively studied, information regarding the atomic-level docking of AFB1 (and its derivatives) with these antibodies is limited. Such information is crucial for understanding the key interactions that are required for high affinity and specificity in aflatoxin binding. First, a 3D comparative model of anti-AFB1 antibody (Ab-4B5G6) was predicted from the sequence using RosettaAntibody. We then utilized RosettaLigand to dock AFB1 onto ten homology models, producing a total of 10,000 binding modes. Interestingly, the best-scoring mode predicted strong interactions involving four sites within the heavy chain: ALA33, ASN52, HIS95, and TRP99. Importantly, these strong binding interactions exclusively involve the variable domain of the heavy chain. The best-scoring mode with AFB1 was also obtained through AF multimer combined with RosettaLigand, and two interactions at TRP and HIS were consistent with those found by Rosetta antibody-ligand computational simulation. The role of tryptophan in π interactions in antibodies was confirmed through mutation experiments, and the resulting mutant (W99A) exhibited a >1000-fold reduction in binding affinity for AFB1 and analogs, indicating the effect of tryptophan on the stability of CDR-H3 region. Additionally, we evaluated the binding of two glycolic acid-derived molecular derivatives (with impaired hydrogen bonding potential), and these derivatives (AFB2-GA and AFG2-GA) demonstrated a very weak binding affinity for Ab-4B5G6. The heavy chain was successfully isolated, and its sensitivity and specificity were consistent with those of the intact antibody. The homology models of variable heavy (VH) single-domain antibodies were established by RosettaAntibody, and the docking analysis revealed the same residues, including Ala, His, and Trp. Compared to the potential binding mode of fragment variable (FV) region, the results from a model of VH indicated that there are seven models involved in hydrophobic interaction with TYR32, which is usually referred to as polar amino acid and has both hydrophobic and hydrophilic features depending on the circumstances. Our work encompasses the entire process of Rosetta antibody-ligand computational simulation, highlighting the significance of variable heavy domain structural design in enhancing molecular interactions.
Asunto(s)
Aflatoxina B1 , Anticuerpos Monoclonales , Simulación del Acoplamiento Molecular , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Ligandos , Aflatoxina B1/química , Aflatoxina B1/inmunología , Especificidad de Anticuerpos , Aflatoxinas/química , Afinidad de Anticuerpos , Conformación Proteica , Secuencia de Aminoácidos , Simulación por Computador , Humanos , Simulación de Dinámica MolecularRESUMEN
Food crops around the world are commonly contaminated with Aspergillus flavus, which can produce the carcinogenic mycotoxin aflatoxin B1 (AFB1). The objective of this study is to test an X-ray irradiation sterilization method for studying AFB1 in contaminated maize samples in the laboratory. Maize that had been naturally contaminated with 300 ppb AFB1 by the growth of aflatoxigenic A. flavus was ground and then irradiated at 0.0, 1.0, 1.5, 2.0, 2.5, and 3.0 kGy. A. flavus was quantified by dilution plating on potato dextrose agar (PDA) and modified Rose Bengal media (MDRB) for viability and qPCR for gene presence. AFB1 was quantified by HPLC and ELISA. A. flavus viability, but not gene copies, significantly decreased with increasing doses of radiation (PDA: p < 0.001; MDRB: p < 0.001; qPCR: p = 0.026). AFB1 concentration did not significantly change with increasing doses of radiation (HPLC: p = 0.153; ELISA: p = 0.567). Our results imply that X-ray irradiation is an effective means of reducing viable A. flavus without affecting AFB1 concentrations. Reducing the hazard of fungal spores and halting AFB1 production at the targeted dose are important steps to safely and reproducibly move forward research on the global mycotoxin challenge.
Asunto(s)
Aflatoxina B1 , Aspergillus flavus , Zea mays , Zea mays/microbiología , Zea mays/efectos de la radiación , Aflatoxina B1/efectos de la radiación , Aspergillus flavus/efectos de la radiación , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/metabolismo , Aspergillus flavus/efectos de los fármacos , Rayos X , Contaminación de Alimentos/prevención & control , Irradiación de Alimentos/métodos , Viabilidad Microbiana/efectos de la radiación , Viabilidad Microbiana/efectos de los fármacosRESUMEN
Mycotoxins have strong immunotoxicity and can induce oxidative stress and mitochondrial dynamics imbalance. Mitochondrial antiviral signaling protein (MAVS) in the RIG-I like receptor (RLR) pathway of innate immunity is located on mitochondria, and whether it is affected by mycotoxins has not been reported yet. This experiment used porcine alveolar macrophages (PAM) to evaluate the antagonism of three isomers of chlorogenic acid (chlorogenic acid, isochlorogenic acid A, and neochlorogenic acid) against combined mycotoxins (Aflatoxin B1, Deoxynivalenol, and Ochratoxin A) induced mitochondrial damage and their effects on the RLR pathway, providing assistance for further elucidating the mechanism of mycotoxin immunotoxicity. Western blotting, enzyme linked immunosorbent assay (ELISA), and flow cytometry were used to detect relevant indicators. All three types of chlorogenic acid treatment can antagonize the cytotoxicity induced by combined mycotoxins, especially isochlorogenic acid A, which can protect cells from mycotoxins damage by maintaining mitochondrial dynamic homeostasis and improving innate immune function related to the RLR pathway.
Asunto(s)
Ácido Clorogénico , Inmunidad Innata , Macrófagos Alveolares , Dinámicas Mitocondriales , Micotoxinas , Tricotecenos , Animales , Ácido Clorogénico/farmacología , Ácido Clorogénico/análogos & derivados , Micotoxinas/toxicidad , Porcinos , Dinámicas Mitocondriales/efectos de los fármacos , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Tricotecenos/toxicidad , Inmunidad Innata/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Ocratoxinas/toxicidad , Aflatoxina B1/toxicidad , Células Cultivadas , Transducción de Señal/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacosRESUMEN
BACKGROUND: Aflatoxin B1, which can penetrate the blood-brain barrier and kill neural cells, can contaminate traditional herbal medicines, posing a significant risk to human health. The present study examined cellular, cognitive and behavioral consequences of aflatoxin B1 contamination of the anti-osteoporotic medicine Radix Dipsaci. METHODS: A mouse model of osteoporosis was created by treating the animals with all-trans-retinoic acid. Then the animals were treated intragastically with water decoctions of Radix Dipsaci that contained detectable aflatoxin B1 or not. The animals were compared in terms of mineral density and mineral salt content of bone, production of pro-inflammatory factors, neurogenesis and microglial activation in hippocampus, as well as behavior and cognitive function. RESULTS: Contamination of Radix Dipsaci with aflatoxin B1 significantly reduced the medicine's content of bioactive saponins. It destroyed the ability of the herbal decoction to improve mineral density and mineral salt content in the bones of diseased mice, and it induced the production of the oxidative stress marker malondialdehyde as well as the pro-inflammatory cytokines interleukin-1ß and tumor necrosis factor-α. Aflatoxin B1 contamination inhibited formation of new neurons and increased the proportion of activated microglia in the hippocampus. These neurological changes were associated with anhedonia, behavioral despair, and deficits in short-term memory and social memory. CONCLUSION: Contamination of Radix Dipsaci with aflatoxin B1 not only eliminates the herbal decoction's anti-osteoporotic effects, but it also induces neurotoxicity that can lead to cognitive decline and behavioral abnormalities. Such contamination should be avoided through tightly regulated production and quality control of medicinal herbs.
Asunto(s)
Aflatoxina B1 , Cognición , Modelos Animales de Enfermedad , Hipocampo , Neurogénesis , Osteoporosis , Animales , Hipocampo/efectos de los fármacos , Aflatoxina B1/toxicidad , Ratones , Osteoporosis/tratamiento farmacológico , Osteoporosis/inducido químicamente , Cognición/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Dipsacaceae/química , Masculino , Contaminación de Medicamentos , Medicamentos Herbarios Chinos/farmacologíaRESUMEN
Aflatoxin is one of the most notorious mycotoxins, of which aflatoxin B1 (AFB1) is the most harmful and prevalent. Microbes play a crucial role in the environment for the biotransformation of AFB1. In this study, a bacterial consortium, HS-1, capable of degrading and detoxifying AFB1 was obtained. Here, we combined multi-omics and cultivation-based techniques to elucidate AFB1 biotransformation by consortium HS-1. Co-occurrence network analysis revealed that the key taxa responsible for AFB1 biotransformation in consortium HS-1 mainly belonged to the phyla Proteobacteria and Actinobacteria. Moreover, metagenomic analysis showed that diverse microorganisms, mainly belonging to the phyla Proteobacteria and Actinobacteria, carry key functional enzymes involved in the initial step of AFB1 biotransformation. Metatranscriptomic analysis indicated that Paracoccus-related bacteria were the most active in consortium HS-1. A novel bacterium, Paracoccus sp. strain XF-30, isolated from consortium HS-1, contains a novel dye-decolorization peroxidase (DyP) enzyme capable of effectively degrading AFB1. Taxonomic profiling by bioinformatics revealed that DyP, which is involved in the initial biotransformation of AFB1, is widely distributed in metagenomes from various environments, primarily taxonomically affiliated with Proteobacteria and Actinobacteria. The in-depth examination of AFB1 biotransformation in consortium HS-1 will help us to explore these crucial bioresources more sensibly and efficiently.
Asunto(s)
Actinobacteria , Aflatoxina B1 , Biotransformación , Proteobacteria , Aflatoxina B1/metabolismo , Actinobacteria/metabolismo , Actinobacteria/genética , Proteobacteria/metabolismo , Proteobacteria/genética , Paracoccus/metabolismo , Paracoccus/genética , Biodegradación AmbientalRESUMEN
The long-term operation feature of enzymatic biofuel cell-based self-powered biosensor (EBFC-SPB) endows them with the potential to execute dual-signal biosensing without having to integrate an extra signal acquisition device. Herein, cobalt and manganese codoped CeO2 nanospheres (CoMn-CeO2 NSs) with glucose-oxidase-like and peroxidase-like activities have been developed as substrate-switched dual-channel signal transduction components in EBFC-SPB for a dual-signal assay of aflatoxin B1 (AFB1). The CoMn-CeO2 NSs modified with aptamer are anchored to a complementary DNA-attached bioanode of EBFC-SPB by base complementary pairing, which catalyze the glucose oxidation together with the glucose oxidase (GOx) on the bioanode. Once the AFB1 appears, CoMn-CeO2 NSs will be released from the bioanode due to the binding specificity of the aptamer, resulting in a decreased catalytic efficiency and the first declining stage of EBFC-SPB. Accompanied by the introduction of H2O2, the residual CoMn-CeO2 NSs on the bioanode switch to peroxidase-like activity and mediate the production of benzo-4-chlorohexadienone (4-CD) precipitate, which increases the steric hindrance and yields another declining stage of EBFC-SPB. By assessing the variation amplitudes during these two declining stages, the dual-signal assay of AFB1 has been realized with satisfying results. This work not only breaks ground in dual-signal bioassays but also deepens the application of nanozymes in EBFC-SPB.
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Aflatoxina B1 , Técnicas Biosensibles , Cerio , Técnicas Electroquímicas , Nanosferas , Aflatoxina B1/análisis , Aflatoxina B1/metabolismo , Nanosferas/química , Técnicas Biosensibles/métodos , Cerio/química , Glucosa Oxidasa/metabolismo , Glucosa Oxidasa/química , Cobalto/química , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Manganeso/químicaRESUMEN
The toxicity of the contaminated powder contributed to toxic aflatoxins has been well-known in the literature. However, before this study, the specific fungal strain behind aflatoxin production remained unidentified. Our research aimed to isolate and identify fungi from the tainted sandwiches while also assessing the preservation of sandwiches in ambient conditions. The study pinpointed Aspergillus flavus as the fungus responsible for aflatoxin production. Analysis revealed that the sandwich samples contaminated with pure A. flavus exhibited a significant Aflatoxin B1 (AFB1) concentration of 55.2 ± 0.21 ng/g, accompanied by a spore count of 2 × 106 Colony-Forming Unit (CFU)/g after ten days. In contrast, sandwich samples contaminated with the unspecified fungi displayed a lower AFB1 content of 16.21 ± 0.42 ng/g, with a spore count of 2.2 × 102 CFU/g after the same duration. In the prevention study, the efficacy of the ethanol spray method for inhibiting aflatoxin from A. flavus was investigated. Results demonstrated that a 70 % ethanol concentration at a ratio of 2.0 % total weight of the sandwich proved highly effective, significantly impeding fungal growth. This method extended the preservation time by sevenfold compared to the control. Importantly, tests at 2.0 % ethanol of the sandwich weight did not detect aflatoxin presence.
Asunto(s)
Aflatoxina B1 , Aflatoxinas , Aspergillus flavus , Contaminación de Alimentos , Microbiología de Alimentos , Aspergillus flavus/metabolismo , Aspergillus flavus/crecimiento & desarrollo , Aflatoxina B1/metabolismo , Aflatoxina B1/análisis , Contaminación de Alimentos/análisis , Aflatoxinas/análisis , Aflatoxinas/metabolismo , Esporas Fúngicas/crecimiento & desarrollo , Etanol/metabolismo , Recuento de Colonia Microbiana , Hongos/metabolismo , Hongos/aislamiento & purificación , Hongos/efectos de los fármacos , Conservación de Alimentos/métodosRESUMEN
INTRODUCTION: Aflatoxin B1 (AFB1) is a potent hepatocarcinogenic mycotoxin found in animal feed and human food components. AFB1 contamination poses severe food safety and economic consequences. METHODS: In this study, we used a coumarin-selective medium to isolate bacterial strains that can remove AFB1. Among the isolated bacterial strains, strain c4a exhibited the highest AFB1 removal activity. This strain was subjected to biochemical and phylogenetic characterization. The AFB1 removal activity of the extracellular supernatant of this strain was optimized for growth medium, reaction temperature, pH, and metal ions. The degradation products were analyzed using UPLC-ESI MS/MS. RESULTS: Strain c4a was found to be most closely related to Chryseobacterium timonianum. The extracellular supernatant of C. timonianum c4a grown in a modified nutrient broth (with gelatin peptone and beef extract in a 4:1 ratio) demonstrated the highest AFB1 removal activity when incubated with 1 ppm AFB1 at 60°C, pH 8, and Mn2+ or Mg2+ supplementation for 72 h. Surprisingly, the autoclaved extracellular supernatant also retained AFB1 removal activity. UPLC-ESI MS/MS analysis suggested that AFB1 was transformed into a metabolite (m/z value 285.08) by water molecule addition on furan ring double bond. CONCLUSION: The AFB1 removal activity of C. timonianum c4a was extracellular, constitutive, and highly thermostable, structurally transforming AFB1 into a much less toxic product. Herein, we present the first evidence of thermostable AFB1 removal activity of a strain belonging to C. timonianum.
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Aflatoxina B1 , Chryseobacterium , Espectrometría de Masas en Tándem , Aflatoxina B1/metabolismo , Chryseobacterium/aislamiento & purificación , Filogenia , Concentración de Iones de Hidrógeno , Temperatura , Medios de Cultivo/química , Contaminación de Alimentos/análisis , ARN Ribosómico 16S/genéticaRESUMEN
Foodborne hazardous factors pose a significant risk to public health, emphasizing the need for the development of sensitive and user-friendly detection strategies to effectively manage and control these risks in the food supply chain. Pyrococcus furiosus argonaute (PfAgo)-based biosensing approaches have been extensively explored due to its built-in signal amplification. However, the property that PfAgo is a DNA-guided DNA endonuclease has enabled almost all the existing PfAgo-based reports to be used for the detection of nucleic acids. To lend PfAgo toolbox to extended non-nucleic acid detection, we systematically investigated the mechanism characteristic of PfAgo' preference for guide DNA (gDNA) and proposed a gDNA dephosphorylation-modulated PfAgo sensor for the detection of non-nucleic acid targets. Our results indicated that PfAgo exhibits preference for 5'-phosphorylated gDNA at a specific ratio of PfAgo to gDNA concentration. Leveraging this PfAgo' preference and the dephosphorylation activity of alkaline phosphatase (ALP), ALP could be detected as low as 2.7 U/L. Furthermore, the PfAgo was coupled with immunolabelled ALP to develop a PfAgo-based fluorescence immunosensor, which achieves aflatoxins B1 detection with a detection limit of 29.89 pg/mL and exhibits satisfactory recoveries in wheat and maize samples. The developed method broadens the application scope of PfAgo toolbox, and provides a simple, sensitive, and universal detection platform for a variety targets.
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Aflatoxina B1 , Fosfatasa Alcalina , Técnicas Biosensibles , Pyrococcus furiosus , Técnicas Biosensibles/métodos , Pyrococcus furiosus/enzimología , Aflatoxina B1/análisis , Fosfatasa Alcalina/metabolismo , Fosfatasa Alcalina/química , Proteínas Argonautas/metabolismo , Límite de Detección , ADN/química , Fosforilación , Fluorescencia , Contaminación de Alimentos/análisisRESUMEN
This study aimed to assess the effectiveness of aflatoxin B1 (AFB1) and Thunbergia laurifolia extract (TLE) in the diets of Cherry Valley ducklings. Our investigation covered growth indicators, blood biochemical indices, meat quality, intestinal morphology, immune response, and CP450 enzyme-related gene expression. We conducted the study with 180 seven-day-old Cherry Valley ducks, randomly divided into five dietary treatments. These treatments included a basal diet without AFB1 (T1 group), TLE, or a commercial binder; the basal diet containing 0.1 mg AFB1/kg (T2 group), 0.1 mg AFB1/kg and 100 mg TLE/kg (T3 group), 0.1 mg AFB1/kg and 200 mg TLE/kg (T4 group), and 0.1 mg AFB1/kg and 0.5 g/kg of a commercial binder (T5 group), respectively. Ducklings fed with the T2 diet exhibited lower final body weight (BW), average body weight gain (ADG), and poor feed conversion ratio (FCR) during the 42-day trials. However, all ducklings in the T3, T4, and T5 groups showed significant improvements in final BW, ADG, and FCR compared to the T2 group. Increased alanine transaminase (ALT) concentration and increased expression of CYP1A1 and CYP1A2 indicated hepatotoxicity in ducklings fed the T2 diet. In contrast, ducklings fed T3, T4, and T5 diets all showed a decrease in the expression of CYP1A1 and CYP1A2, but only the T4 treatment group showed improvement in ALT concentration. AFB1 toxicity considerably raised the crypt depth (CD) in both the duodenum and jejunum of the T2 group, while the administration of 200 mg TLE/kg (T4) or a commercial binder (T5) effectively reduced this toxicity. Additionally, the villus width of the jejunum in the T2 treatment group decreased significantly, while all T3, T4, and T5 groups showed improvement in this regard. In summary, T. laurifolia extract can detoxify aflatoxicosis, leading to growth reduction and hepatic toxicosis in Cherry Valley ducklings.
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Antioxidantes , Patos , Extractos Vegetales , Animales , Extractos Vegetales/farmacología , Antioxidantes/farmacología , Alimentación Animal/análisis , Enfermedades de las Aves de Corral/tratamiento farmacológico , Enfermedades de las Aves de Corral/inducido químicamente , Aflatoxina B1/toxicidad , Micotoxicosis/tratamiento farmacológico , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Envenenamiento por AflatoxinasRESUMEN
In the context of the potential immunomodulatory properties of curcumin in counteracting the detrimental effects of concurrent exposure to Deoxynivalenol (DON) and Aflatoxin B1 (AFB1), a comprehensive 28-days trial was conducted utilizing 60 randomly allocated mice divided into four groups. Administration of curcumin at a dosage of 5 mg/kg body weight in conjunction with DON at 0.1 mg/kg and AFB1 at 0.01 mg/kg body weight was undertaken to assess its efficacy. Results indicated that curcumin intervention demonstrated mitigation of splenic structural damage, augmentation of serum immunoglobulin A (IgA) and immunoglobulin G (IgG) levels, elevation in T lymphocyte subset levels, and enhancement in the mRNA expression levels of pro-inflammatory cytokines TNF-α, IFN-γ, IL-2, and IL-6. Furthermore, curcumin exhibited a suppressive effect on apoptosis in mice, as evidenced by decreased activity of caspase-3 and caspase-9, reduced expression levels of pro-apoptotic markers Bax and Cytochrome-c (Cyt-c) at both the protein and mRNA levels, and the maintenance of a balanced expression ratio of mitochondrial apoptotic regulators Bax and Bcl-2. Collectively, these findings offer novel insights into the therapeutic promise of curcumin in mitigating immunosuppression and apoptotic events triggered by mycotoxin co-exposure.
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Aflatoxina B1 , Apoptosis , Curcumina , Citocinas , Bazo , Tricotecenos , Animales , Tricotecenos/toxicidad , Curcumina/farmacología , Aflatoxina B1/toxicidad , Apoptosis/efectos de los fármacos , Bazo/efectos de los fármacos , Bazo/inmunología , Ratones , Citocinas/metabolismo , Citocinas/genética , MasculinoRESUMEN
Aflatoxin B1 (AFB1) and ochratoxin A (OTA) are highly toxic mycotoxins present in food and feed, posing serious health risks to humans and animals. This study aimed to validate an efficient and cost-effective analytical method for quantifying AFB1 and OTA in rat urine using immunoaffinity column extraction and liquid chromatography with fluorescence detection (IAC-LC-FD). Additionally, the study evaluated the effect of incorporating fermented whey and pumpkin into the feed on the urinary excretion of these mycotoxins. The limits of detection and quantification were determined to be 0.1 µg/kg and 0.3 µg/kg, respectively, for both mycotoxins in feed, and 0.2 ng/mL and 0.6 ng/mL, respectively, in urine. The method demonstrated robust recovery rates ranging from 74% to 119% for both AFB1 and OTA in both matrices. In feed samples, the levels of AFB1 and OTA ranged from 4.3 to 5.2 µg/g and from 5.4 to 8.8 µg/g, respectively. This validated method was successfully applied to analyze 116 urine samples from rats collected during the fourth week of an in vivo trial. The results indicated that the addition of fermented whey and pumpkin to the feed influenced mycotoxin excretion in urine, with variations observed based on the sex of the rats, type of mycotoxin, and exposure dosage.
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Aflatoxina B1 , Ocratoxinas , Animales , Ocratoxinas/orina , Aflatoxina B1/orina , Masculino , Femenino , Ratas , Alimentación Animal/análisis , Cromatografía Liquida , Suero Lácteo/química , Ratas Sprague-Dawley , Contaminación de Alimentos/análisis , Espectrometría de FluorescenciaRESUMEN
The climate-change-coupled fungal burden in crop management and the need to reduce chemical pesticide usage highlight the importance of finding sustainable ways to control Aspergillus flavus. This study examines the effectiveness of 50 Pseudomonas isolates obtained from corn rhizospheres against A. flavus in both solid and liquid co-cultures. The presence and quantity of aflatoxin B1 (AFB1) and AFB1-related compounds were determined using high-performance liquid chromatography-high resolution mass spectrometry analysis. Various enzymatic- or non-enzymatic mechanisms are proposed to interpret the decrease in AFB1 production, accompanied by the accumulation of biosynthetic intermediates (11-hydroxy-O-methylsterigmatocystin, aspertoxin, 11-hydroxyaspertoxin) or degradation products (the compounds C16H10O6, C16H14O5, C18H16O7, and C19H16O8). Our finding implies the upregulation or enhanced activity of fungal oxidoreductases and laccases in response to bacterial bioactive compound(s). Furthermore, non-enzymatic reactions resulted in the formation of additional degradation products due to acid accumulation in the fermented broth. Three isolates completely inhibited AFB1 or any AFB1-related compounds without significantly affecting fungal growth. These bacterial isolates supposedly block the entire pathway for AFB1 production in the fungus during interaction. Apart from identifying effective Pseudomonas isolates as potential biocontrol agents, this work lays the foundation for exploring new bacterial bioactive compounds.
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Aflatoxina B1 , Aspergillus flavus , Pseudomonas , Zea mays , Aflatoxina B1/metabolismo , Aflatoxina B1/biosíntesis , Pseudomonas/metabolismo , Aspergillus flavus/metabolismo , Aspergillus flavus/crecimiento & desarrollo , Zea mays/microbiología , RizosferaRESUMEN
BACKGROUND: Mycotoxins, a class of secondary metabolites produced by molds, are widely distributed in nature and are very common in food contamination. Aflatoxin B1 (AFB1) is a highly stable natural mycotoxin, and many agricultural products are easily contaminated by AFB1, it is important to establish a sensitive and efficient AFB1 detection method for food safety. The fluorescence aptamer sensor has shown satisfactory performance in AFB1 detection, but most of the fluorescence aptasensors are not sensitive enough, so improving the sensitivity of the aptasensor becomes the focus of this work. RESULTS: Herein, an innovative fluorescent aptasensor for AFB1 detection which is based on catalytic hairpin assembly (CHA) and rolling circle amplification (RCA) driven by triple helix molecular switch (THMS) is proposed. A functional single-strand with an AFB1 aptamer, here called an APF, is first designed to lock onto the signal transduction probe (STP), which separates from THMS when target AFB1 is present. Subsequently, STP initiates the RCA reaction along the circular probe, syntheses macro-molecular mass products through repeated triggering sequences, triggers the CHA reaction to produce a large number of H1-H2 structures, which causes FAM to move away from BHQ-1 and recover its fluorescence signal. The fluorescence signal from FAM at 520 nm was collected as the signal output of aptasensor in this work. With high amplification efficiency of RCA and CHA of the fluorescence sensor, resulting in a low LOD value of 2.95 pg mL-1(S/N = 3). SIGNIFICANCE: The successful establishment of the sensor designed in this work shows that the cascade amplification reaction is perfectly applied in the fluorescent aptamer sensor, and the signal amplification through the reaction between DNA strands is a simple and efficient method. In addition, it's also important to remember that the aptasensor can detect other targets only by changing the sequence of the aptamer, without redesigning other DNA sequences in the reaction system.
Asunto(s)
Aflatoxina B1 , Aptámeros de Nucleótidos , Técnicas Biosensibles , Colorantes Fluorescentes , Técnicas de Amplificación de Ácido Nucleico , Aflatoxina B1/análisis , Aflatoxina B1/química , Aptámeros de Nucleótidos/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas Biosensibles/métodos , Colorantes Fluorescentes/química , Límite de Detección , Espectrometría de Fluorescencia , Contaminación de Alimentos/análisis , CatálisisRESUMEN
BACKGROUND: Aflatoxin B1 (AFB1), is a potent hepatic carcinogen which causes cancer by inducing DNA changes in the liver cells. Variety of methods have been developed for detection of AFB1 which are based on single mode detection strategy. Fabrication of novel platform which are compatible for multimodal detection of AFB1 provide robust performance for reliable detection of AFB1. In this study, we aimed to develop a robust biosensing platform that combines electrochemical and fluorescence techniques for the sensitive and specific detection of Aflatoxin B1. RESULTS: The sensing platform includes the magnetic core-shell Fe3O4@AuNPs and zeolitic imidazolate framework-8 (ZIF-8). In electrochemical mode, the applied voltametric approach was used through functionalization of glassy carbon electrode and exhibited a linear range between 0.5 and 10000 pg mL-1 with LOD of 0.32 pg mL-1. Fluorescence analysis was based on the FRET on/off status of FAM-functionalized aptamer deposited on the same platform. The FAM emission recovered by the addition of AFB1 concentration in the range of 6-60 fg mL-1 with the LOD of 0.20 fg mL-1. The real sample analysis demonstrated satisfactory relative recoveries in the range of 92.81-105.32 % and 91.66-106.66 % using the electrochemical and fluorescence methods, respectively, and its reliability was confirmed by the HPLC technique. SIGNIFICANCE: The experimental results affirm that the proposed aptasensor serves as a sensitive, efficient, and precise platform for monitoring AFB1 in both electrochemical and fluorescence detection approaches. Proposed strategy showed efficient selectivity among different analytes and was reproducible. Furthermore, the applicability of biosensor was confirmed in food and biological samples.
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Aflatoxina B1 , Técnicas Biosensibles , Técnicas Electroquímicas , Oro , Aflatoxina B1/análisis , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Oro/química , Aptámeros de Nucleótidos/química , Nanopartículas del Metal/química , Límite de Detección , Espectrometría de Fluorescencia , Estructuras Metalorgánicas/química , Fluorescencia , Zeolitas/químicaRESUMEN
Aspergillus flavus, the primary mold that causes food spoilage, poses significant health and economic problems worldwide. Eliminating A. flavus growth is essential to ensure the safety of agricultural products, and extracellular compounds (ECCs) produced by Bacillus spp. have been demonstrated to inhibit the growth of this pathogen. In this study, we aimed to identify microorganisms efficient at inhibiting A. flavus growth and degrading aflatoxin B1. We isolated microorganisms from soil samples using a culture medium containing coumarin (CM medium) as the sole carbon source. Of the 498 isolates grown on CM medium, only 132 bacterial strains were capable of inhibiting A. flavus growth. Isolate 3BS12-4, identified as Bacillus siamensis, exhibited the highest antifungal activity with an inhibition ratio of 43.10%, and was therefore selected for further studies. The inhibition of A. flavus by isolate 3BS12-4 was predominantly attributed to ECCs, with a minimum inhibitory concentration and minimum fungicidal concentration of 0.512 g/ml. SEM analysis revealed that the ECCs disrupted the mycelium of A. flavus. The hydrolytic enzyme activity of the ECCs was assessed by protease, ß-1,3-glucanase, and chitinase activity. Our results demonstrate a remarkable 96.11% aflatoxin B1 degradation mediated by ECCs produced by isolate 3BS12-4. Furthermore, treatment with these compounds resulted in a significant 97.93% inhibition of A. flavus growth on peanut seeds. These findings collectively present B. siamensis 3BS12-4 as a promising tool for developing environmentally friendly products to manage aflatoxin-producing fungi and contribute to the enhancement of agricultural product safety and food security.
Asunto(s)
Aflatoxina B1 , Antifúngicos , Aspergillus flavus , Bacillus , Agentes de Control Biológico , Microbiología del Suelo , Aspergillus flavus/efectos de los fármacos , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/metabolismo , Bacillus/metabolismo , Bacillus/efectos de los fármacos , Aflatoxina B1/metabolismo , Aflatoxina B1/biosíntesis , Agentes de Control Biológico/farmacología , Antifúngicos/farmacología , Pruebas de Sensibilidad Microbiana , Medios de Cultivo/química , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrolloRESUMEN
Co-contamination of multiple mycotoxins produces synergistic toxic effects, leading to more serious hazards. Therefore, the simple, rapid and accurate simultaneous detection of multiple mycotoxins is crucial. Herein, a three-channel aptamer-based lateral flow assay (Apt-LFA) was established for the detection of aflatoxin M1 (AFM1), aflatoxin B1 (AFB1) and ochratoxin A (OTA). The multi-channel Apt-LFA utilized goldiridium nanozyme to catalyze the chromogenic substrate, which effectively achieved signal amplification. Moreover, the positions and lengths of the complementary sequences were screened by changes in fluorescence intensity. After grayscale analysis, the semi-quantitative results showed that the detection limits of AFM1, AFB1 and OTA were 0.39 ng/mL, 0.36 ng/mL and 0.82 ng/mL. The recoveries of the multiplexed competitive sensors in complex matrices of real samples were 93.33%-97.01%, 95.72%-102.67%, and 106.88%-109.33%, respectively. In conclusion, the assembly principle of the three-channel Apt-LFA is simple, which can provide a new idea for the simultaneous detection of small molecule targets.