Effects of FB1 and HFB1 on Autonomous Exploratory and Spatial Memory and Learning Abilities in Mice.

Fumonisin B1 (FB1) is a representative form of fumonisin and is widely present in food and feed. Hydrolyzed fumonisin B1 (HFB1) emerges as a breakdown product of FB1, which is accompanied by FB1 alterations. While previous studies have primarily focused on the liver or kidney toxicity of FB1, with limited studies existing on its neurotoxicity and even fewer on the toxicity of HFB1, this study focuses on the neurotoxicity of FB1 and HFB1 exposure in mice investigated by the open field test, Morris water maze test, histopathological analysis, and nontargeted metabolomics. Further, the levels of oxidative stress-related indices, neurotransmitters, and sphingolipids in the brain were measured to analyze their correlation with behavioral outcomes. The results showed that both FB1 (5 mg/kg) and HFB1 (2.8 mg/kg) reduced autonomous exploratory behavior in mice, impaired spatial learning and memory, and caused mild abnormalities in the brain structure. Quantitative analysis further indicated that exposure to FB1 and HFB1 disrupted neurotransmitter homeostasis, exacerbated oxidative stress, and significantly increased the sphinganine/sphingosine (Sa/So) ratio. Moreover, HFB1 exhibited neurotoxic effects similar to those of FB1, emphasizing the need to pay attention to the neurotoxicity effect of HFB1. These findings underscore the importance of understanding the risks and potential neurological damage associated with FB1 and HFB1 exposure, highlighting the necessity for further research in this crucial field.

Effect of Baking Conditions and Glucose Addition on the Changes and Transformations between Fumonisins and their Covert Forms during Corn Crisp Processing.

This study investigated the impact of baking factors on fumonisin B (FB) levels in corn crisps using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results indicated that both free and total FBs decreased with an increase in baking time and temperature, while glucose addition facilitated this reduction. Total FBs reached the lowest value of 109.69 ng/g after 50 min of baking. Conversely, covert FBs increased with baking time but decreased with glucose addition at high temperatures. Additionally, the highest levels of hydrolyzed FBs (HFBs), N-(carboxymethyl) FB1, and N-(deoxy-d-fructos-1-yl) FB1 occurred 20 min before decomposing and were detected in corn crisps baked at 160 °C. Glucose addition accelerated the transformation between free and covert FBs. Furthermore, the inhibition of NCM FB1 accumulation was accompanied by the promotion of NDF FB1 accumulation during corn crisp processing. These findings provide insights into the effect of baking factors on FBs and suggest strategies for reducing FB contamination in corn crisps.

Metabolic pathway-based self-assembled Au@MXene liver microsome electrochemical biosensor for rapid screening of aflatoxin B1.

Cytochrome P450 enzymes (CYPs) catalyze the production of aflatoxin B1 (AFB1) metabolites, which play an important role in carcinogenesis. In this study, we report a simple electrochemical liver-microsome-based biosensor using a composite of gold nanoparticles adsorbed on MXene (Au@MXene) for rapid screening of AFB1. Rat liver microsomes (RLMs) were directly adsorbed on the Au@MXene nanocomposite. The high conductivity, large specific surface area, and good biocompatibility of the Au@MXene nanocomposite enabled the direct electron transfer between the RLMs and the electrode and maintained the biological activity of the enzyme in the RLMs to a large extent. The metabolic behavior of the RLM biosensor that was developed for the electrocatalyst of AFB1 to its hydroxylation metabolite aflatoxin M1 (AFM1) was confirmed. Based on the change in the electrical signal generated by this metabolic behavior, we established the relationship between AFB1 content and amperometric (I-t) current signal. When the AFB1 concentration ranged from 0.01 µM to 50 µM, the AFB1 concentration was linearly related to the electrical signal with a limit of detection of 2.8 nM. The results of the recovery experiments for corn samples showed that the recovery and accuracy of the sensor were consistent with the UPLC-MS/MS method.

Occurrence, transformation, and toxicity of fumonisins and their covert products during food processing.

Fumonisins comprise structurally related metabolites mainly produced by Fusarium verticillioides and Fusarium proliferatum. Contamination with fumonisins causes incalculable damage to the economy and poses a great risk to animal and human health. Fumonisins and their covert products are found in cereals and cereal products. Food processing significantly affects the degradation of toxins and the formation of covert toxins. However, studies on fumonisins and their covert mycotoxins remain inadequate. This review aims to summarize changes in fumonisins and the generation of covert fumonisins during processing. It also investigates the toxicity and determination methods of fumonisins and covert fumonisins, and elucidates the factors affecting fumonisins and their covert forms during processing. In addition to the metabolic production by plants and fungi, covert fumonisins are mainly produced by covalent or noncovalent binding, complexation, or physical entrapment of fumonisins with other substances. The toxicity of covert fumonisins is similar to that of free fumonisins and is a non-negligible hazard. Covert fumonisins are commonly found in food matrices, and methods to analyze them have yet to be improved. Food processing significantly affects the conversion of fumonisins to their covert toxins.

One-step time-resolved fluorescence microsphere immunochromatographic test strip for quantitative and simultaneous detection of DON and ZEN.

Deoxynivalenol (DON) and zearalenone (ZEN) are mycotoxins that contaminate a wide range of grains and crops. In this study, a one-step time-resolved single-channel immunochromatographic test strip based on europium ion polystyrene fluorescence microspheres was first developed for sensitive and quantitative detection of DON and ZEN. The concentration of the artificial antigen and the mass ratio of the monoclonal antibody to fluorescent microspheres for conjugation were optimized to simplify the sample addition process during immunochromatographic assay and improve the on-site detection efficiency. The limits of detection (LOD) of the single-channel immunochromatographic test strip for DON and ZEN detection were 0.17 and 0.54 µg/L, respectively. Meanwhile, the dual-channel immunochromatographic test strip was designed to simultaneously detect DON and ZEN, with LODs of 0.24 and 0.69 µg/L achieved for DON and ZEN, respectively. The developed test strips also yielded recovery results consistent with that obtained by LC-MS/MS for DON and ZEN detection in real samples of wheat and corn flour, confirming the practicability and reliability of the test strip. The developed immunochromatographic test strips realize quick and sensitive detection of DON and ZEN, exhibiting potential for broad applications in the point-of-care testing platform of multiple mycotoxins in agricultural products. Graphic abstract.

Effects of smoking or baking procedures during sausage processing on the formation of heterocyclic amines measured using UPLC-MS/MS.

We used an UPLC-MS/MS method to investigate the effects of smoking or baking on the formation of heterocyclic amines (HAs) in sausage processing. We used principal component analysis (PCA) to differentiate the chemical composition, pH and colour of the processed sausages. We detected and quantified eight types of HAs (PhIP, DMIP, Phe-P-1, IQ[4,5-b], 7,8-DiMeIQx, AαC, harman and norharman) in sausages, finding total HA concentrations as high as 422 ±â€¯17.5 ng/g. Higher smoking temperatures led to higher concentrations of total HA in smoked sausages (330 ±â€¯8.19 to 422 ±â€¯17.5 ng/g). On the contrary, higher baking temperatures created lower total HA concentrations in baked sausages (ranging from 139 ±â€¯9.83 to 306 ±â€¯0.92 ng/g). Our results demonstrated that HAs are produced even at low temperatures, which means that HAs should be controlled during sausage processing to minimise their formation.