Patulin removal from apple juice using a novel cysteine-functionalized metal-organic framework adsorbent

Optimization of Seleno-chitosan-phytic acid nanocomplex for efficient removal of patulin from apple juice

A novel and effective adsorbent known as Seleno-chitosan-phytic acid nanocomplex (Se-CS-PA) has been developed specifically for efficiently removing patulin (PAT) from a simulated juice solution. The synthesis of Se-CS-PA nanocomplex was confirmed through Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-Ray (EDX) analyses. Response surface methodology (RSM) was employed using central composite design (CCD) to examine the impact of four independent variables (PA concentration, amount of nano-complex, duration of interaction between PAT and nano-complex, and initial concentration of PAT) on the removal of PAT. PA concentration of 0.1 % with 2.1 g Se-CS-PA nanocomplex according to RSM polynomial equation and apple juice with 25 μg.L-1 PAT yielded a remarkable adsorption rate of 94.23 % and 87.52 % respectively after 7 h. The process of PAT adsorption was explained using the pseudo-first-order model (R2 = 0.8858) for the kinetic model and the Freundlich isotherm (R2 = 0.9988) for the isotherm model.

In-situ growth of metal-organic frameworks on cellulose nanofiber aerogels for rapid adsorption of heterocyclic aromatic amines

Heterocyclic aromatic amines (HAAs) are the main carcinogens produced during thermal processing of protein-rich foods. In this paper, a composite aerogel (TOCNFCa) with a stabilized dual-network structure was prepared via a template for the in-situ synthesis of UiO-66 on cellulose for the adsorption of HAAs in food. The dual-network structure of TOCNFCa provides the composite aerogel with excellent wet strength, maintaining excellent compressive properties. With the in-situ grown UiO-66 content up to 71.89 wt%, the hierarchical porosity endowed TOCNFCa@UiO-66 with the ability to rapidly adsorb HAAs molecules with high capacity (1.44-5.82 μmol/g). Based on excellent thermal stability, adsorption capacity and anti-interference, TOCNFCa@UiO-66 achieved satisfactory recoveries of HAAs in the boiled marinade, which is faster and more economical than the conventional SPE method. Moreover, TOCNFCa@UiO-66 could maintain 84.55 % of the initial adsorption capacity after 5 times of reuse.

Infiltration of porcine pancreatic lipase into magnetic hierarchical mesoporous UiO-66-NH2 metal-organic frameworks for efficient detoxification of patulin from apple juice

Patulin (PAT) is a mycotoxin known to globally contaminate fruits. The economic losses and health hazards caused by PAT desires a safe and efficient strategy for detoxifying PAT. Here, a magnetic core-shell hierarchical mesoporous metal-organic framework (Fe3O4@HMUiO-66-NH2) was synthesized via a salt-assisted nanoemulsion guided assembly method. This mesoporous structure (centered at 4.25 nm) allowed porcine pancreatic lipase (PPL) to infiltrate into the MOF shell at an immobilized amount of 255 mg/g, providing protection for PPL and enabling rapid separation and recovery. Compared with free PPL, PPL/Fe3O4@HMUiO-66-NH2 at 70 °C possessed 4.7 folds improved thermal stability in terms of half-life. The detoxification rates of immobilized enzyme for PAT in neutral water, acidic water, and apple juice were 99.6%, 60.9%, and 52.6%, respectively. Moreover, the so designed PPL/Fe3O4@HMUiO-66-NH2 showed extraordinary storage stability, reusability, and biocompatibility. Crucially, the quality of apple juice did not change significantly after PPL/Fe3O4@HMUiO-66-NH2 treatment, which facilitated its application in apple juice. The magnetic core-shell mesoporous structure along with the revealed mechanism of immobilized enzyme detoxification of PAT provide tremendous opportunity for designing a safe and efficient PAT detoxification method.

High-throughput detection and dietary exposure risk assessment of 44 mycotoxins in Mango, Litchi, Longan, and their products in South China

Mycotoxins exposure from food can trigger serious health hazards. This study aimed to establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous detection of 44 mycotoxins in fruits and their products, followed by dietary exposure risk assessment. The optimized UPLC-MS/MS method exhibited a good linear relationship with correlation coefficients ≥ 0.99041. The limits of detection (LOD) and the limits of quantification (LOQ) were within the range of 0.003 ∼ 0.700 μg/kg and 0.01 ∼ 2.00 μg/kg, respectively. The three fruits and their corresponding value-added products, with a total sampling size of 42, were subjected to analysis and detected with mycotoxins. Further dietary exposure risk assessment revealed that the hazard quotient (HQ) and hazard index (HI) of mycotoxins were 1.213 ∼ 60.032 % and 5.573 ∼ 93.750 %, indicating a low risk for Chinese consumers. However, we still need be cautious about 15-acetyl-deoxynivalenol (15-ADON), as it had 78.6 % occurrence among all samples. This work provides an accurate analysis strategy for 44 mycotoxins and contributes to mycotoxins supervision.

Aptamers dimerization inspired biomimetic clamp assay towards impedimetric SARS-CoV-2 antigen detection

Antigen-detecting rapid diagnostic testing (Ag-RDT) has contributed to containing the spread of SARS-CoV-2 variants of concern (VOCs). In this study, we proposed a biomimetic clamp assay for impedimetric SARS-CoV-2 nucleocapsid protein (Np) detection. The DNA biomimetic clamp (DNA-BC) is formed by a pair of Np aptamers connected via a T₂₀ spacer. The 5'- terminal of the DNA-BC is phosphate-modified and then anchored on the surface of the screen-printed gold electrode, which has been pre-coated with Au@UiO-66-NH₂. The integrated DNA-material sensing biochip is fabricated through the strong Zr-O-P bonds to form a clamp-type impedimetric aptasensor. It is demonstrated that the aptasensor could achieve Np detection in one step within 11 min and shows pronounced sensitivity with a detection limit of 0.31 pg mL^-1. Above all, the aptasensor displays great specificity and stability under physiological conditions as well as various water environments. It is a potentially promising strategy to exploit reliable Ag-RDT products to confront the ongoing epidemic.

Efficient and simultaneous removal of aflatoxin B1, B2, G1, G2, and zearalenone from vegetable oil by use of a metal-organic framework absorbent

Vegetable oils are usually cocontaminated with different mycotoxins, including aflatoxins and zearalenone, which cause significant food safety issues. Establishment of multitarget, high-efficiency, and low-cost adsorption methods are considered to be ideal solutions for mycotoxin removal in vegetable oils. In this study, we used metal-organic frameworks (MOFs) were used for the simultaneous removal of aflatoxins and zearalenone from vegetable oils. The results showed that MOF-235 simultaneously removed, within 30 min, more than 96.1% of aflatoxins and 83.3% of zearalenone from oils, and oils treated with MOF-235 exhibited di minimis cytotoxicity. Thus, synthesized MOF-235 exhibited sufficient efficacy to remove the targeted residues, as well as safety and reusability, which could be applied as a novel potential adsorbent in the removal of multiple mycotoxins from contaminated vegetable oils.

Current Review of Mycotoxin Biodegradation and Bioadsorption: Microorganisms, Mechanisms, and Main Important Applications

Mycotoxins are secondary metabolites produced by fungi. Food/feed contamination by mycotoxins is a great threat to food safety. The contamination can occur along the food chain and can cause many diseases in humans and animals, and it also can cause economic losses. Many detoxification methods, including physical, chemical, and biological techniques, have been established to eliminate mycotoxins in food/feed. The biological method, with mycotoxin detoxification by microorganisms, is reliable, efficient, less costly, and easy to use compared with physical and chemical ones. However, it is important to discover the metabolite's toxicity resulting from mycotoxin biodegradation. These compounds can be less or more toxic than the parent. On the other hand, mechanisms involved in a mycotoxin's biological control remain still unclear. Mostly, there is little information about the method used by microorganisms to control mycotoxins. Therefore, this article presents an overview of the most toxic mycotoxins and the different microorganisms that have a mycotoxin detoxification ability. At the same time, different screening methods for degradation compound elucidation are given. In addition, the review summarizes mechanisms of mycotoxin biodegradation and gives some applications.

Possible Reaction Mechanisms Involved in Degradation of Patulin by Heat-Assisted Cysteine under Highly Acidic Conditions

Patulin (PAT) is one of mycotoxins that usually contaminates apple juice, and it is not easily detoxified by cysteine (CYS) at room temperature due to the highly acidic conditions based on the Michael addition reaction. However, it could be effectively degraded by a heating treatment at 120 °C for 30 min in the presence of cysteine. In our study, a total of eight degradation products (DP A–H) were characterized and identified via liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) in a negative ion mode, and their structures and formulas were proposed based on their accurate mass data. The fragmentation patterns of PAT and its degradation products were obtained from the MS/MS analysis. Meanwhile, the possible reaction mechanisms involved in the degradation of PAT were established and explained for the first time. According to the relation between the structure and toxicity of PAT, it could be deduced that the toxic effects of PAT degradation products were potentially much less than those of PAT-self.

Colorimetric and ratiometric fluorescent dual-mode sensitive detection of Hg2+ based on UiO-66-NH2@Au composite

A colorimetric and ratiometric fluorescent dual-mode assay is constructed for sensitive and specific Hg²⁺ sensing based on UiO-66-NH₂ and Au composite (UiO-66-NH₂@Au). The addition of Hg²⁺ stimulates the peroxidase-like activity of UiO-66-NH₂@Au by the formation of Au-Hg amalgam, promoting the oxidizing of chromogenic substrate OPD to DAP with the aid of H₂O₂, which lead to the change of colorimetric and fluorescent signals. The absorbance of the sensing system at 450 nm is linear positive correlation with Hg²⁺ concentration of 30-1400 nM and the color of the solution under visible light shaded from light yellow to dark yellow. With the increase of Hg²⁺ concentration, the fluorescence signal at 570 nm (DAP) increased whereas that at 455 nm (intrinsic fluorescence of UiO-66-NH₂) decreased due to inner filter effect (IFE), the fluorescence intensity ratio (F₄₅₅/F₅₇₀) decreasing linearly with Log [Hg²⁺] over the range 60-1700 nM; the fluorescence emission of sensing system under UV excitation changed from blue to yellow, which can easily be discerned visually. This assay was successfully applied to the determination of Hg²⁺ in tap water and river water. The results indicate that the colorimetric and ratiometric fluorescent dual-mode assay based on UiO-66-NH₂@Au realized visual determination of Hg²⁺ rapidly and reliably, revealed application prospect in Hg²⁺ monitoring.

Application of Nanomaterials for Coping with Mycotoxin Contamination in Food Safety: From Detection to Control

Mycotoxins, which are toxic secondary metabolites produced by fungi, are harmful to humans. Mycotoxin-induced contamination has drawn attention worldwide. Consequently, the development of reliable and sensitive detection methods and high-efficiency control strategies for mycotoxins is important to safeguard food industry safety and public health. With the rapid development of nanotechnology, many novel nanomaterials that provide tremendous opportunities for greatly improving the detection and control performance of mycotoxins because of their unique properties have emerged. This review comprehensively summarizes recent trends in the application of nanomaterials for detecting mycotoxins (fluorescence, colorimetric, surface-enhanced Raman scattering, electrochemical, and point-of-care testing) and controlling mycotoxins (inhibition of fungal growth, mycotoxin absorption, and degradation). These detection methods possess the advantages of high sensitivity and selectivity, operational simplicity, and rapidity. With research attention on the control of mycotoxins and the gradual excavation of the properties of nanomaterials, nanomaterials are also employed for the inhibition of fungal growth, mycotoxin absorption, and mycotoxin degradation, and impressive controlling effects are obtained. This review is expected to provide the readers insight into this state-of-the-art area and a reference to design nanomaterials-based schemes for the detection and control of mycotoxins.

More than a Virulence Factor: Patulin Is a Non-Host-Specific Toxin that Inhibits Postharvest Phytopathogens and Requires Efflux for Penicillium Tolerance

Mycotoxin contamination is a leading cause of food spoilage and waste on a global scale. Patulin, a mycotoxin produced by Penicillium spp. during postharvest pome fruit decay, causes acute and chronic effects in humans, withstands pasteurization, and is not eliminated by fermentation. While much is known about the impact of patulin on human health, there are significant knowledge gaps concerning the effect of patulin during postharvest fruit-pathogen interactions. Application of patulin on six apple cultivars reproduced some blue mold symptoms that were cultivar-independent and dose-dependent. Identical symptoms were also observed in pear and mandarin orange. Six Penicillium isolates exposed to exogenous patulin exhibited delayed germination after 24 h, yet all produced viable colonies in 7 days. However, four common postharvest phytopathogenic fungi were completely inhibited by patulin during conidial germination and growth, suggesting the toxin is important for Penicillium to dominate the postharvest niche. Using clorgyline, a broad-spectrum efflux pump inhibitor, we demonstrated that efflux plays a role in Penicillium auto-resistance to patulin during conidial germination. The work presented here contributes new knowledge of patulin auto-resistance, its mode of action, and inhibitory role in fungal-fungal interactions. Our findings provide a solid foundation to develop toxin and decay mitigation approaches.

Solid-phase extraction techniques based on nanomaterials for mycotoxin analysis: An overview for food and agricultural products

Mycotoxin contamination is a globally concerned problem for food and agricultural products since it may directly or indirectly induce severe threats to human health. Sensitive and selective screening is an efficient strategy to prevent or reduce human and animal exposure to mycotoxins. However, enormous challenges exist in the determination of mycotoxins, arising from complex sample matrices, trace-level analytes, and the co-occurrence of diverse mycotoxins. Appropriate sample preparation is essential to isolate, purify, and enrich mycotoxins from complicated matrices, thus decreasing sample matrix effects and lowering detection limits. With the cross-disciplinary development, new solid-phase extraction strategies have been exploited and integrated with nanotechnology to meet the challenges of mycotoxin analysis. This review summarizes the advance and progress of solid-phase extraction techniques as the methodological solutions for mycotoxin analysis. Emphases are paid on nanomaterials fabricated as trapping media of SPE techniques, including carbonaceous nanoparticles, metal/metal oxide-based nanoparticles, and nanoporous materials. Advantages and limitations are discussed, along with the potential prospects. This article is protected by copyright. All rights reserved.

Removal of patulin by thiol-compounds: A review

Patulin (PAT) is a toxic mycotoxin usually contaminated apple juices, which leads to a serious food safety issue in the world. Thiol-compounds are a class of compounds containing the thiol (-SH) group themselves or obtained the -SH group by physical or chemical modification. They have the ability to efficiently remove patulin in apple juices with manifested negligible effects on juice quality. This review investigates the latest development in the removal of patulin using thiol-compounds, including the removal efficiencies and mechanisms of patulin, the factors influencing the removal efficiency of patulin, as well as the toxicities of thiol-compounds and safety of juices after detoxification. This review shows that thiol-compounds are promising materials for the removal or degradation of patulin in the contaminated juices.

Amyloid Fibril Templated MOF Aerogels for Water Purification

Design and fabrication of versatile adsorbents for universal water purification following green chemistry principles remain challenging. Here, it is shown that amyloid fibrils from protein waste can be used as a functional scaffold for metal organic framework (MOF) biomimetic mineralization. The resulting amyloid fibrils/ZIF-8 hybrid aerogels can effectively remove nine different heavy metal ions from water due to their hierarchical porous structure. Importantly, amyloid fibrils/ZIF-8 hybrid aerogels can efficiently remove Hg²⁺ and Pb²⁺ from water over five consecutive adsorption-regeneration cycles. Furthermore, a dual removal pathway of adsorption and catalytic degradation is observed in the synthetic dyes, indicating that the aerogel preserves its porous nature and maintains the integrity of versatile functional ligands within ZIF-8. Finally, it is shown that these hybrid aerogels can also perform successfully in oil-water separation. Considering the facile synthesis procedure, high removal efficiency, affordable cost, and regeneration possibilities, the amyloid fibrils/ZIF-8 hybrid aerogel stands as an ideal candidate for addressing open challenges in wastewater treatment and water purification.

Remarkable Uptake of Deoxynivalenol in Stable Metal-Organic Frameworks

Deoxynivalenol (DON), which is known as one of the most harmful mycotoxins, has contaminated food and feed and attracted concerns worldwide. However, the effective adsorptive removal of DON to ensure food safety still is a challenge, which is ascribed to the poor planarity and larger steric hindrance of DON molecules. Here, a new Zr(IV)-based metal-organic framework, entitled BUT-16 with one-dimensional channels and N-atom-decorated pore surface, is designed, prepared, and utilized for the adsorptive removal of DON. It exhibits excellent adsorption ability with an adsorption capacity of 46 mg/g higher than all reported adsorbents until now and a rapid adsorption rate of 0.031 g mg^-1 min^-1. DFT calculation and X-ray photoelectron spectroscopy results of the guest-loaded phase suggest that the record-breaking adsorption could be due to the cooperation of hydrogen bonding and Zr···O interaction between DON molecules and BUT-16 host. Most importantly, BUT-16 can effectively adsorb and remove DON in the simulated gastric fluid, but DON adsorbed on BUT-16 is hardly desorbed in the simulated intestinal fluid. The results demonstrate that BUT-16 has great promising application for the control of DON in foods and feeds.

Factors influencing the removal of patulin by cysteine

The removal of patulin in phosphoric acid buffer solution by cysteine was investigated. Cysteine could effectively decrease the patulin concentration at high acidic condition (pH 3.0-5.0) with the help of high temperature greater than 90 °C. Three removal mechanisms of patulin by cysteine under high acidic and high temperature conditions were deduced. Reaction temperature, pH of reactive media, molar ratio between cysteine and patulin, and reaction time were all the obvious factors influencing the removal efficiency of patulin, and the increase of any one factor could significantly improve the removal efficiency of patulin. The removal process of patulin could be simulated by the zero-order kinetic model, logarithmic model, and pseudo-first-order kinetic model, respectively, and the corresponding correlation coefficients (R²) were all greater than 0.90. Presently, this method can only be applied for the removal of patulin in contaminated water from washing fruits in juice processing industry due to the high treatment temperature more than 120 °C and the long detoxification time greater than 1 h.

Thermal Stability and Degradation Kinetics of Patulin in Highly Acidic Conditions: Impact of Cysteine

The thermal stability and degradation kinetics of patulin (PAT, 10 μmol/L) in pH 3.5 of phosphoric-citric acid buffer solutions in the absence and presence of cysteine (CYS, 30 μmol/L) were investigated at temperatures ranging from 90 to 150 °C. The zero-, first-, and second-order models and the Weibull model were used to fit the degradation process of patulin. Both the first-order kinetic model and Weibull model better described the degradation of patulin in the presence of cysteine while it was complexed to simulate them in the absence of cysteine with various models at different temperatures based on the correlation coefficients (R² > 0.90). At the same reaction time, cysteine and temperature significantly affected the degradation efficiency of patulin in highly acidic conditions (p < 0.01). The rate constants (k_T) for patulin degradation with cysteine (0.0036-0.3200 μg/L·min) were far more than those of treatments without cysteine (0.0012-0.1614 μg/L·min), and the activation energy (E_a = 43.89 kJ/mol) was far less than that of treatment without cysteine (61.74 kJ/mol). Increasing temperature could obviously improve the degradation efficiency of patulin, regardless of the presence of cysteine. Thus, both cysteine and high temperature decreased the stability of patulin in highly acidic conditions and improved its degradation efficiency, which could be applied to guide the detoxification of patulin by cysteine in the juice processing industry.

Effects of Pretreatments on Patulin Removal from Apple Juices Using Lactobacilli: Binding Stability in Simulated Gastrointestinal Condition and Modeling

Recently, researchers have reported the presence of patulin as a mycotoxin in commercial apple products, especially apple juices. The aim of this study was to assess adsorption of patulin from artificially contaminated apple juice using two lactic acid bacteria (LAB) strains of Lactobacillus acidophilus ATCC 4356 and Lactobacillus plantarum ATCC 8014. Furthermore, effects of five physical and chemical pretreatments on the patulin adsorption were investigated. Results demonstrated that patulin adsorption abilities of both strains increased with NaOH pretreatment but decreased after autoclaving. The NaOH-treated L. plantarum ATCC 8014 showed the best removal rate (59.74%) after 48 h of refrigerated storage, compared with the NaOH-treated L. acidophilus ATCC 4356 (52.36%). Moreover, stability of the LAB-patulin complex was assessed in simulated gastrointestinal tract conditions and a low quantity of patulin was released into the solution. The patulin adsorption process by NaOH-treated L. plantarum ATCC 8014 followed Freundlich isotherm model and pseudo-second-order kinetic model. Fourier transform infrared spectroscopy showed that polysaccharide and protein components of the L. plantarum ATCC 8014 cell wall played key roles in patulin adsorption. The major functional groups of the cell wall that were involved in adsorbing patulin included -OH/-NH, -CH₂, C=O, and C-O groups. The current results suggest that NaOH-treated L. plantarum ATCC 8014 cells include the potential to detoxify patulin-contaminated apple juices.

Protective effect against d-gal-induced aging mice and components of polypeptides and polyphenols in defatted walnut kernel during simulated gastrointestinal digestion

Defatted walnut kernel with pellicle (WKP) is an industrial byproduct during walnut oil extraction, which is rich in protein and polyphenols. WKP was hydrolyzed by simulated gastrointestinal digestion to obtain WKP hydrolysates (WKPHs). Results showed the protein recovery and hydrolysis degree of WKPH were 82.15 and 10.36%. The total phenol contents in WKP and WKPH were 4.90 and 40.70 mg gallic acid equivalent/g, respectively. The antiaging activity of WKPH was evaluated using a d-gal-induced aging mouse model. Results showed that WKPHs could recover the activities of SOD and T-AOC and the content of MDA in tissues and serum of the aging mice. The histological morphology of liver and kidney sections and the immunohistochemistry of TNF-α, IL-1β, and IL-6 in liver were observed. WKPH could effectively protect the tissue structure of the liver and kidney and reduce the inflammatory expression of liver in aging mice. The polypeptides and polyphenols in WKPH were further analyzed. Fifty polypeptides were identified and 12 of these peptides had Leu-Arg at the C-terminal. Forty-two polyphenols were detected, and most phenolic compounds belonged to ellagitannins. This study provided a theoretical basis for the improved processing and high-value utilization of walnut byproducts. PRACTICAL APPLICATION: Defatted walnut kernel with pellicle was hydrolyzed by simulated gastrointestinal digestion to obtain its hydrolysates. The hydrolysates have good antiaging activity in vivo. Fifty polypeptides were identified and 12 of these peptides had Leu-Arg at the C-terminal. Forty-two polyphenols were detected, and most phenolic compounds belonged to ellagitannins. This study could provide a theoretical basis for high-value utilization of walnut byproducts.

Critical Assessment of Mycotoxins in Beverages and Their Control Measures

Mycotoxins are secondary metabolites of filamentous fungi that contaminate food products such as fruits, vegetables, cereals, beverages, and other agricultural commodities. Their occurrence in the food chain, especially in beverages, can pose a serious risk to human health, due to their toxicity, even at low concentrations. Mycotoxins, such as aflatoxins (AFs), ochratoxin A (OTA), patulin (PAT), fumonisins (FBs), trichothecenes (TCs), zearalenone (ZEN), and the alternaria toxins including alternariol, altenuene, and alternariol methyl ether have largely been identified in fruits and their derived products, such as beverages and drinks. The presence of mycotoxins in beverages is of high concern in some cases due to their levels being higher than the limits set by regulations. This review aims to summarize the toxicity of the major mycotoxins that occur in beverages, the methods available for their detection and quantification, and the strategies for their control. In addition, some novel techniques for controlling mycotoxins in the postharvest stage are highlighted.

Hydrophilic carboxyl supported immobilization of UiO-66 for novel bar sorptive extraction of non-steroidal anti-inflammatory drugs in food samples

Herein, the preparation of UiO-66 on frosted glass rod (FGR) was proposed through the coordination interaction of Zr-OH groups and carboxyl sites on FGR. The relative standard deviations (RSDs) of intra-batch and inter-batch were below 8.0% (n = 7). UiO-66-modified FGR (UiO-66@FGR) was applied to the extraction and monitoring of five non-steroidal anti-inflammatory drugs (NSAIDs) by coupling to novel bar sorptive extraction (BSE) with ultra-high performance liquid chromatography (UPLC). Sample volume, stirring rate, extraction time, sample pH value, desorption solvent, and desorption time were investigated. NSAIDs (ketoprofen, flurbiprofen, ibuprofen, naproxen, and diclofenac sodium) were determined at a low limit of detection (0.92 ng/mL) over a wide linear range (10-1500 ng/mL). The developed method was used to analyze NSAIDs in sheep muscle, chicken wing, and milk with recoveries of 80.8%-117.2%, RSDs < 6.5%. Fabricated UiO-66@FGR exhibited excellent reproducibility, stability, and good adsorption property towards NSAIDs in food samples.

Metal-organic frameworks for food applications: A review

Metal-organic frameworks (MOFs) are high surface-to-volume ratio crystalline hybrid porous coordination materials composed of metal ions as nodes and organic linkers. The goal of this paper was to provide an updated and comprehensive state-of-the-art review of MOFs for different food applications such as active food contact materials, antimicrobial nanocarriers, controlled release nanosystems for active compounds, nanofillers for food packaging materials, food nanoreactors, food substance nanosensors, stabilizers and immobilizers for active compounds and enzymes, and extractors of food contaminants. Extraction and sensing of several food contaminants have been the main food applications of MOFs. The other applications listed above require further investigation, as they are at an early stage. However, interesting results are being reported for these other fields. Finally, an important limitation of MOFs has been the use of non-renewable feedstocks for their synthesis, but this has recently been solved through the manufacture and use of γ-cyclodextrin-based MOFs.

Patulin and Trichothecene: characteristics, occurrence, toxic effects and detection capabilities via clinical, analytical and nanostructured electrochemical sensing/biosensing assays in foodstuffs

Patulin and Trichothecene as the main groups of mycotoxins in significant quantities can cause health risks from allergic reactions to death on both humans and animals. Accordingly, rapid and highly sensitive determination of these toxics agents is of great importance. This review starts with a comprehensive outlook regarding the characteristics, occurrence and toxic effects of Patulin and Trichothecene. In the following, numerous clinical and analytical approaches have been extensively discussed. The main emphasis of this review is placed on the utilization of novel nanomaterial based electrochemical sensing/biosensing tools for highly sensitive determination of Patulin and Trichothecene. Furthermore, a detailed and comprehensive comparison has been performed between clinical, analytical and sensing methods. Subsequently, the nanomaterial based electrochemical sensing platforms have been approved as reliable tools for on-site analysis of Patulin and Trichothecene in food processing and manufacturing industries. Different nanomaterials in improving the performance of detecting assays were investigated and have various benefits toward clinical and analytical methods. This paper would address the limitations in the current developments as well as the future challenges involved in the successful construction of sensing approaches with the functionalized nanomaterials and also allow exploring into core-research works regarding this area.

Design of turn-on luminescent sensor based on nanostructured molecularly imprinted polymer-coated zirconium metal-organic framework for selective detection of chloramphenicol residues in milk and honey

Herein, an optical sensor based on nanostructured molecularly imprinted polymer (MIP) coated on a luminescent zirconium metal-organic framework (MIP/Zr-LMOF) is introduced, and its performance is investigated for the fluorescent determination of chloramphenicol (CAP) antibiotic residues in milk and honey. To fabricate the sensor, the surface of Zr-LMOF is modified with MIP in the presence of CAP template, resulting in the introduction of recognition sites for antibiotic molecules. The porous structure of Zr-LMOF with specific binding sites for CAP recognition benefiting from coated MIP leads to selective and sensitive detection of antibiotic. The probe yields a linear range for detection of CAP in trace concentrations (0.16-161.56 µg.L^-1) and provides a detection limit of 0.013 µg.L^-1. Acceptable recoveries are achieved for antibiotic in real samples, which are consistent with that obtained from liquid chromatography-tandem mass spectrometry (LC-MS/MS), confirm the favorable performance of sensor for accurate determination of CAP in practical applications.

Advances in Colorimetric Strategies for Mycotoxins Detection: Toward Rapid Industrial Monitoring

Mycotoxins contamination is a global public health concern. Therefore, highly sensitive and selective techniques are needed for their on-site monitoring. Several approaches are conceivable for mycotoxins analysis, among which colorimetric methods are the most attractive for commercialization purposes thanks to their visual read-out, easy operation, cost-effectiveness, and rapid response. This review covers the latest achievements in the last five years for the development of colorimetric methods specific to mycotoxins analysis, with a particular emphasis on their potential for large-scale applications in food industries. Gathering all types of (bio)receptors, main colorimetric methods are critically discussed, including enzyme-linked assays, lateral flow-assays, microfluidic devices, and homogenous in-solution strategies. This special focus on colorimetry as a versatile transduction method for mycotoxins analysis is comprehensively reviewed for the first time.

Prevention and detoxification of patulin in apple and its products: A review

Patulin-producing fungi pose an unavoidable problem for apple and its product quality, thereby threatening human and/or animal health. Studies on controlling the patulin-producing fungal growth and patulin contamination in apple and its products by physical methods, chemical fungicides, and biological methods have been performed for decades, but patulin contamination has not been addressed. Here, the important of studying regulation mechanism of patulin production in apple at the protein expression and metabolism levels is proposed, which will facilitate the development of controlling patulin production by using physical, chemical, and biological methods. Furthermore, the advantages or disadvantages and effects or mechanisms of using physical, chemical, biological methods to control the decay caused by Penicillium expansum and to remove patulin in food was discussed. The development of physical methods to remove patulin depends on the development of special equipment. Chemical methods are economical and efficient, if we have ensured that there are no unknown reactions or toxic by-products by using these chemicals. The biological method not only effectively controls the decay caused by Penicillium espansum, but also removes the toxins that already exist in the food. Degradation of patulin by microorganisms or biodegradation enzymes is an efficient and promising method to remove patulin in food if the microorganisms used and the degradation products are completely non-toxic.

Zirconium(Ⅳ)-based metal-organic framework for determination of imidacloprid and thiamethoxam pesticides from fruits by UPLC-MS/MS

Zirconium(Ⅳ)-based metal-organic framework (MOF)-UiO-66-NH₂ was fabricated to adsorb the imidacloprid and thiamethoxam in fruit samples before analysis using UPLC-MS/MS. The UiO-66-NH₂ was confirmed by SEM, FTIR, and XRD. Key experimental parameters were investigated by response surface methodology (RSM). The desirability recovery of imidacloprid was 94.52% under optimum conditions (mount of adsorbent = 52.48 mg, volume of eluent = 5.18 mL, pH = 9, extraction time = 15 min). The desirability recovery of thiamethoxam was 93.57% under optimum conditions (mount of adsorbent = 50.58 mg, volume of eluent = 2.6 mL, pH = 5.65, extraction time = 11.94 min). Under the optimal conditions, the actual recovery of imidacloprid and thiamethoxam was 92.39% and 94.37%, respectively. Besides, the method was applied successfully to detect imidacloprid and thiamethoxam in different fruit samples. The results demonstrated that the UiO-66-NH₂ is an excellent adsorbent for the extraction imidacloprid and thiamethoxam from fruit samples.

A novel electrochemical aptasensor for the sensitive detection of kanamycin based on UiO-66-NH2/MCA/MWCNT@rGONR nanocomposites

In this work, we designed and synthesized a nanocomposite comprising an amine-functionalized metal organic framework (UiO-66-NH₂), a multiwalled carbon nanotube@reduced graphene oxide nanoribbon (MWCNT@rGONR) and a covalent organic framework (COF) synthesized using melamine and cyanuric acidmonomers via polycondensation (represented by MCA). The UiO-66-NH₂/MCA/MWCNT@rGONR nanocomposite was used as a sensitive platform for an electrochemical aptasensor to detect kanamycin (kana). Owing to the rich chemical functionality, amino-rich structure and excellent electrochemical activity, the cDNA strands with terminal amino groups can not only anchor over the UiO-66-NH₂/MCA/MWCNT@rGONR surface but also penetrate into the interior of porous UiO-66-NH₂/MCA/MWCNT@rGONR networks. The characterization of the UiO-66-NH₂/MCA/MWCNT@rGONR nanocomposite was performed by scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD). Furthermore, cyclic voltammetry (CV) and square wave voltammetry (SWV) were employed for the electrochemical performance study of this biosensor. The results indicated that the UiO-66-NH₂/MCA/MWCNT@rGONR nanocomposite exhibited high bioaffinity toward the aptamer and the lowest limit of detection at 13 nM (S/N = 3) within a linearity of the kana concentration of 25-900 nM. In addition, it possessed great repeatability, stability and selectivity and obtained satisfactory recovery results in the real analysis of fish meat and milk, indicating the great potential for analytical measurements in food safety.

Recent Advances in Affinity MOF-Based Sorbents with Sample Preparation Purposes

This review summarizes the recent advances concerning metal-organic frameworks (MOFs) modified with several biomolecules (e.g., amino acids, nucleobases, proteins, antibodies, aptamers, etc.) as ligands to prepare affinity-based sorbents for application in the sample preparation field. The preparation and incorporation strategies of these MOF-based affinity materials were described. Additionally, the different types of ligands that can be employed for the synthesis of these biocomposites and their application as sorbents for the selective extraction of molecules and clean-up of complex real samples is reported. The most important features of the developed biocomposites will be discussed throughout the text in different sections, and several examples will be also commented on in detail.

Aerogel doped by sulfur-functionalized graphene oxide with convenient separability for efficient patulin removal from apple juice

Patulin (PAT) contaminant causes severe food safety issue throughout apple industry. Although adsorption is the feasible approach to remove PAT, the limited adsorption capacity and separation difficulty of most adsorbent is the major drawback that remains to be overcome. Here GO-SH doped aerogel was prepared and used for removal PAT from apple juice. The intrinsic porous of the aerogel and abundant active sites including -COOH, -NH₂ and -SH offered the PAT adsorption capacity of 24.75 μg/mg that superior to most reported adsorbents. Furthermore, it could reduce 89 ± 1.23% PAT in real apple juice without juice quality deterioration and cytotoxicity. Importantly, the aerogel with good mechanical strength and structure stability could endure the complex juice solution so that there was no any residue after convenient separation of the aerogel, which proved that the proposed aerogel was a promising adsorbent to be applied to apple juice industry for PAT removal.

Recent trends in detecting, controlling, and detoxifying of patulin mycotoxin using biotechnology methods

Patulin (PAT) is a mycotoxin that can contaminate many foods and especially fruits and fruit-based products. Therefore, accurate and effective testing is necessary to enable producers to comply with regulations and promote food safety. Traditional approaches involving the use of chemical compounds or physical treatments in food have provided practical methods that have been used to date. However, growing concerns about environmental and health problems associated with these approaches call for new alternatives. In contrast, recent advances in biotechnology have revolutionized the understanding of living organisms and brought more effective biological tools. This review, therefore, focuses on the study of biotechnology approaches for the detection, control, and mitigation of PAT in food. Future aspects of biotechnology development to overcome the food safety problem posed by PAT were also examined. We find that biotechnology advances offer novel, more effective, and environmental friendly approaches for the control and elimination of PAT in food compared to traditional methods. Biosensors represent the future of PAT detection and use biological tools such as aptamer, enzyme, and antibody. PAT prevention strategies include microbial biocontrol, the use of antifungal biomolecules, and the use of microorganisms in combination with antifungal molecules. PAT detoxification aims at the breakdown and removal of PAT in food by using enzymes, microorganisms, and various adsorbent biopolymers. Finally, biotechnology advances will be dependent on the understanding of fundamental biology of living organisms regarding PAT synthesis and resistance mechanisms.

Optimization of grape juice deacidification using mixture of adsorbents: A case study of Pekmez

Grape syrup (Pekmez or Dooshab) is one of the nutritious products developed through grape processing. One of the main challenges in the industrial manufacture of this product is the utilization of traditional pekmez earth for tartaric acid adsorption. The objectives of this study were to investigate the effect of calcium carbonate, nano-silica, alumina, and activated carbon as adsorbents and also contact time in grape juice deacidification, and to determine the effects of these adsorbents on the physicochemical properties of grape juice by using the Box-Behnken statistical design. By applying different amounts of these adsorbents in grape juice, the magnitude of acidity decrement and the physicochemical properties such as acidity, pH, transmittance, the amount of reducing sugars, formalin index, and adsorption efficiency were investigated. Data analysis showed that different mixtures of adsorbents at different concentrations had significant effects on acidity and pH of the samples but no effects on the level of reducing sugars and formalin index were observed (p > .05). According to the results, the adsorption capacity with the highest calcium carbonate content (0.7 g/100 ml) was about 88%; the maximum acidity decrements of up to 92% were achieved using the treatments containing calcium carbonate, nano-silica, and activated carbon, while alumina failed to affect the acidity of the samples. Optimum conditions were obtained in 1.27, 0.21, 0.7, and 0.07 g/100 ml alumina, nano-silica, calcium carbonate, and activated carbon, respectively, resulting pH 4.3 and acidity 0.37% in grape syrup.

Plasmonic nanoparticles on metal-organic framework: A versatile SERS platform for adsorptive detection of new coccine and orange II dyes in food

Synthetic dyes have been widely applied to food processing, but abuse of colourants in food may pose risks to human health. To analyze new coccine (NC) and orange II (OII) in food, a versatile surface-enhanced Raman scattering (SERS) platform was proposed. A metal-organic framework (MOF, UiO-66(NH₂)) with octahedral crystal structure was synthesized and gold nanoparticles were grown on the MOF surface to fabricate UiO-66(NH₂)@Au versatile SERS platform. The UiO-66(NH₂)@Au displayed much better SERS performance than gold nanoparticles with high R² of 0.9684 for NC and 0.9912 for OII and low LOD of 0.4015 mg/L for NC and 0.0546 mg/L for OII. The recoveries of NC and OII in Mirinda soft drink and paprika ranged from 82.92 to 109.63%. This study provided a sensitive and rapid method for determination of NC and OII through UiO-66(NH₂)@Au, and the proposed SERS platform revealed great potential for analyzing synthetic colourants in food samples.

Thiol-functionalized inactivated yeast embedded in agar aerogel for highly efficient adsorption of patulin in apple juice

The issue of patulin (PAT) contamination in apple juice has attracted widespread concern. Recently, inactivated yeast based biosorbents have shown great advantages in the removal of toxic contaminants. However, the traditional yeast adsorbents have disadvantages of a limited adsorption capacity in juice and separation difficulty. In the present work, five chemical thiol-functionalization methods were used to increase the PAT adsorption efficiency of yeast cells in apple juice. Thereinto, glutaraldehyde cross-linking increased the thiol (-SH) content of yeast cells to 1.26 mmol g^-1 and improved the PAT adsorption capacity of inactivated yeast in apple juice by 150 times. The covalent bonding of -SH and PAT played an important role in the improvement of adsorption capacity. The as-prepared thiol-modification yeast (Y-SH(Gl)) was then embedded in the agar aerogel to obtain Y-SH(Gl)@Agar free of separation. PAT adsorption of Y-SH(Gl)@Agar was consistent with the Freundlich model and the pseudo-second-order kinetic model. Moreover, Y-SH(Gl)@Agar was competent for PAT removal in apple juice and manifested negligible effects on juice quality. Cytotoxicity investigation indicated its good biocompatibility and ignorable food safety risk, thereby demonstrating that Y-SH(Gl)@Agar may be a promising adsorbent material for the control of PAT contaminant in juice.