Determination of trace patulin in apple-based food matrices

Validation and screening of patulin in apple beverages marketed in Morocco

Patulin is one of the mycotoxins frequently detected in apples and derivatives, representing a major food safety risk. This study aimed to validate a high-performance liquid chromatography (HPLC) method with an ultraviolet (UV) detector for patulin quantification and assess its occurrence in apple beverages marketed in Morocco. The validation parameters showed satisfactory results with adequate linearity (R > 0.997), a relative standard deviation below 2.5%, repeatability between 3.6 and 7.1%, reproducibility between 3.9 and 11.5%, a limit of quantification (LOQ) of 4 μg/L, and recoveries close to 100% for three levels. Analysis of 30 samples revealed patulin levels ranging from 0 to 16.36 μg/L, with 50% of samples showing negative levels. All positive results remained below the regulatory maximum limit of 50 μg/L. These findings affirm the efficacy of the HPLC proposed method in ensuring compliance with patulin regulations in apple beverages, underlining its importance in safeguarding food safety.

A fluorescence aptamer sensor utilizing WS2 nanosheets for sensitive detection of patulin: enhanced specificity and wide applicability

A tungsten disulfide (WS2) nanosheet-based aptamer sensor was developed to detect patulin (PAT). The 5'-end of the PAT aptamer was modified with a cyanine 3 (Cy3) fluorophore, which self-assembled on WS2 nanosheets. The interaction between the Cy3 fluorophore at the 5'-end of the PAT aptamer and the WS2 nanosheets resulted in reduced fluorescence (FL) intensity due to fluorescence resonance energy transfer (FRET). The introduction of PAT into this sensing system led to hybridization with the PAT aptamer, forming a G-quadruplex/PAT complex with low affinity for the WS2 nanosheet surface. This hybridization increased the distance between the Cy3 fluorophore and the WS2 nanosheets, inhibiting FRET and producing a strong FL signal. Under optimal experimental conditions, the FL intensity of the sensing system demonstrated an excellent linear correlation with PAT concentrations ranging from 0.5 to 40.0 ng mL-1, and it achieved a detection limit (S/N = 3) of 0.23 ng mL-1. This sensing system offers enhanced specificity for PAT detection and has the potential for broad application in detecting other toxins by substituting the sequence of the recognition aptamer.

Visualization detection of mycotoxin patulin in fruit juices by a small-molecule fluorescent probe

The mycotoxin patulin is a common contaminant in rotten fruits, posing severe food safety risks and threats to human health. Developing a convenient, sensitive and reliable method for patulin detection is of utmost importance but remains challenging. In this study, we have successfully designed and synthesized a small-molecule fluorescent probe, FITC-Lys, which demonstrates good sensitivity in detecting patulin. Upon contact with patulin, the terminal Lys group of the FITC-Lys probe reacts with patulin, resulting in the formation of the fluorescein dimer that subsequently quenches fluorescence. This variation of fluorescence enables the visualization and sensitive detection of patulin. The probe exhibits good sensitivity with a low LOD of 8 ng mL-1 for the fluorescence spectrum method and a LOD of 12 ng mL-1 for the fluorescence imaging method. Moreover, we have validated the probe's capability for patulin detection in apple and pear juices, achieving good recoveries ranging from 98.60% to 103.80%. Notably, the probe FITC-Lys is the first small-molecule fluorescent probe that has proven successful in visualizing patulin in juices derived from decayed apples and pears. Consequently, this probe holds great potential as a practical tool for monitoring patulin in foodstuffs, thereby contributing to enhanced food safety standards.

Sulfhydryl-functionalized carbon dots as effective probes for fluorescence enhancement detection of patulin

In this study, sulfydryl-functionalized nitrogen-doped carbon dots (SH-NCDs) was synthesized by amide reaction of hydrothermally synthesized carbon dots with l-cysteine and used to detect patulin selectively. The SH-NCDs exhibited excitation wavelength-independent fluorescence in the range 300-360 nm. The modified sulfhydryl group (-SH) on the surface of NCDs served as a specific recognition site to capture patulin. The addition reaction between patulin and the -SH on the SH-NCDs surface resulted in enhanced fluorescence. SH-NCDs was used as a fluorescent probe for label-free detection of patulin, showing excellent sensitivity in the linear range of 0.1-400 ng mL^-1, with detection limits as low as 0.053 ng mL^-1. The fluorescent probe has specific selectivity for patulin. The recoveries of patulin in apple juice and grape juice were 88.9 %-99.2 % and 92.5 %-101.8 %, respectively. These results showed that the sensor designed in this experiment selectively detected the target patulin from complex food systems.

Recent Progress in Aptamer-Functionalized Metal-Organic Frameworks-Based Optical and Electrochemical Sensors for Detection of Mycotoxins

Mycotoxin contamination in foodstuffs and agricultural products has posed a serious hazard to human health and raised international concern. The progress of cost-effective, facile, rapid and reliable analytical tools for mycotoxin determination is in urgent need. In this regard, the potential utility of metal-organic frameworks (MOFs) as a class of crystalline porous materials has sparked immense attention due to their large specific surface area, adjustable pore size, nanoscale framework structure and good chemical stability. The amalgamation of MOFs with high-affinity aptamers has resulted in the progress of advanced aptasensing methods for clinical and food/water safety diagnosis. Aptamers have many advantages over classical approaches as exceptional molecular recognition constituents for versatile bioassays tools. The excellent sensitivity and selectivity of the MOF-aptamer biocomposite nominate them as efficient lab-on-chip tools for portable, label-free, cost-effective and real-time screening of mycotoxins. Current breakthroughs in the concept, progress and biosensing applications of aptamer functionalized MOFs-derived electrochemical and optical sensors for mycotoxins have been discussed in this study. We first highlighted an overview part, which provides some insights into the functionalization mechanisms of MOFs with aptamers, offering a foundation to create MOFs-based aptasensors. Then, we discuss various strategies to design high-performance MOFs-based aptamer scaffolds, which serve as either signal nanoprobe carriers or signal nanoprobes and their applications. We perceived that applications of optical aptamers are in their infancy in comparison with electrochemical MOFs-derived aptasensors. Finally, current challenges and prospective trends of MOFs-aptamer sensors are discussed.

Maltose-functional metal-organic framework assisted laser desorption/ionization mass spectrometry for small biomolecule determination

A series of functional metal-organic frameworks (MOFs) were facilely prepared through an one-pot procedure or post-synthetic modification strategy and used as matrices in laser desorption ionization mass spectrometry (LDI-MS). Compared with traditional organic matrices and other MOFs, maltose-functional MOF MIL-101-maltose demonstrated ultrahigh ionization efficiency, free matrix background, uniform crystallization, and good dispersibility. A simple, general, and efficient LDI-MS platform was developed for rapid detection of various small biomolecules using MIL-101-maltose as matrix, providing several advantages including low sample consumption of 500 nL, short analysis time of few seconds, strong salt tolerance (500 mM NaCl), and satisfactory reproducibility. The MIL-101-maltose matrix was used for serum glucose determination and successfully distinguished the diabetic patients from the healthy controls. This work provides a generic LDI-MS platform for fast determination of small biomolecules with high potential in clinical diagnosis and disease monitoring.

Patulin Induces Acute Kidney Injury in Mice through Autophagy-Ferroptosis Pathway

Patulin (PAT) is a common mycotoxin, widely found in cereals, seafood, nuts, and especially in fruits and their products. Exposure to this mycotoxin has been reported to induce kidney injury. However, the possible mechanism remains unclear. In our study, short-term high-dose intake of PAT caused acute kidney injury (AKI) in mice. We performed high-throughput transcriptional sequencing to identify differentially expressed genes (DEGs) between the treatment and control groups. The ferroptosis signaling pathway had the highest enrichment, suggesting ferroptosis is involved in PAT-induced AKI. Further, the existence of ferroptosis and autophagy was confirmed by observing the changes of mitochondria morphology and the formation of autophagosomes by electron microscopy. And the expression of solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), p62, nuclear receptor coactivator 4 (NCOA4), and ferritin heavy chain 1 (FTH1) were downregulated, whereas acyl-CoA synthase long-chain family member 4 (ACSL4), transferrin (TF), LC3, and ferritin light chain (FTL) expression were upregulated in PAT-exposed mice. These results suggested autophagy-dependent ferroptosis occurred in the animal model. This view has also been confirmed in the human renal tubular epithelial cell (HKC) experiments. Autophagy inhibitor 3-methyladenine (3MA) attenuated PAT-induced ferroptosis and the iron contents in HKC cells. Simultaneous autophagy-dependent ferroptosis can be inhibited by ferroptosis inhibitors ferrostatin-1 (Fer-1) and desferrioxamine (DFO). In general, this study provides a new perspective for exploring the new mechanism of acute kidney injury caused by PAT.

A Sensitive Aptasensor Using Biotin-Streptavidin System for Patulin Detection in Apple Juice

Patulin contamination in fruits, vegetables, and their products is considered a serious health risk factor for food safety and human health. Thus, a rapid, simple detection method for patulin is becoming important, which could provide a tool for routine screening and food surveys. The objective of this study was to develop a sensitive aptamer-based lateral flow assay (FLA) using Streptavidin functionalized gold nanoparticles for sensitive patulin detection. An excellent dynamic range for patulin detection was obtained (2.7~139.8 ng/mL in the buffer and 7.07~359.5 ng/mL in the sample) with no affinity for other mycotoxins such as zearalenone (ZEN), ochratoxin A (OTA), aflatoxin B₁ (AFB₁), citrinin or tenuazonic acid (TEA). The limit of detection was 0.19 ng/mL in the buffer and 0.36 ng/mL in the real sample. The recoveries were 83.3% to 107.1%, with a satisfactory RSD value from 6.5% to 7.5%. Hence the established LFA could be used as a rapid, simple, on-site screening tool for PAT determination in apple juice.

The Occurrence and Contamination Level of Ochratoxin A in Plant and Animal-Derived Food Commodities

Ochratoxin A (OTA) is a highly toxic mycotoxin and poses great threat to human health. Due to its serious toxicity and widespread contamination, great efforts have been made to evaluate its human exposure. This review focuses on the OTA occurrence and contamination level in nine plant and animal derived food commodities: cereal, wine, coffee, beer, cocoa, dried fruit, spice, meat, and milk. The occurrence and contamination level varied greatly in food commodities and were affected by many factors, including spices, geography, climate, and storage conditions. Therefore, risk monitoring must be routinely implemented to ensure minimal OTA intake and food safety.

Toxic effects of patulin on mouse oocytes and its possible mechanisms

Patulin is a secondary metabolite mainly secreted by fungi and is the most common mycotoxin found in apples and apple-based products. For the past few years, numerous studies suggested the wide distribution and toxicity of patulin. In this study, we investigated the toxic effect of patulin on mouse oocytes and its possible mechanisms. The results showed that patulin treatment did not affect meiotic resumption, but inhibited oocyte maturation as indicated by failure of first polar body extrusion. Further mechanistic study showed that patulin treatment disturbed normal spindle assembly, chromosome alignment and morphology. We also found increased oxidative stress by testing the level of ROS and decreased mitochondrial membrane potential, indicating mitochondria dysfunction. In summary, our results suggest that patulin treatment causes oocyte meiotic arrest by disturbing normal spindle assembly and chromosome alignment, which may be caused by dysfunctions of mitochondria.

Development and validation of an extraction method using liquid chromatography-tandem mass spectrometry to determine patulin in apple juice

Patulin (PAT) is a potent mycotoxin commonly found in apples and apple-based products such as juice, thus affecting global food safety. Therefore, development of fast and simple analytical methods to effectively control its contamination is of great importance. This study developed and validated a technique for the analysis of PAT in samples of industrialized apple juice based on liquid-liquid extraction and using acetonitrile as the extraction solvent. Detection via mass spectrometry was performed after Atmospheric Pressure Chemical Ionization (APCI). Mean recoveries of 97.5, 92.49 and 96.92% were reached for 4, 8 and 20 μg/L of PAT, respectively. The analyte was monitored with an APCI source in negative ion mode to identify its fragments. The 24 analyzed samples presented PAT levels below the limit of quantification. It may be concluded that the method fulfilled all of the validation criteria, thus being appropriate for routine surveillance of PAT in apple juice.

Development of patulin certified reference material using mass balance and quantitative NMR

The certified reference materials (CRMs) are necessary for accurate quantification and insurance of comparability and traceability of results. Patulin is a typical mycotoxin in a variety of food commodities. Here, patulin CRM GBW(E)100673 was characterised and its purity was assessed by two independent orthogonal approaches including mass balance (MB) and quantitative nuclear magnetic resonance spectroscopy (qNMR) methods. From MB equation, the calculated purity was 996.9 mg/g with subtraction of water, volatile solvent, inorganic and structurally related impurities. In the other qNMR method, the calculated purity was 996.7 mg/g. This CRM was homogeneous and stable for at least 9 months under -20 °C in dark. Finally, a purity of 997 mg/g with an expanded uncertainty of 3 mg/g (k=2) was finally assigned to patulin CRM in this study. High-purity patulin CRM was fully characterised and assessed for the first time. The new CRM can be applicable to routine monitoring and risk assessment for assurance of accuracy results in food safety.

Adsorption Mechanism of Patulin from Apple Juice by Inactivated Lactic Acid Bacteria Isolated from Kefir Grains

In the food industry, microbiological safety is a major concern. Mycotoxin patulin represents a potential health hazard, as it is heat-resistant and may develop at any stage during the food chain, especially in apple-based products, leading to severe effects on human health, poor quality products, and profit reductions. The target of the study was to identify and characterize an excellent adsorbent to remove patulin from apple juice efficiently and to assess its adsorption mechanism. To prevent juice fermentation and/or contamination, autoclaving was involved to inactivate bacteria before the adsorption process. The HPLC (high-performance liquid chromatography) outcome proved that all isolated strains from kefir grains could reduce patulin from apple juice. A high removal of 93% was found for juice having a 4.6 pH, 15° Brix, and patulin concentration of 100 μg/L by Lactobacillus kefiranofacien, named JKSP109, which was morphologically the smoothest and biggest of all isolates in terms of cell wall volume and surface area characterized by SEM (Scanning electron microscopy) and TEM (transmission electron microscopy). C=O, OH, C–H, and N–O were the main functional groups engaged in patulin adsorption indicated by FTIR (Fourier transform–infrared). E-nose (electronic nose) was performed to evaluate the aroma quality of the juices. PCA (Principal component analysis) results showed that no significant changes occurred between control and treated juice.

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.

Determination of patulin in apple juice by amine-functionalized solid-phase extraction coupled with isotope dilution liquid chromatography tandem mass spectrometry

BACKGROUND

Patulin is a mycotoxin that mainly contaminates apple juice, which is a typical high sugar matrix. Many different adsorbents have been utilized to develop a sample pretreatment method to minimize the matrix interference from apple juice.

RESULTS

A simple and reliable extraction method for the determination of patulin in apple juice has been developed. The sample preparation involves a simple one-step cleanup procedure using amine-functionalized polymeric solid-phase extraction cartridges (Retain AX) that effectively remove interferences and facilitate the quantification. Isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) was employed to minimize the matrix effect and ensure reliable results. The limit of detection was as low as 0.2 μg kg^-1 , which was satisfactory with regard to current European, US, and Chinese legislation. Matrix-matched linearity (r² = 0.9997) was established in the range of 1-400 μg kg^-1 . Recovery was performed in samples spiked at three levels, and results were between 97.2% and 100.2%.

CONCLUSION

The results indicated that, with one-step cleanup, the matrix effect was negligible and sensitivity was satisfactory. Our work provided a simple and reliable method for patulin detection in apple juice and is also very promising in routine quality control. © 2020 Society of Chemical Industry.

Development of Two-Dimensional Nanomaterials Based Electrochemical Biosensors on Enhancing the Analysis of Food Toxicants

In recent times, food safety has become a topic of debate as the foodborne diseases triggered by chemical and biological contaminants affect human health and the food industry's profits. Though conventional analytical instrumentation-based food sensors are available, the consumers did not appreciate them because of the drawbacks of complexity, greater number of analysis steps, expensive enzymes, and lack of portability. Hence, designing easy-to-use tests for the rapid analysis of food contaminants has become essential in the food industry. Under this context, electrochemical biosensors have received attention among researchers as they bear the advantages of operational simplicity, portability, stability, easy miniaturization, and low cost. Two-dimensional (2D) nanomaterials have a larger surface area to volume compared to other dimensional nanomaterials. Hence, researchers nowadays are inclined to develop 2D nanomaterials-based electrochemical biosensors to significantly improve the sensor's sensitivity, selectivity, and reproducibility while measuring the food toxicants. In the present review, we compile the contribution of 2D nanomaterials in electrochemical biosensors to test the food toxicants and discuss the future directions in the field. Further, we describe the types of food toxicity, methodologies quantifying food analytes, how the electrochemical food sensor works, and the general biomedical properties of 2D nanomaterials.

Patulin Contamination of Citrus Fruits from Punjab and Northern Pakistan and Estimation of Associated Dietary Intake

This research aims to assess the natural occurrence of patulin (PAT) in selected citrus fruits from central cities of Punjab and Pakistan's northern cities. A total of 2970 fruit samples from 12 citrus cultivars were examined using liquid chromatography fitted with a UV detector. The detection limit (LOD) and quantification limit were 0.04 and 0.12 µg/kg, respectively. About 56% of samples of citrus fruits from Punjab's central cities, Pakistan, were found to be contaminated with PAT, with values ranging from 0.12 to 1150 µg/kg in samples from central Punjab cities. Furthermore, 31.7% of samples of citrus fruits from northern cities of Pakistan were contaminated with PAT, with values ranging from 0.12 to 320 µg/kg. About 22.1% of citrus fruit samples had PAT levels greater than the suggested limits established by the European Union (EU). The dietary intake levels of PAT ranged from 0.10 to 1.11 µg/kg bw/day in the central cities of Punjab, Pakistan, and 0.13 to 1.93 µg/kg bw/day in the northern cities of Pakistan.

Determination of patulin and hydroxymethylfurfural in beverages by UPLC-PDA

The present study describes using molecularly imprinted polymer (MIP) technology for determination of patulin (PAT) and 5-hydroxymethylfurfural (5-HMF) in beverages by ultra-high performance liquid chromatography coupled to photodiode array (UPLC-PDA). PAT (4-hydroxy-4H-furo[3,2-c]pyran-2(6H)-one) is a mycotoxin produced by Penicillium fungi and Penicillium expansum is probably the most commonly encountered species that infects apples during their growth, harvest, storage or processing. The occurrence of PAT as a natural contaminant of apples is a worldwide problem. 5-HMF (also known as 5-(hydroxymethyl) furan-2-carbaldehyde), is formed in the Maillard reaction as well as during caramelisation. It is a good storage time-temperature marker and flavour indicator, especially in beverages such as wine, beer, but also cider and apple juice which may contain PAT. PAT and 5-HMF were separated within 2 min using a Luna Omega C18 column and the PDA detector wavelength was set to 276 nm. The validation parameters of the analytical method such as linearity, limit of detection, limit of quantification, accuracy and precision were tested. The calibration curves were linear at least in the range 50-1000 ng/ml with a good linearity (R2>0.999) for both analytes, the limit of detection and the limit of quantification for PAT and 5-HMF were in the range 4.9-6.6 and 16.1-21.8 μg/l, respectively. The recoveries of the selected analyte were in the range 61.9-109.0% with a precision of <8.2% (relative standard deviation (RSD)) for PAT and in the range 50.8-98.0% with a precision of <10.0% (RSD) for 5-HMF. The validated procedure was successfully applied for the analysis of PAT and 5-HMF in beverages from retail shops.

Risk screening of mycotoxins and their derivatives in dairy products using a stable isotope dilution assay and LC-MS/MS

An liquid chromatography-tandem mass spectrometry method coupled with a stable isotope dilution assay was established for the simultaneous detection of 17 mycotoxins and their derivatives (aflatoxins B₁ , B₂ , G₁ , G₂ , M₁ , and M₂ ; fumonisins B₁ and B₂ ; ochratoxin A; zearalenone; zearalanone; α-zearalanol; α-zearalenol; T-2 toxin; deoxynivalenol; deepoxy-deoxynivalenol; and sterigmatocystin) in milk and dairy products. The mycotoxins were extracted with acidified acetonitrile and the lipids were removed using a Captiva EMR-lipid column. The average recoveries of the target compounds from samples spiked at three different concentrations were 67-102%, and the relative standard deviations of the peak areas were less than 10%. Limits of quantification (S/N = 10) of 0.004-1.25 μg/kg were achieved, which are significantly lower than the maximum levels allowed in various countries and regions for each regulated mycotoxin. Milk and yogurt products from local markets and e-commercial platforms were analyzed using the optimized method. The screening showed that aflatoxin M₁ , deoxynivalenol, fumonisins B₁ and B₂ , and zearalenone could be found in milk and yogurt products, especially those products also containing grains or jujube ingredients, indicating that there is a risk of mycotoxins in dairy products.

Patulin induces pyroptosis through the autophagic-inflammasomal pathway in liver

Patulin (PAT), a kind of mycotoxin, is produced by many common fungi in fruit and vegetable-based products. It has been shown to cause hepatotoxicity. However, the possible mechanisms are not completely elucidated. The present study aimed to characterize the role of autophagic-inflammasomal pathway on pyroptosis induced by PAT. In mouse livers, PAT induced pyroptosis, and increased inflammation through the activation of NLRP3 inflammasome. In liver cells, we noticed that PAT induced pyroptotic cell death, which was confirmed by the activation of GSDMD, caspase-1, the release of LDH, and the result of PI/Hoechst assay. In addition, PAT-induced pyroptosis was dependent upon the activation of NLRP3 inflammasome and the release of cathepsin B. Cells had less expression of caspase-1 and IL-1β protein levels after treated by NLRP3 inhibitor MCC950 or cathepsin B inhibitor CA-074Me. The expression of GSDMD and IL-1β protein levels were also decrease after treated by caspase-1 inhibitor Ac-YVAD-cmk. Moreover, autophagy inhibitor 3-methyladenine (3-MA) attenuated PAT-induced increase in cytoplasmic cathepsin B expression, and subsequent LDH release, the activation of NLRP3 inflamosomes, pyroptotic cell death, and inflammation. These findings suggested that PAT-induced pyroptosis maybe through autophagy-cathepsin B-inflammasomal pathway in the liver. These results provide new mechanistic insights into PAT-induced hepatotoxicity.

Molecular Aspects of Mycotoxins-A Serious Problem for Human Health

Mycotoxins are toxic fungal secondary metabolities formed by a variety of fungi (moulds) species. Hundreds of potentially toxic mycotoxins have been already identified and are considered a serious problem in agriculture, animal husbandry, and public health. A large number of food-related products and beverages are yearly contaminated by mycotoxins, resulting in economic welfare losses. Mycotoxin indoor environment contamination is a global problem especially in less technologically developed countries. There is an ongoing effort in prevention of mould growth in the field and decontamination of contaminated food and feed in order to protect human and animal health. It should be emphasized that the mycotoxins production by fungi (moulds) species is unavoidable and that they are more toxic than pesticides. Human and animals are exposed to mycotoxin via food, inhalation, or contact which can result in many building-related illnesses including kidney and neurological diseases and cancer. In this review, we described in detail the molecular aspects of main representatives of mycotoxins, which are serious problems for global health, such as aflatoxins, ochratoxin A, T-2 toxin, deoxynivalenol, patulin, and zearalenone.

Development of an immuno-electrochemical glass carbon electrode sensor based on graphene oxide/gold nanocomposite and antibody for the detection of patulin

The presence of fungal-produced patulin in foods poses a high health risk to people because it can cause neurologic and gastrointestinal illnesses. A glass carbon electrode (GCE) sensor was developed for the rapid and sensitive detection of patulin. Anti-patulin-BSA IgG of a rabbit was produced and immobilised on a GCE coated with a graphene oxide/gold nanocomposite. The mycotoxin patulin in the samples could be captured by the anti-patulin-BSA IgG on the surface of the GCE sensor. The spatial hindrance effect of IgG on the GCE sensor was reduced by the reaction between IgG and patulin, resulting in a decrease in the electron transfer resistance. The current changes in the immobilised anti-patulin-BSA IgG GCE sensor exhibited a linear relationship with patulin concentration and facilitated the sensitive detection of patulin. This immuno-electrochemical GCE sensor could rapidly detect patulin in less than 1 min with a detection limit of 5 µg/L.

In-line molecularly imprinted polymer solid phase extraction-capillary electrophoresis coupled with tandem mass spectrometry for the determination of patulin in apple-based food

We present a simple and sensitive method for the determination of patulin at µg·kg^-1 level in apple-based products. Our method relies on the application of an in-line molecularly imprinted polymer solid-phase extraction microcartridge in capillary electrophoresis coupled with mass spectrometry. Capillary zone electrophoresis method has been developed and parameters affecting the in-line process have been carefully optimized. Validation parameters were assessed for patulin, giving LOQ of 1 µg·kg^-1 and linearity range 1-100 µg·kg^-1 with R² ≥ 0.997. The LOQ was below the maximum content of patulin requested by the European Union in this type of products. The precision of the peak area and the migration time were less than 14.9 and 1.6%, respectively. Patulin has been analyzed in the presence of 5-hydroxymethylfurfural, which is the main interference in this kind of matrix. The method was applied to assay patulin content in various apple-based products.

Ultrasensitive competitive detection of patulin toxin by using strand displacement amplification and DNA G-quadruplex with aggregation-induced emission

A novel sensitive assay was established by using strand displacement amplification (SDA) and DNA G-quadruplex with aggregation-induced emission (AIE) for the detection of patulin (PAT) toxin. The complementary DNA (cDNA) of the aptamer and PAT competed for binding to aptamer-modified magnetic beads. The cDNA was obtained by magnetic separation and used as a primer in SDA to produce a large amount of G-base single-stranded DNA (ssDNA). They can form the G-quadruplex to be combined with the AIE of TTAPE dye, which features a special combination of G-quadruplex that amplify the fluorescent signals. This work can reach a lower detection limit of 0.042 pg mL^-1 with a wide linear range of 0.001-100 ng mL^-1 for PAT detection than other methods. The results also showed good recoveries of 97.8%-104% and 101.7%-105.3% in spiked apple and grape juices, respectively. The assay used for the detection of PAT exhibits high sensitivity and good specificity. It also provides a stable and reliable platform for detecting other small-molecule toxins.

Patulin Mycotoxin in Mango and Orange Fruits, Juices, Pulps, and Jams Marketed in Pakistan

The objective of the study was to explore the incidence of patulin (PAT) mycotoxin in mango and orange fruits and derived products marketed in Pakistan. A total of 274 samples, including 70 mango fruits, 63 mango-based products (juices, pulp, and jam), 77 orange fruits, and 64 orange-based products, were collected. PAT was determined by reverse-phase high-performance liquid chromatography (HPLC) with UV-Vis detector (276 nm). Linear detector response was observed (R2 > 0.99), the limit of detection (LOD) was 5 µg/kg and recovery percentage was 97.4%. The incidence of PAT in mango samples was 61.7%, and the concentration ranged from Collapse

Key Words

• food safety
• fruit-derived products
• mango
• orange
• patulin
• regulatory limits

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MESH Headings

• Beverages
• Chromatography, High Pressure Liquid
• Citrus sinensis
• Food Contamination
• Food Microbiology
• Fruit/microbiology
• Malus
• Mangifera/microbiology
• Pakistan
• Patulin/analysis
• Patulin/toxicity

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Grants Collapse

Affiliation(s)

Shabbir Hussain Food Toxicology Laboratory, Nuclear Institute for Agriculture and Biology College (NIAB-C), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Jhang Road, Faisalabad 38000, Pakistan; (S.H.); (N.K.); (S.W.-u.-H.) Central Analytical Facility Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), P. O. Nilore, Islamabad 45650, Pakistan
Muhammad Rafique Asi Food Toxicology Laboratory, Nuclear Institute for Agriculture and Biology College (NIAB-C), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Jhang Road, Faisalabad 38000, Pakistan; (S.H.); (N.K.); (S.W.-u.-H.)
Mazhar Iqbal Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Jhang Road, Faisalabad 38000, Pakistan
Nisha Khalid Food Toxicology Laboratory, Nuclear Institute for Agriculture and Biology College (NIAB-C), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Jhang Road, Faisalabad 38000, Pakistan; (S.H.); (N.K.); (S.W.-u.-H.)
Syed Wajih-ul-Hassan Food Toxicology Laboratory, Nuclear Institute for Agriculture and Biology College (NIAB-C), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Jhang Road, Faisalabad 38000, Pakistan; (S.H.); (N.K.); (S.W.-u.-H.)
Agustín Ariño Instituto Agroalimentario de Aragón—IA2 (Universidad de Zaragoza-CITA), Facultad de Veterinaria, 50013 Zaragoza, Spain;

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Specific antigen-based and emerging detection technologies of mycotoxins

Mycotoxins are secondary fungal metabolites produced by certain types of filamentous fungi or molds, such as Aspergillus, Fusarium, Penicillium, and Alternaria spp. Mycotoxins are natural contaminants of agricultural commodities, and their prevalence may increase due to global warming. According to the Food and Agriculture Organization of the United Nations, approximately 25% of the world's food crops are annually contaminated with mycotoxins. Mycotoxin-contaminated food and feed pose a high risk to both human and animal health. For instance, they possess carcinogenic, immunosuppressive, hepatotoxic, nephrotoxic, and neurotoxic effects. Hence, various approaches have been used to assess and control mycotoxin contamination. Significant challenges still exist because of the complex heterogeneous nature of food and feed composition. The potential of antigen-based approaches, such as enzyme-linked immunosorbent assay, flow injection immunoassay, chemiluminescence immunoassay, lateral flow immunoassay, and flow-through immunoassay, would contribute to our understanding about mycotoxins' rapid identification, their isolation, and the basic principles of the detection technologies. Additionally, we address other emerging technologies of potential application in the detection of mycotoxins. The data included in this review focus on basic principles and results of the detection technologies and would be useful as benchmark information for future research. © 2019 Society of Chemical Industry.

Adsorptive removal of patulin from apple juice via sulfhydryl-terminated magnetic bead-based separation

Patulin is a naturally produced toxin having potential carcinogenic properties. It is mainly produced by species of Penicillium growing on fruits, especially on apples. Detoxification of patulin, therefore, is very important for providing food safety. In this study, sulfhydryl-terminated, silica coated iron oxide beads were investigated as a multi-use sorbents for effective recovery of patulin from apple juice. The effect of beads amount, contact time, pH and temperature were evaluated for high adsorption capacity and the results showed maximum adsorption capacity at a reaction condition of 1.5 mg of beads for 4 h incubation at pH 7.2 and 25 °C. These sorbents were highly effective both in aqueous solution and apple juice with adsorption efficiencies of 99% and 71.25%, respectively. Adsorption process was explained by Langmuir isotherm model with pseudo-second order kinetic model. Thermodynamic parameters described spontaneous adsorption of patulin onto beads with high feasibility and preferences. The reusability of sulfhydryl coated magnetic beads was shown for at least four times without any significant decreases in efficiency. Results showed that this sorbent had potential for removal of patulin from apple juice without any negative effects on final quality parameters, Brix, color, clarity, total sugar and titratable acidity.

Electrostatic assembly of gold nanoparticles on black phosphorus nanosheets for electrochemical aptasensing of patulin

An aptamer based impedimetric assay for the mycotoxin patulin (PAT) is described. A glassy carbon electrode (GCE) was modified with black phosphorus nanosheets (BP NSs) and modified with PAT aptamer by electrostatic attraction. Detection is based on the variations of electron transfer resistance at the modified electrode surface. This assay can detect PAT over a linear range that extends from 1.0 nM to 1.0 μM with a 0.3 nM detection limit. To improve the performance of the sensor, the BP NS-GCE was further modified with gold nanoparticles and then with thiolated PAT aptamer. This modified electrode, operated at an applied potential of 0.18 V (vs. Ag/AgCl), has a wider linear range (0.1 nM to 10.0 μM) and a lower detection limits (0.03 nM). Both assays were successfully applied to the analysis of (spiked) genuine food samples. Graphical abstract Black phosphorus nanosheets (BP NSs) were used to fabricate an aptamer based assay for patulin. To further improve the performance of the electrode, gold nanoparticles (AuNP) were placed on the surface of black phosphorus nanosheets (AuNP-BP NSs) by electrostatic attraction for patulin aptasensing.

Patulin in Apples and Apple-Based Food Products: The Burdens and the Mitigation Strategies

Apples and apple-based products are among the most popular foods around the world for their delightful flavors and health benefits. However, the commonly found mold, Penicillium expansum invades wounded apples, causing the blue mold decay and ensuing the production of patulin, a mycotoxin that negatively affects human health. Patulin contamination in apple products has been a worldwide problem without a satisfactory solution yet. A comprehensive understanding of the factors and challenges associated with patulin accumulation in apples is essential for finding such a solution. This review will discuss the effects of the pathogenicity of Penicillium species, quality traits of apple cultivars, and environmental conditions on the severity of apple blue mold and patulin contamination. Moreover, beyond the complicated interactions of the three aforementioned factors, patulin control is also challenged by the lack of reliable detection methods in food matrices, as well as unclear degradation mechanisms and limited knowledge about the toxicities of the metabolites resulting from the degradations. As apple-based products are mainly produced with stored apples, pre- and post-harvest strategies are equally important for patulin mitigation. Before storage, disease-resistance breeding, orchard-management, and elicitor(s) application help control the patulin level by improving the storage qualities of apples and lowering fruit rot severity. From storage to processing, patulin mitigation strategies could benefit from the optimization of apple storage conditions, the elimination of rotten apples, and the safe and effective detoxification or biodegradation of patulin.