Patulin in homogenized fruit's and tomato products

The fate of mycotoxins in oranges during storage and processing

To evaluate the safety of orange consumption induced by mycotoxins, 'Newhall' navel oranges were artificially inoculated with P. expansum and A. tenuissima, followed by an evaluation of the distribution and migration patterns of corresponding mycotoxins (patulin [PAT], tentoxin [Ten], altenuene [ALT], alternariol monomethyl ether [AME], alternariol [AOH] and tenuazonic acid [TeA]) during orange storage and processing. The concentration of mycotoxins decreased as the increase of distance from the lesion, and mycotoxins could be detected throughout the orange when the lesion extended to 8 mm in diameter. AOH and AME pose the primary source of dietary risk with high concentrations and low thresholds of toxicological concern. Orange juice and pectin processing could remove 43.4-98.7% of mycotoxins, while tangerine peelprocessing might lead to significant enrichment of mycotoxins with the processing factors (PFs) of 2.8-3.5. The findings may offer scientific insights into mitigating the dietary risk of mycotoxin exposure from oranges and their derivatives.

High-Throughput Bioassay for Detection of Latent Fungi in Postharvest Produce

Enormous fresh agricultural produce is wasted annually due to rots caused by pathogenic microorganisms. Most pathogenic fungi attack the harvested produce by penetrating the fruit at the field and remaining quiescent or latent until the fruit ripens or senescence. In this work, a recently developed simple, cost-effective, and high-throughput 96-well plate-based assay was applied to determine the presence of pathogenic fungi in their latent stage. The surface strands immobilized on the 96-well plate, only with the presence of the complementary RNA marker (enoyl-CoA hydratase (ECH)) of the latent fungal-pathogen Colletotrichum gloeosporioides will create a complex with the target and reporter (labeled with the horseradish peroxidase (HRP) enzyme) strands for positive signal generation. The developed assay demonstrated 3.1-fold higher specificity for the latent marker (ECH) of C. gloeosporioides compared to latent markers of other pathogenic fungi. A 2 nM detection limit of target strands was demonstrated, showing a high plate sensitivity, and was further validated with biological samples extracted from latent infection in tomato fruit. The developed assay provides a new economical tool for detecting the presence of latent RNA markers of pathogenic fungi in agricultural produce, ultimately improving postharvest decision-making and reducing postharvest losses.

Contamination, Detection and Control of Mycotoxins in Fruits and Vegetables

Mycotoxins are secondary metabolites produced by pathogenic fungi that colonize fruits and vegetables either during harvesting or during storage. Mycotoxin contamination in fruits and vegetables has been a major problem worldwide, which poses a serious threat to human and animal health through the food chain. This review systematically describes the major mycotoxigenic fungi and the produced mycotoxins in fruits and vegetables, analyzes recent mycotoxin detection technologies including chromatography coupled with detector (i.e., mass, ultraviolet, fluorescence, etc.) technology, electrochemical biosensors technology and immunological techniques, as well as summarizes the degradation and detoxification technologies of mycotoxins in fruits and vegetables, including physical, chemical and biological methods. The future prospect is also proposed to provide an overview and suggestions for future mycotoxin research directions.

Patulin in food: A mycotoxin concern for human health and its management strategies

The mycotoxin patulin is primarily produced as a secondary metabolite by numerous fungal species and predominantly by Aspergillus, Byssochlamys, and Penicillium species. It is generally associated with fungal infected food materials. Penicillium expansum is considered the only fungal species liable for patulin contamination in pome fruits, especially in apples and apple-based products. This toxin in food poses serious health concerns and economic threat, which has aroused the need to adopt effective detection and mitigation strategies. Understanding its origin sources and biosynthetic mechanism stands essential for efficiently designing a management strategy against this fungal contamination. This review aims to present an updated outline of the sources of patulin occurrence in different foods and their biosynthetic mechanisms. It further provides information regarding the detrimental effects of patulin on human and agriculture as well as its effective detection, management, and control strategies.

Patulin, ergosterol and Howard mold count (HMC): Which one is the best quality indicator for tomatoes?

Ergosterol, an important constituent of fungal cell wall, was started to be used as a quality parameter for the tomatoes and derivatives instead of Howard mold count (HMC). In addition, patulin is another important microbiological quality indicator of molds such as Penicillium, Aspergillus, and Byssochlamys. In this study, it is aimed to identify the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which has the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. As the rotten proportion increased, HMC, ergosterol, and patulin values increased. Linear correlations (r) between HMC, ergosterol, patulin, and rotten proportion were calculated as 0.99, 0.99, and 0.98, respectively. In addition, linear correlations between HMC and ergosterol (r = 0.95), HMC and patulin (r = 0.95) and ergosterol and patulin (r = 0.98) were found. In contrast, non-linear correlation between pH, brix and titratable acidity, and the rotten proportion was determined. PRACTICAL APPLICATIONS: The manuscript has provided the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which have the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. Linear correlations between rotten proportions of tomatoes and HMC, ergosterol, patulin and between HMC and ergosterol, HMC and patulin, and ergosterol and patulin were determined in juices produced from rotten tomatoes. Patulin indicated correlation with HMC and ergosterol in juices produced from rotten tomatoes. In addition to HMC and ergosterol, patulin has great potential for the assessment of tomato products as associated with the rotten proportion.

Mycotoxin patulin in food matrices: occurrence and its biological degradation strategies

Patulin is a mycotoxin produced by a number of filamentous fungal species. It is a polyketide secondary metabolite which can gravely cause human health problems and food safety issues. This review deals with the occurrence of patulin in major food commodities from 2008 to date, including historical aspects, source, occurrence, regulatory limits and its toxicity. Most importantly, an overview of the recent research progress about the biodegradation strategies for contaminated food matrices is provided. The physical and chemical approaches have some drawbacks such as safety issues, possible losses in the nutritional quality, chemical hazards, limited efficacy, and high cost. The biological decontamination based on elimination or degradation of patulin using yeast, bacteria, and fungi has shown good results and it seems to be attractive since it works under mild and environment-friendly conditions. Further studies are needed to make clear the detoxification pathways by available potential biosorbents and to determine the practical applications of these methods at a commercial level to remove patulin from food products with special reference to their effects on sensory characteristics of foods.

Development and comparison of single-step solid phase extraction and QuEChERS clean-up for the analysis of 7 mycotoxins in fruits and vegetables during storage by UHPLC-MS/MS

A robust and sensitive UHPLC-MS/MS method was developed for the analysis of seven mycotoxins in fruits and vegetables. The variations of seven mycotoxins concentrations during storage were also determined for the first time. Solid phase extraction (SPE) and QuEChERS clean-up were compared, and extraction was finally performed with acetonitrile under acidic conditions followed by HLB SPE purification. Seven mycotoxins were separated on a C18 column by gradient elution, scanned by ESI⁺ and ESI^- dynamic switching and detected with MRM mode. LOD and LOQ, matrix effect, accuracy and precision of the developed method were investigated. Results were linear in their concentration ranges for all mycotoxins with R² being greater than 0.999. LODs and LOQs were ranged from 0.05 to 3.0 μg/kg and 0.2 to 10.0 μg/kg, respectively. Average recoveries were between 81.1% and 116% with intraday- and interday-precision being in the ranges of 3.0-6.2% and 4.2-6.1%, respectively. The validated method provides sufficient selectivity, sensitivity and accuracy to screen for seven mycotoxins at trace levels, without using standard addition or matrix-matched calibration to compensate for matrix effects. The method was successfully applied for mycotoxins analysis in fruits and vegetables. None were detected in fresh samples, but AOH and AME were detected in strawberry, and TeA was detected in tomato fruits during long-term storage. Their concentrations were in the range of 3.6-165.3 μg/kg from 3 days to 60 days and significantly increased along with storage time.

Identification of differentially expressed genes involved in spore germination of Penicillium expansum by comparative transcriptome and proteome approaches

In this study, Penicillium expansum, a common destructive phytopathogen and patulin producer was isolated from naturally infected apple fruits and identified by morphological observation and rDNA-internal transcribed spacer analysis. Subsequently, a global view of the transcriptome and proteome alteration of P. expansum spores during germination was evaluated by RNA-seq (RNA sequencing) and iTRAQ (isobaric tags for relative and absolute quantitation) approaches. A total of 3,026 differentially expressed genes (DEGs), 77 differentially expressed predicted transcription factors and 489 differentially expressed proteins (DEPs) were identified. The next step involved screening out 130 overlapped candidates through correlation analysis between the RNA-seq and iTRAQ datasets. Part of them showed a different expression trend in the mRNA and protein levels, and most of them were involved in metabolism and genetic information processing. These results not only highlighted a set of genes and proteins that were important in deciphering the molecular processes of P. expansum germination but also laid the foundation to develop effective control methods and adequate environmental conditions.

Mitigation of Patulin in Fresh and Processed Foods and Beverages

Patulin is a mycotoxin of food safety concern. It is produced by numerous species of fungi growing on fruits and vegetables. Exposure to the toxin is connected to issues neurological, immunological, and gastrointestinal in nature. Regulatory agencies worldwide have established maximum allowable levels of 50 µg/kg in foods. Despite regulations, surveys continue to find patulin in commercial food and beverage products, in some cases, to exceed the maximum limits. Patulin content in food can be mitigated throughout the food processing chain. Proper handling, storage, and transportation of food can limit fungal growth and patulin production. Common processing techniques including pasteurisation, filtration, and fermentation all have an effect on patulin content in food but individually are not sufficient safety measures. Novel methods to remove or detoxify patulin have been reviewed. Non-thermal processing techniques such as high hydrostatic pressure, UV radiation, enzymatic degradation, binding to microorganisms, and chemical degradation all have potential but have not been optimised. Until further refinement of these methods, the hurdle approach to processing should be used where food safety is concerned. Future development should focus on determining the nature and safety of chemicals produced from the breakdown of patulin in treatment techniques.