Agricultural and Biological Sciences, Food Science
68
Scopus Publications
Scopus Publications
Detection of deoxynivalenol, its modified forms, and zearalenone in individual oat grains using visible-near-infrared spectroscopy and near-infrared hyperspectral imaging Irene Teixido-Orries, Francisco Molino, Carol Verheecke-Vaessen, Angel Medina, Sonia Marín Food Control, 2026 Fusarium mycotoxins such as deoxynivalenol (DON), its modified forms, and zearalenone (ZEN) frequently contaminate oats, posing serious health and regulatory concerns. This study assessed the use of visible-near-infrared (Vis-NIR) spectroscopy and near-infrared hyperspectral imaging (NIR-HSI) to classify individual oat grains according to the European legal limits for DON (1,750 μg/kg) and ZEN (100 μg/kg). NIR-HSI consistently outperformed Vis-NIR, achieving classification accuracies (CAs) above 91% and F1-scores above 0.65 for DON, ZEN and combined DON+ZEN detection. The most informative spectral regions were in the NIR ranges of 1000-1250 nm and 1300-1500 nm, associated with Fusarium -induced biochemical and structural changes in oat grains. Reducing the spectral input to 20 selected wavelengths preserved NIR-HSI performance, supporting the feasibility of multispectral implementations. These targeted, non-destructive approaches could enable early removal of the few highly contaminated grains responsible for batch rejection, improving food safety, reducing waste, and enhancing the sustainability of oat processing. • Vis-NIR and NIR-HSI classified DON and ZEN-contaminated oats with >91% accuracy. • Removing ∼9% of grains could reduce DON-3G, 15-ADON and 3-ADON levels by >95%. • Optimal models relied on key wavelengths in the 1000-1200 and 1300-1500 nm ranges. • Reducing models to 20 wavelengths retained >92% accuracy across NIR-HSI methods. • Combined models enabled simultaneous detection of multiple Fusarium mycotoxins.
Aflatoxin in Rwanda: climatic factors, retailers’ social-demography, awareness, handling practices and contamination levels in peanuts A. Niyonshima, M. Niyibituronsa, J.P. Hategekimana, T. Hagenimana, W. Wafula, I. Kamaraba, F. Uwamahoro, C. Verheecke-Vaessen, V. Ndayambaje World Mycotoxin Journal, 2026 This study investigates aflatoxin contamination in peanut products and associated socio-demographic, knowledge, and handling factors among retailers in Rwanda. A cross-sectional survey was conducted involving 300 retailers across five provinces, employing structured interviews to collect data on socio-demographic characteristics, aflatoxin awareness, and handling practices. Quantitative analysis of aflatoxin levels in peanut flour and kernels was performed using a portable, ISO-validated Raptor Reader Neogen Model 9680 (Neogen Corporation, Lansing, MI, USA), which interprets results obtained from lateral flow immunoassays. Data were analysed through descriptive statistics, Pearson correlation, and analysis of variance (ANOVA). Findings revealed that awareness of aflatoxins was limited, with only 28.3% of retailers cognizant of their presence in peanut products and 21.0% are aware of their health implications. Handling practices showed a high prevalence of kernel sorting before sale or processing (98.6%), yet inadequate packaging materials, such as buckets (44.7%) and polypropylene bags (35.3%) were commonly used. Aflatoxin concentrations in samples were substantially elevated, with a mean of 62.75 μ g/kg, exceeding international safety thresholds. Statistically significant differences in aflatoxin levels were observed between sample types ( P < 0.05), with peanut flour exhibiting higher contamination (mean 92.47 μ g/kg) than peanut kernels (mean 35.31 μ g/kg). Notably, 69.4% of peanut flour samples and 44.2% of peanut kernel samples surpassed the Rwandan regulatory limit of 10 μ g/kg. Geographical analysis indicated significant inter-provincial variation, particularly between Kigali City and the Western Province. These results highlight a critical public health concern due to elevated aflatoxin levels, exacerbated by limited awareness and substandard handling practices. To mitigate exposure, targeted educational campaigns, improved storage practices, and stricter regulatory enforcement, potentially facilitated by rapid on-site screening using lateral flow immunoassays coupled with portable readers, are urgently needed to enhance food safety and protect consumers.
First evidence of SO2-releasing bags controlling fungal growth, aflatoxins, and cyclopiazonic acid contamination in unshelled peanuts Carla Cervini, Vaibhav Verma, Carol Verheecke-Vaessen, Angel Medina, Naresh Magan Letters in Applied Microbiology, 2026 Peanuts (also known as groundnuts; Arachis hypogaea L.) are a globally significant cash crop but are highly susceptible to fungal contamination, particularly by Aspergillus section Flavi, which can contaminate the product with mycotoxins, including aflatoxins. This contamination poses serious food safety concerns, especially in low- and middle-income countries, limiting access to international markets. This study assessed the efficacy of slow-release SO2-bags compared to plastic bags (control) in reducing fungal growth and mycotoxin contamination in stored unshelled peanuts. Naturally contaminated and Aspergillus flavus-inoculated peanuts were stored at water activity (aw) levels of 0.85 and 0.95 for 15 days at 25°C. Fungal populations were monitored, and aflatoxins and cyclopiazonic acid were analysed using LC-MS/MS qTRAP. SO2-releasing bags completely inhibited fungal growth in naturally contaminated peanuts and significantly reduced A. flavus population with effectiveness dependent on water activity. Additionally, SO2-releasing bags suppressed mycotoxin production. This study demonstrates, for the first time, the effectiveness of SO2-releasing bags in preventing fungal spoilage and mycotoxin contamination in postharvest peanuts, offering a promising solution for enhancing peanut safety and quality.
Visible-near infrared spectroscopy and near-infrared hyperspectral imaging for the detection of T-2 and HT-2 toxins in individual oat grains Irene Teixido-Orries, Francisco Molino, Pau Agusti-Fernandez, Ebenezer Ayibiowu, Derek Croucher, Angel Medina, Sonia Marín, Carol Verheecke-Vaessen Food Control, 2026 Oat grains are increasingly consumed worldwide due to their health benefits, yet they are highly susceptible to contamination by Fusarium toxins, particularly T-2 and HT-2 toxins (T-2+HT-2). These toxins pose serious health risks and are unevenly distributed, with a few highly contaminated grains often driving a batch over legal safety limits. Current detection methods are destructive, slow, or inadequate for detecting contamination at the individual grain level. This study is the first to demonstrate the potential of visible–near-infrared (Vis-NIR) spectroscopy and near-infrared hyperspectral imaging (NIR-HSI) to detect T-2+HT-2 in individual oat grains non-destructively. 200 grains were scanned, and their toxin content quantified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Classification models were developed to identify grains exceeding both the European Union (EU) legal threshold (1250 μg/kg) and a higher risk level (10,000 μg/kg). Both techniques achieved high accuracy (up to 94.5 %) in identifying contaminated grains. Key wavelengths were identified (e.g., 1203, 1419, 1424 and 1476 nm in NIR; 440–455 nm in Vis), and reducing the model to 20 wavelengths preserved performance while simplifying computation. Critically, removing just 21.5 % of the most contaminated grains could reduce overall toxin levels by over 95 %. Moreover, sampling simulations revealed that analysing 30 % of grains guarantees detection of contamination above legal limits, whereas 0.5 % sampling yields only a 25–33 % detection chance. These findings highlight a feasible path for integrating spectroscopic screening into industrial oat sorting lines, improving food safety, reducing economic losses, and overcoming key limitations of conventional mycotoxin monitoring. • Vis-NIR and NIR-HSI identify oat grains with high T-2+HT-2 levels (>90 % accuracy). • Discarding 11 % of grains with >10,000 μg/kg cuts toxin levels by over 90 %. • Vis-NIR captures visual damage; NIR-HSI detects toxin-linked chemical shifts. • Sampling 30 % of grains ensures EU compliance for T-2 and HT-2 toxins detection. • Reducing models to 20 wavelengths keeps >94 % accuracy and boosts feasibility.
Detection of Fusarium spp. and T-2 and HT-2 toxins contamination in oats using visible and near-infrared spectroscopy Irene Teixido-Orries, Lexuan Yang, Francisco Molino, Angel Medina, Sonia Marín, Carol Verheecke-Vaessen International Journal of Food Microbiology, 2025 Fusarium langsethiae (FL) is one of the major contaminants in oats in the United Kingdom (UK) and is a significant producer of T-2 and HT-2 toxins, among the most prevalent mycotoxins in oats. Visible and near-infrared (Vis-NIR) (350–2500 nm) spectroscopy was explored as a non-invasive, rapid method for detecting FL, Fusarium species that produce T-2 and HT-2 toxins, and T-2 and HT-2 toxins content. Oat grains were artificially inoculated with FL and other Fusarium species under controlled water activity (a w ) conditions (0.98, 0.90, and 0.80). FL was found to be particularly responsible for producing T-2 and HT-2 toxins. Classification models were developed to distinguish oat grains based on the presence of FL. The best performance was achieved with all the Vis-NIR spectra, with a classification accuracy of 76.2 %. The Vis region (350–995 nm) emerged as the most important range for classification. Additionally, oat grains were classified by T-2 and HT-2 toxin content, distinguishing oats above and below the European Union (EU) threshold with 93.3 % accuracy. For mycotoxin quantification, the best performance was obtained using the Vis region with a coefficient of determination (R 2 ) of 0.875. Key wavelengths such as 464, 568, 575 and 636 nm were relevant for toxin detection. The NIR region (1005–1795 nm) also played a significant role in the models. This study shows that Vis-NIR spectroscopy is a promising, non-destructive tool for detecting Fusarium and type A trichothecenes in oats, though further research is needed to improve model robustness and support food safety monitoring.
Venturia inaequalis Can Initiate Sexual Reproduction Prior to Leaf-Fall: New Electron Microscopy Evidence Katherine Stewart, Thomas Passey, Carol Verheecke‐Vaessen, Zoltan Kevei, Xiangming Xu Plant Pathology, 2025 Apple scab, caused by Venturia inaequalis , is a major disease of cultivated apples ( Malus × domestica ) worldwide. Annually, there is one cycle of sexual reproduction (ascospores) in V . inaequalis between strains of two opposite mating types. Sexual reproduction mainly occurs on leaf litter over the winter, and mature ascospores readily infect young leaves the following spring. We do not yet know whether sexual reproduction is initiated before or after leaf‐fall in autumn. The timing of sexual reproduction initiation can significantly impact the exchange of genetic information among pathogen strains. In this study, we used scanning electron microscopy (SEM) to determine the timing of sex initiation, in particular, whether sex can initiate between lesions on the same leaf prior to leaf‐fall. SEM images showed that pseudothecial structures begin to develop before leaf‐fall on leaves with either multiple lesions or a single lesion. Following an overwintering period under laboratory conditions, however, the pseudothecia on leaves with multiple lesions were larger and more mature than those on leaves with a single lesion, where initial pseudothecial structures were present but did not develop further. Thus, the results suggest that the initiation of sexual reproduction in V . inaequalis can occur prior to leaf‐fall in autumn, limiting the opportunities for sexual recombination among strains from different leaves.
Will climate change affect growth and ochratoxin A production of putative biocontrol knockout strains of Aspergillus carbonarius? Belén Llobregat, Carla Cervini, Luis González-Candelas, Carol Verheecke-Vaessen, Ana-Rosa Ballester, Ángel Medina International Journal of Food Microbiology, 2025 The research explored the effects of abiotic factors associated with climate change (CC) on the growth and metabolite production of wild-type Aspergillus carbonarius ITEM 5010 and three knockout mutants: one knockout in the first gene of the ochratoxin A (OTA) biosynthesis pathway (Δ otaA ) and two in the veA and laeA genes (the latter knockout generated in this work) encoding VELVET complex proteins, which regulate metabolism. Variables examined were temperature (30 °C vs 37 °C), water activity (0.98 vs 0.90), and CO₂ levels (400 ppm vs 1000 ppm). Growth, OTA production, and other metabolites were evaluated on grape-based medium. The results showed that abiotic factors significantly influenced fungal growth and mycotoxin production, with a w being the most critical parameter. At a w 0.90, no growth was observed. A temperature of 37 °C combined with 1000 ppm CO₂ resulted in higher OTA production, indicating a greater health risk in predicted CC scenarios. Mutants of global regulatory factors showed altered metabolite production, with elevated OTA levels at 37 °C. The Δ otaA knockout mutant consistently showed no OTA production, suggesting its viability as a biocontrol agent under CC conditions. However, while OTA increased, other secondary metabolites, such as pyranonigrin A and kojic acid, decreased with rising temperatures in all strains. The research highlights the influence of abiotic factors related to CC on A. carbonarius growth and metabolite production, underlining the threat of increased mycotoxin production. This reinforces the need for resilient biocontrol strategies. The Δ otaA mutant has been identified as a potential biocontrol agent, demonstrating resistance to future environmental stresses associated with CC. • Δ laeA knockout grows and sporulates like WT but nearly eliminates OTA production • CC scenarios affect growth and secondary metabolite production in A. carbonarius • Growth is mainly impacted by a ᴡ , while OTA rises with high CO₂ and temperature • Δ veA , Δ laeA restore OTA under stress, but Δ otaA remains unable to produce it • CC factors may increase OTA/OTB but reduce kojic acid, pyranonigrin A
Atoxigenic isolates of Aspergillus flavus effectively reduce cyclopiazonic acid in a sorghum-based matrix under simulated abiotic stress conditions Vanshika Sharma, Carla Cervini, Carol Verheecke-Vaessen, Ranajit Bandyopadhyay, Angel Medina, Alejandro Ortega-Beltran, Naresh Magan Letters in Applied Microbiology, 2025 Maize, groundnut, and sorghum are important staple crops in several countries, but are prone to mycotoxin contamination. In the tropics and subtropics, Aspergillus flavus frequently contaminates those crops with aflatoxins and, sometimes, with cyclopiazonic acid (CPA). However, some genotypes cannot produce one or both toxins. In various countries, atoxigenic isolates of A. flavus are formulated into biocontrol products for field use to outcompete aflatoxin producers. The products effectively limit aflatoxin but their utility to reduce CPA remains unexplored. The abilities of four atoxigenic isolates (AF−) from Burkina Faso to control CPA by an isolate with high capacity to produce aflatoxins (AF+) and CPA was tested in co-inoculations at varying ratios (100+, 75+/25−, 50+/50−, 25+/75−, 100−), under simulated abiotic stress conditions. Experiments were conducted on 2% sorghum-based media at 0.95 and 0.90 water activity (aw), at 30°C and 37°C, for 12 days. CPA was quantified using liquid chromatography tandem mass spectroscopy. CPA concentrations gradually decreased as the proportion of atoxigenic isolates increased, with effectiveness varying depending on the environmental conditions.
Fusarium graminearum and zearalenone in wheat: A water activity–temperature model B. Ingram, S. Marin, E. Kiaitsi, N. Magan, C. Verheecke-Vaessen, C. Cervini, F. Rubio-Lopez, E. Garcia-Cela Fungal Biology, 2025 < 0.89 should be maintained, and temperatures in the range 18-31 °C should be avoided (P < 0.5). The integration of predictive models into decision support systems could assist farmers in identifying pre-harvest contamination risks and in optimising harvesting and drying practices to minimise post-harvest contamination. This study highlights the importance of understanding the ecophysiological profiles of mycotoxigenic species like F. graminearum to mitigate contamination risks and optimise storage conditions in wheat.
Incidence of mycobiota and aflatoxin B1 in Algerian feed Karima Bouti, Nouara Ait Mimoune, Salim Mokrane, Nadjette Djemouai, Carol Verheecke Vaessen, Florence Mathieu, Amar Riba International Journal of Postharvest Technology and Innovation, 2022
BIOLOGICAL ACTIVITIES OF Streptomyces sp. BTS40 ISOLATED FROM THE RHIZOSPHERE OF Artemisia herba-alba Asso Analele Universitatii Din Oradea Fascicula Biologie, 2022
Visualizing the invisible: class excursions to ignite children’s enthusiasm for microbes Terry J. McGenity, Amare Gessesse, John E. Hallsworth, Esther Garcia Cela, Carol Verheecke‐Vaessen, Fengping Wang, Max Chavarría, Max M. Haggblom, Søren Molin, Antoine Danchin, Eddy J. Smid, Cédric Lood, Charles S. Cockell, Corinne Whitby, Shuang‐Jiang Liu, Nancy P. Keller, Lisa Y. Stein, Seth R. Bordenstein, Rup Lal, Olga C. Nunes, Lone Gram, Brajesh K. Singh, Nicole S. Webster, Cindy Morris, Sharon Sivinski, Saskia Bindschedler, Pilar Junier, André Antunes, Bonnie K. Baxter, Paola Scavone, Kenneth Timmis Microbial Biotechnology, 2020
