Modelling the Combined Effects of Oxalic Acid, Water Activity, and pH on the Growth and Mycotoxin Production of Aspergillus spp. in a Dried Fig System

This study aimed to model the effects of aw, pH, and OA, a compound commonly used as a plant elicitor, on the growth and mycotoxin production of Aspergillus welwitschiae and Aspergillus flavus on a fig-based model substrate. Using RSM with a BBD, the combined impact of aw (0.92–0.99), pH (5.6–6.3), and OA (1–2 mM) on growth and mycotoxin production was evaluated under fixed temperature cycle simulating field conditions. HPLC-FLD quantified OTA and AFs. The results revealed that aw was the most influential factor governing fungal behaviour. The driest aw (0.92) significantly delayed growth and completely inhibited the production of OTA and AFB1. Conversely, high aw (0.99) was a prerequisite for significant mycotoxin accumulation. While OA at the tested elicitor concentrations did not prove to be a potent independent inhibitor of mycotoxins, its interactions with aw and pH did significantly delay fungal growth. The high R2 values (>96%) for growth models indicated a strong goodness-of-fit for comparing the relative impact of the factors. The models for mycotoxins had more moderate R2 values, a common finding reflecting the complexity of secondary metabolism. Consequently, these models should be regarded as semi-quantitative tools for identifying high-risk trends rather than for precise prediction. Following internal validation, all developed models proved to be valuable semi-quantitative tools for identifying high-risk conditions, including those with more modest R2 values like the OTA model (R2 = 56.5%, validation R > 0.945).

• Publication year

  2025

• Venue

  Foods

• Publication date

  2025-11-01

• Fields of study

  Biology, Medicine, Environmental Science

• Identifiers
  DOI 10.3390/foods14223854PMID 41300011PMCID 12651421
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

• Optimization of low-temperature nitrogen plasma in reducing fungi and aflatoxin human exposure through maize

  2025cited by this paper
• Response Surface Methodology-Based Optimization for Enhancing the Viability of Microencapsulated Lactobacillus plantarum in Composite Materials

  2025cited by this paper
• Role of oxalic acid in fungal and bacterial metabolism and its biotechnological potential

  2024cited by this paper
• Inferring fungal growth rates from optical density data

  2024cited by this paper
• Yellow Pitahaya (Selenicereus megalanthus Haw.) Growth and Ripening as Affected by Preharvest Elicitors (Salicylic Acid, Methyl Salicylate, Methyl Jasmonate, and Oxalic Acid): Enhancement of Yield, and Quality at Harvest

  2024cited by this paper
• Implementation of netting system for production of ‘Calabacita’ dried figs: Effects on pest incidence, fruit quality and mycotoxin occurrence

  2024cited by this paper
• Elicitors: impact on the fungal pathogenicity and colonization in fruits

  2024cited by this paper
• Intensification and characterization of biosorption of microalgal cells on filamentous fungal pellets as effective tools for harvesting of microalgal biomass

  2024cited by this paper
• Advancements in Predictive Microbiology: Integrating New Technologies for Efficient Food Safety Models

  2024cited by this paper
• Oxalic acid: A blooming organic acid for postharvest quality preservation of fresh fruit and vegetables

  2023cited by this paper
• Quantification and Identification of Damage Caused by Pests and Fungi in Dried Figs from Orchards with Different Levels of Agronomic Management in the Main Production Areas of Extremadura (Sw Spain)

  2023cited by this paper
• Phylogenomics reveals extensive misidentification of fungal strains from the genus Aspergillus

  2022cited by this paper
• Effect of Water Activity on Conidia Germination in Aspergillus flavus

  2022influential reference
• Evaluation of fungal hazards associated with dried fig processing.

  2022cited by this paper
• Control of toxigenic Aspergillus spp. in dried figs by volatile organic compounds (VOCs) from antagonistic yeasts.

  2022cited by this paper
• Optimal conditions for oxalic acid production by Aspergillus niger and A. flavus

  2021cited by this paper
• Predictive Modeling and Validation on Growth, Production of Asexual Spores and Ochratoxin A of Aspergillus Ochraceus Group under Abiotic Climatic Variables

  2021cited by this paper
• Use of predictive modelling as tool for prevention of fungal spoilage at different points of the food chain

  2021cited by this paper
• Effect of Temperature during Drying and Storage of Dried Figs on Growth, Gene Expression and Aflatoxin Production

  2021cited by this paper
• Consumer Preference, Quality, and Safety of Organic and Conventional Fresh Fruits, Vegetables, and Cereals

  2021cited by this paper
• Pre-Harvest Oxalic Acid Application Improves Fruit Size at Harvest, Physico-Chemical and Sensory Attributes of ‘Red Flesh’ Apricot During Fruit Ripening

  2021cited by this paper
• Organic acid, a virulence factor for pathogenic fungi, causing postharvest decay in fruits

  2021cited by this paper
• Efficacy of metabolites of a Streptomyces strain (AS1) to control growth and mycotoxin production by Penicillium verrucosum, Fusarium verticillioides and Aspergillus fumigatus in culture

  2020cited by this paper
• Modelling the effect of temperature and water activity on the growth rate of Aspergillus flavus and aflatoxin production in peanut meal extract agar.

  2020influential reference
• Comparative study on the effect of temperature and water activity on Aspergillus flavus and Aspergillus carbonarius isolates growth and mycotoxin production on a chili powder medium

  2020cited by this paper
• Influence of Light and Water Activity on Growth and Mycotoxin Formation of Selected Isolates of Aspergillus flavus and Aspergillus parasiticus

  2020cited by this paper
• Application of data mining techniques to predict the production of aflatoxin B1 in dry-cured ham

  2020cited by this paper
• Microrisk Lab: An Online Freeware for Predictive Microbiology

  2020cited by this paper
• Assessment of the Effect of Satureja montana and Origanum virens Essential Oils on Aspergillus flavus Growth and Aflatoxin Production at Different Water Activities

  2020cited by this paper
• Impact of some environmental factors on growth and ochratoxin A production by Aspergillus niger and Aspergillus welwitschiae.

  2019influential reference
• The dual role of oxalic acid on the resistance of tomato against Botrytis cinerea

  2019influential reference
• Assessment of mycotoxins co‐occurrence in Italian dried figs and in dried figs‐based products

  2018cited by this paper
• Assessment of Detoxification Efficacy of Irradiation on Zearalenone Mycotoxin in Various Fruit Juices by Response Surface Methodology and Elucidation of Its in-vitro Toxicity

  2018cited by this paper
• Assessment of intraspecies variability in fungal growth initiation of Aspergillus flavus and aflatoxin B1 production under static and changing temperature levels using different initial conidial inoculum levels.

  2018cited by this paper
• Use of efficient drying methods to improve the safety and quality of dried fig

  2018influential reference
• Rapid Alert System for Food and Feed: the semicarbazide notifications.

  2018cited by this paper
• Modelling the effect of temperature, pH, water activity, and organic acids on the germination time of Penicillium camemberti and Penicillium roqueforti conidia.

  2017cited by this paper
• Description of Aspergillus flavus growth under the influence of different factors (water activity, incubation temperature, protein and fat concentration, pH, and cinnamon essential oil concentration) by kinetic, probability of growth, and time-to-detection models.

  2017influential reference
• Single vs multiple-spore inoculum effect on growth kinetic parameters and modeled probabilities of growth and aflatoxin B1 production of Aspergillus flavus on pistachio extract agar.

  2017cited by this paper
• Interactions between water activity and temperature on the Aspergillus flavus transcriptome and aflatoxin B1 production.

  2017cited by this paper
• Use of predictive model to describe sporicidal and cell viability efficacy of betel leaf (Piper betle L.) essential oil on Aspergillus flavus and Penicillium expansum and its antifungal activity in raw apple juice

  2017cited by this paper
• Modelling the Probability of Growth and Aflatoxin B1 Production of Aspergillus Flavus under Changing Temperature Conditions in Pistachio Nuts

  2016cited by this paper
• Variation in Fumonisin and Ochratoxin Production Associated with Differences in Biosynthetic Gene Content in Aspergillus niger and A. welwitschiae Isolates from Multiple Crop and Geographic Origins

  2016cited by this paper
• Pre-harvest application of oxalic acid increases quality and resistance to Penicillium expansum in kiwifruit during postharvest storage.

  2016cited by this paper
• Mycotoxin production and predictive modelling kinetics on the growth of Aspergillus flavus and Aspergillus parasiticus isolates in whole black peppercorns (Piper nigrum L).

  2016cited by this paper
• Effect of temperature and water activity on gene expression and aflatoxin biosynthesis in Aspergillus flavus on almond medium.

  2016influential reference
• Susceptibility of Aspergillus spp. to acetic and sorbic acids based on pH and effect of sub-inhibitory doses of sorbic acid on ochratoxin A production

  2016cited by this paper
• CONTROL OF OCHRATOXIN A-PRODUCING FUNGI IN GRAPE BERRY BY MICROBIAL ANTAGONISTS: A REVIEW

  2016cited by this paper
• Modeling postharvest mycotoxins in foods: recent research

  2016cited by this paper
• Modelling the effect of essential oil of betel leaf (Piper betle L.) on germination, growth, and apparent lag time of Penicillium expansum on semi-synthetic media.

  2015cited by this paper
• Modelling the influence of temperature, water activity and sodium metabisulphite on the growth and OTA production of Aspergillus carbonarius isolated from Greek wine grapes.

  2015cited by this paper
• Effect of phenylpyrrole-resistance on fitness parameters and ochratoxin production in Aspergillus carbonarius.

  2013cited by this paper
• Comparison of growth, nutritional utilisation patterns, and niche overlap indices of toxigenic and atoxigenic Aspergillus flavus strains.

  2013cited by this paper
• Mycoflora and natural occurrence of aflatoxin, cyclopiazonic acid, fumonisin and ochratoxin A in dried figs

  2012cited by this paper
• Toxigenic fungi and mycotoxin associated with figs in the Mediterranean area.

  2012cited by this paper
• Rapid throughput analysis of filamentous fungal growth using turbidimetric measurements with the Bioscreen C: a tool for screening antifungal compounds.

  2012influential reference
• Growth curve prediction from optical density data.

  2012cited by this paper
• Aspergillus niger contains the cryptic phylogenetic species A. awamori.

  2011cited by this paper
• The application of transcriptomics to understand the ecological reasons of ochratoxin a biosynthesis by Penicillium nordicum on sodium chloride rich dry cured foods

  2011cited by this paper
• Growth and aflatoxin production of an Italian strain of Aspergillus flavus: influence of ecological factors and nutritional substrates

  2011cited by this paper
• Modelling the effect of temperature and water activity in the growth boundaries of Aspergillus ochraceus and Aspergillus parasiticus.

  2011cited by this paper
• Occurrence of Mould Counts and Aspergillus Species in Iranian Dried Figs at Different Stages of Production and Processing

  2010cited by this paper
• Effect of pH, water activity and temperature on the growth and accumulation of ochratoxin A produced by three strains of Aspergillus carbonarius isolated from Italian vineyards

  2010cited by this paper
• Effect of yeast antagonist in combination with heat treatment on postharvest blue mold decay and Rhizopus decay of peaches.

  2007cited by this paper
• Basis of predictive mycology.

  2005cited by this paper
• Oxalic Acid as a Fungal Acaracidal Virulence Factor

  2005cited by this paper
• Growth of and aflatoxin production by Aspergillus flavus in peanuts stored under modified atmosphere packaging (MAP) conditions.

  1994cited by this paper
• Control of growth and aflatoxin production of Aspergillus flavus under modified atmosphere packaging (MAP) conditions

  1993cited by this paper
• Impact of water management and geographic location on the physicochemical traits and fungal population of ‘Calabacita’ dried figs in Extremadura (Spain)

  year unknowncited by this paper

• No citing papers are available for this paper.