Unveiling the effect of interacting forecasted abiotic factors on growth and aflatoxin B1 production kinetics by Aspergillus flavus

Esther Garcia-Cela; Carol Verheecke-Vaessen; Maria Gutierrez-Pozo; Elisavet Kiaitsi; Alessandra M Gasperini; Naresh Magan; Angel Medina

doi:10.1016/j.funbio.2020.05.003

Unveiling the effect of interacting forecasted abiotic factors on growth and aflatoxin B₁ production kinetics by Aspergillus flavus

Fungal Biol. 2021 Feb;125(2):89-94. doi: 10.1016/j.funbio.2020.05.003. Epub 2020 May 30.

Authors

Esther Garcia-Cela¹, Carol Verheecke-Vaessen², Maria Gutierrez-Pozo³, Elisavet Kiaitsi², Alessandra M Gasperini², Naresh Magan², Angel Medina⁴

Affiliations

¹ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds, MK43 0AL, UK; Biological and Environmental Sciences, School of Life and Medical Sciences, University of Hertfordshire, Hatfield, AL109AB, UK.
² Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds, MK43 0AL, UK.
³ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds, MK43 0AL, UK; Surface Engineering and Precision Institute, Cranfield University, Cranfield, Beds, MK43 0AL, UK.
⁴ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds, MK43 0AL, UK. Electronic address: a.medinavaya@cranfield.ac.uk.

PMID: 33518209
DOI: 10.1016/j.funbio.2020.05.003

Abstract

The aim was to decipher the temporal impact of key interacting climate change (CC) abiotic factors of temperature (30 vs 37 °C), water activity (a_w; 0.985 vs 0.930) and CO₂ exposure (400 vs 1000 ppm) on (a) growth of Aspergillus flavus and effects on (b) gene expression of a structural (aflD) and key regulatory gene (aflR) involved in aflatoxin B₁ (AFB₁) biosynthesis and (c) AFB₁ production on a yeast extract sucrose medium over a period of 10 days. A. flavus grew and produced AFB₁ very early with toxin detected after only 48 h. Both growth and toxin production were significantly impacted by the interacting abiotic factors. The relative expression of the aflD gene was significantly influenced by temperature; aflR gene expression was mainly modulated by time. However, no clear relationship was observed for both genes with AFB₁ production over the experimental time frame. The optimum temperature for AFB₁ production was 30 °C. Maximum AFB₁ production occurred between days 4-8. Exposure to higher CO₂ conditions simulating forecasted CC conditions resulted in the amount of AFB₁ produced in elevated temperature (37 °C) being higher than with the optimum temperature (30 °C) showing a potential for increased risk for human/animal health due to higher accumulation of this toxin.

Keywords: Elevated CO(2); Mycotoxins; Toxin gene expression; Water activity; aflD; aflR.

MeSH terms

Aflatoxin B1* / genetics
Aflatoxin B1* / metabolism
Aspergillus flavus* / genetics
Aspergillus flavus* / metabolism
Gene Expression Regulation, Fungal
Genes, Regulator
Kinetics
Temperature*

Substances

Aflatoxin B1