Carbon dioxide production as an indicator of Aspergillus flavus colonisation and aflatoxins/cyclopiazonic acid contamination in shelled peanuts stored under different interacting abiotic factors

E Garcia-Cela; F J Gari Sanchez; M Sulyok; C Verheecke-Vaessen; A Medina; R Krska; N Magan

doi:10.1016/j.funbio.2019.10.003

Carbon dioxide production as an indicator of Aspergillus flavus colonisation and aflatoxins/cyclopiazonic acid contamination in shelled peanuts stored under different interacting abiotic factors

Fungal Biol. 2020 Jan;124(1):1-7. doi: 10.1016/j.funbio.2019.10.003. Epub 2019 Oct 24.

Authors

E Garcia-Cela¹, F J Gari Sanchez², M Sulyok³, C Verheecke-Vaessen⁴, A Medina⁵, R Krska⁶, N Magan⁷

Affiliations

¹ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds., MK43 AL5, UK. Electronic address: m.e.garcia-cela@cranfield.ac.uk.
² Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds., MK43 AL5, UK. Electronic address: arelgar17@gmail.com.
³ Institute of Bioanalytics and Agro-Metabolomics, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna, Konrad Lorenzstr. 20, A-3430 Tulln, Austria. Electronic address: michael.sulyok@boku.ac.at.
⁴ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds., MK43 AL5, UK. Electronic address: C.Verheecke@cranfield.ac.uk.
⁵ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds., MK43 AL5, UK. Electronic address: a.medinavaya@cranfield.ac.uk.
⁶ Institute of Bioanalytics and Agro-Metabolomics, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna, Konrad Lorenzstr. 20, A-3430 Tulln, Austria. Electronic address: rudolf.krska@boku.ac.at.
⁷ Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Beds., MK43 AL5, UK. Electronic address: n.magan@cranfield.ac.uk.

PMID: 31892372
DOI: 10.1016/j.funbio.2019.10.003

Abstract

Aspergillus flavus is the main xerophylic species colonising stored peanuts resulting in contamination with aflatoxins (AFs) and cyclopiazonic acid (CPA). This study evaluated the relationship between storage of shelled peanuts under interacting abiotic conditions on (a) temporal respiration (R) and cumulative CO₂ production, (b) dry matter losses (DMLs) and (c) aflatoxin B₁ (AFB₁) and CPA accumulation. Both naturally contaminated peanuts and those inoculated with A. flavus were stored for 7-days under different water activities (a_w; 0.77-0.95) and temperatures (20-35°C). There was an increase in the temporal CO₂ production rates in wetter and warmer conditions, with the highest respiration at 0.95 a_w + A. flavus inoculum at 30°C (2474 mg CO₂kg^-1h^-1). The DMLs were modelled to produce contour maps of the environmental conditions resulting in maximum/minimum losses. Maximum mycotoxin contamination was always at 0.95 a_w although optimal temperatures were 25-30°C for AFs and 30-35°C for CPA. These results showed a correlation between CO₂ production and mycotoxin accumulation. They also provide valuable information for the creation of a database focused on the development of a post-harvest decision support system to determine the relative risks of contamination with these mycotoxins in stored shelled peanuts.

Keywords: Dry matter losses; Food safety; Groundnuts; Mycotoxins; Temperature; Water activity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aflatoxin B1 / analysis
Aflatoxin B1 / biosynthesis
Arachis / microbiology*
Aspergillus flavus / growth & development*
Aspergillus flavus / metabolism*
Carbon Dioxide / metabolism*
Food Microbiology
Food Storage*
Indoles / analysis
Indoles / metabolism
Mycotoxins / analysis*
Mycotoxins / biosynthesis
Temperature
Water

Substances

Indoles
Mycotoxins
Water
Carbon Dioxide
Aflatoxin B1
cyclopiazonic acid