Removal of Alternaria mycotoxins from aqueous solution by inactivated yeast powder

J Sci Food Agric. 2020 Nov;100(14):5182-5190. doi: 10.1002/jsfa.10567. Epub 2020 Jul 10.

Abstract

Background: Alternariol (AOH) and alternariol monomethyl ether (AME), produced by Alternaria spp., are the two mycotoxins with the highest outbreak rates in food systems. The purpose of this study was to investigate the removal of AOH and AME from aqueous solutions by inactivated yeast cells. The effects of strains, yeast powder amount, temperature, and pH were evaluated. The kinetics of AOH and AME adsorption on inactivated yeast cells was fitted with four models and a release assay was carried out.

Results: All three tested yeasts could remove AOH and AME. GIM 2.119 was the most effective strain. The reduction rate of both AOH and AME could be as much as 100% with 40 g‧L-1 of yeast powder. For both mycotoxins, pH = 9 was the best environment for toxin removal. The pseudo-second-order kinetic model was the best model, with R2 ranging from 0.989 to 0.999. However, the R2 of the pseudo-first-order and Elovich models was also relatively high. Alternariol and AME could be partially eluted by methanol and acetonitrile.

Conclusion: The inactivated yeast cells could effectively remove AOH and AME. This was best fitted by the pseudo-second-order model. The release assay suggested that the adsorption of Alternaria mycotoxins was partially reversible. The results of this study provide a theoretical basis for the removal of Alternaria mycotoxins from food systems and are useful for the investigation of the mechanisms involved in mycotoxin adsorption by inactivated yeast cells. © 2020 Society of Chemical Industry.

Keywords: AME; AOH; Alternaria mycotoxins; yeast.

MeSH terms

  • Adsorption
  • Alternaria / metabolism*
  • Food Contamination / analysis
  • Lactones / chemistry
  • Mycotoxins / chemistry*
  • Mycotoxins / metabolism
  • Saccharomyces cerevisiae / chemistry*
  • Yeast, Dried / chemistry

Substances

  • Lactones
  • Mycotoxins
  • alternariol
  • alternariol monomethyl ether