Synthetic antimicrobial agents inhibit aflatoxin production

Braz J Microbiol. 2021 Jun;52(2):821-835. doi: 10.1007/s42770-021-00423-4. Epub 2021 Jan 14.

Abstract

Antimicrobial peptides (AMPs) are biologically active molecules that can eradicate bacteria by destroying the bacterial membrane structure, causing the bacteria to rupture. However, little is known about the extent and effect of AMPs on filamentous fungi. In this study, we synthesized small molecular polypeptides by an inexpensive heat conjugation approach and examined their effects on the growth of Aspergillus flavus and its secondary metabolism. The antimicrobial agents significantly inhibited aflatoxin production, conidiation, and sclerotia formation in A. flavus. Furthermore, we found that the expression of aflatoxin structural genes was significantly inhibited, and the intracellular reactive oxygen species (ROS) level was reduced. Additionally, the antimicrobial agents can change membrane permeability. Overall, our results demonstrated that antimicrobial agents, safe to mammalian cells, have an obvious impact on aflatoxin production, which indicated that antimicrobial agents may be adopted as a new generation of potential agents for controlling aflatoxin contamination.

Keywords: Aflatoxin; Antimicrobial agents; Aspergillus flavus; Sclerotia.

MeSH terms

  • Aflatoxins / biosynthesis*
  • Antifungal Agents / chemical synthesis*
  • Antifungal Agents / pharmacology*
  • Aspergillus flavus / drug effects*
  • Aspergillus flavus / genetics
  • Aspergillus flavus / growth & development
  • Aspergillus flavus / metabolism
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Pore Forming Cytotoxic Proteins / chemical synthesis*
  • Pore Forming Cytotoxic Proteins / pharmacology*
  • Reactive Oxygen Species / metabolism
  • Secondary Metabolism
  • Spores, Fungal / drug effects
  • Spores, Fungal / genetics
  • Spores, Fungal / growth & development
  • Spores, Fungal / metabolism

Substances

  • Aflatoxins
  • Antifungal Agents
  • Fungal Proteins
  • Pore Forming Cytotoxic Proteins
  • Reactive Oxygen Species