Synthetic antimicrobial agents inhibit aflatoxin production

Area of Science:

• Microbiology
• Mycology
• Biochemistry

Background:

• Antimicrobial peptides (AMPs) are known for bacterial membrane disruption.
• The impact of AMPs on filamentous fungi, particularly Aspergillus flavus, remains underexplored.
• Aflatoxins produced by A. flavus pose significant risks to food safety and human health.

Purpose of the Study:

• To synthesize novel small molecular polypeptides using an economical heat conjugation method.
• To investigate the effects of these synthesized polypeptides on the growth and secondary metabolism of Aspergillus flavus.
• To evaluate the potential of these antimicrobial agents as a strategy for controlling aflatoxin contamination.

Main Methods:

• Synthesis of small molecular polypeptides via heat conjugation.
• Assessing the impact of polypeptides on A. flavus growth parameters: aflatoxin production, conidiation, and sclerotia formation.
• Analyzing the effects on aflatoxin structural gene expression and intracellular reactive oxygen species (ROS) levels.
• Evaluating membrane permeability changes and safety for mammalian cells.

Main Results:

• The synthesized antimicrobial agents significantly inhibited aflatoxin production, conidiation, and sclerotia formation in A. flavus.
• Gene expression of aflatoxin biosynthesis was notably suppressed.
• Intracellular ROS levels were reduced in A. flavus treated with the agents.
• The agents altered membrane permeability and demonstrated safety for mammalian cells.

Conclusions:

• The synthesized antimicrobial agents effectively inhibit key growth and toxic metabolite production pathways in Aspergillus flavus.
• These agents represent a potential new generation of safe and effective tools for controlling aflatoxin contamination.
• The findings suggest a viable approach to mitigate risks associated with aflatoxin in agricultural products.