Self-assembled thymol-betaine co-crystals with controlled release and hygroscopic properties as green preservatives for aflatoxin prevention

Food Chem. 2024 Oct 30:456:140037. doi: 10.1016/j.foodchem.2024.140037. Epub 2024 Jun 8.

Abstract

Mycotoxins are representative contaminants causing food losses and food safety problems worldwide. Thymol can effectively inhibit pathogen infestation and aflatoxin accumulation during grain storage, but high volatility limits its application. Here, a thymol-betaine co-crystal system was synthesized through grinding-induced self-assembly. The THY-TMG co-crystal exhibited excellent thermal stability with melting point of 91.2 °C owing to abundant intermolecular interactions. Remarkably, after 15 days at 30 °C, the release rate of thymol from co-crystal was only 55%, far surpassing that of pure thymol. Notably, the co-crystal demonstrated the ability to bind H2O in the environment while controlling the release of thymol, essentially acting as a desiccant. Moreover, the co-crystals effectively inhibited the growth of Aspergillus flavus and the biosynthesis of aflatoxin B1. In practical terms, the THY-TMG co-crystal was successful in preventing AFB1 contamination and nutrients loss in peanuts, thereby prolonging their shelf-life under conditions of 28 °C and 70% RH.

Keywords: Aflatoxin B(1); Betaine; Co-crystal; Controlled release; Food preservation; Thymol.

MeSH terms

  • Aflatoxin B1 / chemistry
  • Aflatoxins / chemistry
  • Arachis / chemistry
  • Arachis / microbiology
  • Aspergillus flavus* / chemistry
  • Aspergillus flavus* / drug effects
  • Aspergillus flavus* / growth & development
  • Betaine* / chemistry
  • Betaine* / pharmacology
  • Crystallization
  • Delayed-Action Preparations / chemistry
  • Food Contamination / analysis
  • Food Contamination / prevention & control
  • Food Preservatives / chemistry
  • Food Preservatives / pharmacology
  • Thymol* / chemistry
  • Thymol* / pharmacology

Substances

  • Thymol
  • Betaine
  • Food Preservatives
  • Delayed-Action Preparations
  • Aflatoxins
  • Aflatoxin B1