Combined suppression of Aspergillus parasiticus and aflatoxin B1 in marinades: unraveling the cooperative antifungal mechanism of linalool and surfactin

Dual inhibition of fungal growth and toxin production in marinated food systems. • Linalool-surfactin completely inhibits A. parasiticus growth and AFB 1 synthesis. • The synergy disrupts fungal cell membrane integrity and inhibits ATP synthesis. • Metabolomics reveals disruptions in cell cycle, energy, and amino acid metabolism. • Provides a theoretical basis for green control of AFB 1 in food processing/storage. This study aimed to control mycotoxigenic fungi in repeatedly used marinades and marinated foods and to elucidate the cooperative mechanism of linalool and surfactin against Aspergillus parasiticus growth and aflatoxin B 1 (AFB 1 ) synthesis by analyzing the changes in mycelial growth, AFB 1 content, ATP synthesis, and metabolites. Results showed that linalool inhibited A. parasiticus growth more effectively than surfactin, while their combination exhibited a strong cooperative effect, completely suppressing mycelial growth and AFB 1 synthesis at high doses. The linalool-surfactin combination effectively disrupted cell membrane integrity, reduced ATP synthesis, increased malondialdehyde content to 18.86 nmol/g, and decreased ATPase activity by 80.64%. Metabolomic analysis showed that the linalool-surfactin combination disrupted glucose metabolism and the tricarboxylic acid cycle, leading to the abnormal accumulation of metabolites such as glucose-6-phosphate and malic acid. Moreover, the combination induced abnormal expression of key metabolites such as L-glutamic acid, 3-sulfinylpyruvic acid, and cyclic adenosine monophosphate, disrupting pathways including amino acid metabolism, oxidative phosphorylation, and the cell cycle, thereby inhibiting the growth and toxin synthesis of A. parasiticus at multiple levels. This multi-level inhibition via membrane damage, energy disruption, and metabolic dysregulation provides a mechanistic basis for natural preservation strategies to control AFB 1 in marinade-based systems and marinated products. Download: Download high-res image (254KB) Download: Download full-size image