The efficacy of essential oil components loaded into montmorillonite against Aspergillus niger and Staphylococcus aureus

Abstract Essential oil components ( EOC s) are potent natural antimicrobial agents, but their high volatility and reactivity limit their potential applications. Here, we report the preparation of a series of nanomaterials containing EOC s (i.e., allyl isothiocyanate, carvacrol, cinnamaldehyde, diallyl disulphide, eugenol and thymol). The materials were prepared by simple adsorption of the EOC s onto a montmorillonite nanoclay. The antimicrobial activities of these materials were assessed against Aspergillus niger and Staphylococcus aureus as typical models of agricultural fungal pathogens and foodborne bacterial pathogens, respectively. In addition, the activities of the encapsulated EOC s were compared with those of the corresponding free forms with or without Tween‐80 in two types of assays: microdilution assays for determining the minimum inhibitory concentration ( MIC ) and agar‐based assays mimicking surface treatment. Enhanced antifungal activity of the encapsulated form was observed for all EOC s. In addition, against S. aureus , the MIC s of all EOC s were remarkably lower in encapsulated form than in free form. These results indicate that EOC s encapsulated in low‐cost nanoclays have favourable potential as antimicrobials compared with the pure compounds.