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Essential oil components (EOCs) 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 EOCs (i.e., allyl isothiocyanate, carvacrol, cinnamaldehyde, diallyl disulphide, eugenol and thymol). The materials were prepared by simple adsorption of the EOCs 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 EOCs 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 EOCs. In addition, against S. aureus, the MICs of all EOCs were remarkably lower in encapsulated form than in free form. These results indicate that EOCs encapsulated in low‐cost nanoclays have favourable potential as antimicrobials compared with the pure compounds. Antimicrobial activity of the nanoclay‐encapsulated essential oil components were compared with their free forms. Prolonged activity of the encapsulated forms was observed against Aspergillus niger, while remarkably lower MICs were achieved against S. aureus. [ABSTRACT FROM AUTHOR]

A number of liverwort species are known to emit volatile terpenoids and simple aromatic compounds when crushed. The characteristic odour of these spore-forming plants is associated with oil body constituents. Secondary metabolites, which constitute the oil bodies, are also of value for taxonomic investigations. Liverworts have yielded a rich array of secondary metabolites. Many of these compounds are characterized by unique structures, and some of them have not been found in any other plants, fungi, or marine organisms. Gas chromatographic profiling of the volatile extracts obtained from the liverworts has been applied with success in differentiating liverworts species, and also used to resolve the taxonomic problems at genus and family level. Due to the fact that liverworts are morphologically very small and it is difficult to collect a sufficient amount of plant material, there are few research data on the composition of the essential oils obtained from these plants. Nevertheless, the available data indicate that, as in the case of aromatic plants, the components present in essential oils obtained from the liverworts can be used in chemosystematic studies of this plant group. The aim of this paper is to show whether: (i) there are differences in the essential oils composition between different liverwort species; (ii) it is possible to find chemical markers characteristic for the analysed liverwort species; and (iii) the data derived from an analysis of the essential oils are in accordance with the data received from volatile extracts. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]