Globalization and consumer awareness are rapidly pushing the food preservation and packaging industry towards the environment and health less harmful natural sources of antimicrobial materials and additives. One of the most successful biodegradable material is based on polylactic acid foil. The foil itself does not have any antimicrobial effect, therefore various antimicrobial and antioxidant polymers are added for functionality improvement. Chitosan is one of the extensively used polymer additives due to its effective mechanical and physicochemical properties. To improve its antimicrobial activity, bioactive substances such as essential oils or extracts of algae and plants are added. Within our work we tested antifungal activity against the Aspergillus flavus with various forms of chitosan coatings (with primary and quaternary chitosan formulations and encapsulated extract of brown algae Padina pavonica. Throughout the experiment, we determined antimicrobial and antioxidant activity of four different foil coating formulations by ISO 22196 method. Experimental results revealed better antimicrobial and antioxidant effect in samples with quaternary chitosan used for algae extract encapsulation (69,91 % and 69,12 % activity). Formulations with primary chitosan for encapsulation expressed 45,25 and 40,34 % activity, recpectively. Antioxidant test showed significant difference only in formulation where quaternary chitosan was used in base coating as well as for extract encapsulation (25,22 % SA). Other formulations showed slight antioxidant activity, which was not statisticaly significant (16,48 %, 14,05 % and 13,38 % SA, respectively).
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