Incorporation of essential oils into biopolymer films based on pumpkin oil cake in order to improve their antioxidant activity

Abstract

Active films based on pumpkin oil cake, with 1 % and 2 % of winter savory and basil essential oil, were synthesized in the paper, and the antioxidant activity of the films obtained was subsequently examined. A biopolymer film based on pumpkin oil cake without the addition of essential oils was used as a control. The following methods were used for determining the antioxidant activity of the films: the DPPH radical scavenging activity, the hydroxyl radical scavenging activity and the reducing power assay. The control film showed some antioxidant activity (DPPH radical scavenging activity = 61 %, hydroxyl radical scavenging activity = 33 %, reducing power = 0.534). However, the addition of essential oils increased the antioxidant activity of the films, especially their reducing power, where as the film with 2 % of winter savory essential oil exhibited the highest activity. A slight increase in the DPPH radical and the hydroxyl radical scavenging activities was also observed with the incorporation of essential oils into the experimental films.

Keywords

• biopolymer films
• pumpkin oil cake
• essential oils
• winter savory
• basil
• antioxidant activity