Fungistatic Films Containing Cinnamon Essential Oil: New Coatings to Preserve the Nutraceutical Content of Avocado Fruit against Fusariosis

Avocadoes are a rich source of nutrients and nutraceuticals that preserve human health. Nevertheless, this fruit is susceptible to phytopathogen infection during the postharvest period causing severe economic losses. Herein, we report on the in situ antifungal assessment of biodegradable films impregnated with the essential oil of Cinnamomum verum (CvEO) as natural fungistatic coatings to extend postharvest quality of Hass avocadoes (Persea americana cv. Hass). These coatings were evaluated on fruits previously infected with a native strain of Fusarium verticillioides. The cytotoxic assessment of CvEO on F. verticillioides revealed a minimum inhibitory concentration of 0.3±0.0 g L⁻¹ whereas its chemical profiling showed (E)-cinnamaldehyde (45.9 %) 1,3,8-p-menthatriene (7.9 %) and linalool (6.8 %) as the major bioactive compounds. Four coatings (FC1–FC4) were made using chitosan (1 %) and a diverse quantity of CvEO (0.4–1.3 % w/v). The physicochemical properties demonstrated that the films FC3 and FC4 have the optimal characteristics of a food coating. Avocadoes preserved with the films FC3 and FC4 substantially kept (p<0.01) fruit firmness and the nutraceutical content of infected avocados at least for 21 d. The results of the present investigation suggest that our hybrid materials can conserve basic nutritional parameters such as fiber, protein, reducing sugars, as well as the content of unsaturated fatty acids which are the main nutraceuticals of this fruit.