Chemico-physical and antifungal properties of poly(butylene succinate)/cavoxin blend: Study of a novel bioactive polymeric based system

This manuscript describes antifungal, structural, thermal and morphological properties of a novel, eco-friendly bioplastic film, based on poly(butylenesuccinate) and cavoxin, a chalcone phytopathogenic metabolite, isolated from cultures by the fungus Phoma cava and included inside the biodegradable polymeric matrix. The antagonistic activity of the film explored against two fungal food contaminants Penicilliumroqueforti and Aspergillusniger, highlighted that cavoxin was fungicide at MIC concentrations. The chemico-physical analysis were performed on films before and after antifungal activity. Thermal analysis evidenced both the higher thermal stability of poly (butylenesuccinate) and cavoxin blend and the sharp nucleating action of cavoxin on the polymer. Infrared spectroscopy highlighted the presence of physical interaction between the polar groups of the blend components, whereas gel permeation chromatography highlighted that the hydrolytic effect of cavoxin on poly(butylenesuccinate) was responsible for the diffusion and releasing of the biomolecule from the matrix and UV-Vis spectroscopy provided quantitative information of release kinetics. Finally, morphological analysis confirmed both the polymeric surface hydrolysis exerted by cavoxin, and the adhesion of fungal spores on films after contact occurred during the antifungal assay.