Bioactive pectic polysaccharides from bay tree pruning waste: Sequential subcritical water extraction and application in active food packaging

The potential isolation of bio-active polysaccharides from bay tree pruning waste was studied using sequential subcritical water extraction using different time-temperature combinations. The extracted polysaccharides were highly enriched in pectins while preserving their high molecular mass (10–100 kDa), presenting ideal properties for its application as additive in food packaging. Pectin-enriched chitosan films were prepared, improving the optical properties (≥95% UV-light barrier capacity), antioxidant capacity (˃95% radical scavenging activity) and water vapor permeability (≤14 g·Pa−1·s−1·m−1·10−7) in comparison with neat chitosan-based films. Furthermore, the antimicrobial activity of chitosan was maintained in the hybrid films. Addition of 10% of pectins improved mechanical properties, increasing the Young's modulus 12%, and the stress resistance in 51%. The application of pectin-rich fractions from bay tree pruning waste as an additive in active food packaging applications, with triple action as antioxidant, barrier, and antimicrobial has been demonstrated. [Display omitted] •Bioactive pectic polysaccharides from bay tree pruning waste (BTPW)•BTPW-pectins preserved their high molecular weight by subcritical water extraction.•Pectin-enriched chitosan films exhibited antioxidant and antimicrobial properties.•Bioactive films showed interesting water vapor and UV-light barrier properties.•Biobased films made of chitosan and pectins can be used for food packaging applications.