Fabrication, performance and curcumin-controlled release of electrospun sarcoplasmic protein nanofiber films via layer-by-layer self-assembly

Abstract

The recycling and high-value application of fish sarcoplasmic protein (FSP) from the surimi rinsing wastewater can promote the sustainable development. This work successfully fabricated monolayer nanofiber films and three-layer nanofiber films with cellulose acetate (CA) nanofibers as the outer layer to encapsulate curcumin (CUR) based on chitosan flocculated and direct freeze-dried FSP (CFSP and DFSP) through electrospinning and layer-by-layer (LBL) self-assembly, and investigated the films microstructure, performance and CUR release behavior. The nanofibers exhibited uniform, smooth, and beadless morphology, with a clear interface but strong interactions between the adjacent layers for three-layer films. The CA-CFSP/CUR-CA three-layer film possessed the best flexibility (elongation at break 6.5%), surface hydrophobicity (water contact angle 130.5° ± 2.6°) and thermal stability, suggesting its potential application in food packaging. The CUR release kinetics in all nanofiber films well fitted to First-order model, reflecting a release driven by concentration gradient. The monolayer films quickly released CUR in neutral PBS. The CA-DFSP/CUR-CA three-layer film could resist gastric acid and controllably released ∼18% CUR in the first 60 min and cumulatively up to 45.2% within 480 min, following diffusion-controlled Fickian release in simulated gastric-intestinal fluid (SGF-SIF), implying great applications potential in sustained release. This study can not only advance the surimi processing field by recovering and utilizing FSP from the surimi rinsing wastewater, but also expand the application of FSP for food packaging and drug delivery fields.