LAUSR

Abstract The main drawback of gelatin nano and sub-micron fibers for delivery of lipophilic compounds such as lycopene is its quick dissolving in the oral phase. Herein, electrospinning is used to design a multilayer sandwich structure to enhance the bioaccessibility of lycopene in the target site, small intestine. For this purpose, the gelatin layers loaded with 0.05 and 0.075% (w/w) lycopene were sandwiched between the two layers of the hydrophobic electrospun proteins of zein. The rheological, physicochemical and bioaccessibility properties of the designed solutions and spun samples were comprehensively studied. The most favorable conditions for electrospinning of each layer were selected and judged by the morphological, fiber diameter distributions, production efficiency and particularly higher protection of lycopene. The encapsulation efficiencies of lycopene for the sandwich samples were measured between 83.97 and 90.51% which is in a highly acceptable level. The FTIR and DSC analyses confirmed the presence of lycopene, suggested its chemical or physicochemical interactions with protein. The improvement in the thermal resistance of encapsulated lycopene was also confirmed by DSC experiment. The release behavior of lycopene was evaluated by Kopcha, Peppas-Sahlin and Korsmeyer-Peppas models in the simulated digestive environments whereby a Fickian diffusion assisted with matrix erosion was observed. The fast and higher release of lycopene in the small intestine phase was also seen, so that the highest bioaccessibility reached to the 16.44% for the multilayered sample loaded with 0.075% (w/w) lycopene. These findings show a promising approach for designing safe delivery systems based on electrospun fibers with higher bioaccessibility for lipophilic compounds.