Improving probiotic survivability using coaxial electrospinning: Role of ethyl cellulose in shell

To achieve the positive effects of probiotics, it is crucial to enhance their viability and stability throughout gastrointestinal tract. In the study, polyvinyl alcohol-fucoidan@ethyl cellulose (PVOH-FUC@EC) core-shell electrospun nanofibers with flow ratios of 1:1, 1:1.5 and 1:2 by coaxial electrospinning were developed to co-encapsulate Lactiplantibacillus plantarum 69-2 (LP69-2) and dihydromyricetin. The average diameter of PVOH-FUC@EC nanofibers decreased, while the shell thickness of PVOH-FUC@EC nanofibers increased as the shell solution flow ratios increased. Furthermore, the successful formation of core-shell structure of PVOH-FUC@EC nanofibers was verified by confocal laser scanning microscopy and transmission electron microscope. PVOH-FUC@EC nanofibers with higher shell flow rate presented superior thermal stability. Compared with uniaxial nanofibers, the antioxidant capacity of PVOH-FUC@EC core-shell nanofibers was significantly enhanced when core-shell flow ratio was 1:1 ( P  < 0.05). Moreover, the survival rate of LP69-2 embedded in PVOH-FUC@EC core-shell nanofibers was significantly elevated after simulated gastrointestinal digestion ( P  < 0.05). Overall, this study further revealed that EC-coated core-shell nanofibers was an effective and novel approach for co -delivering probiotics and polyphenols by coaxial electrospinning, thereby improving their efficacy in functional foods.