Development of antifungal electrospun nanofiber mats containing Meyerozyma caribbica

To mitigate vegetable and fruit loss caused by post-harvest fungal diseases, polymeric antifungal coatings encapsulating biocontrol yeasts offer a sustainable alternative. Nanofibers derived from pullulan, cashew gum, FucoPol and poly (ethylene oxide) (PEO), were electrospun and loaded with Meyerozyma caribbica (GenBank ID: JQ398674). The morphological, thermal and chemical properties of cashew gum (CG:PEO), FucoPol (FP:PEO), and pullulan nanofibers were characterized. The viability of M. caribbica within the fibers and their in vitro antifungal activity against six phytopathogens were assessed. Morphological analysis exhibited the presence of nanofibers encapsulating M. caribbica. ATR-FTIR spectroscopy identified the absence of interactions between the yeast and polymers. Fibers containing M. caribbica exhibited in vitro fungistatic effects on spore germination. Pullulan nanofibers showed the highest M. caribbica viability and the highest percentage of growth inhibition against the evaluated fungi. These promising nanofibers encapsulating biocontrol yeasts could be used as edible coatings or agricultural aids, which offer an alternative for post-harvest treatment to control fungal diseases, reducing global food loss.This work was supported by the CYTED thematic network (code 319RT0576), the Agencia Valenciana de Innovación (AVI), projects INNEST/2022/25 and AGROALNEXT/2022/058, the grant PID2021-128749OB-C31 funded by MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe.Peer reviewe