Application of ZnO Nanoparticles Phycosynthesized with Ulva fasciata Extract for Preserving Peeled Shrimp Quality.

Zinc oxide nanoparticles (ZnONPs) were the targets of numerous biological syntheses to attain their precious values in various biomedical fields. The phycosynthesis of ZnONPs were innovatively investigated using cell-free extract of the macroalgae, Ulva fasciata Delile. The phycosynthesized U. fasciata-zinc oxide nanoparticles (UFD-ZnONPs) had 77.81 nm mean size, with flower and sphere shapes and positive zeta potential. The UFD-ZnONPs infra-red analysis indicated their basic components' cross-linkage. The antibacterial potentialities of UFD-ZnONPs were confirmed, qualitatively and quantitatively, against foodborne microorganisms (Escherichia coli plus Staphylococcus aureus); the bactericidal action was higher for UFD-ZnONPs than the annealed phycosynthesized ZnONPs. The scanning micrographs of S. aureus and E. coli cells treated with UFD-ZnONPs indicated the severe action of nanoparticles to destroy bacterial cells in time-dependent manners. Peeled shrimps (Fenneropenaeus indicus) were biopreservated through refrigerated storage (4 °C) with UFD-ZnONPs based solution for six days. The microbial examination of UFD-ZnONPs -treated shrimps displayed decrease in microbial loads throughout the storage days. Moreover, the UFD-ZnONPs-treated shrimps showed acceptable sensorial attributes (appearance, odor, color and texture) compared to untreated shrimps. UFD-ZnONPs nanocomposite concentration of 3% and 5% could be remarkably suggested as efficient procedure for shrimps' biopreservation during refrigerated storage regarding sensorial quality and microbial profile of product.