Production of dual layer antibacterial and antioxidant nanofibers by electrospinning method, characterization of the nanofibers and their potential for use in food applications research

The aim of the thesis study is to produce dual layer nanofiber (Nf) with antibacterial and antioxidant properties, to characterize and to show the potential of Nf for food applications. For nanofiber production purpose, Polycaprolactone (PCL) and Hydroxypropyl Beta Cyclodextrin (HPβ-CD) polymers which do not have cytotoxic effects, and have proven biodegradability were used. Nisin, which is in the GRAS class, was used to show effective antibacterial properties of nanofibers, and Black Cumin (BC) oil was used for antioxidant effect. Firstly, nanofibers which obtained BC and Nisin were produced. After that, PCL_BC_HPβ-CD_Nisin-Nf was produced by using the Dual spin method and the morphological structure of Nfs was evaluated by Scanning Electron Microscopy (SEM). Antibacterial effect of dual Nf against S. aureus was evaluated with disc diffusion analysis and the inhibition zone diameter was measured 3.1± 0.36 cm. In addition, the antioxidant effect of the produced Nf was examined and found that dual nanofiber had an antioxidant effect of 52.99%. The antibacterial and antioxidant properties of dual layer nanofibers were examined after long storage period. At the end of 60 days storage period, dual Nf's protected their antibacterial effect with 3.4 ± 0.2 cm inhibition zone against S. aureus. In addition, dual Nf's preserved its antioxidant effect at the of 7 days storage period. In the last part of the thesis study, Nf was used for the strawberry experiments for 22 days storage. Results showed that while strawberries began to spoilage in control group, Nf's protected freshness of the strawberries. The produced nanofibers with antibacterial and antioxidant properties could serve as a food coating or packaging.