Electrospun zein nanofibers as a nanocarrier of Eucalyptus essential oil: Characterization, and antimicrobial properties

Eucalyptus is an important medicinal plant that is widely used for its antimicrobial properties. The aim of this research was to fabricate electrospun nanofibers as nano carrier of eucalyptus essential oil, and to characterize them, and to study the antimicrobial properties of nanofibers against S. aureus and E. coli. Eucalyptus essential oil was mixed at different concentrations of 0%, 2.5%, 5%, and 10% in zein solution and electrospun zein nanofibers prepared by electrospinning process. GC-MS analysis was done to identify the components of the Ecalyptus essential oil. The electrospun zein nanofibers containing Eucalyptus essential oil were characterized by Scanning electron microscopy (SEM), Image J, Atomic force microscopy (AFM), X-ray diffraction (XRD), Differential scanning calorimetric (DSC), and Fourier transform infrared (FTIR). Disc diffusion method was used to study the antimicrobial properties of nanofibers. Results indicated that diameters of electrospun  zein nanofibers increased with increasing concentration of essential oil from 102 nm to 193 nm. XRD results determined that zein nanofibers were in amorphous structure. DSC results verified the existence of Eucalyptus essential oil in nanofibers. FTIR results indicated the interaction between Eucalyptus essential oil and zein. Antimicrobial results showed that the Eucalyptus essential oil loaded nanofibers were effective against both studied gram positive and gram negative bacteria. Therefore, Eucalyptus essential oil loaded nanofibers could be used as active packaging for variety of foods.