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In this study, rosemary essential oil was encapsulated in zeinelectrospun fibers at different concentrations of loading (0%, 2.5%, 5%, and 10% v/v). The chemical composition of rosemary essential oil was determined by GC-MS. The resultant zein-electrospun fibers were characterized by SEM, AFM, XRD, DSC, FTIR, and NMR. After being loaded with the essential oil, the fibers were evaluated for antimicrobial properties by the disc diffusion method against S. aureus (ATCC 1112) and E. coli (ATCC 1330). The release test was studied at pH values of 3 and 7.2 in phosphate buffer for 180 min. The GC-MS indicated that α-pinene occurred as a major compound in rosemary essential oil. Diameters of the zein-electrospun fibers increased in response to higher concentrations of rosemary essential oil. The AFM assay attributed a tubular morphology to the fibers. The physical status of rosemary essential oil in zein-electrospun fibers was determined by X-ray diffraction (XRD). DSC thermograms and FTIR spectra confirmed the existence of the rosemary essential oil in zein-electrospun fibers. FTIR spectra also indicated that adding rosemary essential oil to the fibers affected the secondary structure of zein protein. The NMR study showed that the electrospinning process did not change the secondary structure of zein. Disc diffusion indicated that zein-electrospun mats generated inhibition zones against S. aureus and E. coli. The release test revealed that pH values significantly affect the release of rosemary essential oil from fibers. The results demonstrated how loading zein-electrospun fibers with rosemary essential oil can benefit food packaging. Practical Application: In this study, electrospun fibers were produced from food-grade biopolymer to encapsulate rosemary essential oil. This product can be produced at industrial scale as an active food packaging/coating, controlled release, and delivery of the rosemary essential oil to food products and gastrointestinal. Also, it can be considered as a functional food to increase health.

In this study, ascorbyl palmitate was encapsulated in electrospun zein fibers at different loading levels (2.5%w/v, 5%w/v and 10% w/v). HPLC, SEM, FTIR, XRD, DSC and BET characterized the resulting electrospun zein fibers containing ascorbyl palmitate. Results indicated that the diameters of electrospun zein fibers increased with increasing concentration of ascorbyl palmitate. The physical status of ascorbyl palmitate in electrospun zein fibers was determined by X-ray diffraction (XRD), and differential scanning calorimetry (DSC). Fourier transform infrared (FTIR) was used to study the interaction between ascorbyl palmitate, and zein. The results showed that there was hydrogen bonding between protein and ascorbyl palmitate. Pore size was characterized by N 2 adsorption-desorption isotherms. Contact angle results showed that hydrophobicity of electrospun fiber mats was not affected by ascorbyl palmitate. Encapsulation efficiency of ascorbyl palmitate in electrospun zein fibers was about 22.5-65.5% w/v. Release study results indicated that pH and morphology affected the release. This is the first report describing that ascorbyl palmitate was successfully encapsulated in electrospun zein fibers. This product is intended to be used as an active coating for the delivery of ascorbyl palmitate to butter and other food products.

Artemisia is an important medicinal plant which is widely used in the treatment of skin diseases and it has antimicrobial properties. This research was carried out with the aim of making nano-fibers with Artemisia sieberi Besser extract to study its antimicrobial properties against Pseudomonas aeruginosa and Staphylococcus aureus bacteria. Artemisia extract and electrospinning solution containing 0.2 g of polyethylene oxide, 0.05 g of chitosan and 1.5 ml of acetic acid were prepared and then nanofibers were produced by electrospinning of the solutions. Artemisia Extract loading with 100 mg/ml extract had a significant effect on the diameter of fibers and the average fber diameter with Artemisia extract (218.4 nm) compared to the fibers without extract (204.8 nm) were higher. The tensile stress at the tear point of the nanofibers with Artemisia extract (3.04 MPa) was lower than the fibers without the extract (3.46 MPa) and elongation at break was higher (7.6%).The nanofibers with the extract had more resistance temperature than non-extract fibers. This is due to the crystal state of Artemisia extract in the fibers. The nanofibers produced with Artemisia extract had inhibitory properties for both studied bacteria. Nanofibers with 100 mg/ml extract completely controlled the bacterial growth. Nanofibers with 20 and 50 mg/ml of extract had a better inhibitory effect on Pseudomonas aeruginosa than Staphylococcus aureus. The Addition of Artemisia extract improved the antimicrobial properties of chitosan nanofibers.