Omar Hamed

Abstract

Food waste is one of the major problems of today's world and thus there is a need to utilize it in innovative applications to reduce the problems associated with it. One of those is the utilization of banana peels in the green synthesis of nanoparticles where the extract of such peels was found to contain polyphenolic compounds that would serve as capping agents for the growing nanoparticles. Our aim in this study was to investigate the use of banana peel extract (BPE) in the synthesis of zinc oxide nanoparticles (ZnO NPs) and to compare the prepared NPs with commercial bulk ZnO particles and also with ZnO NPs prepared using nonionic and anionic surfactants. All samples were characterized by using different characterization techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), zeta sizer and UV-vis spectrophotometry. The antioxidant and antibacterial activities of the ZnO NPs were also investigated to select the NPs that could be incorporated in a biodegradable food packaging film. The ZnO NPs synthesized using the BPE were found superior to all NPs prepared in this study in most of the characterization steps. These NPs were found to have the smallest particle size (6 nm), as well as attaining this size for several days in aqueous solutions without significant size fluctuation. In addition, a more uniform spherical morphology was observed for these NPs, unlike the non-uniform flake like structures of the remaining NPs. Moreover, the capping of the BB extract components on these NPs rendered them antioxidant with a DPPH scavenging activity of 76.91%, even though ZnO NPs are known to produce reactive oxygen species (ROS). With regards to the antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), all ZnO NPs were found to be potent antimicrobial agents with minor differences amongst them against E. coli and slight differences against S. aureus. ZnO NPs were then incorporated in a biopolymer (starch) for the synthesis of biodegradable films aimed for antimicrobial food packaging. The starch/ZnO NPs film composites were compared with commercial nylon/evoh film with regards to antioxidant and antimicrobial activity. It was found that the films with ZnO NPs derived from BPE exhibited DPPH scavenging activity of 20.9%, which was 50% higher than that of the commercial film. In addition, the films with ZnO NPs exhibited antibacterial properties towards S. aureus and E. coli when tested using disk diffusion method unlike the commercial nylon/evoh film which did not exhibit any antibacterial activities.

Department

Chemistry Department

Degree Name

MS in Chemistry

Graduation Date

2-1-2018

Submission Date

January 2018

First Advisor

Mamdouh, Wael

Committee Member 1

El-Meshad, Aliaa

Committee Member 2

Tallima, Hatem

Extent

174 p.

Document Type

Master's Thesis

Rights

The author retains all rights with regard to copyright. The author certifies that written permission from the owner(s) of third-party copyrighted matter included in the thesis, dissertation, paper, or record of study has been obtained. The author further certifies that IRB approval has been obtained for this thesis, or that IRB approval is not necessary for this thesis. Insofar as this thesis, dissertation, paper, or record of study is an educational record as defined in the Family Educational Rights and Privacy Act (FERPA) (20 USC 1232g), the author has granted consent to disclosure of it to anyone who requests a copy.

Institutional Review Board (IRB) Approval

Not necessary for this item

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