A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Innovation, Nutrition and Health, School of Environment, Resources and Development

Thesis (M. Sc.) - Asian Institute of Technology, 2023

This study focuses on the fabrication of self-assembled bioactive peptides to nanoparticles using peptides and proteins obtained from Peas (Pisum sativum) and Rice (Oryza sativa) to enhance their functionality. The goal of the research is to create a new method for using these plant-based materials in applications to combat multidrug and antibiotic-resistant drugs used in the food system. Antibiotic-resistant bacteria are immune to the effects of commonly used antibiotics, making it difficult to treat infections caused by these bacteria. The study investigates the potential of these peptide and nanoparticles in terms of their physical and chemical properties, as well as their ability to improve the functionality of the proteins and peptides they are made from, and conducting analysis and characterization of the antimicrobial and antioxidant activity of the bio-nanoparticles formed. The study found that the nanoparticles denoted as PPN2 were effective in inhibiting the growth of S.aureus and E.coli, with a zone of inhibition of initially at 11 ± 0.2 to 16.4 ± 0.1, MIC of 75mg/ml, a particle size of d = ~330 nm and zeta potential of -26.23 ± 0.88, obtained under optimal conditions. Bioactive properties were confirmed by conduction agar well and disc diffusion method, broth macrodilution, antibiogram of microbes used, and DPPH assay. Investigation of the properties and potential applications of plant-based nanoparticles (PPN) derived from Pea (Pisum sativum) peptides (PP) and Rice (Oryza sativa) peptides (RP). The research focuses on six different nanoparticles: PPN1, PPN2, PPN3, RPN1, RPN2, and RPN3, which were fabricated using different heat treatments at 45oC, 65oC, and 85oC, respectively. The physical study of fabricating peptide nanoparticles was further confirmed for their morphological study conducted by SDS-PAGE and scanning electron microscope (SEM) and with SDS-PAGE. The chemical study was confirmed for the effects of thermal treatment to the nanoparticles presented by Fourier transform infrared spectroscopy (FTIR). The study also explores the issue of natural peptides that lack efficient antimicrobial peptides in commercial applications and often present with instability with drawback benefits. Thus, the potential of these fabricated nanoparticles in applications for disinfectants provides insight into the potential uses of plant-based nanoparticles in a wide range of fields.