title: Chitosan nanocomposite films based on Ag-NP and Au-NP biosynthesis by Bacillus Subtilis as packaging materials.
abstract: Chitosan-silver (CS-Ag) and Chitosan-gold (CS-Au) nanocomposites films were synthesized by a simple chemical method. A local bacterial isolate identified as Bacillus subtilis ss subtilis was found to be capable to synthesize both silver nanoparticles (Ag-NP) and gold nanoparticles (Au-NP) from silver nitrate (AgNO3) and chloroauric acid (AuCl(4-)) solutions, respectively. The biosynthesis of both Ag-NP and Au-NP characterize using UV/vis spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD), and then added to chitosan by different ratios (0.5, 1 and 2%). The prepared chitosan nanocomposites films were characterize using UV, XRD, SEM and TEM. Moreover, the antibacterial activity of the prepared films was evaluated against gram positive (Staphylococcus aureus) and gram negative bacteria (Pseudomonas aerugenosa), fungi (Aspergillus niger) and yeast (Candida albicans). Therefore, these materials can be potential used as antimicrobial agents in packaging applications.
authors.affiliation: Packing and Packaging Materials Department, National Research Center, Dokki, Cairo, Egypt. Electronic address: amyoussef27@yahoo.com.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Youssef
authors.affiliation: Microbial Chemistry Department, Genetic engineering and Biotechnology Division, National Research Center, Behooth St., Giza, Egypt.
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Abdel-Aziz
authors.affiliation: Dairy Department, National Research Center, Dokki, Cairo, Egypt.
authors.forename: Samah M
authors.initials: SM
authors.lastname: El-Sayed
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology; D001234:Aspergillus niger / Q000187:drug effects; D001412:Bacillus subtilis / Q000187:drug effects / Q000378:metabolism*; D048271:Chitosan / Q000737:chemistry*; D006046:Gold / Q000737:chemistry* / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D019064:Product Packaging; D012441:Saccharomyces cerevisiae / Q000187:drug effects; D012834:Silver / Q000737:chemistry* / Q000378:metabolism; D013499:Surface Properties
chemical_list: D000890:Anti-Infective Agents; D012834:Silver; D006046:Gold; D048271:Chitosan
keywords: Biosynthesis; Chitosan; Nanocomposites antibacterial; Nanoparticles; Packaging