Antibacterial activity of chitosan nanoparticles 4% from blue swimming crab shell waste (<i>Portunus pelagicus</i>) against <i>Staphylococcus aureus</i>

Abstract In this study, chitosan nanoparticles were prepared from waste chitosan of blue swimming crab shell ( Portunus pelagicus ) using ionic gelation method which has the ability to be biodegradable, biocompatible, antimicrobial and non-toxic. The chitosan nanoparticles were characterized by FT-IR spectrophotometry with the deacetylation degree of 84.98%. Chitosan nanoparticles were tested for the purpose of antibacterial action against Staphylococcus aureus , which is one of the bacteria that cause gangrene infections in patients with diabetes mellitus. The purpose of this research is to examine the antimicrobial activity of chitosan nanoparticles obtained from blue swimming crab shell waste ( Portunus pelagicus ) against Staphylococcus aureus . The method used was antibacterial activity testing with the well diffusion method at concentrations of 4%. The observation results of the antibacterial activity test of chitosan nanoparticles against Staphylococcus aureus bacteria were categorized as strong at concentration of 4% with an inhibition zone starting at 10.93 mm. At 4% concentration, the most significant zone of inhibition reached 27.45 mm. At high concentrations, the development of bacteria of Staphylococcus aureus was significantly impeded by blue swimming crab shell particles ( Portunus pelagicus ) chitosan nanoparticles, with an inhibition diameter of higher than 20 mm.