Potent antibacterial nanocomposites from okra mucilage/chitosan/silver nanoparticles for multidrug-resistant Salmonella Typhimurium eradication

Abstract

The polymeric nanocomposites (NCs), constructed from okra (Abelmoschus esculentus) fruits mucilage (OM), silver nanoparticles (AgNPs), and chitosan (Ch), were fabricated as potential candidates to overcome drug-resistant Salmonella Typhimurium bacteria. AgNPs were directly mediated by OM, with 4.2 nm mean diameters. The composed NCs from Ch/OM/AgNPs were innovatively synthesized and the various ratios of Ch:OM/AgNPs affected the NCs particles’ size and charges. The infrared analysis of employed materials/NCs validated their interactions and conjugations. The antibacterial assays of NCs against different resistant S. Typhimurium strains indicated the efficiency of polymeric NCs to inhibit bacteria with significant superiority over standard antibiotics. The NCs that contained equal ratios from Ch and OM/AgNPs were the best formulation (mean diameter, 47.19 nm and surface charge, +16.9 mV) to exhibit the strongest actions toward S. Typhimurium. The NCs caused severe deformation, destruction, and lysis in exposed bacteria, as traced with scanning microscopy. The biosynthesis of AgNPs using OM and their nanoconjugation with Ch provided effectual natural biopolymers NCs with enhanced expected biosafety and efficiency against drug-resistant S. Typhimurium strains, which supports their potential applications as disinfectant, sterilizing, and curative antibacterial agents.

Keywords

• antimicrobial
• bactericidal
• biopolymers
• biosynthesis
• nanoconjugation