Acid protease functionalized novel silver nanoparticles (APTs-AgNPs): A new approach towards photocatalytic and biological applications

Int J Biol Macromol. 2023 Jul 1;242(Pt 2):124809. doi: 10.1016/j.ijbiomac.2023.124809. Epub 2023 May 11.

Abstract

Herein, we described for the first time, an efficient biogenic synthesis of APTs-AgNPs using acid protease from Melilotus indicus leaf extract. The acid protease (APTs) has an essential role in the stabilization, reduction, and capping of APTs-AgNPs. The crystalline nature, size, and surface morphology of APTs-AgNPs were examined using different techniques such as XRD, UV, FTIR, SEM, EDS, HRTEM, and DLS analysis. The generated APTs-AgNPs demonstrated notable performance as dual functionality (photocatalyst and antibacterial disinfection). By destroying 91 % of methylene blue (MB) in <90 min of exposure, APTs-AgNPs demonstrated remarkable photocatalytic activity. APTs-AgNPs also showed remarkable stability as a photocatalyst after five test cycles. Furthermore, the APTs-AgNPs was found to be a potent antibacterial agent with inhibition zones of 30(±0.5 mm), 27(±0.4 mm), 16(±0.1 mm), and 19(±0.7 mm) against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, respectively, under both light and dark conditions. Furthermore, APTs-AgNPs effectively scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, demonstrating their potent antioxidant activity. The outcomes of this study thus demonstrates the dual functionality of APTs-AgNPs produced using the biogenic approach method as a photocatalyst and an antibacterial agent for effective microbial and environmental control.

Keywords: Acid protease; AgNPs; Antibacterial activity; DPPH activity; Photocatalytic activity.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology
  • Endopeptidases / pharmacology
  • Escherichia coli
  • Metal Nanoparticles* / chemistry
  • Microbial Sensitivity Tests
  • Peptide Hydrolases* / pharmacology
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Silver / chemistry
  • Silver / pharmacology

Substances

  • Peptide Hydrolases
  • Silver
  • Plant Extracts
  • Anti-Bacterial Agents
  • Endopeptidases