Antimicrobial Activity of Silver and Gold Nanoparticles Prepared by Photoreduction Process with Leaves and Fruit Extracts of Plinia cauliflora and Punica granatum

• Published in: Molecules (Basel, Switzerland) Switzerland), 2022-10, Vol.27 (20), p.6860
• Main Authors: Franzolin, Marcia Regina, Courrol, Daniella dos Santos, Silva, Flavia Rodrigues de Oliveira, Courrol, Lilia Coronato
• Format: Article
• Language: English
• Subjects: antibacterial activity; Antibiotics; Antiinfectives and antibacterials; Antimicrobial activity; Antimicrobial agents; Bacteria; Clinical isolates; Deoxyribonucleic acid; DNA; Drug resistance; E coli; Enzymes; Fruits; Gold; gold nanoparticles; Gram-negative bacteria; Gram-positive bacteria; Klebsiella; Leaves; Methicillin; Microorganisms; Multidrug resistant organisms; Nanoparticles; Nosocomial infections; Oxidative stress; Penicillin; Photoreduction; Phytochemicals; Plinia cauliflora; Pseudomonas aeruginosa; Punica granatum; Signal transduction; Silver; silver nanoparticles; Stabilizers (agents); Staphylococcus aureus; Staphylococcus infections; Transmission electron microscopy; Trees; Yeasts; Zeta potential
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules27206860

The increased number of resistant microbes generates a search for new antibiotic methods. Metallic nanoparticles have emerged as a new platform against several microorganisms. The nanoparticles can damage the bacteria membrane and DNA by oxidative stress. The photoreduction process is a clean and low-cost method for obtaining silver and gold nanoparticles. This work describes two original insights: (1) the use of extracts of leaves and fruits from a Brazilian plant Plinia cauliflora, compared with a well know plant Punica granatum, and (2) the use of phytochemicals as stabilizing agents in the photoreduction process. The prepared nanoparticles were characterized by UV-vis, FTIR, transmission electron microscopy, and Zeta potential. The antimicrobial activity of nanoparticles was obtained with Gram-negative and Gram-positive bacteria, particularly the pathogens Staphylococcus aureus ATCC 25923; Bacillus subtilis ATCC 6633; clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Enterococcus faecalis; Escherichia coli ATCC 25922; Escherichia coli O44:H18 EAEC042 (clinical isolate); Klebsiella pneumoniae ATCC 700603, Salmonella Thiphymurium ATCC 10231; Pseudomonas aeruginosa ATCC 27853; and Candida albicans ATCC 10231. Excellent synthesis results were obtained. The AgNPs exhibited antimicrobial activities against Gram-negative and Gram-positive bacteria and yeast (80–100%), better than AuNPs (0–87.92%), and may have the potential to be used as antimicrobial agents.