Synthesis of phytochemicals-stabilized gold nanoparticles and their biological activities against bacteria and Leishmania

Microb Pathog. 2017 Sep:110:304-312. doi: 10.1016/j.micpath.2017.07.009. Epub 2017 Jul 11.

Abstract

Nanoscale materials have shown promising results in the field of medicine as therapeutic agents and drugs delivery vehicles. In the current study, gold nanoparticles (AuNPs) were prepared by a green and facile method using the aqueous extract of Rhazya stricta decne as a source of reducing and stabilizing agents. The bio-fabricated AuNPs were characterized by UV-visible spectroscopy, X-ray diffraction (XRD), Transmission electron microscopy (TEM) and FTIR spectroscopy. Antimicrobial activities of the biosynthesized AuNPs were tested against Leishmania tropica (HTD7), E. coli and S. aureus. AuNPs were the most effective agents in inhibiting the growth of intra-THP-1 amastigotes at 100 μg/mL concentration (IC50 = 43 μg/mL) after 48-h incubation. In addition, the prepared AuNPs also displayed good activity against E. coli (MIC = 25.0 μg/mL) and Bacillus subtilis (50.0 μg/mL). Interestingly, biogenic AuNPs did not exhibit cytotoxic effect against the THP-1 cells after 24 h exposure. The findings of this study conclude that phytochemicals-stabilized AuNPs could be a safe and effective source of antimicrobial agents.

Keywords: Gold nanoparticles; Leishmania tropica HTD(7); Rhazya stricta decne; THP-1 cells.

MeSH terms

  • Anti-Infective Agents / chemical synthesis*
  • Anti-Infective Agents / pharmacology*
  • Apocynaceae / chemistry
  • Bacillus subtilis / drug effects
  • Bacteria / drug effects*
  • Escherichia coli / drug effects
  • Gold / chemistry*
  • Gold / pharmacology
  • Green Chemistry Technology
  • Humans
  • Leishmania / drug effects*
  • Leishmania tropica / drug effects
  • Metal Nanoparticles / chemistry*
  • Metal Nanoparticles / ultrastructure
  • Microscopy, Electron, Transmission
  • Particle Size
  • Phytochemicals / chemical synthesis*
  • Phytochemicals / pharmacology*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology
  • Reactive Oxygen Species / analysis
  • Spectrophotometry, Ultraviolet
  • Spectroscopy, Fourier Transform Infrared
  • Staphylococcus aureus / drug effects
  • THP-1 Cells / drug effects
  • X-Ray Diffraction

Substances

  • Anti-Infective Agents
  • Phytochemicals
  • Plant Extracts
  • Reactive Oxygen Species
  • Gold