New formula of the green synthesised Au@Ag core@shell nanoparticles using propolis extract presented high antibacterial and anticancer activity

Abstract

Antimicrobial alternatives such as nanoparticles are critically required to tackle bacterial infections, especially with the emerging threat of antibiotic resistance. Therefore, this study aimed to biosynthesize Au–Ag nanoparticles using propolis as a natural reducing agent and investigate their antibacterial activity against antibiotic-resistant Staphylococcus sciuri (S. sciuri), Pseudomonas aeruginosa (P. aeruginosa), and Salmonella enterica Typhimurium (S. enterica), besides demonstrating their anticancer activity in cancer cell lines. The biosynthesized Au@AgNPs were characterized using UV–Vis spectrophotometer, Transmission Electron Microscopy (TEM), Zeta potential, Dynamic Light Scattering (DLS), Fourier Transformation Infrared (FTIR), and Scanning Electron Microscopy (SEM). Moreover, the detection of antibacterial activity was assessed through disc diffusion, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC), time-killing curve, and detection of cell membrane integrity via SEM. As a result, the UV–Vis spectrum revealed the formation of Au@AgNPs in a single peak between 533 and 555 nm. Furthermore, FTIR analysis confirmed nanoparticles’ green synthesis due to the presence of carbon functional groups. The formulated Au@AgNPs showed antibacterial activity against both Gram-positive and Gram-negative bacteria. The MIC and the MBC of P. aeruginosa and S. sciuri were 31.25 µg/mL. However, nanoparticles were more effective on S. enterica with MIC of 7.5 µg/mL and MBC of 15.6 µg/mL. Furthermore, the time-killing curve of the three model bacteria with the treatment was effective at 50 µg/mL. Besides, SEM of the tested bacteria indicated unintegrated bacterial cell membranes and damage caused by Au@AgNPs. Regarding the anticancer activity, the results indicated that the biosynthesized Au@AgNPs have a cytotoxic effect on HEPG2 cell lines. In conclusion, this research revealed that the green synthesized Au@AgNPs could be effective antibacterial agents against S. sciuri, P. aeruginosa, and S. enterica and anticancer agents against HEPG2.

Characterization and comprehensive genome analysis of novel bacteriophage, vB_Kpn_ZCKp20p, with lytic and anti-biofilm potential against clinical multidrug-resistant Klebsiella pneumoniae

“…Next, the wells’ absorbance was measured at 570 nm in a FLUOstar Omega Microplate Reader. The OD values were used to calculate the viability of the phage-treated cells as percentage of the untreated cells (negative control) by the following formula ( Carmichael et al., 1987 ; van Meerloo et al., 2011 ; Rahimzadeh Torabi et al., 2021 ; Rezk et al., 2022 ). The cell viability assay was conducted in four technical replicates and three biological replicates for each incubation time point.…”

Breaking Barriers in Eco-Friendly Synthesis of Plant-Mediated Metal/Metal Oxide/Bimetallic Nanoparticles: Antibacterial, Anticancer, Mechanism Elucidation, and Versatile Utilizations

“…In several other fields such as in food industries and construction units, MNPs are used extensively. They have been examined for a variety of clinical uses, including imaging contrast agents, tumor-targeting genes, and drug carriers [374,375].…”

In Situ Green Synthesis of Co3O4@ZnO Core-Shell Nanoparticles Using Datura stramonium Leaf Extract: Antibacterial and Antioxidant Studies

“…In Co 3 O 4 @ZnO core-shell NPs, the core material Co 3 O 4 was coated by ZnO which acts as a shell to control its reactivity and enhance thermal stability. Additionally, the shell decreases the toxicity of Co 3 O 4 NPs and increases the dispersibility [35][36][37].…”