Phyto-Functionalized Silver Nanoparticles Derived from Conifer Bark Extracts and Evaluation of Their Antimicrobial and Cytogenotoxic Effects

Abstract

Silver nanoparticles synthesized using plant extracts as reducing and capping agents showed various biological activities. In the present study, colloidal silver nanoparticle solutions were produced from the aqueous extracts of Picea abies and Pinus nigra bark. The phenolic profile of bark extracts was analyzed by liquid chromatography coupled to mass spectrometry. The synthesis of silver nanoparticles was monitored using UV-Vis spectroscopy by measuring the Surface Plasmon Resonance band. Silver nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, energy dispersive X-ray and transmission electron microscopy analyses. The antimicrobial and cytogenotoxic effects of silver nanoparticles were evaluated by disk diffusion and Allium cepa assays, respectively. Picea abies and Pinus nigra bark extract derived silver nanoparticles were spherical (mean hydrodynamic diameters of 78.48 and 77.66 nm, respectively) and well dispersed, having a narrow particle size distribution (polydispersity index values of 0.334 and 0.224, respectively) and good stability (zeta potential values of −10.8 and −14.6 mV, respectively). Silver nanoparticles showed stronger antibacterial, antifungal, and antimitotic effects than the bark extracts used for their synthesis. Silver nanoparticles obtained in the present study are promising candidates for the development of novel formulations with various therapeutic applications.

Green Synthesis and Characterization of Silver Nanoparticles Using a Lythrum salicaria Extract and In Vitro Exploration of Their Biological Activities

“…The FTIR spectrum of the extract shows a broad absorption peak at 3452 cm −1 , which was related to the stretching vibration of -OH groups found in alcohols and phenols and to the N-H stretching from amides. The peaks at 2924 cm −1 and 2854 cm −1 corresponded to C-H stretching and bending vibrations of CH 3 and CH 2 (alkanes) [ 19 , 28 ]. The bands detected at 1736 cm −1 and 1624 cm −1 were connected to the vibration of C=O from amides and carboxylic groups, and -C=C- aromatic rings, respectively [ 38 ].…”

“…The theoretical concentration of AgNPs in the colloidal synthesis mixture was calculated using a mathematical method [ 18 , 19 ]. Firstly, the average number of atoms per nanoparticle (N) was determined through Equation (1): where π = 3.14, ρ = 10.5 g/cm 3 (density of face centered cubic silver), D = 133.5 × 10 −7 cm (average diameter of nanoparticles), M = 107.868 g/mol (atomic mass of silver) and N A = 6.023 × 10 23 mol −1 (Avogadro’s number).…”

“…Secondly, the molar concentration of nanoparticles in the resulting colloidal mixture ( C ) could be calculated only by considering that all silver ions (Ag + ) were entirely converted to AgNPs in the biosynthesis process. Equation (2) was applied for the determination of C : where N T = total amount of Ag atoms added as AgNO 3 (3.0 mM = 0.003 M), N = average number of atoms per nanoparticle, V = reaction volume (0.22 L) and N A = Avogadro’s number [ 18 , 19 ].…”

Electrospun Copoly(ether imide) Nanofibers Doped with Silver-Loaded Zeolite as Materials for Biomedical Applications

“…The absence of antimicrobial activity in electrospun membrane co-PEI-1 containing only zeolite L NPs in its structure indicates that zeolite itself does not possess antimicrobial activity, 56 but its properties (negatively charged structure) allow loading with metal ions such as Ag + , which is known for its antimicrobial potential, 57 aspects that were confirmed when testing electrospun membranes co-PEI-2 and co-PEI-3.…”

Synergistic and antibiofilm potential of Curcuma aromatica derived silver nanoparticles in combination with antibiotics against multidrug-resistant pathogens

“…The factors influencing the biological activity of NPs include size distribution, morphology, surface charge, surface chemistry and capping agents ( Cheon et al, 2019 ; Fahimirad et al, 2019 ). AgNPs synthesized using extracts of Foeniculum vulgare ( Talank et al, 2022 ), Picea abies and Pinus nigra ( Macovei et al, 2022 ), Zataria multiflora ( Barabadi et al, 2021 ), Punica granatum ( Swilam and Nematallah, 2020 ), Lysiloma acapulcensis ( Garibo et al, 2020 ), Gardenia resinifera ( Parit et al, 2020 ), Brassica oleracea ( Ansar et al, 2020 ), Piper betle ( Shah et al, 2019 ), Prosopis juliflora ( Arya et al, 2019 ), Rumex hastatus ( Rashid et al, 2019 ), Galega officinalis ( Manosalva et al, 2019 ) and Terminalia mantaly ( Majoumouo et al, 2019 ) have been known to exhibit enhanced antimicrobial activity against P. aeruginosa and S. aureus . Biofilm inhibition by AgNPs synthesized using extracts of Zataria multiflora ( Barabadi et al, 2021 ), Piper betle ( Shah et al, 2019 ) Rhodiola rosea ( Singh et al, 2018a ), and Cannabis sativa ( Singh et al, 2018b ) have been reported in P. aeruginosa and S. aureus .…”