Synthesis and characterization of chitosan–copper nanocomposites and their fungicidal activity against two sclerotia-forming plant pathogenic fungi

Abstract

In this report, the metal-vapor synthesis (MVS) was used for the preparation of copper nanoparticles which was then used for the preparation of chitosan-copper nanocomposite. The antifungal activity of Cu@Chit NCs against two sclerotium-forming plant pathogenic fungi Sclerotium rolfsii (S. rolfsii) and Rhizoctonia solani (R. solani) AG-4 was evaluated in vitro and their effects on hyphal morphology, and sclerotia formation were observed for the first time. The NCs were prepared through impregnation of chitosan with colloid solution of copper nanoparticles in organic solvent (acetone or toluene). Transmission electron microscopy shows that the particles have predominantly spherical form, polydisperse character, the mean diameter about 2-3 nm and a rather uniform distribution in the chitosan matrice. Analysis of the small angle scattering curves suggests that the copper particles in the NCs with the size of B2 nm are mostly located in the chitosan pores with the same size. The effect of Cu@Chit NCs on fungal growth reveals some significant inhibitory activity against two tested fungi. The highest level of inhibition against S. rolfsii and R. solani AG-4 was observed using the high concentrations of Cu@Chit NC prepared using acetone as a solvent. A loss of the cytoplasm content, cytoplasmic coagulation, irregular shape of mycelia, or destruction in the hyphae was confirmed. The experiments demonstrate that the Cu@Chit NC synthesized via MVS using acetone was more effective than that of toluene in inhibiting fungal hyphae growth against R. solani AG-4 and S. rolfsii. The results show that the Cu@Chit NCs are fungicidal against both the tested fungus at high concentrations and the fungicidal or fungistatic activity is dependent on the tested fungus species.

Copper-Chitosan Nanocomposite Hydrogels Against Aflatoxigenic Aspergillus flavus from Dairy Cattle Feed

“…XRF analysis shows that the metal proportion of the Cu-carrying powders based on ChitLMW and ChitHMW is 0.5 and 0.83%, respectively. Previously, the same method for preparing Cu-carrying chitosan powders with a high copper concentration of 3–5% w / w was used [ 20 ].…”

“…It was previously demonstrated that the surface of the composite prepared with Cu-acetone organosol contains two oxidized copper states Cu 2+ and Cu + , with concentrations (at. %) of 10.7 and 3.6%, respectively [ 20 ]. Experimental SAXS curves of Cu-carrying chitosan and pristine non-modified chitosan (ChitLMW) are described in Figure 4 A.…”

“…Chitosan powder decorated with Cu NPs was prepared according to the procedure described in the previously published works [ 17 , 18 , 19 , 20 ]. For the preparation of organosol, 0.56 g of Cu foil (about 200 µm of thickness) was resistively dispersed from the tantalum boat (90 mm × 5 mm) and co-condensed with 160 mL of acetone on the liquid nitrogen-cooled walls of a quartz 5 L vessel.…”

Hybrid magnetic materials based on polyethylene containing co and ni nanoparticles

“…A typical MVS reactor [1][2][3][4] has an evacuated volume of 5 l. Nickel or cobalt samples (0.3-0.5 g) are evaporated into vacuum of 10 -2 Ра with a W evaporator.…”

Preparation and characterization of biomedical collagen–chitosan scaffolds with entrapped ibuprofen and silver nanoparticles

“…A significant advantage of the method is absence of restrictions regarding the choice of metal. By means of MVS, various types of natural polymers, such as chitosan , hyaluronic acid , and cellulose , were incorporated with metal nanoparticles. It has been demonstrated that MVS can be employed for successful preparation of gauze bandage loaded with AgNPs with pronounced antibacterial activity against S. aureus , Staphylococcus haemolyticus , P. aeruginosa , Klebsiella pneumoniae , Escherichia coli , and Moraxella spp .…”