Sustainably produced cashew gum-capped zinc oxide nanoparticles show antifungal activity against Candida parapsilosis

The peculiar properties derived from the reduction in materials sizes from macro to nanoscale has made the use of nanomaterials increasingly popular in pharmaceutical and health industry. Often, the synthesis of these nanomaterials is achieved with the aid of harmful chemical reagents, which could increase their toxicity towards the environment and users. In this study, Zinc oxide nanoparticles (ZnONPs) were synthesized by a simple method, using the natural polysaccharides Cashew Gum (CG) and Carboxymethylated Cashew Gum (CMCG) as stabilizing templates. The nanoparticles were characterized by UV–vis spectroscopy, FTIR, XRD and AFM. These methods confirmed the formation of nanoparticles with sizes between 35 nm and 129 nm, depending on the type and concentration of polysaccharide used. In addition, the ZnONPs presented significant inhibition towards yeasts of the genus Candida, particularly Candida parapsilosis - an important emerging pathogen, with no toxicity against red blood cells, which indicates a promising material that could be safely used in medical devices or in pharmaceutical formulations, as a support to antifungal treatments. [Display omitted] •ZnONPs were sustainably produced using cashew gum and carboxymethylated cashew gum.•The ZnONPs showed activity against Candida parapsilosis at low concentrations.•All reagents used were biocompatible, suggesting the potential low toxicity.•No toxicity of the ZnONPs was observed against erythrocytes.