Myco-Synthesized Zinc Oxide Nanoparticles as a Sustainable Tool for Controlling Aspergillus Species and Mycotoxin Production in Agriculture

Abstract

One promising eco-friendly, cost-effective and safe alternative is the use of biogenic nanoparticles (NPs), particularly zinc oxide nanoparticles synthesized by fungi (Myco-synthesized ZnO-NPs). ZnO nanoparticles have demonstrated antifungal properties, making them a potential tool for controlling fungal growth and mycotoxin production. The 'One Health' approach emphasizes the interconnection between human, animal, and environmental health, which is crucial for managing diseases affecting agriculture and public health.This approach is particularly relevant in the agro-industrial sector, which faces the challenge of feeding a growing global population projected to reach around 10.3 billion people in the mid-2080s. The sector must balance increasing food production with ensuring food safety and quality. Additionally, climate change is expected to impact the development of pathogens, changing the susceptibility of hosts and creating new conditions for diseases. Fungal diseases are a major threat to many crops. In Argentina, corn (Zea mays L.) is a major crop, as the country is the fifth-largest producer and fourth-largest exporter globally.However, fungal contamination can lead to the production of mycotoxins which contaminate crops under several environmental conditions. Among the Aspergillus species, A. flavus is particularly problematic, producing aflatoxins (AFs), which are highly toxic, carcinogenic and genotoxic. These toxins pose significant health risks to both animals and humans, especially in the context of food consumption. This review provides an overview of conventional chemical and physical methods for synthesizing ZnO-NPs. Special emphasis is placed on recent advances in using fungal strains, particularly filamentous fungi, for their myco-synthesis. It also discusses the conditions influencing their production, their demonstrated antifungal efficacy and explores their potential application in controlling toxigenic fungi and their associated mycotoxins. While numerous studies have successfully achieved the myco-synthesis of ZnO-NPs and confirmed their antifungal properties, primarily in vitro, no research has yet investigated their potential to reduce mycotoxin production in crops. Further studies are also required to evaluate the environmental impact of myco-synthesized ZnO-NPs through toxicological assessments to confirm their low or negligible toxicity.