Detection and Quantification of Nanoparticle-Induced Intracellular ROS in Live Cells by Laser Scanning Confocal Microscopy

The generation and transformation mechanisms of reactive oxygen species in the environment and their implications for pollution control processes: A review

Reactive oxygen species (ROS), substances with strong activity generated by oxygen during electron transfer, play a significant role in the decomposition of organic matter in various environmental settings, including soil, water and atmosphere. Although ROS has a short lifespan (ranging from a few nanoseconds to a few days), it continuously generated during the interaction between microorganisms and their environment, especially in environments characterized by strong ultraviolet radiation, fluctuating oxygen concentration or redox conditions, and the abundance of metal minerals. A comprehensive understanding of the fate of ROS in nature can provide new ideas for pollutant degradation and is of great significance for the development of green degradation technologies for organic pollutants. At present, the review of ROS generally revolves around various advanced oxidation processes, but lacks a description and summary of the fate of ROS in nature, this article starts with the definition of reactive oxidants species and reviews the production, migration, and transformation mechanisms of ROS in soil, water and atmospheric environments, focusing on recent developments. In addition, the stimulating effects of ROS on organisms were reviewed. Conclusively, the article summarizes the classic processes, possible improvements, and future directions for ROS-mediated degradation of pollutants. This review offers suggestions for future research directions in this field and provides the possible ROS technology application in pollutants treatment.

Does functionalised nanoplastics modulate the cellular and physiological responses of aquatic fungi to metals?

Co-contamination of freshwaters by nanoplastics (NPs; ≤ 1 μm) and metals is an emerging concern. Aquatic hyphomycetes play a crucial role as primary decomposers in these ecosystems. However, concurrent impacts of NPs and metals on the cellular and physiological activities of these fungi remain poorly understood. Here, the effects of environmentally realistic concentrations of two types of polystyrene (PS) NPs (bare and -COOH; up to 25 μg L-1) and copper (Cu; up to 50 μg L-1) individually and all possible combinations (NPs types and Cu) on Articulospora tetracladia, a prevalent aquatic hyphomycete, were investigated. Endpoints measured were intracellular reactive oxygen species accumulation, plasma membrane disruption and fungal growth. The results suggest that functionalised (-COOH) NPs enhance Cu adsorption, as revealed by spectroscopic analyses. Notably, NPs, Cu and their co-exposure to A. tetracladia can lead to ROS accumulation and plasma membrane disruption. In most cases, exposure to treatments containing -COOH NPs with Cu showed greater cellular response and suppressed fungal growth. By contrast, exposure to Cu individually showed stimulatory effects on fungal growth. Overall, this study provides novel insight that functionalisation of NPs facilitates metal adsorption, thus modulating the impacts of metals on aquatic fungi.