The catalytic reduction of nitro compounds is currently a hot research area, how to efficiently and stably degrade such toxic and harmful substances has become the research goal of many researchers. In this work, an Artemia cyst shell (ACS)–TiO2–MoS2 ternary porous structure was proposed and prepared as a catalyst for the reduction of 2-nitroaniline (2-NA) and 4-nitrophenol (4-NP). The ACS has a large number of porous structures, exhibits a good binding ability with TiO2 and MoS2, and provides a large number of active sites for the catalytic reduction process. The obtained composite material has a good reduction effect on 4-NP and 2-NA, with a good stability and recyclability, which is obviously higher than the reduction effect of ACS–TiO2 and MoS2 under the same conditions. This work provides ideas for the design of porous catalytic materials.
Yanlin Wei,Wei Liu,Fengling Zhang,Yang Chen,Dongxin Wei,Hangyu Lin,Tao He
Inorganic mercury (Hg) and methylmercury (MeHg) have emerged as global pollutants owing to their long-term environmental stability and bioaccumulation. These heavy metals enter aquatic systems via industrial emissions, coal combustion, and natural processes, posing a serious threat to ecosystems and human health. This study assesses the impact of Hg2+ and MeHg on the growth and development of brine shrimp (Artemia franciscana) nauplii by analyzing the histopathological effects on their tissues. Brine shrimp nauplii from the Bohai Bay in China were selected as the study subjects and exposed to 1 μmol/L solutions of HgCl₂ and MeHgCl. Tissue sections were continuously taken at different immersion times. After staining with the standard hematoxylin-eosin (HE) method, the tissue morphology of brine shrimp nauplii under different forms of Hg stress was observed under a light microscope. The results showed that MeHg exhibited significantly greater toxicity to brine shrimp nauplii than Hg2+. Under the same exposure time, the MeHg group exhibited more pronounced epithelial cell damage, nuclear material disorder, and nucleoplasm diffusion outside the nucleus than the HgCl₂ group. This finding provides an important theoretical support for further research into the toxicological mechanisms of MeHg and Hg2+, and highlights that the toxic effects of methylmercury on aquatic organisms.
Hangyu Lin,Yanlin Wei,Junjie Huang,Qun Lu,Song Zhu,Jianguang Qin,Shengqi Su,Tao He
Mercury poses significant hazards to aquatic organisms, causing neurotoxicity, and metabolic disorders. Research on the dynamic distribution of mercury within zooplankton is limited, and the metabolic mechanisms of mercury in zooplankton remain unclear. In this study, we employed a mercury-specific fluorescent probe (aggregation-induced emission luminogen, AIEgen) to visualize the in vivo distribution of Hg 2 + and MeHg in brine shrimp. Both Hg 2+ and MeHg accumulated predominantly in the head, ocellus, midgut, and midgut–hindgut transition, with Hg 2+ further affecting the hindgut and anal opening. Transcriptomics and metabolomics analyses revealed that Hg 2+ exposure in the midgut likely induced the efflux activity of ABC transporters. The linoleic acid metabolism, α-linolenic acid metabolism, tryptophan metabolism, and retinol metabolism pathways were potentially associated with MeHg accumulation in the head and ocellus. Additionally, the cytochrome P450 pathway participated in detoxification. Enzyme assays and multi-omics data further demonstrated that both Hg 2+ and MeHg elicited oxidative stress and impaired growth, development, and energy metabolism in brine shrimp. Integrated omics analysis revealed that glutathione metabolism is highly associated with Hg 2+ , while glycerophospholipid metabolism is highly associated with MeHg. Our study revealed the toxicity effects of mercury in zooplankton brine shrimp and promoted the understanding of the underlying mechanism and coping strategies for mercury toxicity in the zooplankton of the aquatic food chain.