Can titanium dioxide nanoparticles modulate the effects of zinc oxide nanoparticles on aquatic leaf litter decomposition?

Jingjing Du; Xilin Wang; Yuyan Zhang; Gaozhong Pu; Baodan Jin; Wenrui Qv; Xia Cao

doi:10.1016/j.chemosphere.2023.139313

Can titanium dioxide nanoparticles modulate the effects of zinc oxide nanoparticles on aquatic leaf litter decomposition?

Chemosphere. 2023 Oct:337:139313. doi: 10.1016/j.chemosphere.2023.139313. Epub 2023 Jun 22.

Authors

Jingjing Du¹, Xilin Wang², Yuyan Zhang², Gaozhong Pu³, Baodan Jin⁴, Wenrui Qv², Xia Cao⁵

Affiliations

¹ School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan Province, China. Electronic address: Dujj@zzuli.edu.cn.
² School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China.
³ Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin, China.
⁴ School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan Province, China.
⁵ School of Materials and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, China; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Henan Province, China. Electronic address: 2020003@zzuli.edu.cn.

PMID: 37354960
DOI: 10.1016/j.chemosphere.2023.139313

Abstract

The potential impacts of metallic nanoparticles (NPs) at environmental levels on freshwater ecosystems cannot be ignored due to their frequent release. The most widely used metallic oxide, ZnO NPs and TiO₂ NPs (100 ng L^-1) were applied to explore their single and combined effects on leaf litter decomposition. Although ZnO NPs and TiO₂ NPs alone or in combination increased 22.68%-41.17% of the leaf decomposition rate, they performed different toxic mechanisms in ecological processes. The microbial mass and enzyme activities significantly increased after acute exposure, but significantly decreased after chronic exposure to ZnO NPs. The activity of BG was the most sensitive factor that was decreased by 66.22%, 56.97%, and 39.39% after 21-day exposure to ZnO NPs, TiO₂ NPs, and in combination, respectively. In addition, the analysis of Fourier transform infrared spectroscopy suggested a novel perspective on understanding the promoting mechanism. The promotion effect of ZnO NPs relied on the enhanced decomposition of refractory organics and easily degradable substances due to the contribution of Anguillospora, Pyrenochaetopsis, and Bipolaris. The single exposure to TiO₂ NPs and combined exposure with ZnO NPs promoted microbial mass and hydrolase activities, with the stimulating effect attributed to the enhanced decomposition of soluble substances. Therefore, the results highlight the importance of chemical analysis of decomposed leaves to evaluate the potential threat of metallic NPs to the function of freshwater ecosystems.

Keywords: Chemical functional groups; Freshwater ecosystems; Fungal community; Microbial biomass.

MeSH terms

Ascomycota*
Ecosystem
Metal Nanoparticles* / toxicity
Nanoparticles* / chemistry
Plant Leaves
Titanium / toxicity
Zinc Oxide* / toxicity

Substances

Zinc Oxide
titanium dioxide
Titanium