Reduced graphene oxide promotes the biodegradation of sulfamethoxazole by white-rot fungus Phanerochaete chrysosporium under cadmium stress

Lejie Pan; Yunxuan Hu; Zhixue Zhang; Yue Yuan; Qinmei Zhong; Sheng-Tao Yang

doi:10.1016/j.watres.2024.121558

Reduced graphene oxide promotes the biodegradation of sulfamethoxazole by white-rot fungus Phanerochaete chrysosporium under cadmium stress

Water Res. 2024 Jun 1:256:121558. doi: 10.1016/j.watres.2024.121558. Epub 2024 Apr 1.

Authors

Lejie Pan¹, Yunxuan Hu¹, Zhixue Zhang¹, Yue Yuan², Qinmei Zhong³, Sheng-Tao Yang⁴

Affiliations

¹ Key Laboratory of Pollution Control Chemistry and Environmental Functional Materials for Qinghai-Tibet Plateau of the National Ethnic Affairs Commission, School of Chemistry and Environment, Southwest Minzu University, Chengdu 610041, China.
² Key Laboratory of Pollution Control Chemistry and Environmental Functional Materials for Qinghai-Tibet Plateau of the National Ethnic Affairs Commission, School of Chemistry and Environment, Southwest Minzu University, Chengdu 610041, China; Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station, Southwest Minzu University, Chengdu 610041, China. Electronic address: smileyuan1987@swun.edu.cn.
³ Key Laboratory of Pollution Control Chemistry and Environmental Functional Materials for Qinghai-Tibet Plateau of the National Ethnic Affairs Commission, School of Chemistry and Environment, Southwest Minzu University, Chengdu 610041, China; Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station, Southwest Minzu University, Chengdu 610041, China.
⁴ Key Laboratory of Pollution Control Chemistry and Environmental Functional Materials for Qinghai-Tibet Plateau of the National Ethnic Affairs Commission, School of Chemistry and Environment, Southwest Minzu University, Chengdu 610041, China; Sichuan Zoige Alpine Wetland Ecosystem National Observation and Research Station, Southwest Minzu University, Chengdu 610041, China. Electronic address: yangst@swun.edu.cn.

PMID: 38604065
DOI: 10.1016/j.watres.2024.121558

Abstract

The biodegradation of antibiotics in aquatic environment is consistently impeded by the widespread presence of heavy metals, necessitating urgent measures to mitigate or eliminate this environmental stress. This work investigated the degradation of sulfamethoxazole (SMX) by the white-rot fungus Phanerochaete chrysosporium (WRF) under heavy metal cadmium ion (Cd²⁺) stress, with a focus on the protective effects of reduced graphene oxide (RGO). The pseudo-first-order rate constant and removal efficiency of 5 mg/L SMX in 48 h by WRF decrease from 0.208 h^-1 and 55.6% to 0.08 h^-1 and 28.6% at 16 mg/L of Cd²⁺, while these values recover to 0.297 h^-1 and 72.8% by supplementing RGO. The results demonstrate that RGO, possessing excellent biocompatibility, effectively safeguard the mycelial structure of WRF against Cd²⁺ stress and provide protection against oxidative damage to WRF. Simultaneously, the production of manganese peroxidase (MnP) by WRF decreases to 38.285 U/L in the presence of 24 mg/L Cd²⁺, whereas it recovers to 328.51 U/L upon the supplement of RGO. RGO can induce oxidative stress in WRF, thereby stimulating the secretion of laccase (Lac) and MnP to enhance the SMX degradation. The mechanism discovered in this study provides a new strategy to mitigate heavy metal stress encountered by WRF during antibiotic degradation.

Keywords: Biodegradation; Heavy metal stress; Reduced graphene oxide; Sulfamethoxazole; White-rot fungus.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Biodegradation, Environmental*
Cadmium* / metabolism
Graphite*
Phanerochaete* / metabolism
Sulfamethoxazole* / metabolism
Water Pollutants, Chemical / metabolism

Substances

Sulfamethoxazole
Cadmium
Graphite
graphene oxide
Water Pollutants, Chemical