Physiological effects of sulfadiazine and sulfamethoxazole on Skeletonema costatum and toxicological evaluation using IBRv2 index

作者：Yurong Zhang, Tiejun Li, Yuxin Lin, Dongdong Xu, Haifeng Jiao · 发表于：Ecotoxicology and Environmental Safety · 年份：2025 · DOI：10.1016/j.ecoenv.2025.117881 · 被引用次数：11 · 研究领域：Pharmaceutical and Antibiotic Environmental Impacts、Environmental Toxicology and Ecotoxicology、Water Quality Monitoring and Analysis

Sulfonamide antibiotics, widely used in human and veterinary medicine as well as agriculture, pose environmental concerns due to their stability and poor biodegradability. This study fills a critical gap in understanding the ecological impact of sulfonamide antibiotics on marine microalgae, particularly Skeletonema costatum , a key primary producer in marine ecosystems. This study investigated the biological responses of the marine microalga Skeletonema costatum to sulfadiazine (SD) and sulfamethoxazole (SMX). Both antibiotics significantly impacted S. costatum , with SD having a more pronounced effect. Growth studies showed a clear dose-response relationship: Low concentrations (0.5 mg/L) of SD and SMX stimulated growth, while higher concentrations (3 mg/L, 5 mg/L, and 10 mg/L) inhibited growth. The 96-hour half-maximal inhibitory concentrations (96h-IC 50 ) were 1.654 mg/L and 1.838 mg/L, respectively, initially indicating that SD has a stronger inhibitory effect on S. costatum than SMX. Photosynthetic activity, measured by chlorophyll a content and the maximum quantum yield of photosystem II ( Fv/Fm ) values, showed that low concentrations (0.5 mg/L) of SD and SMX increased photosynthetic efficiency, while high concentrations (3 mg/L, 5 mg/L, and 10 mg/L) significantly inhibited it. Antioxidants activity analysis revealed that SD and SMX exposure altered superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and malondialdehyde (MDA) level...