Glucose as a Metabolic Enhancer: Promoting Nonylphenol Detoxification by Chlorella pyrenoidosa

The environmental treatment of endocrine-disrupting compounds (EDCs) has attracted significant attention. Nonylphenol (NP), a highly toxic EDC with widespread distribution, presents an urgent challenge requiring effective removal strategies. Although microalgae-based treatments offer environmentally friendly and cost-effective solutions, the high toxicity level of NP impedes this process. Analysis was conducted on cell biomass, cell morphology, extracellular polymeric substances (EPSs), and the degradation of nonylphenol in Chlorella pyrenoidosa treated with nonylphenol and glucose. Glucose restored the algal biomass to 2.23 times its original level, reduced cellular damage, and maintained normal physiological activities. Glucose also stimulated algal metabolism and promoted the secretion of EPSs. The polysaccharide content of soluble EPSs (S-EPSs) increased by 32.7%, whereas that of the bound EPSs (B-EPSs) increased by 55.5%. The three-dimensional excitation–emission matrix fluorescence spectroscopy of B-EPS indicated that glucose enhanced tryptophan secretion. Glucose showed great potential as a biostimulant to enhance NP bioremediation efficiency in aquatic ecosystems. This finding indicates that the nonylphenol remediation of wastewater can be integrated with microalgal biomass recovery, creating opportunities for revenue generation.