Exploring industrial effluent-derived bacterial isolate for enhanced biodegradation of bisphenol-A

Bisphenol A (BPA), a widespread endocrine-disrupting chemical and an emerging environmental contaminant, poses significant threats to ecosystems and human health. The present study identifies a bacterial strain affiliated with Enterobacteriaceae family Silvania sp. (GenBank Accession No. PP930832) isolated from industrial effluent, capable of efficiently degrading BPA. High-Performance Liquid Chromatography (HPLC) analysis confirmed the strain's degradation potential of 62% within 24 h at a concentration of 500 mg/L. Optimization by Design Expert 12.0 resulted in optimum values of pH 9.0, temperature 37.07°C, and inoculum concentration (4% v/v). Mass spectrometric analysis revealed the formation of putative intermediate metabolites during BPA degradation, including ions tentatively assigned to benzoic acid - related aromatic fragments, along with additional low-molecular-weight products indicative of progressive aromatic ring cleavage. The biodegradation pathway is proposed to proceed via enzymatic hydroxylation and oxidation reactions, leading to structural destabilization of BPA and its conversion into benzoic acid as a key intermediate. Subsequent transformations may yield cyclohexa-1,3-diene like intermediates that could potentially enter central metabolic pathway such as the β-ketoadipate and tricarboxylic acid (TCA) pathways. However, complete mineralization to CO₂ and H₂O was not directly verified in this study. These findings underscore the potential applicability of isolated species as an effective biological agent for BPA remediation and highlight its promise for sustainable environmental cleanup strategies.