Eco-friendly detoxification of hazardous Congo red dye using novel fungal strain Trametes flavida WTFP2: Deduced enzymatic biomineralization process through combinatorial in-silico and in-vitro studies

Abstract

Growing textile industry is a major global concern, owing to the presence of recalcitrant hazardous pollutants, like synthetic dyes in discharged effluents. To explore new bioresources for mycoremediation, a high laccase-producing novel white-rot fungus (WRF), Trametes flavida WTFP2, was employed. T. flavida is an underexplored member of Polyporales. Using bioinformatic tools, 8 different cis-acting RNA elements were identified in the 5.8 S ITS gene sequence, where CRISPR (CRISPR-DR15), sRNA (RUF1), and snoRNA (ceN111) are uniquely present. Molecular docking was adopted to predict the catalytic interaction of chosen toxic diazo colorant, Congo red (CR), with four dye-degrading enzymes (laccase, lignin peroxidase, azoreductase, and aryl alcohol oxidase). With 376.41 × 103 U/L laccase production, novel WRF exhibited dye-decolorization potential. WTFP2 effectively removed 99.48 ± 0.04% CR (100 mg/L) and demonstrated remarkable recyclability and persistence in consecutive remediation trials. Mycelial dye adsorption was not only substantial driver of colorant elimination; decolorization using active T. flavida was regulated by enzymatic catalysis, as outlined by in-vitro growth, induction of extracellular enzymes, and FESEM. Fifteen metabolites were identified using HRLCMS-QTOF, and novel CR degradation pathway was proposed. Furthermore, microbial and phyto-toxicity tests of metabolites suggested complete detoxification of toxic dye, making the process clean, green, and economically sustainable.