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White rot fungi (WRF) produce various isoforms of extracellular peroxidases (lignin peroxidase-LiP and manganese peroxidase-MnP) and phenoloxidases (laccases), which are involved in the degradation of lignin in their natural lignocellulosic substrates. This ligninolytic system of WRF is directly involved in the degradation of various xenobiotic compounds and dyes. Liquid fermentation or solid-state fermentation techniques can be used for enzyme production. Crude enzymes or purified enzymes of WRF can be used for decolorization of azo dyes. Repeated-batch decolorization technique is a new approach that can be used for decolorization. There are different procedures to determine the enzyme(s) responsible for decolorization. Single step isolation and identification procedure (SSIIP) is a new and simple method that can be used for detection of the enzyme responsible for biodegradation of azo dyes.

Funalia trogii was used for the first time for the removal of bisphenol A (BPA), a well known endocrine disrupting compound. Biodegradation efficiencies of commercial pure laccase from Trametes versicolor, crude extract of F. trogii and the mixture of pure laccase from T. versicolor, and thermally inactivated crude extract of F. trogii were compared. BPA was completely removed by both the crude extract and with mixture whereas only 30% was removed with pure laccase. The results showed the presence of mediator molecules in the crude extract of F. trogii and also confirm the role of laccase in BPA biodegradation. A mediator molecule, butylhydroxytoluene, was detected by GC‐MS analysis of the crude extract of F. trogii. The results also proved unnecessity of enzyme isolation procedures for the enzymatic biodegradation of BPA. The BPA concentration was analyzed by HPLC and metabolites of BPA were characterized by GC‐MS. The results of both analyses were correlated and BPA was completely removed after 2 h of incubation time. The reaction maximum velocity and Km values obtained from Lineweaver–Burk plots of Michaelis–Menten equation were 7.43 mg L−1 min−1 and 66.35 mg/L, respectively. The acute toxicity of BPA and its products after 6 h incubation period was 98.9 ± 1.0 and 7.5 ± 0.4%, respectively. The results of this study point out the use of an alternative feasible method for the complete removal of BPA from polluted environments.

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