Biodegradation of malachite green by Pleurotus eryngii: A study on decolorization, mechanism, toxicity, and enzyme

Abstract The purpose of this study was to investigate the biodegradation capability of Pleurotus eryngii through decolorizing malachite green (MG), explore the possible mechanism, and test the toxicity. The results indicated that this strain possessed a high decolorizing ability. The intermediates of MG degradation identified by UPLC-TOF-Triple-MS analysis included 4-(dimethylamino)benzophenone, 4-(methylamino)benzophenone, and 4-(dimethylamino)phenol. Moreover, toxicity testing on the zebrafish animal model demonstrated a significant reduction in the toxicity of the degradation products. A newly discovered dye-decolorizing peroxidase (DyP-PE) from P. eryngii was amplified, cloned, and expressed. A 56.4 kDa protein of DyP-PE was purified, and this enzyme exhibited good decolorizing properties of MG. Therefore, this strain could potentially be used for the bioremediation of MG pollution, and the DyP-PE in P. eryngii may contribute to the degradation of MG.