Biodegradation of synthetic dye Alizarin Cyanine Green by yellow laccase producing strain Stropharia sp. ITCC-8422

The dye industries have exploded tremendously since industrialization, as the consumption increases pressure upon the industries to meet the demands. Thereby leading to release of toxic chemicals and effluents in the surrounding environment. Alizarin Cyanine Green (ACG) a toxic dye has its utility in various industries and after utilization remaining dye and intermediates are released as effluent. The treatment of ACG using photocatalytic mechanism has been studied however studies via biological treatment are still lacking. Thus, the present study emphasizes on biological treatment of ACG using yellow laccase producing strain Stropharia sp. ITCC-8422. The strain produced 13.5 U/L of yellow laccase and efficiently decolorized ACG (200 ppm) on the second day. The dye decolorization media was optimized using OFAT to determine maximum decolorization. The role of yellow laccase on ACG decolorization was determined and maxiumum decolorization at pH 5 (87.6%) and 40 degrees C (73.9%) was obtained after 10 min of incubation. The control and treated ACG was analysed for dye degradation by UV-spectra, XRD and FTIR and the presence of the compounds were confirmed by HR-LCMS. The ACG (mass = 622.574) was biodegraded into low molecular weight compounds (E)-2-methylglutaconic acid (m/z = 149.0213; mass = 144.0426), ethosuximide (m/z = 146.0585; mass = 141.0798) and leucinic acid (m/z = 155.0685; mass = 132.0793). Further the phytotoxicity studies revealed that the toxicity of treated ACG reduced as compared to untreated ACG.