Development of immobilized novel fungal consortium for the efficient remediation of cyanide-contaminated wastewaters
Saloni Rishi, Ispreet Kaur, Mariya Naseem, Vivek Kumar Gaur, Sandhya Mishra, Suchi Srivastava, Harvinder Singh Saini, Pankaj Kumar Srivastava
Abstract
Free cyanide is a hazardous pollutant released from steel industries. Environmentally-safe remediation of cyanide-contaminated wastewater is required. In this work, Pseudomonas stutzeri (ASNBRI_B12), Trichoderma longibrachiatum (ASNBRI_F9) , Trichoderma saturnisporum (ASNBRI_F10) and Trichoderma citrinoviride (ASNBRI_F14) were isolated from blast-furnace wastewater and activated-sludge by enrichment culture. Elevated microbial growth, rhodanese activity (82 %) and GSSG (128 %) were observed with 20 mg-CN L −1 . Cyanide degradation > 99 % on 3rd d as evaluated through ion chromatography, followed by first-order kinetics (r 2 = 0.94–0.99). Cyanide degradation in wastewater (20 mg-CN L −1 , pH 6.5) was studied in ASNBRI_F10 and ASNBRI_F14 which displayed increased biomass to 49.7 % and 21.6 % respectively. Maximum cyanide degradation of 99.9 % in 48 h was shown by an immobilized consortium of ASNBRI_F10 and ASNBRI_F14. FTIR analysis revealed that cyanide treatment alters functional groups on microbial cell walls. The novel consortium of T. saturnisporum - T. citrinoviride in the form of immobilized culture can be employed to treat cyanide-contaminated wastewater.