Development of Leptospirillum ferriphilum dominated consortium for ferric iron regeneration and metal bioleaching under extreme stresses

• Published in: Bioresource technology 2012-08, Vol.118, p.483-489
• Main Authors: Patel, Bhargav C., Tipre, Devayani R., Dave, Shailesh R.
• Format: Article
• Language: English
• Subjects: Bacteria - genetics; Bacteria - metabolism; Bacterial leaching; Bioleaching; Copper; Copper - isolation & purification; Denaturing Gradient Gel Electrophoresis; DGGE; Digestion; Electrophoresis, Agar Gel; Ferric regeneration; Genes; Iron; Iron - metabolism; Leptospirillum ferriphilum; Microbial Consortia; Molecular Sequence Data; Oxidation-Reduction; Restriction digestion; Restriction Mapping; RNA, Ribosomal, 16S - genetics; Sodium; Stress, Physiological; Sulfates; Water Pollutants, Chemical - isolation & purification; Zinc; Zinc - isolation & purification
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2012.05.094

► Developed consortium SR-BH-L gave iron oxidation rate 1954mg/L/h in SDB1 medium. ► It oxidized Fe2+ under major stress of 7.47M ionic strength, 2.3 pH and 393.8 TDS. ► It showed 78.0% and 70.0% copper and zinc extraction from PBC. ► DGGE analysis indicated the presence of 11 OTUs in the consortium. ► RE digestion analysis of 16S rDNA showed dominance of Leptospirillum ferriphilum. Activated iron oxidizing consortium SR-BH-L enriched from Rajpardi lignite mine soil sample gave iron oxidation rate 1954mg/L/h. Developed novel polystress resistant consortium oxidized ferrous iron under 11cP viscosity, 7.47M ionic strength, 2.3 pH and g/L of 0.50 cadmium, 3.75 copper, 0.20 lead, 92.00 zinc, 6.4 sodium, 5.5 chloride, 154 sulphate and 393.8 TDS. The developed consortium showed 78.0% and 70.0% copper and zinc extraction from polymetallic bulk concentrate in monophasic bioleaching process. The bioregenerated ferric by the consortium in leachate showed 80.81% and 54.0% copper and zinc leaching in only 30 and 90min. The DGGE analysis indicated the presence of 11 OTUs in the consortium. 16S rRNA gene sequence (JN797729) of the dominant band on DGGE shared >99% similarity with Leptospirillum ferriphilum. RE digestion analysis of the total 16S rRNA gene also illustrated the dominance of L. ferriphilum in the consortium.