A New Application for Klebsiella oxytoca in Bioremediation: Treatment of Manganese-Laden Wastewaters

Bioremediation is a method of removing manganese from wastewaters, and many bacterial species with a role in manganese bioremediation have been identified over several decades. Using K medium with Mn(II), a bacterial consortium was obtained from water sample collected from a mine drainage in southeastern Brazil (Minas Gerais, Brazil), and the isolates were identified as Klebsiella oxytoca using both biochemical and 16S rRNA phylogenetic analysis. Among such isolates, sample SA8 was tested for its manganese removal capability during a week-long experiment in K medium amended with manganese sulfate. Growth of isolate SA8 produced an increase in pH concomitantly to Mn(II) removal, which was not observed in the abiotic control. Manganese removal occurred through oxidation as confirmed by reaction with leucoberbelin blue, and therefore, a new potential application for K. oxytoca in mine water bioremediation is proposed.