Manganese (II) removal from aqueous solutions by Cladosporium halotolerans and Hypocrea jecorina

Abstract

Manganese (Mn) is toxic at higher concentrations requiring its removal before returning the wastewater to the environment. This article reported the Mn removal of two fungi strains isolated from mine wastewater. ITS rRNA region sequencing identified the fungi strains as Cladosporium halotolerans and Hypocrea jecorina. Mn2+ removal assays were performed in Sabouraud broth with 50 mg L−1 Mn2+ supplemented and bioleaching assays using MnO2 instead of MnSO4 at the same conditions. C. halotolerans removed 96 % of 50 mg L−1 Mn2+ at two weeks without MnO2 bioleaching with 649.9 mg of biomass and H. jecorina removed about 50 % of Mn2+ in 21 days from initial 50 mg of Mn2+ L-1 with 316.8 mg of biomass. Extracellular laccases were present in C. halotolerans agar regardless of the Mn addition. Mn adsorbed was detected on C. halotolerans hyphae. Mn oxidation was positive to H. jecorina by reaction of its medium with Leucoberbelin blue. Keywords: Hypocrea jecorina, Cladosporium halotolerans, Chelating, Manganese, Mn oxidation