Lead [Pb(II)] biosorption capacities of immobilized Talaromyces macrosporus on Moringa oleifera L. wood were compared against pure fungal and pure M. oleifera biomass. A Pb(II) contact test of 1000 ug/mL show similar Pb(II) removal of non-immobilized fungal biomass (F) and powdered wood colonized with fungi (WP+F), with WP+F producing more biomass. Powdered sorbents had higher Pb(II) uptake compared to whole sorbents analyzed through ICP-AES, possibly due to increased surface area for Pb(II) binding. FTIR analysis of the F, WP, and WP+F identified hydroxyl, amino, carbonyl, and sulfhydryl functional groups which constitute probable Pb(II)-affinitive binding sites. The biosorbents tested in a Continuous Flow Column (CF) adsorbed Pb(II) at 1000, 2000, and 4000 ug/mL in 30 minutes with the Pb(II) uptake of WP+F producing removal efficiencies at 91-95% regardless of initial Pb(II) concentration. WP+F also showed significantly higher q values than powdered wood (WP) at 42.67184.83 mg/g for the Pb(II) test concentrations. Recovery of Pb(II) from WP+F yielded 99.61% of adsorbed ions from 1000 ug/mL Pb(II), proving Pb(II) entrapment in the sorbent. This is the first study to describe biosorption capacities for T. macrosporus and M. oleifera softwood along with the wood’s viability as an immobilization scaffold. These results show the potential of using T. macrosporus immobilized on M. oleifera wood as a tool for removal of Pb(II) in wastewater with high Pb(II) concentrations.

The Lead [Pb(II)] tolerance and uptake ability of four fungal species, two from the genus Penicillium and two from the genus Talaromyces were investigated in this study. The species were isolated from a polluted tributary and identified to be closest to P. canescens, P. simplicissimum, T. macrosporus and another Talaromyces sp. via PCR targeting their internal transcribed spacer 1 and 4 sequences. All isolates have tolerances for up to 2000 µg/mL and 3000 µg/mL Pb(II) on solid and liquid medium, respectively. Both Penicillium isolates showed increasing removal rates dependent on initial Pb(II) concentration at 500 to 2000 µg/mL, while removal rates of both Talaromyces isolates were not significantly influenced by initial Pb(II) concentrations. The Pb(II) uptake of all isolates increased with increasing Pb(II) concentration but was depressed at 3000 µg/mL, with the exception of T. macrosporus. The recorded total uptake capacities for both Penicillium isolates in this study were higher than in most literature, at 7.0-407.4 mg/g and 50.8-412.6 mg/g for P. canescens and P. simplicissimum, respectively. The study also reported the exemplary Pb(II) uptake capacities of both Talaromyces isolates at 58.9-601.0 mg/g and 60.9-402.3 mg/g for T. macrosporus and Talaromyces sp., respectively. These results signify the excellent Pb(II) removal capabilities of all isolates which may further be developed for use as mycoremediation tools to remove Pb(II) from heavy metal contaminated environments.

No abstract