Biosorption of lead (II) ion using Penicillium citrinum KR706304 isolated from the mangrove soil environment of southeast Borneo.

Abstract

The use of biological entities (fungi, bacteria, and algae) is considered to be a potential cost-effective and environmental friendly technique for heavy metals pollution sequestration. The present study aimed to isolate efficient lead tolerant fungi from mangrove soil environment and measure its capability for lead removal from aqueous solution. Lead tolerant fungal strains were isolated from soil samples using MEA (malt extract agar) amended with varied  concentrations of lead ions (100-500 mg l^-1 ). The most tolerant fungal strain was successfully isolated and identified molecularly as Penicillium citrinum KR706304 The isolated fungus was used for biosorption studies using malt extract broth (MEB) amended with lead ions. The effects of pH, temperature, initial metal concentration, biomass dose and age, agitation and contact time to the Pb(II) removal efficiency were monitored in the study.  The results showed that the lead removal was optimal at concentration of 400 mg l^-1 , maximum adsorption of   329±33.4 mg g^-1 was observed at pH 7 and temperature of 30^oC during the batch biosorption experiments. The  optimal parameters for biomass dose, agitation speed, contact time and biomass age were 0.04 g l^-1 , 150 rpm, 60 min and fifth day; respectively. The study revealed that the isolated Penicillium citrinum KR706304 has the potential to be used as a biosorbent for heavy metals particularly Pb(II) removal from the contaminated sites.

Keywords: Fungi, Heavy metals, Lead(II) removal, Penicillium citrinum.