Copper biosorption from an aqueous solution by the dead biomass of Penicillium ochrochloron.

The present study investigated the effect of contact time, the initial concentration of metal ions, and the biomass dose on the Cu(II) biosorption from an aqueous solution using dead biomass of filamentous fungus Penicillium ochrochloron, which was isolated at the Sossego mine, a copper-contaminated site located in Canaã dos Carajás city, Brazil. The Cu(II) biosorption started rapidly and increased gradually until the equilibrium was reached at 20 min. The Cu(II) uptake decreased as the initial Cu(II) concentration increased, reaching the saturation at 200 mg/L. The Cu(II) biosorption was considerably higher using 0.2 g than 0.5 g of the biomass in 50 mL of solution. The average biosorption capacity of Cu(II) was 7.53 mg/g and the maximum Cu(II) removal 75.0%. The Freundlich and Langmuir isotherm models adequately described the adsorption data. Our results evidenced that the dead biomass of P. ochrochloron has a great potential as a biosorbent to remove copper from an aqueous solution. Therefore, it could be explored for the development of the environmental recovery process.

Isolation of Bisphenol A-Tolerating/degrading Shewanella haliotis Strain MH137742 from an Estuarine Environment.

The human exposure to bisphenol A (BPA) occurs frequently. Once, this compound was one of the highest volume chemicals produced worldwide and used as a plasticizer in many products. However, even at low concentration, it can cause severe damage to the endocrine system because of its endocrine disruptor activity. Thus, mitigation studies to remove or reduce this contaminant from the environment are essential. An alternative method of removing it from the environment is the use of bioremediation processes to the selected bacteria isolated from a BPA-impacted area. In this work, four halotolerant strains were isolated from the Santos Estuary System, one of the most important Brazilian examples of environmental degradation. In the present work, one strain presented strong BPA tolerance and high BPA-degrading activity and could grow in a minimum medium containing BPA as the main carbon source. Strain MH137742 was identified as Shewanella haliotis, based on 16S rRNA gene sequencing and mass spectrometry identification by MALDI-TOF Biotyper. Shewanella haliotis was able to tolerate up to 150 mg L-1 of BPA and biotransform 75 mg L-1 in 10 h in a liquid culture medium. Based on the analysis of the produced metabolites by LC-MS, it was possible to predict the metabolic pathway used by this microorganism to degrade the BPA.