In this work the adsorption capacity of the macrophyte Eichhornia crassipes (aguapé) biomass was evaluated in synthetic effluent containing Cd, Pb, Cr, Zn and Co metal ions. At first, the specific surface areas of each part of the plant (stem, leaf and root) were determined. The root was the selected part and then chemically activated HCl and 0.1 mol L-1 NaOH. The HCl activated root was used for the studies of the adsorption parameters: pH, contact time and initial concentration of the solution influence. In order to determine the concentration of the Cd and Pb ions the analytical method graphite furnace atomic absorption was used and to analyze Co, Zn and Cr, instrumental neutron R1

A demanda crescente por água tem feito de seu reuso planejado um tema atual e de grande importância. A reutilização de água pode ser direta ou indireta, decorrente de ações planejadas ou não. Íons metálicos podem ser removidos de soluções aquosas por processos como filtração, flotação, membranas de troca iônica, extração com solventes, eletrodeposição, coagulação e adsorção. Essa última pode ser considerada um método efetivo e barato quando comparado aos demais. Nos últimos anos, a utilização de materiais alternativos de alta capacidade de adsorção, como argila e biomassa, tem sido estudada para esta finalidade. Uma forma de determinar a eficiência de um material como adsorvente é por meio de isotermas de adsorção que indicam a quantidade máxima de material que pode

Marine biofouling is a natural process by which many organisms colonize and grow in submerged structures, causing serious economic consequences for the maritime industry. Geniculate calcareous algae (GCA; Corallinales, Rhodophyta) produce bioactive secondary metabolites and are a promise for new antifouling compounds. Here, we investigated the antifouling activity of four GCA species—Amphiroa beauvoisii, Jania sagittata (formerly Cheilosporum sagittatum), Jania crassa, and Jania prolifera (formerly Amphiroa flabellata)—from the Brazilian coast against macro- and microorganisms. Simultaneously, metabolomic tools were applied to assess the chemical profiles of these seaweeds using gas chromatography coupled to mass spectrometry (GC-MS). Data analysis by principal component and molecular networking analyses used the global natural products social molecular networking platform (GNPS). Our results showed that all extracts were active against different strains of marine bacteria and that the J. sagittata (JsSI) extract showed the highest percentage of bacterial inhibition. The J. sagittata (JsSI) extract was the most active against the mussel Perna perna, showing 100% byssus inhibition. Regarding toxicity, only the J. crassa (JcP) extract showed a 20% mortality rate. The chemical profiles of the evaluated GCA extracts differed qualitatively and quantitatively. Yet, the steroid (3β)-cholest-5-en-3-ol was the major compound commonly identified in all extracts, with the exception of J. sagittata (JsSI). Moreover, we observed intra- and interspecific chemical variabilities among GCA extracts for the different populations, which could explain their antifouling activity variability. This study contributed new information about the chemical compounds produced by this group of seaweeds and showed its antifouling potential. These GCA species may be the subject of future studies to obtain new bioactive compounds with biotechnological potential in maritime areas.