Metal cation toxicity in the alga Gracilaria domingensis as evaluated by the daily growth rates in synthetic seawater

Autor(es)

Mendes, Luiz Fernando ^[1] ; Zambotti-Villela, Leonardo ^[1] ; Colepicolo, Pio ^[1] ; Marinho-Soriano, Eliane ^[2] ; Stevani, Cassius Vinicius ^[3] ; Yokoya, Nair Sumie ^[4]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Quim, Dept Bioquim, BR-05599970 Sao Paulo - Brazil

^[2] Univ Fed Rio Grande do Norte, Dept Oceanog & Limnol, BR-59072970 Natal, RN - Brazil

^[3] Univ Sao Paulo, Inst Quim, Dept Quim, Sao Paulo - Brazil

^[4] Nucleo Pesquisa Ficol, Inst Bot, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF APPLIED PHYCOLOGY; v. 25, n. 6, p. 1939-1947, DEC 2013.
• Citações Web of Science: 21

Resumo

Macroalgae of the genus Gracilaria have considerable economic importance as raw material for agar production and belong to an important group of organisms that are tolerant of high concentrations of metal. The median inhibitory concentration (IC50) values obtained by measuring the ratio of fresh mass variation (i.e., daily growth rates) of the red macroalga Gracilaria domingensis during a 48-h aquatic toxicity assay are reported here. The alga was exposed to 14 different metal cations as well as the molybdate anion in synthetic seawater. The actual concentrations of these ionic species (at IC50 values) and the proportion of free ions (aqueous complexes) were determined by inductively coupled plasma atomic emission spectroscopy and the Environmental Protection Agency-recommended software, MINTEQA2, respectively. Based on the free IC50 values (IC50 (F)), the ions were ranked in terms of toxicity: Cd2+ a parts per thousand << aEuro parts per thousand Cu2+ a parts per thousand << aEuro parts per thousand Pb2+ a parts per thousand << aEuro parts per thousand Zn2+ a parts per thousand << aEuro parts per thousand Ni2+ > Co2+ > La3+ a parts per thousand << aEuro parts per thousand Mn2+ > Ca2+ Li+ a parts per thousand << aEuro parts per thousand MoO4 (2-) a parts per thousand << aEuro parts per thousand Sr2+ > Mg2+ a parts per thousand << aEuro parts per thousand K+ > Na+. As a member of the first trophic level in the marine food chain, G. domingensis is an appropriate target organism both for the development of toxicological assays and as a bioindicator of marine degradation. (AU)

• Processo FAPESP: 09/54718-4 - Efeitos de metais mono-, bi e trivalentes sobre a fisiologia de algas
• Beneficiário: Luiz Fernando Mendes
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado