Cylindrospermopsin induced changes in growth, toxin production and antioxidant response of Acutodesmus acuminatus and Microcystis aeruginosa under differing light and nitrogen conditions

Autor(es)

Chia, Mathias Ahii ; Cordeiro-Araujo, Micheline Kezia ; Lorenzi, Adriana Sturion ; Bittencourt-Oliveira, Maria do Carmo

• Tipo de documento: Artigo Científico
• Fonte: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY; v. 142, p. 189-199, AUG 2017.
• Citações Web of Science: 5

Resumo

Growing evidence suggests that some bioactive metabolites (e.g. cyanotoxins) produced by cyanobacteria have allelopathic potential, due to their inhibitory or stimulatory effects on competing species. Although a number of studies have shown that the cyanotoxin cylindrospermopsin (CYN) has variable effects on phytoplankton species, the impact of changing physicochemical conditions on its allelopathic potential is yet to be investigated. We investigated the physiological response of Microcystis aeruginosa (Cyanobacteria) and Acutodesmus acuminates (Chlorophyta) to CYN under varying nitrogen and light conditions. At 24 h, higher microcystins content of M. aeruginosa was recorded under limited light in the presence of CYN, while at 120 h the lower levels of the toxins were observed in the presence of CYN under optimum light. Total MCs concentration was significantly (p < 0.05) lowered by CYN after 120 h of exposure under limited and optimum nitrogen conditions. On the other hand, there were no significant (p > 0.05) changes in total MCs concentrations after exposure to CYN under high nitrogen conditions. As expected, limited light and limited nitrogen conditions resulted in lower cell density of both species, while CYN only significantly (p < 0.05) inhibited the growth of M. aeruginosa. Regardless of the light or nitrogen condition, the presence of CYN increased internal H2O2 content of both species, which resulted in significant (p < 0.05) changes in antioxidant enzyme (catalase, peroxidase, superoxide dismutase and glutathione S-transferase) activities. The oxidative stress caused by CYN was higher under limited light and limited nitrogen. These results showed that M. aeruginosa and A. acuminates have variable response to CYN under changing light and nitrogen conditions, and demonstrate that need to consider changes in physicochemical conditions during ecotoxicological and ecophysiological investigations. (AU)

• Processo FAPESP: 13/11306-3 - Efeitos de anatoxina-a e cilindrospermopsina em diferentes concentrações de nitrogênio e irradiância na fisiologia de Microcystis aeruginosa (Cyanobacteria)e Scenedesmus acuminatus (Chlorophyta)
• Beneficiário: Mathias Ahii Chia
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/15296-2 - Metagenômica comparativa de florações de cianobactérias em reservatórios de água do estado de Pernambuco
• Beneficiário: Adriana Sturion Lorenzi
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 15/17397-6 - RITMO CIRCADIANO NA PRODUÇÃO E LIBERAÇÃO DE MICROCISTINAS, EXPRESSÃO DO GENE mcyE E ESTRESSE FISIOLÓGICO EM CIANOBACTÉRIAS: IMPLICAÇÕES DAS MUDANÇAS CLIMÁTICAS GLOBAIS
• Beneficiário: Micheline Kézia Cordeiro de Araújo
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/26898-6 - Revelando alguns processos fisiológicos e moleculares envolvidos nas interações alelopáticas entre fitoplâncton tóxico e não-tóxicos
• Beneficiário: Mathias Ahii Chia
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 14/01934-0 - Investigação de bioacumulação e desintoxicação de toxinas de cianobactérias (microcistinas e cilindrospermopsina) em alface e rúcula
• Beneficiário: Maria Do Carmo Bittencourt de Oliveira
• Modalidade de apoio: Auxílio à Pesquisa - Regular