Data/hora: 11/06/2024 02:24:33

Provedor de dados: | 61
País: | Brazil
Título: | Effect of cobalt on growth, pigments and the photosynthetic electron transport in Monoraphidium minutum and Nitzchia perminuta
Autores: | El-Sheekh,M.M.; El-Naggar,A.H.; Osman,M.E.H.; El-Mazaly,E.
Data: | 2003-12-01
Ano: | 2003
Palavras-chave: | Cobalt; Diatoms; Green algae; Pigments; Photosynthesis.
Resumo: | The unicellular green alga Monoraphidium minutum and the diatom Nitzschia perminuta were cultured under different concentrations of Co2+. Growth and pigment content were slightly increased at low concentrations and inhibited by high Co2+ concentrations. The results concerning the effect of different concentrations of Co2+ on photosynthetic O2 evolution showed a reduction in the amount of O2 evolved by each alga in response to increasing Co2+ concentrations. However, an increase in O2 evolution for both M. minutum and N. perminuta was observed at relatively low Co2+ concentrations. Photosynthetic electron transport in M. minutum was more sensitive to Co2+ toxicity than in N. perminuta. On the other hand, the effect of the heavy metal on respiration showed that higher Co2+ concentrations were inhibitory to O2 uptake by the two algal species. Low Co2+ concentrations stimulated O2 uptake by M. minutum throughout the experimental period. However, in N. perminuta, different concentrations of Co2+ led to a reduction of O2 uptake. To localize the action site of Co2+ in the photosynthetic electron transport chain, the fluorescence induction technique was carried out. According to the results obtained, the inhibitory action of Co2+ is located on the acceptor side of PSII for both M. minutum and N. perminuta.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202003000300005
Editor: | Brazilian Journal of Plant Physiology
Relação: | 10.1590/S1677-04202003000300005
Formato: | text/html
Fonte: | Brazilian Journal of Plant Physiology  v.15 n.3 2003
Fonte: | info:eu-repo/semantics/openAccess