Analysis of photosynthetic pigments and phenolic compounds in Gracilariopsis tenuifrons (C.J. Bird &E.C. Oliveira) Fredericq &Hommersand at different light intensities / Análise de pigmentos fotossintetizantes e substâncias fenólicas em Gracilariopsis tenuifrons (C. J. Bird &E. C. Oliveira) Fredericq &Hommersand em diferentes intensidades de luz
AUTOR(ES)
Priscila Bezerra Torres
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
03/08/2012
RESUMO
The high-light stress can adversely affect growth and development of photosyn-thetic organisms. In these situations, it is common to note chemical responses that may indicate different strategies of photoprotection. In this study, protocols were optimized for analysis and extraction of phenolic compounds and photosynthetic pig-ments in macrophytic red algae Gracilariopsis tenuifrons in order of evaluat-ing the effects of high-light stress on these compounds. It was found that an increase in light intensity has not caused decrease in biomass of algae; on the contrary, promotes a greater increase in biomass. Zeaxanthin, β-carotene and chlorophyll α were the major pigments present in the extract. The β-carotene and chlorophyll a were inversely dependent on the intensity of light. Both pigments were highly correlated sug-gesting the same role in photosynthesis. The concentration of the zeaxanthin was de-pendent on the intensity of light in the initial days, indicating a photoprotection function for this pigment. The reduction capacity of the extract increased with light intensity. However, it was not possible to state that this increase was actually due to the synthesis of phenolic compounds or other substances that perform the same role. The HPLC ana-lyzes revealed that a derivative of micosporina palitinol showed high correlation with the increase in light intensity. This response was highly correlated with the results for Folin-Ciocalteu assay. In conclusion, from all compounds analyzed in this work, zeax-anthin and the palitinol derivative presented clearer results as antioxidants
ASSUNTO(S)
folin-ciocalteu folin-ciocalteu gracilariopsis tenuifrons gracilariopsis tenuifrons intensidade de luz light intensity micosporinas mycosporines photosynthetic pigments pigmentos fotossintetizantes
