Publications by authors named "Daniel Barroso de Alencar"

Objective: To evaluate the antioxidant, antibacterial and bacterial cell agglutination activities of the hexane (Hex) and 70% ethanol (70% EtOH) extracts of two species of red seaweeds Pterocladiella capillacea (P. capillacea) and Osmundaria obtusiloba.

Methods: In vitro antioxidant activity was determined by DPPH radical scavenging assay, ferric-reducing antioxidant power assay, ferrous ion chelating assay, β-carotene bleaching assay and total phenolic content quantification.

View Article and Find Full Text PDF

A new chromophore-containing agglutinin (Haliclona manglaris agglutinin (HMA)) was isolated from the tropical sponge H. manglaris. HMA was purified by a combination of hydrophobic interaction chromatography and ion exchange chromatography.

View Article and Find Full Text PDF

This study evaluated the effect of derriobtusone A, a flavonoid isolated from Lonchocarpus obtusus, on two important pathogenic bacteria, Staphylococcus aureus and Escherichia coli, as well as its antioxidant activity and toxicity. Planktonic growth assays were performed, and the inhibition of biofilm formation was evaluated. In addition, antioxidant activity was assessed by DPPH radical scavenging assay, ferrous ion chelating assay, ferric-reducing antioxidant power assay, and β -carotene bleaching assay.

View Article and Find Full Text PDF

Marine algae are a promising source of beneficial compounds for human use. Among these, pro-vitamin A carotenoids and vitamins B, C, and E stand out. The objective of this study was to investigate seasonal variation of α-tocopherol levels in 5 species of green marine algae of the Caulerpa genus.

View Article and Find Full Text PDF