The present study was carried out to determine the antitumor and antioxidant activities of the seaweed Durvillaea antarctica. Extraction and purification of polysaccharides from D. antarctica were performed.
View Article and Find Full Text PDFPhotosynthesis, growth and biochemical composition of the biomass of the freshwater microalga Chlamydopodium fusiforme cultures outdoors in a thin-layer cascade were investigated. Gross oxygen production measured off-line in samples taken from the outdoor cultures was correlated with the electron transport rate estimated from chlorophyll a fluorescence measurements. According to photosynthesis measurements, a mean of 38.
View Article and Find Full Text PDFThe red macroalgae Hydropuntia cornea, Gracilariopsis longissima and Halopithys incurva were cultured for 14 d under laboratory conditions, in enriched seawater with a high nutrient content (N-NH and P-PO ) and two radiation regimes: PAR (400-700 nm) and PAB (280-700 nm). The UV radiation effects under high availability of nutrients on growth, photosynthetic pigments (chlorophyll a, carotenoids and phycobiliproteins), photosynthetic activity and biochemical composition were studied. Maximum quantum yield (F /F ) was not significantly different among the PAR and PAB treatments during the experiment.
View Article and Find Full Text PDFPhotochem Photobiol
July 2019
Acanthophora spicifera (M.Vahl) Børgesen is a macroalga of great economic importance. This study evaluated the antioxidant responses of two algal populations of A.
View Article and Find Full Text PDFThis study was designed to evaluate the potential use of algal extracts in cosmeceuticals, including factors related to biosecurity. The aqueous crude extracts of and showed a good photoprotective capacity (Sun Protection Factor, SPF) due to, among other reasons, the presence of five types of mycosporine-like amino acids (MAAs) detected by high pressure liquid chromatography-photodiode array detector (HPLC-PDA) and electrospray ionization mass spectrometry (ESI-MS) (Palythine, Asterina-330, Shinorine, Porphyra-334, and Palythinol). The toxicity of the extracts was evaluated by the MTT assay, which is based on the metabolic reduction of MTT [3-(4,5-dimethylthiazol-2yl)-diphenyl tetrazolium bromide] by the action of the mitochondrial enzyme succinate dehydrogenase.
View Article and Find Full Text PDFMar Drugs
January 2019
The safety and stability of synthetic UV-filters and the procedures for evaluating the photoprotective capability of commercial sunscreens are under continuous review. The influence of pH and temperature stressors on the stability of certain Mycosporine-like amino acids (MAAs) isolated at high purity levels was examined. MAAs were highly stable at room temperature during 24 h at pH 4.
View Article and Find Full Text PDFThis study evaluates the production of biomass and mycosporine-like amino acids (MAAs) throughout the year in Gracilaria vermiculophylla (Rhodophyta) collected in Ria de Aveiro (Portugal). The algae were grown in outdoor tanks in seawater with the addition of fishpond effluents under two different water flows (100 and 200 L h) in an integrated multi-trophic aquaculture (IMTA) system (tanks 1200 L; 1.5 m) and different algal densities (3, 5, and 7 kg m).
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