chemosensors Article Red Seaweeds as a Source of Nutrients and Bioactive Compounds: Optimization of the Extraction Maria Carpena 1,2 , Cristina Caleja 1 , Eliana Pereira 1, Carla Pereira 1 , Ana Ciri´c´ 3 , Marina Sokovi´c 3 , Anton Soria-Lopez 1, Maria Fraga-Corral 1,2 , Jesus Simal-Gandara 2 , Isabel C. F. R. Ferreira 1 , Lillian Barros 1,* and Miguel A. Prieto 1,2,* 1 Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal;
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[email protected] (I.C.F.R.F.) 2 Nutrition and Bromatology Group, Ourense Campus, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, E-32004 Ourense, Spain;
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[email protected] (M.A.P.) Abstract: The present work aimed to determine the nutritional composition (ash, protein, fat, car- bohydrate content and energy value), phenolic compounds, pigments and organic acids content of three typical red algae from the Northwest of Spain: Chondrus crispus, Mastocarpus stellatus, and Gigartina pistillata; as well as their antioxidant and antimicrobial activities. Furthermore, the present Citation: Carpena, M.; Caleja, C.; work compared two extraction techniques: conventional heat assisted extraction (HAE) and high Pereira, E.; Pereira, C.; Ciri´c,A.;´ pressure assisted extraction (HPAE) to maximize the yield and the concentration of target compounds.