title: Population studies and carrageenan properties in eight Gigartinales (Rhodophyta) from Western Coast of Portugal.
abstract: Eight carrageenophytes, representing seven genera and three families of Gigartinales (Florideophyceae), were studied for 15 months. The reproductive status, dry weight, and carrageenan content have been followed by a monthly random sampling. The highest carrageenan yields were found in Chondracanthus acicularis (61.1%), Gigartina pistillata (59.7%), and Chondracanthus teedei var. lusitanicus (58.0%). Species of Cystocloniaceae family produces predominantly iota-carrageenans; Gigartinaceae family produces hybrid kappa-iota carrageenans (gametophytic plants) and lambda-family carrageenans (sporophytic plants); Phyllophoraceae family produces kappa-iota-hybrid carrageenans. Quadrate destructive sampling method was used to determine the biomass and line transect. Quadrate nondestructive sampling method, applied along a perpendicular transect to the shoreline, was used to calculate the carrageenophytes cover in two periods: autumn/winter and spring/summer. The highest cover and biomass were found in Chondrus crispus (3.75%-570 g/m(2)), Chondracanthus acicularis (3.45%-99 g/m(2)), Chondracanthus teedei var. lusitanicus (2.45%-207.5 g/m(2)), and Mastocarpus stellatus (2.02%-520 g/m(2)).
authors.affiliation: Institute of Marine Research (IMAR-CMA), Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, 3001-455 Coimbra, Portugal.
authors.forename: Leonel
authors.initials: L
authors.lastname: Pereira
mesh_terms: D018533:Biomass; D002351:Carrageenan / Q000032:analysis*; D011174:Portugal; D000461:Rhodophyta / Q000737:chemistry* / Q000145:classification / Q000502:physiology
chemical_list: D002351:Carrageenan