Carrageenan properties and proximate composition of three morphotypes of Kappaphycus alvarezii Doty (Gigartinales, Rhodophyta) grown at two depths

Abstract

Three morphotypes (brown, green and red) of Kappaphycus alvarezii grown at two depths were evaluated for carrageenan properties and proximate composition. The green morphotype was significantly different from the brown and red in all carrageenan properties except for sulfate content at 50 cm below the water surface; and significantly different only from the brown at 100 cm. Except for ash content and nitrogen free extract there were no significant differences in proximate composition (nitrogen, crude protein, crude fat, crude fiber) among the three morphotypes.