The carrageenan system of Gigartina skottsbergii S. et G. Part II. Analysis of the system and studies on the structure of the fraction precipitated at 0·3–0·4M-potassium chloride

Abstract

A sample of Gigartina skottsbergii has been fractionally extracted. Study of the different fractions, as well as of the carrageenans obtained from them by precipitation with potassium chloride, suggest that the seaweed contains a system of polysaccharides much more complex than that indicated by the classical κ- and λ-picture.

The fraction precipitated at 0·30–0·40M-potassium chloride contained for every ten 3-linked galactose, six 4-linked 3,6-anhydrogalactose and ten sulphate groups (five as 3,6-anhydrogalactose 2-sulphate and five as galactose 2-sulphate).

The possibility of an ‘alternating structure’ is discussed.