Sulfated galactans carrageenans fractionation

The mixture of galactans from cystocarpic samples of I. undulosa (Cc) were fractionated (Table 2) and treated as depicted in Fig. 4 (Flores, Cerezo, Stortz 2002). Bulk precipitation of Cc with 2M KCl yielded 62 % of an insoluble product (Cl, K/r-carrageenans) and 31% of a soluble one (Cs, p/v-carrageenans). Alkaline treatment of Cl and Cs proceeded with excellent yields (93-95%), giving CIT and CsT in which the precursor units (4-linked a-galactose 6-sulfate and 2,6-disulfate) were cycllzed. Both products were fractionated by precipitation with increasing concentrations of potassium chloride, yielding three fractions insoluble at O.IM, IM, and 2M KCl and one soluble at the latter concentration (Table 3). 

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