Influence of tissue source and growth rates on dry weight and carrageenan composition of Chondrus crispus (Gigartinales, Rhodophyta)

Abstract

Carrageenan analyses were conducted on vegetative female clones of Chondrus crispus that were cultured to provide tissues with differing growth rates . Tissue dry weights increased from apex to base of fronds . Total carrageenan contents were lower in apical 1 to 2 cm segments than elsewhere in the frond, except when the alga was grown at high photon irradiances . Clone 373A contained more carrageenan than clone G8. The proportion of 0 .3 M KCl-soluble polymers in the total native carrageenans varied from 44 to 92%, being highest in older tissues of fronds cultured at high photon irradiances . The apical 1 cm segments contained less KCI-soluble carrageenans than other tissues from the corresponding fronds . The KCl-soluble carrageenans, when alkali-modified and refractionated, afforded the expected kappa-iota carrageenan in > 79% yields . The remainder consisted of a polymer containing 23 .1 % SO 3Na and 8 .4% 3,6-anhydrogalactose . Lambda carrageenan was not detected . Variations in carrageenan distribution between the apical region and other parts of the frond may reflect the increasing influence of medullary tissue developed as the immature cells differentiate .

Marine algae sulfated polysaccharides for tissue engineering and drug delivery approaches

“…Carrageenans are sulfated polysaccharides that occur as matrix material in several species of red seaweeds (Rhodophyceae), with main sources being Chondrus crispus , Gigartina , Eucheuma cottonii and spinosum , and that can be extracted with water or aqueous alkali methods 35 - 37 . Chemically, these hydrophilic colloids are highly sulfated galactans, with sulfate content varying between 15% and 40%, 38 with a primary structure based on an alternating sequence of β (1–4) and α (1–3) linked D-galactose residues, 39 resulting in polymers with molecular weight ranging from 10 5 to 10 6 Da 40 , 41 .…”