Author(s):
Azevedo, G. ; Torres, M. D. ; Almeida, P. L. ; Hilliou, L.
Date: 2022
Persistent ID: https://hdl.handle.net/1822/81652
Origin: RepositóriUM - Universidade do Minho
Subject(s): Ahnfeltiopsis devoniensis; Chondrus crispus; Mastocarpus stellatus; Hybrid carrageenan; Rheology
Description
The types and amounts of carrageenans present in a set of Mastocarpus stellatus, Chondrus crispus and Ahnfeltiopsis devoniensis, are assessed by solid-state NMR performed directly on dried and powdered seaweeds. The resulting chemical analysis is compared with the chemical structure and gel elasticity of the hybrid carrageenans extracted from these three carrageenophytes. ν-carrageenan is only found in a single sample of M. stellatus, whereas C. crispus and A. devoniensis essentially contain ι- and μ-carrageenans. A significant amount of κ-carrageenan is found in all samples of M. stellatus, whereas this type of carrageenan was found in a single sample of A. devoniensis. Hybrid carrageenans (HK) made of κ-, ι-, μ- and ν-carrageenan units were found in all hot extracts from the seaweeds, and their respective contents are in line with earlier reports on the HK extracted from these seaweeds. No correlations between the carrageenan contents in eight seaweeds and the chemical structures of their corresponding extracted HK can be found. However, a positive nonlinear correlation between the intrinsic viscosity of extracted HK and their gel elastic modulus is found in a set of 8 carrageenophytes.