title: Atomic force microscopy imaging of carrageenans from red algae of Gigartinaceae and Tichocarpaceae families.
abstract: In the present article, the atomic force microscopy was applied to investigate macromolecular structures of various carrageenan types including hybrid polysaccharides (κ-, κ/β-, κ/ι-, λ-, and X-carrageenans) depending on polysaccharide concentration. The structures dependence on a polysaccharide concentration also was focused. κ-Carrageenan forms both single and two stranded structures at a low concentration. At high concentrations κ-, κ/β-, and κ/ι-carrageenans form fibrous network-like structures by a side-by-side association type at the same time for κ/ι-carrageenan end-to-end association type also was found. Comparably to κ-carrageenan, κ/β-carrageenan network was more open with coarser fibers while κ/ι-carrageenan structure is characterized with a more flexible network. Honeycombed structures due to end-to-end and side-by-side association types were observed for X-carrageenan, while λ-carrageenan formed honeycombed structures only at high concentrations. In order to investigate topographical parameters of the carrageenans macromolecular structure a new method of the autocorrelation function analysis was used for the first time.
authors.affiliation: G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-East Branch of the Russian Academy of Sciences, Prospect 100-let Vladivostoku, 159, Vladivostok 690022, Russia. eka9739@yandex.ru
authors.forename: E V
authors.initials: EV
authors.lastname: Sokolova
authors.forename: E A
authors.initials: EA
authors.lastname: Chusovitin
authors.forename: A O
authors.initials: AO
authors.lastname: Barabanova
authors.forename: S A
authors.initials: SA
authors.lastname: Balagan
authors.forename: N G
authors.initials: NG
authors.lastname: Galkin
authors.forename: I M
authors.initials: IM
authors.lastname: Yermak
mesh_terms: D001704:Biopolymers / Q000737:chemistry; D002351:Carrageenan / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D018625:Microscopy, Atomic Force / Q000379:methods*; D015394:Molecular Structure; D011188:Potassium / Q000737:chemistry; D000461:Rhodophyta / Q000737:chemistry* / Q000145:classification; D012964:Sodium / Q000737:chemistry; D012996:Solutions / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D001704:Biopolymers; D046911:Macromolecular Substances; D012996:Solutions; D014867:Water; D002351:Carrageenan; D012964:Sodium; D011188:Potassium