Galactan

Galactan (galactosan) is a polysaccharide consisting of polymerized galactose.^[1] In general, galactans in natural sources contain a core of galactose units connected by α(1→3) or α(1→6), with structures containing other monosaccharides as side-chains.^[2]

Galactan

Names
Other names D-Galactan; Galactosan
Identifiers
CAS Number	9037-55-2
ChEBI	CHEBI:37165
KEGG	C05796
Properties
Chemical formula	(C6H10O5)n
Molar mass	Variable
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Galactan derived from Anogeissus latifolia is primarily α(1→6), but galactan from acacia trees is primarily α(1→3).^[3]

Halymenia durvillei is a red seaweed (algae) that produces a sulfated galactan.^[4] Several other algae species also contain galactans.^[5] Including Carpopeltis F.Schmitz, 1895.^[6]

Galactan is found in the side chains of rhamnogalacturonan I (RG-I) and is needed for gel formation in the cell walls of organisms.^[7] It was observed there was less of the gelling characteristic (as well as the polymeric chains being more likely to degrade) when fewer galactans were present in the polymeric side chains. ^[7][8]

See also

• Agar
• Galactooligosaccharide