THE OCCURRENCE OF L-GALACTOSE IN SNAIL GALACTANS

Article abstract of DOI:10.1016/0008-6215(85)90023-0

The occurrence of L-galactose (L-Gal) was investigated in twelve preparations of snail galactans from nine different species.L-Gal (11-15percent) was found not only in members of the family Helicidae, a highly developed group among the Pulmonata, but was detected also in a galactan of the oldest phylogenetic subclass of snails in the Prosobranchiata.To determine the position of the L-Gal residues, the galactans of Arianta arbustorum, Cepaea nemoralis, and Helix pomatia were methylated and hydrolysed, and the partially methylated Gal derivatives were isolated.Each derivative was O-demethylated and the ratio of D- and L-galactose was determined by g.l.c. of the trifluoroacetylated methyl glycosides using a chiral stationary phase.L-Gal (22-34percent) was detected only in the tetra-O-methyl fractions, and hence L-Gal occupies exclusively terminal non-reducing positions.