Open AccessIdentification of 4,6‐O‐(1‐carboxyyethylidine)‐ d ‐galactose in extracellular polysaccharide from Palmella texensis UTEX 1708
Author(s) -
Ha Youn W.,
Thomas Ron L.
Publication year - 1991
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1991.tb04415.x
Subject(s) - galactose , galactan , chemistry , polysaccharide , residue (chemistry) , nuclear magnetic resonance spectroscopy , trimethylsilyl , biochemistry , stereochemistry , chromatography , organic chemistry
Summary Extracellular polysaccharide (EPS) from Palmella texensis UTEX 1708 contained galactose as a sole sugar constituent. 1 H‐NMR spectroscopy indicated the possibility of the presence of pyruvyl groups. Pyruvyl groups were also supported by the positive result of coloremetric assay. Methylation analysis before and after depyruvylation showed that a 2,3‐linked galactose was pyruvylated at the 4,6‐positions. Studies of trimethylsilyl (TMS) derivatives of methylglycosides on gas chromatography (GC) supported the 4,6‐position and the resulting fragmentation pattern on GC‐mass spectroscopy confirmed the presence of the pyruvic acetal, 4,6‐O‐(1‐carboxyethylidine)‐ d ‐galactose residue. The occurence of either galactan or pyruvylated galactose in green algae has not yet been reported.