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Ruth Falshaw

Publications and source records attributed to Ruth Falshaw.

4 recordsLinked to original sources

Structural analysis of carrageenans from the red alga, Callophyllis hombroniana Mont. Kütz (Kallymeniaceae, Rhodophyta).

The use of a range of modern analytical techniques has facilitated the structural characterisation of the polysaccharide from the New Zealand endemic red alga, Callophyllis hombroniana. The native polysaccharide contains a number of structural units with the largest proportion consisting of 3-linked beta-D-galactopyranosyl 2-sulfate units, alternating with 4-linked 3,6-anhydro-alpha-D-galactopyranosyl 2-sulfate units, that is, theta-carrageenan (36 mol%). C. hombroniana is the first red seaweed reported to naturally contain such a large proportion of theta-carrageenan.

Acetates↗

Enzyme-catalysed synthesis of galactosylated 1D- and 1L-chiro-inositol, 1D-pinitol, myo-inositol and selected derivatives using the beta-galactosidase from the thermophile Thermoanaerobacter sp. strain TP6-B1.

The products from the enzymatic beta-D-galactopyranosylation of 1D-chiro-inositol, 1D-pinitol, 1D-3-O-allyl-4-O-methyl-chiro-inositol, 1D-3,4-di-O-methyl-chiro-inositol, 1L-chiro-inositol and myo-inositol in combined yields ranging from 46% to 64% have been obtained using the beta-galactosidase isolated from an anaerobic extreme thermophile, Thermoanaerobacter sp. strain TP6-B1 and p-nitrophenyl beta-D-galactopyranoside as the donor. Analysis of the products from these reactions reveals information about the acceptor preferences of the enzyme.

Carbohydrate Conformation↗

Analysis of pyruvylated beta-carrageenan by 2D NMR spectroscopy and reductive partial hydrolysis.

A polysaccharide rich in 4',6'-O-(1-carboxyethylidene)-substituted (i.e., pyruvylated) beta-carrageenan has been prepared by solvolytic desulfation of a polysaccharide containing predominantly pyruvylated alpha-carrageenan, which was extracted from the red seaweed, Callophycus tridentifer. The 13C and 1H NMR chemical shifts of pyruvylated beta-carrageenan have been fully assigned using 2D NMR spectroscopic techniques. The 4',6'-O-(1-methoxycarbonylethylidene) group, generated during chemical methylation of the polysaccharide, has been shown to survive under the conditions of acidic hydrolysis that cleave the 3,6-anhydro-alpha-D-galactosidic bonds in permethylated samples of both pyruvylated beta- and pyruvylated alpha-carrageenans. As a result, two novel pyruvylated carrabiitol derivatives have been prepared.

Carrageenan↗