%0 Journal Article
%T Quantification of (1¡ú4)-¦Â-d-Galactans in Compression Wood Using an Immuno-Dot Assay
%A Ramesh R. Chavan
%A Leona M. Fahey
%A Philip J. Harris
%J Plants
%P 29-43
%D 2015
%I MDPI AG
%R 10.3390/plants4010029
%X Compression wood is a type of reaction wood formed on the underside of softwood stems when they are tilted from the vertical and on the underside of branches. Its quantification is still a matter of some scientific debate. We developed a new technique that has the potential to do this based on the higher proportions of (1¡ú4)-¦Â-d-galactans that occur in tracheid cell walls of compression wood. Wood was milled, partially delignified, and the non-cellulosic polysaccharides, including the (1¡ú4)-¦Â-d-galactans, extracted with 6 M sodium hydroxide. After neutralizing, the solution was serially diluted, and the (1¡ú4)-¦Â-d-galactans determined by an immuno-dot assay using the monoclonal antibody LM5, which specifically recognizes this polysaccharide. Spots were quantified using a dilution series of a commercially available (1¡ú4)-¦Â-d-galactan from lupin seeds. Using this method, compression and opposite woods from radiata pine ( Pinus radiata) were easily distinguished based on the amounts of (1¡ú4)-¦Â-d-galactans extracted. The non-cellulosic polysaccharides in the milled wood samples were also hydrolysed using 2 M trifluoroacetic acid followed by the separation and quantification of the released neutral monosaccharides by high performance anion exchange chromatography. This confirmed that the compression woods contained higher proportions of galactose-containing polysaccharides than the opposite woods.
%K Pinus radiata
%K coniferous gymnosperms
%K compression wood
%K (1¡ú4)-¦Â-d-galactans
%K immuno-dot assay
%K LM5 monoclonal antibody
%K monosaccharide composition
%K delignification
%U http://www.mdpi.com/2223-7747/4/1/29