Structures of cell-wall polysaccharides from suspension-cultured cells of Cryptomeria japonica

Cell walls isolated from suspension-cultured cells of Cryptomeria japonica D. Don (sugi) were treated by sequential extraction with trans-1,2-cyclohexanediamine-N,N,N',N'-t acid (CDTA), Na2CO3,1 M and 4 M KOH solutions to isolate cell-wall polysaccharides. Most parts of the pectin were solubilized with 0.05 M CDTA and Na2CO3 solutions, and total yields of these fractions amounted to about 20% of the cell walls. These fractions consisted of homogalacturonan and rhamnogalacturonan. Hemicellulosic polysaccharides extracted with 1 M and 4 M KOH solutiuons were comprised mainly of glucomannan and xyloglucan. The main component of the extract residue was cellulose. Pectin and hemicellulose still remained in the residue. The cell-wall polysaccharides of suspension-cultured sugi cells consisted of 23.7% pectic polysaccharides, 17.9% xyloglucan, and 10.2% glucomannan. The other components were traces of xylan and cellulose. The polysaccharide composition of the suspension-cultured sugi was similar to that of the xylem differentiating zone of sugi. Futhermore, except for the presence of glucomannan, suspension-cultured sugi (gymnosperm) had the same cell-wall polysaccharides as those of suspension-cultured sycamore maple (Acer pseudoplatanus L.; angiosperm) cells.