Seasonal dynamics of polysaccharides in Norway spruce (Picea abies).

Annual dynamics of accumulation and changes in the monosaccharide composition of pectin-, arabinan- and galactan-containing polysaccharides and binding glycans isolated from greenery (thin branches with needles) of Norway spruce were investigated in this study. The polysaccharides were compared with polysaccharides of Siberian fir according to the yields, composition and content of typical components. It was shown that Norway spruce greenery contains lowly methyl-esterified pectin extracted with ammonium oxalate, which is a part of protopectic complex and is bound with components of cell walls via ionic bonds. In contrast, Siberian fir greenery contains mainly water-extracted highly methyl-esterified pectin, weakly bound to cell wall components. It was concluded that an autumn-winter period is the optimal time for harvesting Norway spruce and Siberian fir greenery for isolation of the pectic polysaccharides. The revealed regularities indicate that there is a certain biorhythm of accumulation of the compounds, probably determined by genetic factors.