Lignins released from Picea abies suspension cultures—true native spruce lignins?

Suspension-cultured cells of Picea abies release lignin in the nutrient medium. Chemical analyses, 1 H and 13 C NMR spectroscopy of this material show that they represent carbohydrate-free guaiacyl type lignins with a high proportion of cinnamyl alcohol side chains a somewhat lower methoxyl content than milled wood lignin from spruce. The molecular weight distribution determined by HPSEC gave a weight average M r of 14 200 and a number average weight close to 4000. These are the first conifer lignin samples to be characterized without chemical or mechanical degradation.