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Several lignin preparations (Freudenberg lignin, Björkman lignin and Pepper lignin), technical lignins (soda, soda-AQ, Kraft, Kraft-AQ and hydrolysis), dimeric lignin model compounds and different polysaccharides (galactoglucomannan, arabinogalactan, xylan and arabinan) were analysed by solid-state 13 C CP/MAS NMR. Signals' assignment in solid-state NMR lignin spectra was performed on the basis ofthe conducted studies and literature data.It wasestablished that there exists strong linear correlation (r = 0.985) between Alkyl-O-Aryl inter-unit bonds' content in lignin and integral signals intensity in NMR spectra in the range of chemical shifts of 96-68 ppm. The integral signals intensity was measured in respect to the reference integral signals in the range of chemicalshifts of 162-102 ppm, which is typical for aromatic carbon atoms.To eliminate the effect from the carbohydrates contained in lignin, the correction factor for calculation was determined, i.e. 0.67% of the area of integration for each percent of carbohydrates. It was shown that the solid-state 13 C CP/MAS NMR method allowed to determine Alkyl-O-Aryl bonds' content in both soluble and insoluble lignin preparations, and also to quantify methoxyl groups' content in soluble preparations.

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