Quantitative Aspects of the Thioacidolysis Method

In Table 6 4 3 are shown the yields of monomeric products recovered from milled wood lignin (MWL) and enzymatically liberated lignin (EL) fractions successively isolated from poplar wood and subjected to various degradation procedures (Lapierre 1986) These values reveal that acidolysis, which should allow the characterization of the same lignin structures as thioacidolysis, 

The low product yield and S/G ratio indicates that these units are not abundant and that they are mainly of the guaiacyl type 

Based on the data in Table 6 4 3, it is apparent that none of the degradation methods currently in use is capable of providing a completely unequivocal characterization of lignin and hence use of a combination of methods is required to attain this objective However, as a single method, thioacidolysis has a definite advantage in that it may be used to characterize unambiguously typical and prominent lignin structures 

Gellerstedt G Lindfors EL (1987) On the formation of enol ether structures in lignin during kraft cooking Nord Pulp Pap Res J 2 71-75 

Node M, Hon H, Fujita E (1976) Demethylation of aliphatic methyl ethers with a thiol and boron trifluonde J Chem Soc Perkin Trans I 2237-2240 Sarkanen KV, Ludwig CH (1971) Definition and nomenclature In Sarkanen KV, Ludwig CH (eds) Lignins Occurrence, formation, structure and reactions Wiley-Interscience, New York, 1-17 

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