The characterized moieties analyzed in this paper consists of the amount of β-O-4 linkages, the ratio of syringyl to guaiacyl (S/G) units and the LCC content. β-O-4 linkages are the main reactive centers in native lignin, and the extent to which they are present after the HTT extraction characterizes the degree of lignin transformation. In addition, good correlation between the amounts of β-O-4 linkages and other lignin characteristics have previously been reported for the AqSO process . We note that 2D HSQC NMR analysis also lets us determine the content of several other moieties, the analysis of which has been omitted for brevity in the present work.