Total yields on lignin basis are in the range 29–33% for in situ
lignins, which is lower value than the yield found for E. globulus
wood (38%) but similar to that obtained for other hardwoods
and annual plants (Nishimura et al., 2002). However, for giant
reed lignin, other authors (Seca et al., 2000) have found higher
yield by NO (about 40%). Mimosa and willow present the typical
ratios H:G:S for hardwood lignins, with predominance of syringyl
moieties (S/G 1.8–1.6) and low content of H – Table 2. Gramineae
plants usually present higher content of H units and predominance
of G over S units.