FIGURE 4.

In vitro polymerization of monolignols. A, LC-MS profiling of the reaction of coniferyl alcohol incubated with horseradish peroxidase and H₂O₂ (solid line), or with buffer alone as the control (dashed line). The profile shows a predominant dimer G(8–5)G and the minor products of G(8-O-4)G and G(8–8)G. The inset shows atmospheric pressure chemical ionization mass spectrum of the former. The mass and UV spectra for the other products are shown in supplemental Fig. S6. B, LC-MS profiling of the reaction of methoxyconiferyl alcohol incubated with horseradish peroxidase and H₂O₂ (solid line), or with buffer alone as the control (dashed line). No dimers/oligomers were detected.