Methods for detecting and determining levels of monolignol ester conjugates incorporated into lignin and compounds relating thereto

A method of detecting and, optionally, determining a level of incorporation of monolignol ester conjugates into lignin, the method comprising:

• (a) derivatizing lignin to acylate at least a portion of free phenolic and aliphatic hydroxyls and to halogenate at least a portion of benzylic alcohols present in the lignin, to yield derivatized lignin;
• (b) treating the derivatized lignin of step (a) with a reducing agent to cleave at least a portion of the derivatized lignin, to yield lignin cleavage products;
• (c) acetylating at least a portion of free hydroxyl groups in the lignin cleavage products of step (b) with a labeled acetylation agent, to yield labeled lignin fragments, wherein the labeled acetylation agent is labeled acetic anhydride, wherein the labeled acetic anhydride is labeled with an isotope;
• and
• (d) detecting the labeled lignin fragments produced in step (c).