coniferin

Coniferin is the glucoside of coniferyl alcohol, a monolignol that serves as a building block in lignin. It is found mainly in gymnosperms, particularly conifers, where it acts as a soluble storage and transport form of coniferyl alcohol. In plants, coniferin is produced by the attachment of glucose to coniferyl alcohol through a β-D-glucosidic bond, typically catalyzed by UDP-glucosyltransferases. The molecule can be hydrolyzed by β-glucosidases or under acidic conditions to release coniferyl alcohol and glucose.

The liberated coniferyl alcohol is a precursor for lignin biosynthesis. It can be oxidized by peroxidases or laccases and subsequently incorporated into lignin polymers, or diverted into other phenylpropanoid pathways. Coniferin thus functions as a reservoir that helps regulate the supply of monolignols during wood formation, wound response, and other developmental processes.

Glycosylation of coniferyl alcohol to form coniferin increases its solubility and reduces potential autotoxicity, enabling storage in the cytosol or vacuoles and mobilization when lignification or defense needs arise. In analytical studies, coniferin is often used as a model compound for understanding monolignol transport, storage, and the regulation of lignin biosynthesis. Related monolignol glycosides are found in various plant groups, reflecting a common strategy to manage lignin precursors.