Monolignol

See also: Hydroxycinnamic acids / Phenylpropanoids

Monolignols are aromatic alcohols that are used to create lignin and lignans. They are made up of:

• Paracoumaryl alcohol (H)
• Coniferyl alcohol (G)
• Sinapyl alcohol (S)

Monolignols are polymerized during biosynthesis to form a complex, three-dimensional structure. These units are linked by various bonds, including:

• β–O–4
• 5–5
• β–5
• 4–O–5
• β–1
• dibenzodioxocin
• β–β

Lignin is a complex product of monolignols. It is an integral part of the secondary cell walls of plants and some algae. Lignin is particularly important in the formation of cell walls, especially in wood and bark, because it lends rigidity and does not rot easily. It has many biological functions such as:

• Water transport
• Mechanical support
• Resistance to various stresses

Lignin is generally obtained from wood and is a by-product of the paper and pulp industry.