Canolol production from a renewable feedstock via an engineered sinapic acid decarboxylase

This chapter discusses the tasks that were carried out for the bioproduction of canolol (vinyl syringol, VD) from sinapic acid using canola meal as a feedstock. As proof of concept, this monomer was polymerized to produce a new biopolymer with improved properties. Technological advances made in these studies include the development and characterization of a novel enzyme via protein engineering. Guided by the 3-D structure of a phenolic acid decarboxylase (PAD), a sinapic acid decarboxylase (SAD) was evolved to perform the biotransformation of sinapic acid to vinyl syringol under ambient conditions (low temp, pH, pressure). One amino acid substitution at position 85 of the PAD sequence, Ile85Ala, enabled the enzyme to decarboxylate sinapic acid, a substrate that has an extra methoxy substituent at the 5-position on the phenyl ring compared to ferulic acid. Process development studies explored various organic solvents in a biphasic aqueous-solvent reaction for in situ recovery of the product 4-vinyl syringol. In addition, recent advances in the discovery and application of enzyme-based technologies for sinapic acid decarboxylation are discussed.