Review: Biocatalytic transformations of ferulic acid: An abundant aromatic natural product

Abstract

In this review we examine the fascinating array of microbial and enzymatic transformations of ferulic acid. Ferulic acid is an extremely abundant, preformed phenolic aromatic chemical found widely in nature. Ferulic acid is viewed as a commodity scale, renewable chemical feedstock for biocatalytic conversion to other useful aromatic chemicals. Most attention is focused on bioconversions of ferulic acid itself. Topics covered include cinnamoyl side-chain cleavage; nonoxidative decarboxylation; mechanistic details of styrene formation; purification and characterization of ferulic acid decarboxylase; conversion of ferulic acid to vanillin; O-demethylation; and reduction reactions. Biotransformations of vinylguaiacol are discussed, and selected biotransformations of vanillic acid including oxidative and nonoxidative decarboxylation are surveyed. Finally, enzymatic oxidative dimerization and polymerization reactions are reviewed.

Bioproduction of lauryl lactone and 4-vinyl guaiacol as value-added chemicals in two-phase biotransformation systems

“…Decarboxylation of FA to VG is a potentially profitable value addition to the starting material especially if the FA can be extracted efficiently from its bound polysaccharides in the biomass (Rosazza et al 1995). VG is priced some 40 times more than FA, and it can be biotransformed further to acetovanillone, ethylguaiacol, and vanillin (Rosazza et al 1995;Mathew and Abraham 2006).…”

“…VG is priced some 40 times more than FA, and it can be biotransformed further to acetovanillone, ethylguaiacol, and vanillin (Rosazza et al 1995;Mathew and Abraham 2006). As a styrene-type molecule, VG can be polymerized; the resultant oligomer [poly(3-methoxy-4-hydroxystyrene)] was found to be easily biodegradable (Hatakeyama et al 1977).…”

“…Interestingly, the Fdc or Pad is a relatively conserved group of proteins (60% identity); most of the amino acid substitutions that may be responsible for substrate specificity are located in the C-termini. The Fdc from B. pumilus UI-670 has been shown to decarboxylate p-coumaric acid (4-hydroxycinnamic acid) but not 2-or 3-hydroxycinnamic acid indicating that a 4-hydroxyl group is essential for the decarboxylation reaction (Rosazza et al 1995).…”

“…Several bacteria and fungi have been shown to be able to convert FA to VG via decarboxylation by a ferulic acid decarboxylase (Fdc) also known as phenolic acid decarboxylase (Huang et al 1993(Huang et al , 1994Rosazza et al 1995;Cavin et al 1998;Barthelmebs et al 2001;Tsujiyama and Ueno 2008). Several of the Fdc or Pad-encoding genes from organisms, e.g., Lactobacillus plantarum, Pediococcus pentosaceus, Bacillus sp.…”

“…BP-7, B. subtilis,andB. pumilus strain PS231 and ATCC 14884, have been cloned and sequenced (Zago et al 1995;Cavin et al 1997Cavin et al , 1998Barthelmebs et al 2001;P r i me ta l .2003) The first purified Fdc, coming from the Bacillus pumilus (formerly identified as Pseudomonas fluorescens) strain UI-670, was characterized to be a homodimeric 20.4-kDa subunit protein, and it appeared to be produced constitutively (Huang et al 1993(Huang et al , 1994Rosazza et al 1995). As part of this study, the fdc gene from B. pumilus UI-670 was cloned in E. coli for its use in biotransformation experiments for the recovery of VG from FA in the TPPB system.…”