Laccase-mediator catalyzed conversion of model lignin compounds

Laccases play an important role in the biological break down of lignin and have great potential in the deconstruction of lignocellulosic feedstocks. We examined a variety of laccases, both commercially prepared and crude extracts, for their ability to oxidize three model lignol compounds (p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol). We identified both mediated and non-mediated laccasecatalyzed reactions that converted p-coumaryl alcohol and sinapyl alcohol to p-hydroxybenzaldehyde and 2,6-dimethoxybenzoquinone, respectively. Interestingly, the products produced by the concerted action of the laccase mediator system on lignol substrates are the same as those produced by chemical catalytic approaches. The enzymatic approach affords the opportunity for a biological approach to the conversion of lignin to valuable specialty chemicals that have use in a variety of industrial, consumer and pharmaceutical applications. Published by Elsevier Ltd.