Controlling the polymerization of coniferyl alcohol with cyclodextrins

Abstract : The mono-electronic oxidation of coniferyl alcohol leads to phenoxy radicals and ultimately to the synthesis of dimeric lignans. Coniferyl alcohol and lignans are all potential guests for cyclodextrins (CDs) to form noncovalent host-guest inclusion complexes. Here, the influence of CDs with different cavity volumes (i.e. α, β or γCD) on the laccase-driven oxidation of coniferyl alcohol is studied. We are clearly showing that βCD interacts with the lignan products and selectively prevent their further oxidation by the enzyme. Moreover, amongst the three lignans generated the system made of a laccase and βCD allows a selective enrichment of pinoresinol, a behaviour somehow mimicking that of plant dirigent proteins.