Regioselectivity of Ferulic Acid Polymerization Catalyzed by Oxidases

Yu. N. Kupriyanovich^1 #, S. A. Medvedeva¹, A. V. Rokhin² and L. V. Kanitskaya¹

^#Phone: (395-2) 426-911; e-mail: jkupr@irk.ru

¹ Irkutsk Institute of Chemistry, Siberian Division, Russian Academy of Sciences, ul. Favorskogo 1, Irkutsk, 664033, Russia;
² Irkutsk State University, ul. Lermontova 126, Irkutsk, 664033, Russia

Received: July 11, 2006;  in final form: September 13, 2006

Abstract.  Enzymatic oxidation of ferulic acid catalyzed by oxidases (laccase and peroxidase) was carried out. Ferulic acid was shown to be subjected to oxidative processes leading to the formation of oligomeric and polymeric structures. The polymer formation takes place due to the formation of C_Ar-C_Ar- and C_Ar-O-C_Ar-bonds, as well as due to reactions of opening of the propane chain double bond. Different dynamic conditions of the enzymatic reactions were used to study the effects of conditions on the biosynthesis in vitro of some dehydropolymers: the method of dropwise mixing (endwise polymers) and a single addition (bulk polymers). The chemical structures of the resulting compounds were examined by the methods of IR, ¹H NMR, and ¹³C NMR spectroscopy. Differences in the quantitative ratio of structural fragments in a polymer cause changes in its thermal characteristics.

Key words:  enzymatic oxidation;- ferulic acid; laccase; peroxidase

Russian Journal of Bioorganic Chemistry 2007, 33(5): 516-522