IR-spectroscopic investigation of aspen wood biolignins

Abstract

Aspen wood biolignins have been investigated by IR spectroscopy and α-, procedure has been developed for determining the amounts of α-, s- and γ-carbonyl groups in the lignins obtained from aspen wood after the action of the lignin-destroying fungusPhanerochaete sanguinea. A large contribution of the Cα-oxidation reaction and the appearance in the biolignins of ester groups and also nonconjugated ketone and aldehyde groups have been revealed. The latter may, presumably, be α-, consequence of the oxidation of the Cγ atoms of the propane chain and the appearance of α-O-4 structural units in the lignin.