DEGRADATION OF LIGNIN MONOMERS BY THE HINDGUT FLORA OF XYLOPHAGOUS TERMITES

The hindgut flora of the lower termites Mastotermes darwiniensis (Froggatt) and Reticulitermes santonensis (Feytaud) and the higher termite Nasutitermes nigriceps (Haldeman) was tested for its in vivo and in vitro capability to degrade lignin monomers and related aromatic compounds. From the three termites, 53 bacteria were isolated in liquid and on solid media, containing aromatic compounds as carbon source. Most of the tested aromatic compounds were degraded aerobically by mixed and pure cultures. Under fermentative conditions the aromatic compounds were only partially degraded and the aromatic ring was not split. The results suggest that in the anaerobic hindgut the breakdown of aromatic ring systems requires oxygen, which is most probably supplied via the aerated paunch epithelium.