What’s good in the wood: unveiling chemical shifts induced by Cryptotermes brevis digestion

Abstract

The West Indian drywood termite, Cryptotermes brevis , causes large economic impacts by consuming wooden structures. The complexity of the lignocellulosic matrix presents many challenges to termites, who have evolved methods to tolerate recalcitrant components. Chemical variations among wood species and the ability of C. brevis to consume them remains understudied. This work compared the chemical composition of hoop pine ( Araucaria cunninghamii ) and shining gum ( Eucalyptus nitens ) before (whole wood) and after ingestion (frass) by C. brevis . Holocellulose content in hoop pine declined from 58.7 % of the original wood to 10.9 % in frass, while shining gum holocellulose content decreased from 55.7 % to 12.5 % in the frass. Reductions in hemicellulose were 62 % and 38 %, respectively, while >90 % reductions in α-cellulose were observed within either wood source. Klason lignin levels were similar in wood and frass for both diets. The total extractives did not differ between wood and frass, but specific compounds varied independently. The results suggest the C. brevis gut and/or its microbiome primarily utilised carbohydrate components while essentially disregarding lignin and extractives. The results improve the understanding of how wood sources affect termite activity and may advise future material choices for improved pest management.