RECOVERY OF PHENOLIC COMPOUNDS FROM EXUVIAE OF THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

Abstract

A number of ketocatechols have been isolated and identified from acid hydrolysates of larval and pupal exuviae of the spruce budworm, Choristoneura fumiferana. The most abundant of these, 2-hydroxy-3′,4′-dihydroxyacetophenone, represented 5.8% of the dry weight of pupal exuviae, 4.6% of larval head capsules, and 0.3% of the remaining larval exuvium. This compound is thought to be the primary breakdown product arising from crosslinks between cuticular proteins and the aliphatic sidechain of a phenolic tanning compound. The yields therefore reflect the extent of β-sclerotization, one of two mechanisms proposed for the hardening of insect cuticle. Budworm is similar to other species with respect to the types of hydrolysis products recovered although three previously undescribed compounds were detected.