Age-dependent changes in esterases of Callosobruchus maculatus Fab. (Bruchidae: Coleoptera)

Age-dependent changes, quantitative as well as qualitative, in esterase activity were found by assaying crude extracts of Callosobruchus maculatus. There is increase in esterase activity in both the sexes with advancing age in bruchids. Esterase from old bruchids showed several additional electrophoretic bands which did not appear in assays of young bruchids; in addition there is an increase in staining intensity of the bands. A rapid increase in esterase activity during the last days of life may be responsible for producing energy used in various metabolic processes in an attempt to escape death.