BIODEGRADATION OF SOLUBLE REDOX POLYMERS .2. (0.017FERROCENE)AMYLOSE AT A ROTATING-DISK ELECTRODE

The behavior of (ferrocene)amylose (FA), in the presence of amylolytic depolymerases (or-amylase from Aspergillus orycae and human saliva), has been investigated by cyclic voltammetry at a rotating disk electro de (CVA/RDE). Growth of the limiting current with time in the presence of the enzymes is proportional to the amount of enzyme introduced, Th e quantitative data treatment to assay the endoamylolytic activity of enzymes at CVA/RDE involves plotting (i(dt)/i(d0))(4,5) against time; the slope of the linear plot being equal to (rate) M(n0)c(-1), a here i(dt) and i(d0) are the limiting currents at time t and 0, respectivel y, (rate) is the enzymatic activity, M-n0 is the number averaged molec ular weight of FA at t = 0, and c is its concentration The comparison of CVA/RDE with the 3,5-dinitrosalitylic acid and the Somogyi-Nelson r educing saccharides procedures shows advantages of the former, especia lly in assaying small quantities of enzymes. Also the CVA/RDE approach is simpler and takes place under much milder conditions, The main dis advantage of CVA/RDE is the inhibiting effect of Triton X-100 in the r eaction between FA and the amylases which is not observed in the case of native, ferrocene-free amylose. In general, CVA/RDE appears to be a n attractive analytical method for monitoring diverse enzymatic depoly merization reactions.