HIGH-PERFORMANCE SIZE-EXCLUSION CHROMATOGRAPHIC CHARACTERIZATION OF WATER-SOLUBLE POLYMERIC SUBSTANCES PRODUCED BY PHANEROCHAETE-CHRYSOSPORIUM FROM FREE AND WHEAT CELL-WALL BOUND 3,4-DICHLOROANILINE

A high-performance size-exclusion chromatographic (HPSEC) method was d eveloped and optimized for the separation of aq, soluble polymeric xen obiotics. The use of this method for the characterization of aq. solub le polymeric substances produced by Phanerochaete chrysosporium cultur es from [ring-(UC)-C-14]-3,4-dichloroaniline ([C-14]DCA) and wheat cel l wall bound [ring-U-C-14]-3,4-dichloroaniline was demonstrated by on- line UV detection at 280 nm and radioactivity tracing. The polymeric n ature of aq, soluble lignin-like C-14-products was shown by polydisper sity and correspondence of the UV signal at 280 nm with the radioactiv ity trace. The higher polydispersity and molecular mass of lignin-like substances in low-C cultures as compared to those in low-N cultures w ere found to be associated with lower mineralization rates. Results in dicated that the major portion of copolymerized DCA was apparently cov alently bound via labile bonds to the alpha-C atom of the lignin monom er side chains on native wheat cell wall.