A COMPUTATIONAL STRATEGY FOR THE DECONVOLUTION OF NMR-SPECTRA WITH MULTIPLET STRUCTURES AND CONSTRAINTS - ANALYSIS OF OVERLAPPING C-13-H-2 MULTIPLETS OF C-13 ENRICHED METABOLITES FROM CELL-SUSPENSIONS INCUBATED IN DEUTERATED MEDIA

A computational strategy for the deconvolution of complex spectra invo lving scalar multiplet patterns is presented, This approach fits spect ra that can be composed of single resonances as well as scalar couplin g multiplets for which resonance frequencies, intensities, and linesha pe parameters can be optimized, For multiplets, the coupling constant also is optimized, Any external information about the optimizable para meters can be taken into account as external constraints, A lineshape described by absorptive and dispersive Lorentzian and Gaussian contrib utions and the baseline with up to 40 Fourier and polynomial terms can likewise be optimized, The effectiveness of the procedure is assessed on the basis of computer simulated deconvolutions of a composite of ( 1)J(C-13-H-2) multiplets arising from a mixture of all possible C-13-H -2 isotopomers of deuterated L-[3-C-13]lactate generated from cell pre parations incubated with D-[1-C-13]glucose in D2O, which was analyzed previously with a manual deconvolution procedure (R. Willem, M. Biesem ans, F. Kayser, W. J. Malaisse, Magn. Reson. Med. 31, 259-267 (1994)), The use of constraints is shown to lead to an improvement in the resu lts. The fitting strategies and the importance of the baseline as an o rigin of bias are discussed.