Fig. 4. Solution ³¹P nuclear magnetic resonance (NMR) spectra of alkaline extracts of broiler litter extracted with different concentrations of NaOH (0.15, 0.25, and 0.50 M), and a constant concentration of 50 mM EDTA. All spectra are plotted using a line broadening of 0.5 Hz and scaled to the full height of the orthophosphate signal.