Stimulation of two step degradation of sodium ascorbate by lignins.

Alkali-lignin stimulated the degradation of sodium ascorbate in phosphate-buffered saline, fetal bovine serum and culture medium, but not in distilled water. ESR spectroscopy revealed that alkali-lignin stimulated ascorbyl radical production even in distilled water. Similar stimulation activity was found in several other plant extracts, commercial and natural lignified materials. These data suggest that the lignin-stimulated degradation process of ascorbate might be separated into two processes, the first being the ascorbyl radical production process and the second the degradation process.