Interaction between sodium ascorbate and polyphenols

The interaction between sodium ascorbate and polyphenols was investigated b y two different parameters: radical intensity and cytotoxicity induction. E SR spectroscopy shows that sodium ascorbate, lignins (alkali-lignin, lignin sulfonate, pine cone-derived lignin) and tannins (gallic acid, epigallocat echin gallate (EGCg), tannic acid) all produced radicals with different int ensities under alkaline conditions. All lignin samples significantly enhanc ed the radical intensity and cytotoxic activity of sodium ascorbate, wherea s all tannin samples slightly reduced the radical intensity of sodium ascor bate. Sodium ascorbate efficiently scavenged the radical and cytotoxic acti vity of gallic acid, as expected by the ionization potential and heat of re action by the PM3 semiempirical method. EGCg and tannic acid slightly reduc ed the cytotoxic activity of sodium ascorbate. The present study demonstrat es that lignins and tannins modify the radical intensity and cytotoxic acti vity of sodium ascorbate in different manners, and suggests the applicabili ty of ESR spectroscopy for the screening of drug to drug interaction.