Effect of glycyrrhizic acid on lappaconitine phototransformation.

1H NMR and CIDNP methods were used to demonstrate that triterpene glycoside (glycyrrhizic acid, GA) can substantially change the efficiency and direction of phototransformation of alkaloid lappaconitine (LA) due to both its solubilization in GA micelles and protonation of LA amine nitrogen in water-alcohol solutions. The LA solubilization in the GA micelle suppresses the process of deacylation.