Extraction, purification and nuclear magnetic resonance (NMR) assignment of garcinoic acid from Garcinia kola (bitter kola) fruit

Continuous extraction of bitter kola nuts, followed by liquid-liquid extraction and flash column chromatography leads to the isolation of garcinoic acid (-tocotrienoloic acid), as the main lipophilic component in a 0.8% yield of the initial dry weight.This compound, an oxidised member of the vitamin E family, was structurally characterised using nuclear magnetic resonance spectroscopy.