Detecting the presence of antitumor terpenoids in bark of white birch from North-eastern Bulgaria

For the first time a chemical analysis of white birch Betula pendula Roth. bark samples from North-eastern Bulgaria region was carried out in order to demonstrate the presence of pentacyclic triterpenoids of ursane, lupane, and oleanane families. A liquid-phase extraction procedure was adapted. The results both from TLS and GC-MS analysis confirmed the presence of two compounds of interest: betulin and I±-amyrin in ratio close to 7:1. Detectable quantity of betulinic acid in the samples was not found.