The bark of Saraka asoca (asoka) is commonly used to treat various dis
eases by the Indian system of medicine and in Sri Lanka. Further purif
ication and chemical analysis of the active compound from the bark ext
ract of asoka showed that (-)-epicatechin was responsible for the obse
rved antitumour/anticarcinogenic activity. Papilloma formation in mice
initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted usi
ng croton oil was inhibited by the topical application of 100 mg/kg bo
dy weight (b.w.) of (-)-epicatechin isolated from asoka bark extract.
Oral administration of the same dose restricted the growth of s.c. inj
ected 20 methylcholanthrene (MCA) induced soil tissue fibrosarcomas si
gnificantly in mice. Elevations of almost 2-4-fold in the intracellula
r reduced glutathione and related enzymes viz., glutathione reductase
and glutathione S-transferase of sarcoma-180 tumour cells were noted i
n the presence of 1 mug/ml of (-)-epicatechin, further highlighting it
s antiproliferative effect.