ANTIMUTAGENIC AND ANTICARCINOGENIC ACTIVITY OF NATURAL AND SYNTHETIC CURCUMINOIDS

Five synthetic curcuminoids and three natural curcuminoids were invest igated for their antimutagenic and anti-promotional activity. The natu ral curcuminoids, curcumin I (diferuloylmethane), curcumin II (feruloy l-p-hydroxycinnamoylmethane) and curcumin III (bis-(p-hydroxycinnamoyl )methane) isolated from Curcuma longa were found to be potent inhibito rs of mutagenesis and crotean oil-induced tumour promotion. Curcumin I II produced 87.6% inhibition to 2-acetamidofluorene (2-AAF) induced mu tagenesis, at a concentration of 100 mu g/plate, curcumin II and curcu min I produced 70.5% and 68.3% inhibition at the same concentration. A ll the synthetic curcuminoids were found to inhibit 2-AAF-induced muta genicity among which salicyl- and anisylcurcuminoids were the most act ive. Curcumin III was the most effective anti-promotor among natural c urcuminoids. While 90% of the control animals were having papillomas o n the 10th week of tumour initiation, only 10% of the curcumin III-tre ated animals, 20% of the curcumin II-treated animals, and 40% of the c urcumin I-treated animals were having papillomas. salicylcurcuminoid, which was causing no papillomas by the 10th week, was the most potent anti-carcinogen among the synthetic curcuminoids. Piperonal curcuminoi d also exhibited anti-promotional activity.