Antimutagenic Acitivity against Trp-P-1 of the Edible Thai Plant,Oroxylum indicum Vent.

A methanolic extract of Oroxylum indicum strongly inhibited the mutagenicity of Trp-P-1 in an Ames test. The major antimutagenic constituent was identified as baicalein with an IC₅₀ value of 2.78±0.15 μM. The potent antimutagenicity of the extract was correlated with the high content (3.95±0.43%, dry weight) of baicalein. Baicalein acted as a desmutagen since it inhibited the N-hydroxylation of Trp-P-2.