[To the classification of commercial Calamus drugs]

Acorus calamus L. yields different races depending upon the number of chromosomes in the plant cells and consequently different drug types with varying content of beta-asarone. The phenylpropane derivative proved to be carcinogenic in several animal tests. The diploid drug does not contain traceable amounts of beta-asarone, the triploid variety contains 0.3 per cent in the rhicome, the tetraploid yielded two races with a) 2 per cent and b) between 4 and 8 per cent beta-asarone. For reasons of optimal drug safety the use of asarone-rich races should be avoided. They can be distinguished by a fast and safe method of determining the extinction of the drug extract at the beta-asarone maxima of 253 and 303 nm. The determination of beta-asarone is possible using quantitative direct evaluation of thin-layer chromatograms on alumina layers with an efficient separation of the asarone. A good selectivity, obtainable at 300 nm, allows determination of beta-asarone down to 0.1 microg in drug extracts.