Iridoid glucosides - chemotaxonomic markers in Loasoideae

As part of a chemotaxonomic screening for iridoids in Loasaceae samples fro m 74 species, mainly from subfamily Loasoideae, were assayed using HPLC and TLC. The presence of the iridoid dimer tricoloroside methyl ester and othe r oligomeric iridoids consisting of loganin and secoxyloganin moieties turn ed out to be characteristic for members of ser. Macrospermae and ser. Flori bundae of the genus Loasa. In species of the genus Caiophora 10-hydroxyoleo side dimethyl ester and a further not yet identified iridoid serve as chemo taxonomic markers. Other monomeric iridoids (loganin, loganic acid, secoxyl oganin, secoxyloganin methyl ester, sweroside, 8-epi-kingiside) are widespr ead throughout the whole family without having systematic value at subfamil y or generic level. (C) 1999 Elsevier Science Ltd. All rights reserved.