The distribution of isoflavonoids in Cicer

Fifteen annual and perennial species of Cicer have been analysed for the presence of isoflavonoids. The pterocarpans medicarpin and maackiain and the isoflavonoids biochanin A and formononetin were present in the roots of all species and also occurred widely as glucosides or malonylated glucosides. Five recently identified isoflav-3-enes and a 2-arylbenzofuran were detected exclusively in three species, C. bijugum, C. judaicum and C. pinnatifidum, and their occurrence was restricted to the roots. Conversely, 9-O-methylcoumestrol was recorded in all species except for C. bijugum, C. judaicum and C. pinnatifidum. These species have been placed previously in series Cicer, a taxonomic grouping of 6 species within section Cicer of subgenus Cicer. The present results indicate that they should be considered as taxonomically distinct from other species in this series, a proposal supported by a number of other recent studies. (C) 1998 Elsevier Science Ltd. All rights reserved.