The flavonoids of the genus Lathyrus and a comparison of flavonoid patterns within the tribe vicieae

Abstract

A leaf survey of Lathyrus showed that the flavonols kaempferol and quercetin were present in 36 of 38 species representing nine sections of the genus. Six glycosides of each flavonol were characterised. Kaempferol 3-sophoroside-7-glucoside, previously reported in L. vernus, was found in four further species. Other distinctive glycosidic patterns in the genus include the 3-robinobioside, the 3-sophoroside and the 3-lathyroside-7-rhamnoside. The two species surveyed in section Pratensis were different from all the others, in having flavones as well as flavonols and, additionally, in having proanthocyanidins. These differences in leaf flavonoid patterns also extended to the flowers, pods and seeds. Isoflavone accumulation was confirmed in L. montanus but otherwise the genus was depauperate in isoflavones. A comparison of patterns found in Lathyrus with those of Cicer, Lens, Pisum and Vicia indicate that each genus has a distinctive flavonoid profile.