Surface compounds of psiadia punctulata

Abstract

The genus Psiadia (Compositae) is represented by 60 species and is found south of Tropical Africa, Madagascar and Tropical Asia (1). Very limited phytochemical information is available in this genus. However, this has revealed diverse group of compounds with remarkable biological activities including anti-tumor, cytotoxic (3), hemotoxic, neuromuscular blocking (4), anti-helmintic and anti-inflammatory (2). As such the genus has been of great value in traditional medicine. Psiadia punctulata (DC) Vatke leaves whose decoctions are used in East Africa for relief of abdominal pains, exhibits aerial surface deposition up to 25% w/w of dry material. Our current work is focused on the study of the surface compounds of this plant. This investigation has so far revealed three different kinds of compounds which include flavones with methoxylation on . either A- or B-ring or both (e.g. Compound 1), diterpenoids (both trachyloban and kaurane types e:g. compounds 2 and 3 respectively) and long chain cynnamoyl esters e.g. compound 4. The Middle Eastern P arabica with which P punctulata is confused has about fourteen different flavones and flavonols along with kaulane but no trachyloban diterpenes which confirms the distinction between the two. In this presentation the results of our findings will be discussed.