Phytochemical investigation of Psiadia Punctulata in Kenya

Abstract

The genus Psiadia belongs to the family Compositae (Asteraceae), which is the largest plant family in the world. It is composed of some 60 species, which is distributed throughout the world. Phytochemical studies have revealed that this genus is characterised by flavonoids (both glycosylated and methylated) and terpenoids (including monoterpene, bufadienolides, cardinolides, diterpenes and triterpenes and/or sterols). Other compounds include phenylpropanoids and tannins. The only species so far reported in Kenya, representing this genus, is P. punctulata (DC) Vatke. Its leaf decoction is reported to be used locally for the treatment of colds and fevers, and for the removal of ectoparasites from cattle. This East African species is considered by some taxonomists to be synonymous to P. arabica Jaub and Spach, a Saudi Arabian species, while others recognise them to be distinct taxa. In this study, the phytochemistry of the surface exudates of P. punctulata has been investigated. Extraction of the surface exudates of the aerial part of this plant was done on fresh plant material. This was carried out by dipping the material into fresh portions of ethylacetate for short periods (15 seconds). The surface exudate was found to be 25% (w/w) of the dry plant material. The wash was then subjected to chromatographic separation, through which twenty-five.compounds were isolated. Of these, fourteen have been characterised by the use of NMR, EIMS, UV and IR spectral data.