Chemotaxonomic significance of the c-glycosylflavonoid (Vitexin) in pereskia bleo kunth. (cactaceae)

Abstract

Pereskia bleo (Family; Cactaceae) is a medicinal plant traditionally used by the local people in Malaysia to treat cancer, high-blood pressure, diabetes, rheumatism and inflammation. Generally, the plant leaves are consumed raw or brewed to be taken as decoction. The medicinal effects exhibited by the plant are mainly attributed to various chemical compounds, which can be classified using various approaches such as chemotaxonomy. Besides, the chemotaxonomic approach is also one of the useful methods in the field of plant taxonomy. The aim of this study is to reveal the presence of the C-glycosylflavonoids (vitexin) in one of the Cactaceae family member which can be useful to justify its similarities with the Didieraceae family. Isolation and purification of P. bleo extracts was conducted using various chromatographic techniques and the compounds were identified mainly through the Nuclear Magnetic Resonance (NMR) analysis particularly. Phytochemical evaluation of P. bleo has shown the presence of β-sitosterol (1), β-sitosterol glucoside (2) and vitexin (3) in the hexane, dichloromethane and ethyl acetate extracts, respectively. The isolation of β-sitosterol glucoside and vitexin, a C-glycosylflavonoid compound named vitexin, is described for the first time in this species. The occurrence of the C-glycosylflavonoids in Cactaceae is of chemotaxonomic importance, showing that Cactaceae (particularly the Pereskiaeae sub-family) and Didieraceae family are similar not only morphologically, but also chemotaxonomically, which contrasts to the previous report.