Phytochemical Constituents of Some Medicinal Plants in South West, Nigeria

The present study was undertaken to investigate the phytochemical constituents of leaves of four medicinal plants viz: Annona senegalensis, Axonopus compressus, Bryophyllum pinnatum and Heliotropium indicum, which are traditionally used as medicine in southwestern part of Nigeria. Qualitative analysis carried out on each plant leaves shows that alkaloids, phenolics, flavonoids, saponins, tannins, were present in all the plants. These plants leaves were also subjected to quantitative analysis and the results indicated that Alkaloids and phenolics distribution were highest in Annona senegalensis followed by Heliotropium indicum while Bryophylum pinatum has the lowest distribution. Flavonoids distribution was highest in Boyophyllum pinnatum followed by Annona senegalensis while Axonopus compressus has the least distribution. Saponins was highest in Heliotropium indicum followed by Bryophyllum pinnatum while axonopus compressus has the least. Tannins distribution was highest in Heliotropium indicum followed by annona senegalensis and Axonopus compressus while Bryophylum pinnatum has the least. I. Introduction The world is blessed with natural and unique medicinal plants (9). A medicinal plant is any plant, which in one or more of its organs contains active ingredients which can be used for therapeutic purposes or contain foundation compounds that can be used for the synthesis of useful drugs. Medicinal plants have invariably been a rich source of new drugs and many drugs in use today were either obtained from plants or developed using their chemical structure as templates (2). The medicinal value of these plants lies in bioactives phytochemical constituents that produce definite physiological action on the human body (3). Phytoconstituents are the natural bioactive compounds present in plants which combined with nutrients and fibers to form an integrated part of human defence mechanisms against diseases and stress conditions (8). Phytochemicals are basically divided into two groups that is primary and secondary constituents according to their function in the plant metabolism. Primary constituents comprises common sugars, amino acids, proteins and chlorophyll while secondary constituents consists of alkaloids, flavonoids, phenolics, saponins and so on (5). The important values of some plants have long been published but a large number of them remain unexplored as yet. So there is a necessity to explore their uses and to conduct pharmacognostic and pharmacological studies to ascertain their therapeutic properties (11). Annona senegalensis, axonopus compressus, Bryophyllum pinnatum and Heliotropium indicum were chosen to study because they were some of the traditionally used medicinal plants in the southwestern past of Nigeria for the treatment of inflammation and cancer. The present study aims at drawing attention to the phytochemical constituents of these plants and comparing them with a view to providing useful information towards effective utilization of these plants. And also bring into focus the scientific rationale behind the usage of these plants in traditional medicine.