PHYTOCHEMICAL ANALYSIS, PROXIMATE, MINERAL AND AMINO ACID COMPOSITION OF THE LEAVES OF WEDELIA TRILOBATA (L.) HITCHC.

Abstract

Phytochemicals present in plants are responsible for the biological activities and therapeutic properties of the various medicinal plants. They function as antioxidants in health promotion by preventing oxidant-damage which is the main cause of many diseases. This study reveals the phytochemicals in different solvents of the leaves of wedelia trilobata growing in Yola north local government area of Adamawa State Nigeria. The dried leaves of W. trilobata was used to determine the proximate composition by standard methods, minerals composition was determined using AAS and the amino acid composition and the quantitative composition of the phytochemicals using HPLC. The proximate composition shows the plant is rich in crude protein and fibre. The adequate ash content accounts for the abundance of minerals. In this study, heavy metals were not detected. Manganese was the most abundant with a value of 207.15 mg/100 g, copper was the least 2.77 mg/100 g, the elements detected were Ca, Fe, Mg, Zn, Cu, Mn. Nineteen (19) amino acids were detected in the leaves of W.trilobata. all the essential amino acids were present in reasonable quantities. Tyrosine 9.2 mg/100 g was the most abundant followed by phenylalanine, glycine, and aspartate with values 8.78, 7.83 and 5.14 mg/100 g respectively. The percent of ideal essential amino acids in W.trilobata are higher than World Health Organization (WHO) standards except for leucine, lysine and threonine with values 6.6/2.29, 5.8/4.53, 3.4/3.36 percent of total W.trilobata/WHO respectively. The quantitative phytochemical composition determined using HPLC showed that phenolics had the highest concentrations in all the solvents used, followed by tannins and phlobatanins was the least. The phytochemical, mineral, proximate and amino acid contents of this plant must have contributed to the medicinal properties of the plant.