Identification and characterization of phytochemicals and constituents in Desmodium velutinum stem using high-performance liquid chromatography (HPLC)

Abstract

The aim of this study was to analyse and identify phytochemicals and bioactive constituents present in Desmodium velutinum stem. Fresh stems of Desmodium velutinum were air-dried at room temperature for 3 days. The stems were pulverized into a fine powder which was extracted with methanol (80% v/v). The concentrated extract was fractionated using n-hexane, ethylacetate, and aqueous methanol. Phytochemical analyses and bioactive composition were done using standard methods and HPLC. The fractionation of 40 g Desmodium velutinum stem methanol extract using aqueous methanol gave a 16 % percentage yield. The phytochemical analyses showed the presence of tannins, flavonoids, phenolics, and alkaloids with concentrations 5.02±1.22 mg/g, 2.64±0.01 mg/g, 7.02±1.18 mg/g and 3.61±0.04 mg/g respectively. The high-performance liquid chromatography (HPLC) analysis of the aqueous fraction of Desmodium velutinum stem showed the presence of different constituents of flavonoids, phenols, and tannins in varying concentrations. The flavonoids include rutin hydrate and apigenin. The phenols identified were p-coumaric acid, rutin, ferrulic acid, and apigenin while the tannins identified were tannic acid. These phytochemicals identified in Desmodium velutinum stem have been reported to possess antioxidant properties which may be used in preventing and alleviating diseases. Desmodium velutinum may therefore be a potential source of new drugs in orthodox medicine. Most of these phytocompounds form part of the components of Traditional Chinese Medicine as well as African Traditional Medicine.