Qualitative and quantitative evaluation of some herbal teas commonly consumed in Nigeria

Abstract

Herbal tea can be use for therapeutic or nutritional purposes, depending on the chemical constituents present. This study aims at evaluating phytochemical, physicochemical parameters and elemental contents of herbal teas commonly consumed in Nigeria. Level of essential and toxic metals in medicinal plants is a matter of great concern all over the world. Six different brands of herbal teas were analysed in this study. Phytochemical screening results showed the presence of tannins, steroids, terpenoids, saponins, cardiac glycosides, flavonoids, alkaloids and phlobatannins, while the physicochemical parameters which includes moistures content, ash, water extractive and alcohol extractive matter values ranges from 7.55 to 21.20, 5.52 to 9.28, 8.86 to 14.80 and 4.22 to 7.05%, respectively. Atomic absorption spectroscopy (AAS) was used for the elemental analysis of different teas in which the content ranges from 0.83 to 2.63, 3.28 to 5.96, 7.45 to 86.67, 0.53 to 2.85 and 1.11 to 9.73 µg/g for chromium (Cr), iron (Fe), manganese (Mn), Lead (Pb) and zinc (Zn), respectively. The outcome of this study serves as an important contribution to knowledge in establishing quality parameters for the standardization of herbal tea in Nigeria. Key words: Phytochemical, physicochemical, elemental analysis, herbal tea.