Elemental composition of Cyrtanthus obliquus and Lippia javanica used in South African herbal tonic, Imbiza

Abstract

Imbiza is a herbal tonic, which has gained popularity amongst South Africans as an immune booster and for the treatment of many minor and chronic illnesses. Main ingredients of Imbiza are extracts from two medicinal plants namely Cyrtanthus obliquus and Lippia javanica. The concentrations of various elements in these two plants are examined. The total and water extractable elemental concentrations were determined in both the plants. The elemental concentrations in the water extracts more closely represent concentrations in the herbal tonic. Concentrations of selected elements in C. obliquus bulbs collected from eight market sites around the KwaZulu-Natal province were investigated. The levels of the elements in decreasing order were Ca>Mg>Fe>Zn>Mn>Cu≈Se>Pb>Cr for total concentrations; and Ca>Mg>Fe>Zn>Mn for water extractable forms. Elemental levels in C. obliquus bulbs were dependent on the source, which suggested the importance of collection sites on elemental levels. A high percentage of Zn (77.5–91.5%) was found in water extracts.The levels of selected elements in L. javanica leaves collected from ten different locations around the KwaZulu-Natal province were also investigated. The levels of the elements were found to be in the decreasing order of Ca>Mg>Fe>Zn>Mn>Cu>Se>Cr>Pb>Co>Cd for total concentrations and Ca>Mg>Fe>Zn>Cu>Cr>Pb for water extractable forms. It was evident from the study that the herbal tonic was a good source of Ca and Mg, thus accredited as a viable immune booster and toxic metals were below the recommended levels in the investigated samples.