Influence of the elemental composition of medicinal fruits on the results of their thermal analysis

Studies on the thermal decomposition and on the elemental composition of commercial raw plant materials used in medicine were performed. 16 independent samples of fruits originating from 12 medicinal plant species collected in 1988-92 were analysed. The thermal decomposition was performed using the derivatograph. The content of non-metallic (N, P, S, Cl, I and B) and metallic (Ca, Mg, Fe, Mn, Cu and Zn) elements was determined by spectrophotometric techniques after previous mineralization of sample. In order to obtain more clear classification of the analysed plant materials principal component analysis was applied. The interpretation of PCA results for three databases (thermoanalytical, non-metals and metals data sets) allows to state, that samples of fruits from the same plant species in the majority of cases are characterized by similar elemental composition and similar course of their thermal decomposition. In this way the differences in general chemical composition of medicinal plants raw materials can be determined.