Etude morphologique, biochimique, physiologique et biologique de quelques populations de Teucrium polium L. Capitatum dans l’Est algérien

Abstract

The purpose of our work has focused on the study of Teucrium polium L. Capitatum, which is a widespread medicinal plant in algerian steppes. Several study topics were investigated such as the morphology, physio-biochemical constituents and biological effects. The morphological analysis consisted of ten populations sampled at different habitats in eastern Algeria. This study revealed that the leaves have the lowest number (five out of ten) of types of trichomes, followed by the calyx and corolla with eight types for each. This confirms the absence of intraspecific variability within the study populations. Furthermore, the analysis of relationships between morphological characteristics and environmental factors of their habitat showed that the latter influences the length of trichomes. The use of one-dimensional electrophoresis technique on polyacrylamide gel in the presence of detergent (SDS-PAGE) allowed to determine the total protein profiles of the ten study populations. The similarity coefficients of polypeptide bands indicated high similarity between populations. Biochemical analyzes of the three phenotypes of T. polium L. Capitatum showed that extracts of purple phenotypes were richest in anthocyanins, soluble sugars and carotenoids compared with pink and white phenotypes enlightening there by the importance of flower color. The combination of certain chemical analysis methods, spectrophotometry (UV-visible) and chromatographic (HPLC) have identified three flavonoids including mostly the cyanidin and two other flavonoids, quercetin and caffeic acid. The evaluation of the antioxidant potency, that was conducted using the method of trapping the free radical DPPH and that of iron reduction FRAP, revealed that the extract of Biskra population showed higher reducing capacity compared to that of Sétif, with a strong trapping of DPPH● radicals. As regards to the antibacterial activity, it appears that extracts from two populations have acceptable antibacterial properties. The pharmacological effect of T. polium L. Capitatum showed an interesting diuretic property.