Determination of flavones in species of Thymus L. (Lamiaceae) from Macedonian flora

Certain biological and pharmacological effects of the Thymus species have been experimentally proved, such the expectorant (1), spasmolytic (1-3), antibacterial (1,4), antifungal (5), antioxidant (6-9), etc. These activities are due to the specific composition of the essential oils (1, 4-9), flavonoids (1-3, 9), phenolic acids (4) and other chemical constituents of Thymus. Beside the data concerning the composition of the essential oils, a lot of literature data about Thymus also consider information about the flavonoids present in this species. A very comprehensive work is presented in the papers of Spanish authors where the distribution of flavone aglycones in a number of Thymus species is given (10-15). The flavonoids have also been investigated in representatives of Macedonian Thymus species, and luteolin, apigenin, diosmetin, eriodyctiol and naringenin were identified as free flavonoid aglycones in many of them (16-18). In respect to the literature data, a lot of information on the identification and isolation of flavonoids is available, which cannot be said for quantitative data on these components of Thymus. Determination of their content could be important because the flavonoids are involved in spasmolytic, antioxidant and other activities of Thymus sp. The aim of the present study is to establish methods for determining the total flavonoid content as well as the content of the main flavone aglycones in Macedonian Thymus species.