Abstract.

Aim of this research is to determine radical-scavenging potential of extracts from intact plants and in vitro cultures, gained form Astragalus thracicus Griseb. and to prove the presence of the flavonoid orientin by the HPLC spiking method in them.

In this research is used the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The activity of the gained extracts is measured as an equivalent of ascorbinic acid (EqAA) and hyperoside (EqH). Aerial parts from intact plants possess the highest level of activity, evaluated to 1094.01 µg EqAA and 1166.82 µg EqH. Similar activity is found in extract from plants, grown on MS media (968.77 µg EqAA and 1036.50 µg EqH).

The presence of the flavone orientin by the means of HPLC spiking method is proved in all of the investigated aerial extracts, as it is determined in insignificantly small amounts in the roots.