Antioxidant properties of Moldavian dragonhead (Dracocephalum moldavica L.)

The antioxidant power of acetone oleoresin (AO), deodorized acetone extract (DAE) and methanol extract (ME) isolated from Moldavian dragonhead (Dracoc ephalum moldavica L.) leaves and flowering parts was tested in stripped cor n oil and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging system. T he activity of ME or rosmarinic acid mixtures with alpha -tocopherol was al so determined in corn oil. The results showed that methanol was a considera bly more effective solvent to extract antioxidative substances from dragonh ead than acetone. Dragonhead ME was efficient both in retarding corn oil pe roxidation and in scavenging DPPH free radicals. The effectiveness of drago nhead AO isolated from the whole herb and DAE isolated from deodorized herb was significantly lower. Their activities were similar in DPPH radical sca venging, whereas DAE was more efficient in stripped corn oil than AO. Drago nhead ME was fractionated by thin-layer chromatography (TLC) and high-perfo rmance liquid chromatography (HPLC) and the identification of the component s was assessed by their retention times and UV spectra. Rosmarinic acid, fo und in dragonhead for the first time, was the major antioxidant constituent . The presence of apigenin, which can contribute to the antioxidant activit y of dragonhead was also reported for the first rime. Other TLC and HPLC fr actions were preliminary characterized, however further investigations are needed to elucidate the structure of other compounds.