Effects of Calendula officinalis L. and Taraxacum officinale Weber (Asteraceae) extracts on the production of OH radicals

Marigold (Calendula officinalis L., Asteraceae) and dandelion (Taraxacum officinale Weber, Asteraceae) are worldwide well-known plants with medicinal properties. This investigation showed that all extracts from flowers, leaves, stems and roots of C. officinalis L. and T. officinale Weber inhibited the generation of hydroxyl radicals which are determined following the chemical degradation of desoxyribose. The highest inhibitory effect was obtained with the ethylacetate extract of C. officinalis L. and ethylacetate or water extracts of dandelion flowers exhibited the highest OH radical scavenging activity. Considerable inhibitory effect was obtained with the chloroform and ethylacetate extracts of dandelion leaves. We also found a rather strong inhibitory effect of the water extract of stem, and ether or n-butanol extracts of dandelion root.