EFFECT OF DIFFERENT PLANT ORIGINS AND CLIMATIC CONDITIONS ON THE TOTAL PHENOLIC CONTENT AND TOTAL ANTIOXIDANT CAPACITY OF SELF-HEAL (PRUNELLA VULGARIS L.)

The cultivation methods for medicinal plants ought to guarantee higher yields of active constituents in the final products. However, due to the predicted climatic changes, the present agricultural systems have to be modified. According to previous reports, the quality and quantity of active constituents accumulated in medicinal plants are highly affected by climatic conditions. Climatic changes will result in several stress effects on the plants both under cultivation and in their natural habitats. In the last years it was proven that the accumulation of several terpenoids and phenolic compounds can increase as a result of stress response reactions. Since phenolic compounds can be regarded as “multifunctional” antioxidants due to stress effect, the amount of these chemical substances can raise significantly. Self-heal (Prunella vulgaris L.) populations were evaluated in different habitats of Hungary and Italy in 2007. According to our results, the total phenol content (TPC) as well as the total antioxidant capacity (TAC) of the samples was affected by the sunnier, warmer weather conditions in Italy. In fact, plants coming from Monte Pisani and from the Botanical Garden of Lucca were characterised by significantly higher TPC and TAC values than the Hungarian originated samples. The altered climatic conditions (direct sun instead of half shadow, higher temperature) during the cultivation of the same genotypes resulted in a similar tendency. Compared to the woodland natural habitats, in the cultivated plants the level of TPC and TAC increased significantly.