Green tea ethanolic extract (GTE) preparation
Green tea sample was purchased from commercial sources (Institute of Medicinal Plants
Research “Dr Josif Pančić”, Pančevo, Serbia). Dried leaves were reduced to a fine powder
and extracted with ethanol (70% v/v) by percolation, as described in European
Pharmacopeia 6.0 (Ph. Eur. 6.0, 2007). GTE was obtained after evaporation to the dryness
in vacuo under 40 ºC and extraction yield was 25%. Chemicals, reagents and solvents used
in the experiment were of analytical grade.