Plant extracts
Dried and pulverized leaves (2.2 kg) were exhaustively extracted with ethanol. After filtration and concentration under reduced pressure the aqueous residue was sequentially extracted with organic solvents of increasing polarities, to afford the new extracts: dichloromethane (VD), ethyl acetate (VA) and n-butanol (VB) extracts, in this order, as well as (LW), which is the water-soluble remaining extract