Materials
Green tea plant (Camellia sinensis ) belongs to the familyTheaceae was obtained from Isfahan province (Iran), lecithin (99%, granular phosphatidylcholine) was procured from Across Company (USA). Ethanol, glycerol, 2-2-diphenyl-1-pycrylhydrazyl (DPPH) and Folin-ciocalteu reagent were prepared from Merck Company, Germany, Particle size and Zeta-Sizer analyzer (Horiba scientific Instruments, SZ-100 Series Germany), ultracentrifuge (Herolab, Hicen, Germany), spectrophotometer model UV-6600 (Spectro Flex, Germany).