Purification process influence on green tea extracts’ polyphenol content and antioxidant activity

摘要

The research examined green tea ethanol extract, subjected to different purification processes with use of active carbon, bleaching earth, and mixture of acetone, acetic acid, water, with or without earlier hexane treatment. Purified extracts were examined according to total polyphenols content, antioxidant activity in linoleic acid emulsion and antiradical activity in DPPH? radical scavenging method. Highest polyphenol content was evaluated in the extract purified with bleaching earth, lowest however in purified with solvents mixture. Antioxidant activity of green tea extracts in linoleic acid emulsion indicated that highest antioxidative effectivity coefficient (Aec) values represented sample purified with active carbon and solvents mixture. Highest DPPH? radical scavenging activity was found in sample purified with solvents mixture, other samples however represented close activity. The present research indicated that plant extracts purification processes resulted in decrease of total polyphenols content, however without its antioxidant activity decrease.