Abstract: The ultrasonic was used to extract Se-enriched green tea functional components. The extraction pararmeters were optimized by L9(34) orthogonal design. And the composition of Se-enriched tea functional components was researched. The antioxidant activity of Se-enriched green tea functional components was assessed by FTC method and DPPH method. The optimized parameters were as follow: 50% (W/V) ethanol as solvent, ultrasonic power of 250W, ratio of solid/liquid of 1:15, extracting for 2 times at 50℃ for 1.5 hours each time. The yield was 43.76%. The antioxidant activity of the extracts under the optimized condition, which contained Selenium 4.35±0.11μg/g, tea polyphenol (55.84±2.31)%, polysaccharide (13.37± 3.02)%, protein (25.75±4.05)%, theine (5.99±0.01)%, was stronger than the extracts under other technology parameters and positivec ontrolα -tocopherol.

Key words: Se-enriched, ultrasonic, functional components, antioxidant