Reducing blood lipid and antioxidant activities of tea flower extracts

Tea flower extract was prepared by supercritical CO2 extraction and the tea flower residue was extracted by ethanol.The reducing blood lipid and antioxidant activities of these two extracts were investigated. Bile salt-binding capacity in vitro and the clearance of superoxide anion, hydroxide radical and DPPH radical of the samples were tested in order to measure their reducing blood lipid and antioxidant activities.Results showed that tea flower extract and residue extract had the highest adsorption rate to sodium taurocholate and sodium glycocholate when the concentration was 32mg /mL ( the highest concentration in this experiment) . The residue extract had a similar adsorption rate to cholestyramine. The bile salt adsorption rate of residue extract and cholestyramine were higher than that of tea flower extract by supercritical CO2 extraction.Compared with BHT, the clearance rates of superoxide anion and hydroxide radical were higher in residue extract, but the clearance rates of DPPH radical was a little lower in residue extract.The three free radical clearances of the residue extract and BHT were higher than that of the tea flower extract by supercritical CO2 extraction.