Extraction and free radical scavenging activity of polysaccharide from 'Anji Baicha' (Camellia sinensis (L.) O. Kuntze)

In this study, the optimization of the extraction conditions of polysaccharide from 'Anji Baicha' (Camellia sinensis (L.) O. Kuntze) (AP) was investigated by response surface methodology (RSM). Three main independent variables (extraction temperature, time, ratio of water to raw material) were taken into consideration. And then the free radical scavenging activities of the sample were investigated including scavenging effects of superoxide and hydroxyl radicals. The RSM analysis showed good correspondence between experimental and predicted values.. The optimal condition to obtain the highest yield of AP was determined as follows: temperature 76.79 degrees C, time 2.48 h, ratio of water to material 22.53 mL/g. For the free radical scavenging activity, the IC50 values of Vc and AP were 7.78 and 83.25 mu g/mL. And for the scavenging effect on hydroxyl radical, that of AP and Vc were 1.80 and 1.69 mg/mL. AP showed excellent antioxidant activity. This exhibited AP had a good potential for antioxidant. The purification and structure needs to be study in further. (C) 2015 Elsevier B.V. All rights reserved.