Extraction Optimizing Of Protein From Sheep Liver And Its Antioxidant Activity Assessment

Natural antioxidant functional food and natural antioxidants are two hot topics of modern Bioscience in the recent years. The evaluation antioxidant activity of natural resources become a new research trend for Food Science.Sheep liver is a major byproduct of sheep meat processing. It contains a lot of nutrients, especially complete protein. The sheep meat production creats a mounts of liver which only small quantity is used for domestic consumption in a fresh form. However, the sheep liver is not processed deeply.The phosphate buffer solution was used to extract sheep liver protein in this study and the extraction condition of protein was analyzed according to response surface methodology. By using DPPH, pyrogallol auto oxidation and salicylic acid colorimetry method to study antioxidant activity of sheep liver protein in vitro.The results showed that:1. The contents of crude protein in fresh sheep liver were17.36%.2. The optimum extraction condition as below:extraction time5h,extraction temperature17℃, liquid-solid ratio7.8g/ml and the phosphate buffer solution pH7.5. The extraction rate of the protein was80.27%under this optimum extraction condition.3.The protein concentration extracted at25mg/ml showed good scavenging activity on DPPH·,·OH and O2·. The scavenging rate were61.62%,65.64%and65.78%, respectively.