The Study On Isolation And Biological Activity Of Hydrophobic Peptides From Deer Antler Blood Hydrolysate

Deer antler blood is a precious medicinal material in chinese tradition. Many studies demonstrated that the deer antler blood has many bio-activities, such as promoting metabolism activity, immunostimulating activity, antioxidative activity, ACE inhibitory activity and so on. The protein concentration of deer antler blood is as high as 225.2mg/mL, which contains most essencial amino acids. The various bio-activities of deer antler blood have a close connection with its special protein amino sequence. This research is focused on the antioxidative activity and ACE inhibitory activity of deer antler blood hydrolysates, the relationships between hydrophobicity, DH and antioxidative activity, ACE inhibitory activity. The following were the results:First the research selected 4 different protein enzymes to hydrolyze the deer antler blood, the results were as follows: the hydrolysate prepared by Alcalase for 3 hours has the highest ACE inhibitory activity, which was 90.63%;the hydrolysate prepared by acidic proteinase for 3 hours has the highest DPPH·clearage,which was 23.10%; the hydrolysate prepared by papain for 5 hours has the highest OH·clearage, which was 90.67%; the antioxidative activity has a significant corelation with DH, while the ACE inhibitory activity has a significant corelation with DPPH·clearage.DA201-C Macroporous were used for fractionation of ACE inhibitory and antioxidative peptides from the hydrolysis by gradient ethanol elution. Amino acid analysis result suggests that different fractions have different hydrophobicities. Different ethanol elutions got different hydrophobicities, so the hydrolysate can be separated by hydrophobicity. 75% ethanol fraction has the highest ACE inhibitory activity, which has a significant correlation with hydrophobicity. After ultrafiltration with membranes of MW cut-off 6000Da, the antioxidative activity and ACE inhibitory activity did not significantly increase.The activated carbon was used to separated the hydrolysate by different amino composition. It was shown that the adsorbtion capacity was influenced by flow rate, pH, and concentration of hydrolysate. With the conditions pH=4, 0.5BV/h flow rate, and 10mg/mL concentration, most of the hydrolysate was adsorbed. Desorption was achieved by washing with 6 different elutions and the antioxidative and ACE inhibitory activities of fractions were determined. The fraction eluted by 5% acetic acid and enthanol(1:1) got the highest antioxidative and ACE inhibitory activities, and the hydrophobicity and aromatic amino acid content were significantly increased. RP-HPLC was used to separate this fraction, and 11 fractions(R1-R11) were obtained. R9 had the highest OH·clearage, while R-11 had the highest DPPH·clearage and ACE inhibition. After LC/MS, 3 peptides were obtained: NSAW,YDQW,YDAW.