Study On ACE-inhibitory And Antioxidant Activities Of Three-spot Hippocampus Hydrolysis Peptides

Hippocampus is widely distributed in China, which is a rich resource of Hainan. With the development of the hippocampus cultural techniques, some regions of China have been established industrialized and large-scale breeding bases, which can provide enough clean and healthy hippocampus. Hippocampus derivatives have multiple biological activities, including anoxia, antioxidant, anti-fatigue, anti-aging, anti-tumor. Hippocampus is a precious marine medicinal, and it is valuable for study and development of hippocampus. Therefore, the objective of this study was to investigate potential ACE inhibitory peptides and antioxidant peptides from the hydroly sates of three-spot hippocampus.In this paper, the ACE-inhibitory activity of three-spot hippocampus peptides were evaluated by studying the preparation technique of three-spot hippocampus enzymatic hydrolysate, screening chromatography separation of ACE-inhibitory peptides and establishing the model. The enzymatic hydrolysate with ACE-inhibitory activity was prepared by alkaline protease, and then separated and purified by gel filtration chromatography. After determination, the lower molecular fraction exerted the highest ACE-inhibitory activity (IC50value was0.91mg/mL). The composition of amino acids in it was analyzed, and the test result indicated that the content of hydrophobic amino acids was50.48%. In addition, it was suggested that the ACE-inhibitory peptides acted as ’prodrug-type’ inhibitor after establishing the model of artificial gastrointestinal digestion. ACE-inhibitory activity was increased significantly under condition of digestive enzyme digestion.This paper also studied the antioxidant activity of three-spot hippocampus. Using enzymatic hydrolysis to prepare three-spot hippocampus antioxidant peptides and the papain hydrolystae showed the highest DPPH scavenging activity. It was subjected to consecutive purification by loading onto a of Sephadex G-25gel filtration. Elution peaks were fractionated into three portions (A-C)-Each fraction was lyophilized and measured for antioxidative activity against DPPH radical. Fraction C exhibited the highest scavenging potencies on the DPPH radical. DPPH radical scavenging rate of fraction C reached78.00%at the concentration of1mg protein/ml. Fraction C was employed for further purification on anion exchange chromatography. The fraction was divided into five peaks (C1-C5). Fraction C5exhibited the highest scavenging potencies on the DPPH radical. DPPH radical scavenging rate of fraction C5reached70.89%at the concentration of200μg protein/ml. Then fraction C5was employed for desalination and fraction DS was obtained. Fraction DS was further separated by high performance liquid chromatography (HPLC).3peaks designated as DS1-DS3, were collected separately. Fraction DS3had higher antioxidant activity, and its IC50values of DPPH radical scavenging activity was58.52μg protein/ml.