石斑鱼肉肽的酶法制备工艺及其抗氧化性

以冰鲜石斑鱼肉为原料,采用碱性蛋白酶酶解的方法制备蛋白肽。以水解度和1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率为评价指标,在单因素试验的基础上,运用正交试验设计优化肽的制备工艺;利用DPPH自由基法、2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐(2,2’-azinobis(3-ethylbenzothi azoline-6-sulfonic acid)ammonium salt,ABTS)自由基法、羟自由基(·OH)法和铁氰化钾还原法评价酶解物的抗氧化性。结果表明:石斑鱼肉肽的最佳制备条件为:酶解温度55℃、酶解p H 9、酶用量5 000 U/g、底物质量浓度8 g/100 m L、酶解时间5 h;石斑鱼肉肽酶解物具有较强的抗氧化性,清除DPPH自由基能力、ABTS+·能力、·OH能力和总还原力均随酶解物质量浓度的增加而增强;酶解物清除DPPH自由基、ABTS+·、·OH的半抑制浓度(IC50)值分别为(1.18±0.26)、(0.89±0.05)mg/m L和(0.35±0.02)mg/m L。

Enzymatic Preparation and Antioxidant Activities of Bioactive Peptides from Epinephelus Meat

The fresh meat of Epinephelus was hydrolyzed with alkaline protease to prepare peptides. Based on degree of
hydrolysis and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, an orthogonal design combined with
single facto experiments was applied to optimize enzymatic hydrolysis conditions for peptide preparation. Antioxidant
activities of peptides were evaluated by four different methods, DPPH, 2,2’-azinobis (3-ethylbenzothi azoline-6-sulfonic
acid) ammonium salt (ABTS) and hydroxyl radical scavenging assays, and potassium ferricyanide reduction method. The
results showed that the optimum hydrolysis conditions were 55 ℃, 9, 5 000 U/g, 8 g/100 mL and 5 h for temperature, initial pH,
enzyme dosage, substrate concentration and hydrolysis duration, respectively. The antioxidant activity assays showed that the
hydrolysates presented strong antioxidant activity. DPPH radical scavenging activity, ABTS radical cavenging activity, hydroxyl
radical scavenging activity and potassium ferricyanide reducing power of hydrolyzates from Epinephelus meat were concentration
dependent. The half inhibitory concentration (IC50) for DPPH radical scavenging activity, ABTS radical scavenging activity and
hydroxyl radical scavenging activity were (1.18±0.26), (0.89±0.05) and (0.35±0.02) mg/mL, respectively.