响应面试验优化酶解法制备海洋微藻微拟球藻抗氧化肽工艺

以海洋微藻饵料微拟球藻蛋白为原料，采用胃蛋白酶酶解制备微拟球藻抗氧化肽。以酶解产物的水解度和1,1-二苯基-2-三硝基苯肼自由基清除活性为评价指标，研究酶底比（质量百分比）、底物质量浓度、酶解温度和pH值对酶解产物的影响。在单因素试验的基础上，利用响应面法优化制备高抗氧化活性抗氧化肽的工艺条件，确定最佳酶解工艺条件为：底物质量浓度5.0?mg/mL、酶解温度32?℃、pH?1.36、酶底比6%。在最佳酶解条件下实际测得微拟球藻抗氧化肽的DPPH自由基清除率为51.85%。

Optimization of Enzymatic Preparation of Antioxidant Peptides from Protein Hydrolysate of the Marine Microalgae Nannochloropsis by Response Surface Methodology

Protein from the marine microalga Nannochloropsis was extracted and hydrolyzed with pepsin to prepare antioxidant peptides. The effects of enzyme-to-substrate ratio, substrate concentration, hydrolysis temperature and pH on the degree of hydrolysis (DH) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of hydrolysates were investigated and the process conditions were optimized using one-factor-at-a-time (OFAT) method and response surface methodology (RSM). The optimal hydrolysis conditions were determined as follows: substrate concentration, 5.0 mg/mL; temperature, 32 ℃; pH, 1.36; and enzyme-to-substrate ratio, 6%. The hydrolysate prepared under these conditions could scavenge 51.85% of DPPH free radical.