热变性对海参肠酶解物活性的影响

为充分利用海参蛋白质资源,以海参肠为原料,结合热变性预处理来制备海参肠活性多肽,利用中性蛋白酶酶解两组海参肠匀浆液(100℃预处理10 min的变性组和未变性组),并比较分析两组蛋白的水解度、可溶性蛋白、三氯乙酸(TCA)可溶性寡肽的含量、肽得率、分子量分布以及抗氧化能力,检测层析分离后样品的蛋白含量及还原能力,探究热变性预处理对多肽性质的影响。结果表明,经过变性处理后,海参肠酶解液水解度由23.76%提高到37.28%,肽得率由13.97%±1.25%提高到25.13%±1.59%。Superdex Peptide 10/300GL凝胶过滤色谱分析表明,变性组海参肠多肽组分的分子量主要分布范围为0.5~3 kDa,占水解液的57.29%,且变性处理组的ABTS⁺与DPPH自由基清除率最高可达0.51 Trolox equi/μL Sample与90.95%。以上结果说明,结合变性预处理工序,利用中性蛋白酶可获得较低分子量范围的海参肠多肽,具有潜在的开发价值。

Effect of Heat Denaturation on the Activity of Sea Cucumber(Stichopus japonicas)Guts Hydrolyzates

In order to make full use of the sea cucumber protein resources,sea cucumber guts were used as a raw material,which combined with heat denaturation pretreatment to prepare sea cucumber guts activity polypeptide and explored the effect of heat denaturation pretreatment on the properties of peptides. Using neutral proteases digest the two sea cucumber intestine homogenates(the denatured group with pretreatment at 100℃ for 10 min and non-denatured group),and compared the degree of hydrolysis,soluble protein and trichloroacetic acid(TCA)soluble oligopeptide content,peptide yield,molecular weight distribution,and antioxidant capacity of enzymolysate. And the protein content and reduction capacity of separation were determined. The results showed that,after degeneration,the degree of hydrolysis increased from 23.76% to 37.28%,and the peptide yield increased from 13.97%±1.25% to 25.13%±1.59%. The molecular weight of primary peptide fraction in hydrolysates(denaturated)of sea cucumber guts ranged from 0.5 to 3 kDa which determined by gel filtration chromatography on Superdex Peptide 10/300 GL,accounting for 57.29% of the hydrolysates,and the ABTS+ and DPPH free radical scavenging rate up to 0.51 Trolox equi/μL Sample and 90.95%. These results suggested that the sea cucumber guts peptides with low molecular weight,prepared with a combination of denaturing pretreatment and neutrase hydrolysis,would have potential value for exploitation.