利用对虾消化腺丝氨酸蛋白酶制备鲍鱼外套膜ACE抑制肽

利用鲍鱼加工副产物外套膜制备具有抑制血管紧张素转移酶（angiotensin converting enzyme，ACE）活性的生物活性肽，为鲍鱼加工副产物的高值化利用提供新思路。采用从凡纳滨对虾消化腺中制备的丝氨酸蛋白酶，酶解皱纹盘鲍外套膜蛋白，以酶解物ACE抑制活性为评价指标优化条件。酶解液通过3 kDa超滤膜后，活性组分经过Superdex peptide 10/300 GL凝胶过滤柱和反相高效液相色谱（reversed-phase high performance liquid chromatography，RP-HPLC）分离纯化，利用液相色谱-质谱（liquid chromatography tandem mass spectrometry，LC-MS/MS）鉴定纯化肽的氨基酸序列。结果显示，酶解液的ACE抑制率为13.42%，经3 kDa超滤膜初步分级后，相同浓度下，小于3 kDa的组分ACE抑制率为53.25%。经凝胶过滤柱和反相高效液相色谱柱进一步分离后，从ACE抑制活性最高的峰中鉴定得到5个肽段，序列为LGDSFYYGK、LVNEVTEFAK、VDEVGGEALGR、MFLSFPTTK、VATVSLPR，说明活性峰是多肽混合物。本研究利用鲍鱼外套膜制备ACE抑制肽，可以为鲍鱼及对虾加工副产物的高值化利用提供理论参考。

Preparation of Angiotensin Converting Enzyme (ACE) Inhibitory Peptide from Abalone(Haliotis discus hannai) Mantle Membrane by Serine Protease in Shrimp(Litopenaeus vannamei) Digestive Gland

The abalone (Haliotis discus hannai) mantle processing by-products was used to prepare biologically active peptides with inhibiting the activity of angiotensin converting enzyme (ACE), which provided a new idea for the high-value utilization of abalone processing by-products. The serine protease prepared from the digestive glands of Litopenaeus vannamei was used to enzymatically hydrolyze the mantle proteins of Haliotis discus hannai. The ACE inhibitory activity of the enzymatic hydrolysate was used as the evaluation index to optimize the digestion conditions. After the enzymatic hydrolysis solution passed through the 3 kDa ultrafiltration membrane, the active components were separated and purified by Superdex peptide 10/300 GL gel filtration column and reversed-phase high performance liquid chromatography (RP-HPLC). Liquid chromatography tandem mass spectrometry (LC-MS/MS) was used to identify the amino acid sequence of the purified peptide. The results showed that the ACE inhibition rate of the enzymatic hydrolysate was 13.42%. After preliminary separation by the 3 kDa ultrafiltration membrane, the ACE inhibition rate of the fractions less than 3 kDa at the same concentration was 53.25%. After further purification by gel filtration column and RP-HPLC, five peptides were identified from the peak with the highest ACE inhibitory activity. The sequences were LGDSFYYGK, LVNEVTEFAK, VDEVGGEALGR, MFLSFPTTK, VATVSLPR, indicating that the active peak was a mixture of peptides. Preparation of ACE inhibitory peptides using abalone mantle could provide a theoretical reference for the high-value utilization of the processing by-products of abalone and prawn.