薏苡仁谷蛋白源降压肽稳定性研究

摘要

目的：研究薏苡仁谷蛋白源降压肽的溶解性、pH、温度以及耐酶稳定性。方法：采用超滤法（截留分子量3KDa）对薏苡仁谷蛋白的胃蛋白酶水解液进行分离；指数测定方法测定其小分子量组分的溶解度，利用高效液相色谱法考察pH、温度和消化酶对小分子量组分的降压重要靶点血管紧张素转化酶（ACE）活性的影响。结果：谷蛋白源降压肽具有较高的溶解度（＞70％）且不受pH影响；在pH 2．0～pH 12．0和温度0～100℃之间具有较好的稳定性；经胃蛋白酶、α－胰凝乳蛋白酶和胰蛋白酶消化作用后其ACE抑制活性显著增强。结论：谷蛋白源降压肽具有较高的溶解性和稳定性，为薏苡仁谷蛋白源降压肽的进一步开发研究提供了理论支持。%Objective:To investigate the solubility, pH, temperature and enzyme resistance stability of antihypertensive peptides derived from Adlay glutelin.Methods:Ultrafiltration ( a 3KDa molecular weight cut-off) was firstly employed for separation of the Adlayglutelinhydrolysates prepared with pepsin, and index determination method was then used to determine the solubility of small molecular weight fraction.The effects of pH, temperature and digestive enzymes on its angiotensin I-converting enzyme ( ACE) activity were observed,and one of main antihypertensive target was investiga-ted by reversed-phase high performance liquid chromatography ( RP-HPLC) .Results:The solubility of antihyperten-sive peptides (≤3KD) derived from Adlayglutelin was high (>70%) and not affected by pH.Furthermore, the anti-hypertensive peptides manifested a good stability at pH (2.0~12.0) and temperature (0~100℃).The ACE inhibito-ry activity was significantly enhanced after digestion by pepsin,α-chymotrypsin and trypsin.Conclusion:The antihy-pertensive peptides derived from Adlay glutelin have a higher solubility and stability, and these data provide guidance for further research and development of antihypertensive peptides from Adlayglutelin.