在pH 7.35、温度57.2 ℃、水解时间4 h、虾肉/虾头为1∶ 1,底物浓度为20%(W/V)的条件下,利用虾头的内源酶酶解虾肉(南美白对虾),制备了具有血管紧张素转化酶(ACE)抑制活性的酶解产物,其对ACE的抑制率为41.9%(2 mg·mL-1).通过凝胶过滤层析测定出酶解产物的分子量分布较广,在7.4×104至29.7之间.分子量在2.7×103以下的凝胶层析组分占酶解产物氨基酸总量的83.1%.收集的高活性组分分子量在959～338之间,其IC50为0.32 mg·mL-1苯丙氨酸、疏水氨基酸(亮氨酸、异亮氨酸和缬氨酸)和芳香族氨基酸(脯氨酸、酪氨酸和色氨酸)占氨基酸总量的42.33%.体内试验的结果显示,南美白对虾的虾肉虾头内源酶酶解产物经灌喂原发性高血压老鼠后显示较强的降血压活性.%Hydolysate of shrimp meat hydrolyzed by the endogenous enzymes of the head of Penaeus vannamei, with angiotensin I-converting enzyme (ACE) inhibitory activity of 41.9% (2 mg·mL-1), was prepared under the conditions of pH 7.35, temperature 57.2 ℃, hydrolysis time 4 hours, shrimp head/shrimp meat 1∶ 1, and substrate concentration 20%. The hydrolysate had a broad molecular weight distribution (between 7.4×104 and 29.7). Fractions with molecular weight under 2.7×103 covered 83.1% of the total hydrolysate. Fractions with molecular weight between 959-338 exerted an inhibitory activity of IC50 0.32 mg·mL-1. Phenylalanine, hydrophobic (Leucine, Isoleucine and Valine ) and aromatic(Proline, Tyrosine and Tryptophan ) amino acids covered 42.33% of the total amino acids of Peak C. Results of the experiments in vivo showed that the hydrolysate exerted a significant antihypertensive activity in spontaneously hypertensive rats after oral administration.
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