J Agric Food Chem. 2013 May 1;61(17):4097-100. doi: 10.1021/jf4001378. Epub 2013 Apr 19.
In the present study, a novel angiotensin I-converting enzyme (ACE)-inhibitory peptide, P-2a2, was purified to homogeneity from walnut protein hydrolysate by ultrafiltration, consecutive column chromatography, and high-performance liquid chromatography. The purified peptide was characterized by matrix-assisted laser desorption ionization time-of-flight mass spectrophotometry and a liquid-phase peptide sequencer. The molecular mass of P-2a2 was tested to be 1033.42 D. Its amino acid sequence was determined to be Trp-Pro-Glu-Arg-Pro-Pro-Gln-Ile-Pro. The potent ACE-inhibitory peptide is an enneapeptide and shows a high ACE-inhibitory activity, with an IC50 value of 25.67 μg/mL.
在本研究中，通过超滤、连续柱层析和高效液相色谱法，从核桃蛋白水解物中纯化出一种新型的血管紧张素转化酶（ACE）抑制肽 P-2a2。该纯化肽通过基质辅助激光解吸电离飞行时间质谱和液相肽测序仪进行了表征。P-2a2 的分子量测试为 1033.42 D。其氨基酸序列被确定为色氨酸-脯氨酸-谷氨酸-精氨酸-脯氨酸-脯氨酸-谷氨酰胺-异亮氨酸-脯氨酸。这种有效的 ACE 抑制肽是一种九肽，具有很高的 ACE 抑制活性，IC50 值为 25.67 μg/mL。
