Jakubczyk Anna, Baraniak Barbara
Department of Biochemistry and Food Chemistry, University of Life Sciences, Ulica Skromna 8, 20-704 Lublin, Poland.
Biomed Res Int. 2014;2014:438459. doi: 10.1155/2014/438459. Epub 2014 Aug 28.
Pea seeds represent a valuable source of active compounds that may positively influence health. In this study, the pea globulins were digested in vitro under gastrointestinal condition and potentially bioaccessible angiotensin I converting enzyme (ACE) inhibitory peptides were identified. The degree of hydrolysis after pepsin, 14.42%, and pancreatin, 30.65%, were noted. The peptides with the highest ACE inhibitory properties were separated using ion exchange chromatography on DEAE-cellulose. Thirteen peptides fractions were obtained but only four showed potential antihypertensive properties. The highest inhibitory activity was determined for the fraction F8 (IC50 = 0.0014 mg/mL). This fraction was separated on Sephadex G10 and two peptide fractions were obtained. The peptides fraction (B) with the highest ACE inhibitory activity (IC50 = 0.073 mg/mL) was identified by ESI-MS/MS. The sequences of ACE inhibitory peptides were GGSGNY, DLKLP, GSSDNR, MRDLK, and HNTPSR. Based on Lineweaver-Burk plots for the fraction B, the kinetic parameters as K m, Vmax, and K i and mode of inhibition were determined. This fraction belongs to uncompetitive inhibitor of ACE activity. The seeds of pea are the source of precursor protein, which releases the ACE inhibitory peptides as a result of enzymatic hydrolysis.
豌豆种子是活性化合物的宝贵来源，可能对健康产生积极影响。在本研究中，豌豆球蛋白在体外胃肠道条件下进行消化，并鉴定出具有潜在生物可利用性的血管紧张素I转换酶（ACE）抑制肽。记录了胃蛋白酶消化后的水解度为14.42%，胰蛋白酶消化后的水解度为30.65%。使用DEAE-纤维素离子交换色谱法分离出具有最高ACE抑制特性的肽。获得了13个肽级分，但只有4个显示出潜在的降压特性。确定级分F8的抑制活性最高（IC50 = 0.0014 mg/mL）。该级分在Sephadex G10上分离，得到两个肽级分。通过ESI-MS/MS鉴定出具有最高ACE抑制活性（IC50 = 0.073 mg/mL）的肽级分（B）。ACE抑制肽的序列为GGSGNY、DLKLP、GSSDNR、MRDLK和HNTPSR。基于级分B的Lineweaver-Burk图，确定了动力学参数Km、Vmax和Ki以及抑制模式。该级分属于ACE活性的非竞争性抑制剂。豌豆种子是前体蛋白的来源，该前体蛋白通过酶水解释放出ACE抑制肽。
