Actis-Goretta Lucas, Ottaviani Javier I, Keen Carl L, Fraga Cesar G
Physical Chemistry-PRALIB, School of Pharmacy and Biochemistry, University of Buenos Aires, Juni;n 956, 1113, Buenos Aires, Argentina.
FEBS Lett. 2003 Dec 18;555(3):597-600. doi: 10.1016/s0014-5793(03)01355-3.
It was determined that flavan-3-ols and procyanidins have an inhibitory effect on angiotensin I converting enzyme (ACE) activity, and the effect was dependent on the number of epicatechin units forming the procyanidin. The inhibition by flavan-3-ols and procyanidins was competitive with the two substrates assayed: N-hippuryl-L-histidyl-L-leucine (HHL) and N-[3-(2-furyl)acryloyl]-L-phenylalanylglycylglycine (FAPGG). Tetramer and hexamer fractions were the more potent inhibitors, showing Ki of 5.6 and 4.7 microM, respectively. As ACE is a membrane protein, the interaction of flavanols and procyanidins with the enzyme could be related to the number of hydroxyl groups on the procyanidins, which determine their capacity to be adsorbed on the membrane surface.
已确定黄烷-3-醇和原花青素对血管紧张素I转换酶（ACE）活性具有抑制作用，且该作用取决于构成原花青素的表儿茶素单元数量。黄烷-3-醇和原花青素的抑制作用与所检测的两种底物竞争：N-马尿酰-L-组氨酰-L-亮氨酸（HHL）和N-[3-(2-呋喃基)丙烯酰]-L-苯丙氨酰甘氨酰甘氨酸（FAPGG）。四聚体和六聚体部分是更强效的抑制剂，其抑制常数（Ki）分别为5.6和4.7微摩尔。由于ACE是一种膜蛋白，黄烷醇和原花青素与该酶的相互作用可能与原花青素上的羟基数量有关，这些羟基决定了它们吸附在膜表面的能力。
