Two novel ACE inhibitory peptides isolated from longan seeds: purification, inhibitory kinetics and mechanisms
Atthasith Nuchprapha, Supawee Paisansak, Papassara Sangtanoo, Piroonporn Srimongkol, Tanatorn Saisavoey, Onrapak Reamtong, Kiattawee Choowongkomon, Aphichart Karnchanatat
Abstract
), which was shown to be Glu-Thr-Ser-Gly-Met-Lys-Pro-Thr-Glu-Leu (ETSGMKPTEL) and Ile-Ser-Ser-Met-Gly-Ile-Leu-Val-Cys-Leu (ISSMGILVCL). These two peptides were stable over a temperature and pH range of -20 to 90 °C and 2-12, respectively, for 60 min. From the Lineweaver-Burk plot, both peptides inhibited ACE non-competitively. Molecular docking simulation of the peptides with ACE supported the formation of hydrogen bonds by the peptides with the ACE active pockets. This research indicates that it may be possible to use both of these peptides or longan seed protein hydrolysates in order to create ingredients for functional foods, or to produce pharmaceutical products, capable of lowering hypertension.