In this study, the inhibitory effect of Temporin-Ra (FP-14 peptide) on angiotensin converting enzyme(ACE) was evaluated. Inhibition mechanism was investi-gated by kinetic studies and molecular docking simulation.Lineweaver–Burk plot revealed that Temporin-Ra behavedas a non-competitive ACE inhibitor supported by the dock-ing simulation. The IC50 and Ki values were determined to be22.19 lM and 36 lg/ml, respectively. Molecular dockingsimulation showed that Temporin-Ra bound to both of N-and C-domains of ACE by forming hydrogen bonds andelectrostatic interactions; Temporin-Ra displayed higheraffinity to C-domain than N-domain. Antioxidant activity ofTemporin-Ra was examined using different methods. Theantioxidant activity of Temporin-Ra (0.2 mg/ml) in theinhibition of linoleic acid autoxidation was evaluated to be57 %. 1,1-diphenyl-2-picrylhydrazyl and 2, 2-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) diammonium saltradicals scavenging activities were 60 % at 0.5 mg/ml and37 % at 0.3 mg/ml, respectively. The hydroxyl radicalscavenging of FP-14 peptide at 0.33 mg/ml was 55 %. Theresults suggest that Temporin-Ra is a multifunctional peptidethat could be exploited to develop new anti-hypertensiondrugs and bio-compatible natural antioxidants.

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