Quinoa is a pseudo-cereal that is rich in protein and an ideal source of antihypertensive peptides. In this study, quinoa flour was fermented using Lactobacillus paracasei CICC 20241 via a solid fermentation to produce antihypertensive peptides. The peptides were isolated and purified by ultrafiltration and gel chromatography, then identified by liquid chromatography-tandem mass spectrometry. In addition, potential angiotensin converting enzyme (ACE) inhibitory peptides were synthesized referring to in silico analysis. Ninety-one peptides were identified, of which five were synthesized. Among these, NIFRPFAPEL and AALEAPRILNL had the greatest inhibitory effect, with an IC50 of 49.02 µM and 79.72 µM, respectively. Inhibition dynamics and molecular docking indicated that NIFRPFAPEL formed eight hydrogen bonds with ACE residues Tyr523, Arg522, Glu384, Glu143, Glu123, Thr92, Tyr62, and Trp59. NIFRPFAPEL exerted a competitive inhibitory effect by interacting with residues Tyr523 and Glu384 of pocket S1. AALEAPRILNL exerted a non-competitive inhibitory effect by forming eight hydrogen bonds with the inactive ACE site residues Ser516, Glu403, Ser355, Glu143, ARG124, and Asn70. These results confirmed that quinoa is a potential material for antihypertensive functional foods, while NIFRPFAPEL and AALEAPRILNL could be used for the development of antihypertensive functional foods or drugs
