ACE-inhibitory Peptides Research Articles

Purification of angiotensin converting enzyme inhibitory peptides and antihypertensive effect generated from Indonesian traditional fermented beef (Cangkuk).

Traditional fermented meat products can be considered a source of bioactive peptides. Cangkuk, a traditional Indonesian fermented beef product is one source of angiotensin converting enzyme (ACE) inhibitory peptides. This study aimed to identify ACE-inhibitory peptides from Cangkuk and analyze their antihypertensive effects. The water-soluble fraction of Cangkuk was fractionated to obtain ACE-inhibitory peptides using an ethanol solvent at several concentrations and solid-phase extraction with an OASIS HLB cartridge followed by purification with reversed-phase high-performance liquid chromatography (RP-HPLC). HPLC-MS was used to identify target peptides, followed by automatic protein sequencer analysis to detect peptide sequences. Antihypertensive effects were analyzed on the water-soluble fraction and synthesized peptides. The animal model comprised 14-16-week-old male spontaneously hypertensive rats (SHRs) (~320 g average body weight) with mean systolic blood pressures (SBPs) higher than 190 mmHg. All oral doses of peptides were 1 mL in volume. Distilled water was used as a control. The antihypertensive activities of the sample and control were observed by measuring the SBP at 0, 2, 4, 6, 8 and 24 h after oral administration. Two sequences of ACE inhibitory peptides were found, EAPLNPKANR (IC50 value of 44.6 μmol/L) and IVG (IC50 value of 97.3 μmol/L). The water-soluble fraction demonstrated an antihypertensive effect on SHRs after oral administration at 100 mg/kg body weight, maximally lowering the SBP by 14.9 mmHg 8 h after administration. The tripeptide IVG showed the highest reduction of SBP, 24.76±2.1 mmHg 8 h after administration. The decapeptide EAPLNPKANR showed the highest reduction of SBP, 21.0±1.9 mmHg, 8 h after administration. All the samples differed significantly from the control (p<0.01). Cangkuk has potential as a functional food ingredient acting as an antihypertensive agent.

Screening and rational identification of a novel angiotensin-converting enzyme C-domain inhibitory peptide from Fabaceae food peptide library

Angiotensin-converting enzyme (ACE), consisting of N-domain and C-domain, is a key regulator of blood pressure. The use of cACE-specific inhibitors helps minimize side effects in clinical applications. Legumes are a good source of proteins containing ACE inhibitory peptides; however, no studies have reported the identification of cACE-specific inhibitory peptides from Fabaceae. In this study, thermal hydrolysates from seeds, sprouts, pods, seedlings, and flowers of legumes were analyzed. Flowers of legumes exhibited a C-domain-preference ACE inhibition and anti-hypertensive effect in rats. Screening the legume peptide library identified a novel cACE inhibitory peptide, SJ-1. This study reported the first identification of cACE inhibitory peptide from Fabaceae foods. SJ-1, identified from the legume flowers, interacted with active site residues of cACE, leading to the inhibition of ACE activity, downregulation of bradykinin levels, and reduction of blood pressure. These findings also suggested the potential of legume proteins as a source of cACE inhibitory peptides.

ACE-inhibitory peptides in sodium-reduced cheese with probiotic: Identification, in silico prediction and molecular interaction

The dual effect of Lacticaseibacillus paracasei M3 and the partial substitution of NaCl on the release of ACE-inhibitory peptides in sodium-reduced cheese was investigated. The peptide profile was improved and the release of ACE inhibitory peptides was promoted by the addition of KCl and Lb.paracasei M3. Using in silico screening, novel ACE-inhibitory peptides were selected in order to predict their physicochemical characteristics. The peptides, KPWIQPK and VYPFPGPIPN, could remain intact in the gastrointestinal tract. Molecular docking results suggested that the peptides APFPEVFGK, KPWIQPK might interact with Tyr523 and Ala354 in the S1 active pocket of ACE. EPVLGPVRGPFP, VAPFPEVFGKE and VYPFPGPIPN were coordinated with Zn ions. The results suggested that sodium-reduced cheeses with added Lb.paracasei M3 could serve as potential functional foods with antihypertensive effects.

STUDY OF ANGIOTENSIN-I CONVERTING ENZYME INHIBITORY PEPTIDES DERIVED FROM Ficus pumila var. awkeotsang SEEDS HYDROLYSATE

Hypertension also known as high blood pressure that has associated with multi-metabolic pathways such as the renin-angiotensin-aldosterone system (RAAS). There have been several synthetic ACE inhibitory drugs used clinically as therapeutics for hypertension. However, synthetic drugs showed side effects on human health after long-term use. Therefore, alternative natural ACE inhibitors from food-derived are necessary to develop. The study aimed to examine the activity of angiotensin-I converting enzyme inhibitory peptides derived from Ficus pumila var. awkeotsang seeds hydrolysate and to study the efficiency of enzymatic digestion. This study used four enzymes (trypsin, pepsin, thermolysin, and chymotrypsin) to release bioactive peptides from Ficus pumila var. awkeotsang seeds that could exhibit an antihypertensive effect. The results showed that Ficus pumila var. awkeotsang trypsin hydrolysate has the highest ACEI activity, 90.37%, and the IC50 reached 169±3.5 µg/mL. Then, the hydrolysate produced by trypsin has the highest degree of hydrolysis, 4%, after 8 hours of incubation. Hence, Ficus pumila var. awkeotsang seeds hydrolysate could develop as an alternative natural product that is responsible for ACE-inhibitory activity.

Interaction mechanisms of ACE inhibitory peptides: molecular docking and molecular dynamics simulation studies on five wheat gluten derived peptides

Interaction mechanisms of ACE inhibitory peptides: molecular docking and molecular dynamics simulation studies on five wheat gluten derived peptides

Preparation, identification, and molecular docking of novel angiotensin-converting enzyme inhibitory peptides derived from rice-based distillers' spent cakes.

Rice-based distillers' spent cake (RDSC), a by-product of the Chinese liquor (Baijiu) industry, is a potential source of angiotensin-converting enzyme (ACE) inhibitory peptide. Since ACE plays a crucial role in controlling hypertension, inhibition of ACE has been widely emphasized. The ACE inhibitory active peptide derived from by-products of food has been recognized as a safer and cheaper inhibitor. Aimed to discover ACE-inhibiting active peptides in RDSC. Hydrolysis of RDSC by alcalase for 4 h followed by ultrafiltration yielded low-molecular-weight (< 3 kDa) fractions. Subsequently, a comprehensive method using a combination of liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) and LC-Q-Exactive-MS to identify the novel short peptides (3-5 amino acids residues; n = 7) and medium-sized peptides (more than 6 amino acids residues; n = 6). In vitro activity assay showed that the peptides KPFFPGL, GFPRPLL, GPPGVF, and VGK exhibited the highest activity with inhibitory concentration of 50% (IC50) of 11.63, 12.34, 19.55, and 33.54 μmol L-1. Molecular docking reveal that the active and inactive sites (Glu123, Asp121, Arg522, and Lys118) play important roles in enhancing the ACE inhibitory activity of peptides. Here we report a comprehensive method that effectively extracted and identified the bioactive peptides from RDSC. Four highly active novel peptides may be the most promising candidates for functional foods against hypertension, provide significant information for enhancing value of rice-based distilled by-products. © 2024 Society of Chemical Industry.

Optimization of Extraction Process and Activity of Angiotensin-Converting Enzyme (ACE) Inhibitory Peptide from Walnut Meal.

In order to further realize the resource reuse of walnut meal after oil extraction, walnut meal was used as raw material to prepare polypeptide, and its angiotensin-converting enzyme (ACE) inhibitory activity was investigated. The ACE inhibitory peptides were prepared from walnut meal protein by alkaline solution and acid precipitation. The hydrolysis degree and ACE inhibition rate were used as indexes to optimize the preparation process by single-factor experiment and response surface method. The components with the highest ACE activity were screened by ultrafiltration, and their antioxidant activities were evaluated in vitro. The effect of gastrointestinal digestion on the stability of walnut peptide was analyzed by measuring molecular weight and ACE inhibition rate. The results showed that the optimal extraction conditions were pH 9.10, hydrolysis temperature 54.50 °C, and hydrolysis time 136 min. The ACE inhibition rate of walnut meal hydrolysate (WMH) prepared under these conditions was 63.93% ± 0.43%. Under the above conditions, the fraction less than 3 kDa showed the highest ACE inhibitory activity among the ACE inhibitory peptides separated by ultrafiltration. The IC50 value of scavenging ·OH free radical was 1.156 mg/mL, the IC50 value of scavenging DPPH free radical was 0.25 mg/mL, and the IC50 value of scavenging O2- was 3.026 mg/mL, showing a strong total reducing ability. After simulated gastrointestinal digestion in vitro, the ACE inhibitory rate of walnut peptide decreased significantly, but it still maintained over 90% ACE inhibitory activity. This study provides a reference for the application of low-molecular-weight walnut peptide as a potential antioxidant and ACE inhibitor.

A novel angiotensin I-converting enzyme inhibitory peptide from walnut (Juglans sigillata) protein hydrolysates and its evaluation in Ang II-induced HUVECs and hypertensive rats

This study aims to seek angiotensin-I-converting enzyme inhibitory (ACEi) peptides from walnut using different enzymatic hydrolysis, and further to validate the potent ACEi peptides identified and screened via peptidomics and in silico analysis against hypertension in spontaneously hypertensive rats (SHRs). Results showed that walnut protein hydrolysate (WPH) prepared by combination of alcalase and simulated gastrointestinal digestion exhibited high ACEi activity. WPH was separated via Sephadex-G25, and four peptides were identified, screened and verified based on their PeptideRanker score, structural characteristic and ACE inhibition. Interestingly, FDWLR showed the highest ACEi activity with IC50 value of 8.02 μg/mL, which might be related to its close affinity with ACE observed in molecular docking. Subsequently, high absorption and non-toxicity of FDWLR was predicted via in silico absorption, distribution, metabolism, excretion and toxicity. Furthermore, FDWLR exhibited positively vasoregulation in Ang II-induced human umbilical vein endothelial cells, and great blood pressure lowering effect in SHRs.

Research on the screening and inhibition mechanism of angiotensin I-converting enzyme (ACE) inhibitory peptides from tuna dark muscle

The rapid screening of angiotensin I-converting enzyme (ACE) inhibitory peptides (ACEIPs) from protein hydrolysates remains a challenge in current researches. The current study presents the development of an efficient affinity medium (AOPAN–ACE) consisting of ACE immobilized on the surface of electrostatically spun polyacrylonitrile nanofibrous membranes for the efficient screening of ACEIPs. The application of this affinity medium followed by liquid chromatography–tandem mass spectrometry analysis resulted in the successful screening and identification of 60 potential ACEIPs from protein hydrolysates of tuna dark muscle. Notably, the application of PeptideRanker, pLM4ACE, and molecular docking approaches resulted in the screening and identification of a novel ACEIP FPPDVA. Furthermore, the peptide FPPDVA was synthesized using the solid-phase method, and its IC50 value on ACE was determined to be 87.11 ± 1.02 μM. Molecular docking analysis suggested that the ACEIP of the peptide FPPDVA is attributable to the formation of hydrogen bonds with the S1 active site (Ala354 and Tyr523) of ACE and metal–ligand bonds with Zn2+. In addition, molecular dynamics simulations revealed that the peptide FPPDVA formed a stable complex with ACE and was consistently localized within the active pocket of ACE over a simulation duration of 100 ns without being displaced from the active site. Lineweaver–Burk analysis further confirmed that the peptide FPPDVA exhibited mixed mode of inhibition against ACE. Overall, the affinity medium developed in the current study is potentially useful for highly efficient screening of ACEIPs, and the novel ACEIP FPPDVA identified herein is a promising functional food ingredient for antihypertensive application.

Retracted: Exploration of ACE-Inhibiting Peptides Encrypted in Artemisia annua Using In Silico Approach.

[This retracts the article DOI: 10.1155/2022/5367125.].

Biodirected Screening and Preparation of Larimichthys crocea Angiotensin-I-Converting Enzyme-Inhibitory Peptides by a Combined In Vitro and In Silico Approach.

Food-derived angiotensin-I-converting enzyme (ACE)-inhibitory peptides have gained attention for their potent and safe treatment of hypertensive disorders. However, there are some limitations of conventional methods for preparing ACE-inhibitory peptides. In this study, in silico hydrolysis, the quantitative structure-activity relationship (QSAR) model, LC-MS/MS, inhibition kinetics, and molecular docking were used to investigate the stability, hydrolyzability, in vitro activity, and inhibition mechanism of bioactive peptides during the actual hydrolysis process. Six novel ACE-inhibitory peptides were screened from the Larimichthys crocea protein (LCP) and had low IC50 values (from 0.63 ± 0.09 µM to 10.26 ± 0.21 µM), which were close to the results of the QSAR model. After in vitro gastrointestinal simulated digestion activity of IPYADFK, FYEPFM and NWPWMK were found to remain almost unchanged, whereas LYDHLGK, INEMLDTK, and IHFGTTGK were affected by gastrointestinal digestion. Meanwhile, the inhibition kinetics and molecular docking results were consistent in that ACE-inhibitory peptides of different inhibition forms could effectively bind to the active or non-central active centers of ACE through hydrogen bonding. Our proposed method has better reproducibility, accuracy, and higher directivity than previous methods. This study can provide new approaches for the deep processing, identification, and preparation of Larimichthys crocea.

The novel angiotensin-I-converting enzyme inhibitory peptides from Scomber japonicus muscle protein hydrolysates: QSAR-based screening, molecular docking, kinetic and stability studies

Food-derived angiotensin-converting enzyme-inhibitory (ACE-I) peptides have attracted extensive attention. Herein, the ACE-I peptides from Scomber japonicus muscle hydrolysates were screened, and their mechanisms of action and inhibition stability were explored. The quantitative structure–activity relationship (QSAR) model based on 5z-scale metrics was developed to rapidly screen for ACE-I peptides. Two novel potential ACE-I peptides (LTPFT, PLITT) were predicted through this model coupled with in silico screening, of which PLITT had the highest activity (IC50: 48.73 ± 7.59 μM). PLITT inhibited ACE activity with a mixture of non-competitive and competitive mechanisms, and this inhibition mainly contributed to the hydrogen bonding based on molecular docking study. PLITT is stable under high temperatures, pH, glucose, and NaCl. The zinc ions (Zn2+) and copper ions (Cu2+) enhanced ACE-I activity. The study suggests that the QSAR model is effective in rapidly screening for ACE-I inhibitors, and PLITT can be supplemented in foods to lower blood pressure.

Antihypertensive effects of condiments prepared from fermented legumes: A review

The prevalence of hypertension has been increasing over the years. Thus, dietary guidelines focusing on the reduction of daily sodium intake are introduced. The association between the intake of condiments, one of the major sources of dietary sodium, and the prevalence of hypertension has been investigated. Regardless of high sodium content, condiments prepared from fermented legumes exert antihypertensive effects instead of increasing the risk of hypertension. Considering the hypotensive potency of legume-based condiments, modifications including reduction or removal of sodium content, incorporation of high protein fermentation substrate, changing of fermentation conditions, and selection of different microbial strains have been carried out to enhance their antihypertensive effects. The elevated antihypertensive activity of legume-based condiments is mainly associated with the increment of angiotensin-converting enzyme (ACE) inhibitory peptides formed during fermentation. The precise mechanisms of legume-based condiments in regulating blood pressure are complex and yet to be validated. Considering the antihypertensive potential of legume-based condiments, the present review paper aimed to summarise and elaborate their antihypertensive effects.

Novel Multitarget ACE Inhibitory Peptides from Bovine Colostrum Immunoglobulin G: Cellular Transport, Efficacy in Regulating Endothelial Dysfunction, and Network Pharmacology Studies.

In this study, we used traditional laboratory methods, bioinformatics, and cellular models to screen novel ACE inhibitory (ACEI) peptides with strong ACEI activity, moderate absorption rates, and multiple targets from bovine colostrum immunoglobulin G (IgG). The purified fraction of the compound proteinase hydrolysate of IgG showed good ACEI activity. After nano-UPLC-MS/MS identification and in silico analysis, eight peptides were synthesized and verified. Among them, SFYPDY, TSFYPDY, FSWF, WYQQVPGSGL, and GVHTFP were identified as ACEI peptides, as they exhibited strong ACEI activity (with IC50 values of 104.7, 80.0, 121.2, 39.8, and 86.3 μM, respectively). They displayed good stability in an in vitro simulated gastrointestinal digestion assay. In a Caco-2 monolayer model, SFYPDY, FSWF, and WYQQVPGSGL exhibited better absorption rates and lower IC50 values than the other peptides and were thereby identified as novel ACEI peptides. Subsequently, in a H2O2-induced endothelial dysfunction (ED) model based on HUVECs, SFYPDY, FSWF, and WYQQVPGSGL regulated ED by reducing apoptosis and ROS accumulation while upregulating NOS3 mRNA expression. Network pharmacology analysis and RT-qPCR confirmed that they regulated multiple targets. Overall, our results suggest that SFYPDY, FSWF, and WYQQVPGSGL can serve as novel multitarget ACEI peptides.

Targeted Affinity Purification and Mechanism of Action of Angiotensin-Converting Enzyme (ACE) Inhibitory Peptides from Sea Cucumber Gonads.

Protein hydrolysates from sea cucumber (Apostichopus japonicus) gonads are rich in active materials with remarkable angiotensin-converting enzyme (ACE) inhibitory activity. Alcalase was used to hydrolyze sea cucumber gonads, and the hydrolysate was separated by the ultrafiltration membrane to produce a low-molecular-weight peptide component (less than 3 kDa) with good ACE inhibitory activity. The peptide component (less than 3 kDa) was isolated and purified using a combination method of ACE gel affinity chromatography and reverse high-performance liquid chromatography. The purified fractions were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the resulting products were filtered using structure-based virtual screening (SBVS) to obtain 20 peptides. Of those, three noncompetitive inhibitory peptides (DDQIHIF with an IC50 value of 333.5 μmol·L-1, HDWWKER with an IC50 value of 583.6 μmol·L-1, and THDWWKER with an IC50 value of 1291.8 μmol·L-1) were further investigated based on their favorable pharmacochemical properties and ACE inhibitory activity. Molecular docking studies indicated that the three peptides were entirely enclosed within the ACE protein cavity, improving the overall stability of the complex through interaction forces with the ACE active site. The total free binding energies (ΔGtotal) for DDQIHIF, HDWWKER, and THDWWKER were -21.9 Kcal·mol-1, -71.6 Kcal·mol-1, and -69.1 Kcal·mol-1, respectively. Furthermore, a short-term assay of antihypertensive activity in spontaneously hypertensive rats (SHRs) revealed that HDWWKER could significantly decrease the systolic blood pressure (SBP) of SHRs after intravenous administration. The results showed that based on the better antihypertensive activity of the peptide in SHRs, the feasibility of targeted affinity purification and computer-aided drug discovery (CADD) for the efficient screening and preparation of ACE inhibitory peptide was verified, which provided a new idea of modern drug development method for clinical use.

Identification, structural characterization, and molecular dynamic simulation of ACE inhibitory peptides in whey hydrolysates from Chinese Rushan cheese by-product

To realize the high-value utilization of Rushan cheese by-product, Rushan cheese whey was used as a raw material to prepare angiotensin-Ⅰ-converting enzyme inhibitory peptides (ACEIPs). After enzymatic hydrolysisn and ultrafiltration, the sequences of peptides were identified by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). Two novel ACE inhibitory peptides Phe-Asp-Arg-Pro-Phe-Leu (FDRPFL) and Lys-Trp-Glu-Lys-Pro-Phe (KWEKPF) were identified. Additionally, both of the peptides exhibited good water-solubility and no toxicity according to in-silico prediction. Fourier transform infrared spectroscopy results show that both FDRPFL and KWEKPF were enriched in β-turn and β-sheet structures. Lineweaver-Burk plots revealed that FDRPFL and KWEKPF exhibited non-competitive and mixed inhibition patterns, respectively. Molecular docking and MD simulation showed that hydrogen bonds and ionic bonds forces allowed FDRPFL and KWEKPF to form stable and compact complexes with ACE. In conclusion, enzymatic hydrolysis of Rushan cheese by-products yields bioactive peptides, increases the added value of whey and reduces environmental pollution.

Exploring the Potential of Bioactive Peptides: From Natural Sources to Therapeutics.

Bioactive peptides, specific protein fragments with positive health effects, are gaining traction in drug development for advantages like enhanced penetration, low toxicity, and rapid clearance. This comprehensive review navigates the intricate landscape of peptide science, covering discovery to functional characterization. Beginning with a peptidomic exploration of natural sources, the review emphasizes the search for novel peptides. Extraction approaches, including enzymatic hydrolysis, microbial fermentation, and specialized methods for disulfide-linked peptides, are extensively covered. Mass spectrometric analysis techniques for data acquisition and identification, such as liquid chromatography, capillary electrophoresis, untargeted peptide analysis, and bioinformatics, are thoroughly outlined. The exploration of peptide bioactivity incorporates various methodologies, from in vitro assays to in silico techniques, including advanced approaches like phage display and cell-based assays. The review also discusses the structure-activity relationship in the context of antimicrobial peptides (AMPs), ACE-inhibitory peptides (ACEs), and antioxidative peptides (AOPs). Concluding with key findings and future research directions, this interdisciplinary review serves as a comprehensive reference, offering a holistic understanding of peptides and their potential therapeutic applications.

Evaluation of antioxidant and ACE inhibitory peptides in rice bran protein hydrolysate using non‐targeted UHPLC‐QTOF‐IMS profiling, MALDI‐TOF‐TOF‐MS/MS, and molecular docking study

SummaryIn the present study, rice bran protein (RBP) from the PB1121 variety was hydrolysed using trypsin and subjected to non‐targeted IMS profiling to identify antioxidant and antihypertensive amino acids in the resulting RBP hydrolysates. The hydrolysate was then separated into three fractions using ultrafiltration, and each fraction was tested for antioxidant and ACE inhibitory activities. The ACE activity was assessed using the tripeptide hippuryl‐histidyl‐leucine (HHL) as a model peptide via HPLC‐DAD. The fraction with the molecular weight (&gt;3000 Da) displayed the strongest antioxidant and ACE inhibitory activity. This fraction was further divided into five fractions using gel Sephadex G‐25, and the greatest levels of antioxidant and ACE inhibitory activity were found in fraction F3B. Fraction F3B was then fractionated using HPLC, and the fraction with ACE inhibitory activity (IC50 of 43 mg mL−1) was analysed using MALDI‐TOF‐TOF mass spectrometry to determine its exact molecular mass and amino acid sequence. The amino acid sequence FMKSK (phe‐met‐lys‐ser‐lys) with a Mw of 655.376 Da was detected, and the molecular docking investigation revealed that FMKSK suppresses ACE by forming strong hydrogen bonds with the active pockets of human ACE. These findings suggest that rice bran contains bioactive peptides with antioxidant and ACE inhibitory effects, making it a promising raw material for the production of beneficial products.

Impact of Lactiplantibacillus plantarum and casein fortification on angiotensin converting enzyme inhibitory peptides in yogurt: identification and in silico analysis.

In this study, the effects of Lactiplantibacillus plantarum M11 (Lb. plantarum M11) in conjunction with sodium caseinate on the characteristics and angiotensin converting enzyme (ACE) inhibitory activity of yogurt were investigated. ACE inhibitory peptides (ACEIPs) in yogurt were identified by nano-LC-MS/MS and potential ACEIPs were predicted by in silico and molecular docking methods. The results showed that the ACE-inhibitory activity of yogurt was significantly enhanced (p < 0.05), while maintaining the quality characteristics of the yogurt. Thirteen ACEIPs in the improved yogurt (883 + M11-CS group) were identified, which were more abundant than the other yogurt groups (control 883 group, 883 + M11 group and 883-CS group). Two novel peptides with potential ACE inhibitory activity, YPFPGPIH and NILRFF, were screened. The two peptides showed PeptideRanker scores above 0.8, small molecular weight and strong hydrophobicity, and were non-toxic after prediction. Molecular docking results showed that binding energies with ACE were -9.4 kcal mol-1 and -10.7 kcal mol-1, respectively, and could bind to the active site of ACE. These results indicated that yogurt with Lb. plantarum M11 and sodium caseinate has the potential to be utilized as a functional food with antihypertensive properties. The combination of ACEIP-producing strains and casein fortification could be an effective method to promote the release of ACEIPs from yogurt.

Screening and molecular dynamics simulation of ACE inhibitory tripeptides derived from milk fermented with Lactobacillus delbrueckii QS306.

Peptides in milk fermented with Lactobacillus delbrueckii QS306 before and after ultrahigh pressure treatment were identified using proteomics. Subsequently, 16 stable tripeptides were screened out based on activity score prediction, PeptideCutter analysis, and hydrophobicity calculations. Among them, WRP, WSR, and YRP showed the best angiotensin-converting enzyme (ACE) inhibitory activity, and their semi-inhibitory concentrations were 46.707, 300.121, and 89.555 μM, respectively. WRP and WSR were competitive inhibitors, whereas YRP was non-competitive. Gastrointestinal simulation revealed that WRP and YRP had better gastrointestinal stability. The values of RMSD, ΔGbind, ΔGpol, and RSMF obtained from molecular dynamics simulation indicated that the interaction of WRP and ACE was stable. Thus, Lactobacillus delbrueckii QS306-fermented milk can serve as an important source of ACE inhibitory peptides both before and after ultrahigh pressure treatment. The strategy of in silico screening, activity evaluation, and molecular dynamics simulation adopted in this study can be applied to the large-scale screening of novel peptides with high ACE inhibitory activity.