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Preparation and Identification of ACE Inhibitory Peptides from the Marine Macroalga Ulva intestinalis
Open accessAbstract
Angiotensin I-converting enzyme (ACE) inhibitory peptides derived from seaweed represent a potential source of new antihypertensive. The aim of this study was to isolate and purify ACE inhibitory peptides (ACEIPs) from the protein hydrolysate of the marine macroalga Ulva intestinalis. U. intestinalis protein was hydrolyzed by five different proteases (trypsin, pepsin, papain, α-chymotrypsin, alcalase) to prepare peptides; compared with other hydrolysates, the trypsin hydrolysates exhibited the highest ACE inhibitory activity. The hydrolysis conditions were further optimized by response surface methodology (RSM), and the optimum conditions were as follows: pH 8.4, temperature 28.5 °C, enzyme/protein ratio (E/S) 4.0%, substrate concentration 15 mg/mL, and enzymolysis time 5.0 h. After fractionation and purification by ultrafiltration, gel exclusion chromatography and reverse-phase high-performance liquid chromatography, two novel purified ACE inhibitors with IC50 values of 219.35 μM (0.183 mg/mL) and 236.85 μM (0.179 mg/mL) were obtained. The molecular mass and amino acid sequence of the ACE inhibitory peptides were identified as Phe-Gly-Met-Pro-Leu-Asp-Arg (FGMPLDR; MW 834.41 Da) and Met-Glu-Leu-Val-Leu-Arg (MELVLR; MW 759.43 Da) by ultra-performance liquid chromatography-tandem mass spectrometry. A molecular docking study revealed that the ACE inhibitory activities of the peptides were mainly attributable to the hydrogen bond and Zn(II) interactions between the peptides and ACE. The results of this study provide a theoretical basis for the high-valued application of U. intestinalis and the development of food-derived ACE inhibitory peptides.
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“Other promising peptides have been identified from Gracilariopsis lemaneiformis, Mazzaella japonica (Rhodophyta), and Ulva intestinalis (Chlorophyta), each contributing to ACE inhibition and cardiovascular health [58–60].”
From Navigating the potential of algal peptides: health effects, market applications, and scientific challenges (2026) · cites this paper as [60]
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“5 ◦C FGMPLDR, MELVLR ACE inhibition [84]”
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“Again, trypsin produced the extract with the highest ACE inhibitory activity, and two peptides were indicated as the most active (FGMPLDR and MELVLR) [53].”
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Metadata
- Authors
- Sun, S., Xu, X., Sun, X., Zhang, X., Chen, X., & Xu, N.
- Affiliations
- Ningbo University (CN)
- Vanderbilt University Medical Center (US)
- Corresponding author
- Xu, Nianjun
- Venue
- Marine Drugs
- Publisher
- MDPI AG
- Published
- 2019-03-19
- Volume
- 17
- Issue
- 3
- Pages
- 179
- ISSN
- 1660-3397 (ISSN-L)
- PMC
- PMC6471128
- OpenAlex
- W2922600776
- Cited by
- 140
- References
- 50
- Citations by year
- 2026: 9 · 2025: 21 · 2024: 29 · 2023: 22 · 2022: 27 · 2021: 15 · 2020: 14 · 2019: 3
- FWCI
- 4.88
- Type
- journal article
- Language
- en
- Open access
- gold
- dx.doi.org
- Licence
- Locations
- Marine Drugs (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Discover Archive (Vanderbilt University) (submittedVersion, cc-by)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
- Funders
- Natural Science Foundation of Zhejiang Province (LZ17D060001)
- Ningbo International Cooperation Program (2017D10019)
- Ningbo Municipal Bureau of Science and Technology (2016C10034)
- Topics
- Life Sciences › Agricultural and Biological Sciences › Food Science › Protein Hydrolysis and Bioactive Peptides
- Life Sciences › Agricultural and Biological Sciences › Aquatic Science › Seaweed-derived Bioactive Compounds
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Biochemistry › Peptidase Inhibition and Analysis
- Keywords
- ACE inhibitory peptides, Ulva intestinalis, seaweed, protein hydrolysates, trypsin hydrolysis, enzymatic hydrolysis optimization, peptide purification, antihypertensive peptides, food-derived bioactive peptides, zinc binding
- MeSH terms
- Angiotensin-Converting Enzyme Inhibitors, Antihypertensive Agents, Drug Stability, Hydrolysis, Hypertension, Peptidyl-Dipeptidase A, Peptide Hydrolases, Peptides, Protein Hydrolysates, Seaweed, Inhibitory Concentration 50, Ulva, Enzyme Assays, Molecular Docking Simulation
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