A novel walnut peptide (FDWLR, IC50 8.02 μg/mL) potently inhibited ACE, protected blood vessel cells from angiotensin II damage, and significantly lowered blood pressure in spontaneously hypertensive rats.
IC50 8.02 μg/mLFDWLR from walnut protein is exceptionally potent for a food-derived ACE inhibitor, with confirmed blood pressure lowering in hypertensive rats
What the researchers found
FDWLR from walnut protein (IC50 8.02 μg/mL ACE inhibition) demonstrated triple validation: in vitro ACE blocking, HUVEC vasoprotection against angiotensin II, and in vivo blood pressure lowering in spontaneously hypertensive rats.
Why it matters
Walnuts have long been associated with heart health, but this study identifies a specific peptide responsible and proves it works through multiple validated experiments — moving beyond epidemiological associations to molecular-level evidence.
The numbers in context
Most potent peptide identified from walnut hydrolysate. Validated through in vitro ACE inhibition, HUVEC protection, and blood pressure reduction in SHR rats.
How the study worked
Walnut protein hydrolyzed by alcalase + simulated GI digestion. Peptides separated by Sephadex-G25, identified by peptidomics, screened via PeptideRanker and in silico analysis. Validated by ACE inhibition assay, molecular docking, ADMET prediction, HUVEC angiotensin II challenge, and oral administration to SHR.
Who was studied
Spontaneously hypertensive rats + HUVEC cell cultures
What this study cannot tell us
Animal study using spontaneously hypertensive rats. The human dose needed for blood pressure effects is unknown. In silico ADMET predictions need confirmation with actual pharmacokinetic studies. Long-term safety data is lacking.
How to read the evidence
Moderate evidence combining in vitro ACE inhibition, computational analysis, cell culture validation, and in vivo animal testing. Human clinical trials have not been conducted.
When this study was published
Published in 2024; represents current food-derived antihypertensive peptide research.
The bigger picture
This adds walnuts to the growing list of foods (alongside milk, garlic, fish, and soy) with identified, validated ACE-inhibitory peptides. The comprehensive characterization of FDWLR — from discovery through in vivo validation — provides a template for functional food peptide development.
Questions still open
- How much walnut consumption would be needed to deliver a meaningful dose of FDWLR?
- Does FDWLR survive actual human digestion as predicted by the simulation?
- Would FDWLR be effective in human patients with essential hypertension?
Common questions
Are walnuts good for blood pressure?
Can I get this peptide from eating walnuts?
Read the original research
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.
International journal of biological macromolecules, 266(Pt 2), 131152
Citation
Xie, Jinxiang; Chen, Shupeng; Huan, Pengtao; Wang, Shuguang; Zhuang, Yongliang. (2024). 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.. International journal of biological macromolecules, 266(Pt 2), 131152. https://doi.org/10.1016/j.ijbiomac.2024.131152