Casein-Derived Tripeptide LLY Potently Blocks ACE Through Multiple Binding Interactions | Research

The takeaway

The casein-derived tripeptide LLY (Leu-Leu-Tyr) showed high ACE-inhibitory activity and stability, with detailed molecular studies revealing multiple binding interactions at the enzyme's active site.

High ACE inhibition + stability
Casein tripeptide LLY combines potent enzyme blocking with structural stability — key requirements for a viable functional food ingredient

What the researchers found

The casein-derived tripeptide LLY demonstrated high ACE-inhibitory activity with excellent stability. Systematic investigation revealed the molecular details of LLY-ACE binding interactions important for understanding and designing antihypertensive peptides.

Why it matters

Milk-derived ACE-inhibitory peptides are among the most studied food-derived bioactives. Detailed molecular mapping of how LLY binds ACE advances both the science of food-derived antihypertensives and the rational design of more potent peptide candidates.

The numbers in context

LLY (Leu-Leu-Tyr) showed high ACE inhibitory activity with specific binding interactions characterized at the molecular level.

How the study worked

ACE-inhibitory peptide LLY isolated from casein hydrolysate. ACE-inhibitory activity and stability tested. LLY-ACE interaction characterized through systematic molecular investigation techniques.

Who was studied

ACE enzyme interaction studies

What this study cannot tell us

In vitro study — ACE inhibition in a test tube doesn't guarantee blood pressure lowering in humans. The specific IC50 value wasn't reported in the available abstract. Bioavailability after actual dairy consumption is unknown.

How to read the evidence

Preliminary evidence from in vitro enzyme assays and molecular interaction studies. No in vivo or clinical validation.

When this study was published

Published in 2024; represents current research in milk-derived ACE-inhibitory peptide characterization.

The bigger picture

Casein-derived peptides like VPP and IPP have already been commercialized in functional foods (Calpis, Evolus). LLY adds to the growing library of validated milk peptides with ACE-inhibitory activity, and the detailed binding data could guide development of next-generation dairy-based antihypertensive products.

Questions still open

How does LLY's ACE-inhibitory potency compare to the commercialized casein peptides VPP and IPP?
Can LLY survive gastrointestinal digestion and reach the bloodstream at active concentrations?
Would LLY-enriched dairy products lower blood pressure in human clinical trials?

Common questions

Does drinking milk lower blood pressure?

Some studies suggest regular dairy consumption is associated with modest blood pressure benefits. This study identifies a specific peptide (LLY) from milk protein that blocks the blood-pressure-raising enzyme ACE. However, whether enough LLY is released during normal dairy digestion to meaningfully affect blood pressure hasn't been determined.

How is this different from other milk peptides like VPP and IPP?

VPP and IPP are well-known casein-derived ACE inhibitors already used in commercial products. LLY is a different peptide sequence (Leu-Leu-Tyr) with its own unique binding profile at the ACE active site. This study adds it to the growing catalog of validated dairy antihypertensive peptides.

Read the original research

Investigation of the Interaction Between Angiotensin-Converting Enzyme (ACE) and ACE-Inhibitory Tripeptide from Casein.

International journal of molecular sciences, 25(23)

View on PubMed ↗Publisher’s paper ↗

Citation

Yang, Cuicui; Xie, Tianzhao; Cai, Mengmeng; Xu, Xiaoting; Li, Muzijun; Liu, Pengru; Lan, Xiongdiao. (2024). Investigation of the Interaction Between Angiotensin-Converting Enzyme (ACE) and ACE-Inhibitory Tripeptide from Casein.. International journal of molecular sciences, 25(23). https://doi.org/10.3390/ijms252313021