Structural analysis of a new anti-hypertensive peptide (beta-lactosin B) isolated from a commercial whey product

J Dairy Sci. 2004 Jul;87(7):1967-74. doi: 10.3168/jds.S0022-0302(04)70013-2.

Abstract

Angiotensin-converting enzyme (ACE) inhibitory activities and anti-hypertensive activities in spontaneously hypertensive rats (SHR) of 12 kinds of commercial peptides of food additive grade were measured. Four peptide products derived from milk proteins showed strong anti-hypertensive activities (>-18.0 mm Hg). A sample of WE80BG derived from whey proteins showed the strongest anti-hypertensive activity (-21.2 +/- 16.9 mm Hg) with a medium level of ACE inhibitory activity (53.6%), and it was subjected to hydrophobic and gel filtration chromatography. From the low molecular weight fraction, an anti-hypertensive peptide was isolated by using reversed-phase HPLC, and it was found to be a tetrapeptide, alanine-leucine-proline-methionine (Ala-Leu-Pro-Met, ALPM), the origin of which was estimated to be beta-lactoglobulin f 142 to 145. At 8 h after oral administration of ALPM in SHR, systolic blood pressure was significantly decreased (-21.4 +/- 7.8 mm Hg), but the IC50 value (concentration of peptide needed to inhibit 50% of the ACE activity) of ALPM was not so high. We named the Ala-Leu-Pro-Met "beta-lactosin B." This peptide is the second anti-hypertensive peptide found from beta-lactoglobulin. Because WE80BG containing ALPM was also found to show the strongest anti-hypertensive activity (-24.5 +/- 10 mm Hg) at 8 h after oral administration in SHR, WE80BG would be suitable for application to the development of a new food expected to have anti-hypertensive effects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / analysis
  • Angiotensin-Converting Enzyme Inhibitors / chemistry
  • Angiotensin-Converting Enzyme Inhibitors / isolation & purification
  • Angiotensin-Converting Enzyme Inhibitors / pharmacology
  • Animals
  • Antihypertensive Agents / chemistry*
  • Antihypertensive Agents / isolation & purification
  • Antihypertensive Agents / pharmacology
  • Blood Pressure
  • Chromatography, High Pressure Liquid
  • Kinetics
  • Lactoglobulins / chemistry*
  • Lactoglobulins / isolation & purification
  • Lactoglobulins / pharmacology
  • Male
  • Milk Proteins / chemistry*
  • Peptide Fragments / chemistry*
  • Peptide Fragments / isolation & purification
  • Peptide Fragments / pharmacology
  • Peptides / chemistry
  • Peptides / isolation & purification
  • Peptides / pharmacology
  • Rats
  • Rats, Inbred SHR
  • Rats, Wistar
  • Whey Proteins

Substances

  • Ala-Leu-Pro-Met
  • Amino Acids
  • Angiotensin-Converting Enzyme Inhibitors
  • Antihypertensive Agents
  • Lactoglobulins
  • Milk Proteins
  • Peptide Fragments
  • Peptides
  • Whey Proteins