Antihypertensive peptide IAPG

• COA/MS/HPLC Report
• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

The peptide IAPG is a bioactive tetrapeptide with demonstrated angiotensin I-converting enzyme (ACE) inhibitory activity, originally identified from the microalga Spirulina platensis. It exhibits an IC₅₀ value of 11.40 μM, indicating its potency as an ACE inhibitor. Structurally, IAPG consists of the amino acid sequence Isoleucine-Alanine-Proline-Glycine, which contributes to its interaction with the active site of ACE, a zinc metallopeptidase involved in the renin-angiotensin system.

In a recombinant expression system using Pichia pastoris, IAPG was produced as part of a fusion polypeptide alongside other ACE-inhibitory peptides. Following purification and enzymatic digestion, IAPG was released and confirmed via reverse-phase HPLC. Its ACE-inhibitory mechanism involves competitive binding to the enzyme, reducing the conversion of angiotensin I to angiotensin II, a key vasoconstrictor. The peptide's stability and activity were further validated after pepsin hydrolysis, highlighting its potential as a functional bioactive peptide.

• Suetsuna K, Chen JR. Identification of antihypertensive peptides from peptic digest of two microalgae, Chlorella vulgaris and Spirulina platensis. Mar Biotechnol. 2001;3(4):305-9.
• Tai HM, Li CC, Hung CY, Yin LJ. Production of functional peptides with inhibition ability against angiotensin I-Converting enzyme using P. pastoris expression system. J Food Drug Anal. 2018 Jul;26(3):1097-1104. doi: 10.1016/j.jfda.2018.02.001. Epub 2018 Feb 21. PMID: 29976402; PMCID: PMC9303040.

Trifluoroacetic acid (TFA) is a common counterion from the purification process using High-Performance Liquid Chromatography (HPLC). The presence of TFA can affect the peptide's net weight, appearance, and solubility.

Impact on Net Weight: The TFA salt contributes to the total mass of the product. In most cases, the peptide content constitutes >80% of the total weight, with TFA accounting for the remainder.

Solubility: TFA salts generally enhance the solubility of peptides in aqueous solutions.

In Biological Assays: For most standard in vitro assays, the residual TFA levels do not cause interference. However, for highly sensitive cellular or biochemical studies, please be aware of its presence.