Preparation of corn ACE inhibitory peptide-ferrous chelate by dual-frequency ultrasound and its structure and stability analyses

• Published in: Ultrasonics sonochemistry 2022-02, Vol.83, p.105937, Article 105937
• Main Authors: Qu, Wenjuan, Feng, Yiting, Xiong, Ting, Li, Yuhan, Wahia, Hafida, Ma, Haile
• Format: Article
• Language: English
• Subjects: ACE inhibition activity; Amino Acids; Corn ACE inhibitory peptides; Iron; Iron Chelating Agents - pharmacology; Peptide-ferrous chelate; Peptides - chemistry; Short Communication; Structural characteristics; Ultrasound; Zea mays
• ISSN: 1350-4177; 1873-2828; 1873-2828
• DOI: 10.1016/j.ultsonch.2022.105937

[Display omitted] •An ultrasound treated corn ACE inhibitory peptide-ferrous chelate was developed.•CP-Fe possessed ferrous content of 66.39% and ACE inhibition activity of 82.21%.•CP-Fe was formed by binding peptide amino, carbonyl and carboxyl groups with Fe2+.•CP-Fe was stable at various temperatures, pH and gastrointestinal environments. In order to improve iron chelating ability and retain the activity of functional peptide, corn peptide was chelated with iron to form corn ACE inhibitory peptide-ferrous chelate (CP-Fe) treated by dual-frequency ultrasound. Furthermore, the chelating mechanism was revealed by analyzing various structural changes, and the stability was further evaluated. Under this study condition, the iron-binding capacity of corn ACE inhibitory peptide (CP) and chelate yield reached 66.39% and 82.87%, respectively. Ultrasound-treated CP exhibited a high iron chelating ability, meanwhile, chelation reaction had no significant effect on the ACE inhibition activity (82.21%) of the peptide. CP-Fe was formed by binding the peptides amino, carbonyl and carboxyl groups with Fe2+ demonstrated by Ultra-violet spectroscopy, Fourier transform infrared characterization, X-ray diffraction, energy dispersion spectrum, zeta potential, amino acid composition and other multi-angle analyses. Moreover, ultrasound-treated CP-Fe chelate exhibited porous surface and uniform nanoparticle shape. Furthermore, ultrasound-treated CP-Fe chelate exhibited an excellent stability towards various pH (retention rate ≥ 95.47% at pH 6–10), temperatures (retention rate ≥ 85.10% at 25–70 °C), and gastrointestinal digestion (retention rate 79.18%). Overall, ultrasound-treated CP-Fe chelate possessed high iron-chelating ability, ACE inhibition activity and stability. This study provides a novel synthesis method of the iron-chelating corn ACE inhibitory peptide, which is promising to be applied as iron supplements with high efficiency, bioactivity, and stability.