Separation of angiotensin I‐converting enzyme inhibitory peptides from bovine connective tissue and their stability towards temperature, pH and digestive enzymes

Abstract

Bovine collagen was isolated from connective tissue, a by-product in the meat processing industry and characterised by SDS-PAGE. Alcalase and papain were employed to generate collagen hydrolysates with different degree of hydrolysis (DH). In vitro angiotensin I-converting enzyme (ACE) inhibitory activities were evaluated and the two most potent hydrolysates from each enzyme were separated by two-step purification. Both alcalase-catalysed and papain-catalysed hydrolysates exhibited strong ACE inhibitory capacities with IC 50 values of 0.17 and 0.35 mg mL À1 , respectively. Purification by ion-exchange chromatography and gel filtration chromatography revealed higher ACE inhibitory activities in one fraction from each enzyme with IC 50 values of 3.95 and 7.29 lg mL À1 . These peptide fractions were characterised as 6-12 amino acid residues by MALDI-TOF/MS. The peptides retained their activity (>90%) after exposure to processing temperature and pH and in vitro simulated gastrointestinal digestion. The present results demonstrated that collagen peptides can be utilised for developing high value-added ingredients, for example ACE inhibitory peptides.

Effects of heat and pH treatments and in vitro digestion on the biological activity of protein hydrolysates of Amaranthus hypochondriacus L. grain

“…The impact of pH (2.0-10.0) on the ACEIA of collagen hydrolysates afforded a significant reduction of ACEIA at strong alkaline conditions (pH 10.0). Similarly, in agreement with our research, collagen peptides exhibited good resistance against the acidic and weak alkaline conditions and heat treatment (Fu et al 2015).…”

“…Thus, the collagen peptides may endure digestion considerably through the gastrointestinal tract or they may be partially degraded into smaller peptides whilst retaining their activity. Collagen peptides display potent ACEIA after an in vitro digestion, possibly due to posttranslational hydroxylation of proline in collagen (Fu et al 2015).…”

“…Similarly, Wu and Ding (2002) observed that soy-protein-derived peptides with ACEIA also displayed stability at 100°C for 30 min. Fu et al (2015) studied the effect of different temperatures on the ACEIA of collagen and found that this kept its inhibitory capacity at relatively low temperatures (20-60°C). Conversely, after heating for 2 h at 100°C, they noted a slight reduction of the inhibitory activity.…”

Isolation and Purification of Antioxidant and ACE-Inhibitory Peptides from Yak (Bos grunniens ) Skin

“…Yak (Bos grunniens) is a kind of cattle which can survive on Tibetan plateau due to their tenacious vitality and adaption to cold climates and low oxygen pressure. In previous study, bovine collagen showed excellent ACE inhibitory activity with IC 50 of 3.95 and 7.29 lg mL 21 (Fu et al 2015). As yak live in a pollution-free environment, and mainly grow naturally without manual feed, it is safer and healthier to obtain valuable products such as meat, skin, milk and horn from them.…”

Bioactive peptides derived from bovine and porcine co-products: A review

“…Although the hydrolysates and the control (captopril, an antihypertensive drug) were fed at different concentrations, both showed a similar trend in lowering the SBP of SHRs. Fu, Young, Dalsgaard, and Therkildsen () recently generated enzymatic hydrolysates from bovine connective tissue using Alcalase and papain and different degrees of hydrolysis. The two most potent hydrolysates showed IC 50 values of 0.17 and 0.35 mg/mL for Alcalase and papain, respectively.…”