Purification, Identification, and In Vivo Activity of Angiotensin I‐Converting Enzyme Inhibitory Peptide, from Ribbonfish (Trichiurus haumela) Backbone

Abstract

Ribbonfish (Trichiurus haumela) backbone is normally discarded as an industrial waste from fish processing. A method of developing angiotensin I-converting enzyme inhibitory (ACEI) peptides from ribbonfish backbone was previously optimized. The purposes of the study were to characterize the active peptides in the hydrolysate and to evaluate its in vivo activity. Ribbonfish backbone protein hydrolysate prepared by acid protease was fractionated into 4 fractions (I, MW < 1 kDa; II, MW = 1 to 5 kDa; III, MW = 5 to 10 kDa; and IV, MW > 10 kDa) through ultrafiltration membranes. Fraction I, showing the highest ACEI activity, was further purified using consecutive chromatographic techniques including gel filtration and reversed phase high-performance liquid chromatography. The purified ACE inhibitory peptide was determined to have a molecular weight of 317.25 Da, with a sequence of Leu-Trp and an IC₅₀ value of 5.6 μM. Systolic blood pressure of spontaneously hypertensive rats was significantly decreased from 181 ± 2.0 to 161.3 ± 2.3 mm Hg after 4 h of oral administration of Leu-Trp at a dose of 10 mg/kg of body weight. These results indicated that ribbonfish backbone protein could be used for development of antihypertensive agent.

Peptides: Production, bioactivity, functionality, and applications

“…Generally, fractions containing low-molecular weight peptides have been reported to exhibit higher bioactivities in vitro. For instance, numerous studies indicate that peptide fractions <1 kDa showed the strongest Angiotensin-I converting enzyme (ACE)-inhibitory activity, independently of the type of raw protein (e.g., terrestrial plants or fish) (Zhao et al, 2007;Zou et al, 2014;Wu et al, 2016a, b). Nevertheless, these differences on ACE-inhibitory activity depending on the molecular weight of the peptides might not be observed in vivo as reported for salmon protein hydrolysate fractions (Ewart et al, 2009).…”

Efficacy of a Novel ACE-Inhibitory Peptide from Sargassum maclurei in Hypertension and Reduction of Intracellular Endothelin-1

“…Meanwhile, rats in the positive control were orally given captopril (14 mg/kg/body weight once daily), and rats in the negative control were just administrated saline (0.9%). The diastolic blood pressure (DBP) and systolic blood pressure (SBP) of the rats were measured by the tail-cuff method once a week [33]. The heart rate was recorded simultaneously.…”

Isolation of Novel ACE-Inhibitory and Antioxidant Peptides from Quinoa Bran Albumin Assisted with an In Silico Approach: Characterization, In Vivo Antihypertension, and Molecular Docking

“…Following the method indicated by Zou et al [26] with some modifications, 20 male SHRs (10 weeks, 230 ± 20 g body weight (bw)) were purchased from Vital River Laboratory Animal Technology Co., Ltd (Beijing, China). After conditioning for one week, the rats were divided into five groups of four rats each.…”