Isolation, identification, molecular docking analysis, and cytoprotection of seven novel angiotensin I-converting enzyme inhibitory peptides from miiuy croaker byproducts-swim bladders

Abstract

For efficiently utilizing the processing byproducts of miiuy croaker to prepare novel angiotensin I-converting enzyme (ACE) inhibitory (ACEi) peptides, in vitro gastrointestinal (GI) digestion method was screened and employed to prepare swim bladder hydrolysate with the highest ACEi activity. Subsequently, seven novel ACEi peptides were isolated from the hydrolysate and identified as DEGPE, EVGIQ, SHGEY, GPWGPA, GPFGTD, SPYGF, and VIGPF with molecular weights of 545.49, 544.58, 591.55, 583.63, 592.59, 569.60, and 531.63 Da, respectively. SHGEY and SPYGF exhibited remarkable ACEi activity with IC50 values of 0.86 ± 0.12 and 0.37 ± 0.06 mg/mL. Molecular docking experiment illustrated that the significant ACEi activity of SHGEY and SPYGF with the affinity of -8.7 and -9.7 kcal/mol mainly attributed to effectively combining with the ACEi active sites by hydrophobic interaction, electrostatic force and hydrogen bonding. Moreover, SHGEY and SPYGF could significantly up-regulate the nitric oxide (NO) production and decrease the endothelin-1 (ET-1) secretion in human umbilical vein endothelial cells (HUVECs), but also abolished the negative impacting of norepinephrine to the levels of NO and ET-1. Furthermore, SHGEY and SPYGF showed significant protection to HUVECs against H2O2 damage by increasing superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity to lower the contents of reactive oxide species and malondialdehyde. Consequently, ACEi peptides derived from miiuy croaker swim bladders, especially SHGEY and SPYGF, are health-promoting ingredients for functional products as a supplementary treatment to hypertension and cardiovascular diseases.

Bioactive Peptides from Skipjack Tuna Cardiac Arterial Bulbs: Preparation, Identification, Antioxidant Activity, and Stability against Thermal, pH, and Simulated Gastrointestinal Digestion Treatments

“…The characteristics of proteases are the most crucial element affecting the composition and structure of BPs, which further influence the biological functions of protein hydrolysates [ 7 , 50 , 56 ]. Then, a variety of protease species, including Neutrase, papain, pepsin, Alcalase, Flavourzyme, chymotrypsin, and protamex, were screened, optimized, and used in the preparation of protein hydrolysates from multiple marine organisms and their by-products, such as Antarctic Krill [ 50 ], skate cartilages [ 5 ], miiuy croaker swim bladders [ 9 ], monkfifish muscle [ 21 ], Pacific cod skins [ 28 ], and tuna black muscles and scales [ 36 , 41 ]. The present results proved again that the specificity of proteases could significantly affect the peptide composition of protein hydrolysates, which are closely related to their antioxidant activity.…”

“…Bioactive peptides (BPs) are usually composed of 2–20 amino acid (AA) residues and generated from plant, animal, and microorganism proteins by chemical degradation, biological fermentation, and enzymatic hydrolysis methods [ 1 , 2 , 3 , 4 ]. Beyond their well-recognized nutritional value, BPs have been turned out to be of great value in advancing human health because of their significant biological activities including anticancer [ 5 , 6 ], antioxidant [ 7 ], antihypertensive [ 8 , 9 ], antiinflammatory [ 10 ], hypolipidemic [ 11 ], immunoreglatory [ 6 ], anti-diabetic [ 12 ], and mineral binding activities [ 13 ]. Presently, global annualfish production is about 1.79 × 10 8 tons and around 50% of these by-catches turn into processing byproducts in factories [ 14 , 15 ].…”

Swim Bladder of Farmed Totoaba macdonaldi: A Source of Value-Added Collagen

“…The totoaba swim bladder has putatively positive therapeutic effects in traditional Chinese medicine [ 6 ]. Peptides and collagen from croaker swim bladders have been shown to remove free radicals [ 17 , 20 , 21 ]. The DPPH radical scavenging assay is a popular and efficient way of predicting antioxidant activity since the DPPH radical is more stable than hydroxyl and superoxide radicals [ 19 ].…”

“…Additionally, the fish swim bladder has been used to obtain peptides with multiple physiological activities and functions after hydrolysis with proteases [ 17 ]. For example, collagen hydrolysates from the swim bladder of the croceine croaker ( Pseudosciaena crocea ) and miiuy croaker exhibit anti-fatigue, anti-amnesic, antioxidant, and antihypertensive activities [ 18 , 19 , 20 , 21 ]. However, no research has been done to date on the essential biochemical composition of the totoaba swim bladder or the properties of its collagen.…”

Production, identification, in silico analysis, and cytoprotection on H2O2-induced HUVECs of novel angiotensin-I-converting enzyme inhibitory peptides from Skipjack tuna roes

“…Presently, some natural ACE inhibitors, including quinones, flavonoids, polyphenols, sesquiterpenoids, and alkaloids have been prepared from different creatures ( 23 , 24 ), and ACEi peptides from animals, plants and microbes arouse the concern of consumers and researchers because their medical and nutritional benefits ( 25 ). Because of the particularity and diversity of marine proteins, ACEi peptides have been generated from different marine creatures, such as rainbow trout ( Oncorhynchus mykiss ) ( 26 ), Mytilus edulis ( 17 ), Ruditapes philippinarum ( 27 ), lizard fish ( Saurida elongata ) ( 28 ), jellyfish ( Rhopilema esculentum ) ( 29 ), Nile tilapia ( Oreochromis niloticus ) ( 30 ), Okamejei kenojei ( 31 ), Salmo salar ( 32 ), etc.…”