Effect of protein hydrolysates from carp (Cyprinus carpio) skin gelatine on oxidative stress biomarkers and other blood parameters in healthy rats

Novel Peptide Sequences with ACE-Inhibitory and Antioxidant Activities Derived from the Heads and Bones of Hybrid Groupers (Epinephelus lanceolatus × Epinephelus fuscoguttatus)

The heads and bones of hybrid groupers are potential precursors for angiotensin-converting enzyme (ACE)-inhibitory and antioxidant peptides. The aim of this study was to isolate the dual-action peptides from the Alcalase-treated head and bone hydrolysate of hybrid groupers followed by identification of the novel peptides. The stability of these peptides against stimulated in vitro gastrointestinal digestion (SGID) was also determined. Fraction HB-IV (less than 1 kDa) obtained from ultrafiltration showed the strongest ACE-inhibition ability (IC50: 0.28 mg/mL), which was comparable to the potency of the commercial supplement, PeptACE (IC50: 0.22 mg/mL). This fraction also demonstrated the highest hydroxyl radical scavenging and metal-chelating activities. However, further fractionation of HB-IV by a series of chromatography resulted in peptide fractions of reduced ACE-inhibitory and antioxidant activities. The hydroxyl radical scavenging and reduction potential of HB-IV were enhanced, whereas ACE-inhibitory and metal-chelating activities were reduced following SGID. A total of 145 peptide sequences were identified from HB-IV, of which 137 peptides were novel to the BIOPEP database. The results suggested that the bioactive peptides isolated from the heads and bones of hybrid groupers could be used as functional foods/ingredients with potential ACE-inhibitory and antioxidant effects.

Influence of 5-Week Snack Supplementation with the Addition of Gelatin Hydrolysates from Carp Skins on Pro-Oxidative and Antioxidant Balance Disturbances (TOS, TAS) in a Group of Athletes

The research objective was to assess the effects of 5-week snack supplementation with added enzymatic hydrolysates from carp skins on shifts in pro-oxidative and antioxidant balance among athletes. The study comprised 49 adults (experimental group (E)—17, placebo (P)—16, control (C)—16) practicing endurance disciplines. Selected somatic indices and maximal oxygen uptake/m (VO2max) were measured. Based on VO2max, an individual exercise intensity was selected with predominating eccentric contractions (60% VO2max). The conducted tests consisted of 2 series (1st—graded and eccentric, 2nd—eccentric). The experimental group consumed a snack with added gelatin hydrolysates from carp skins for 5 weeks in between the series, the placebo—a snack without added hydrolysates, and in the control—no supplementation was implemented. Blood samples were taken before, and 1, 24 and 48 h after completion of the eccentric test. TAS and TOC concentrations in the blood plasma were assessed. No significant changes in TOS/TOC and TAS/TAC concentrations were noted between the 1st and the 2nd test series, before or following the eccentric test in the control and placebo groups. In the measurements performed 1, 24 and 48 h after completion, the observed differences were highly significant (p < 0.001). After 5 weeks of snack consumption, an increase from medium to high antioxidant potential was observed for E. Differences between the 1st and the 2nd test series were of high statistical significance (p < 0.001). The demonstrated differences in pro-oxidative-antioxidant balance indices between successive series allow to confirm antioxidant effects and indicate possibilities for its implementation, not only in sports.

Marine Products As a Promising Resource of Bioactive Peptides: Update of Extraction Strategies and Their Physiological Regulatory Effects

Marine products are a rich source of nutritional components and play important roles in promoting human health. Fish, mollusks, shellfish, as well as seaweeds are the major components of marine products with high-quality proteins. During the last several decades, bioactive peptides from marine products have gained much attention due to their diverse biological properties including antioxidant, antihypertensive, antimicrobial, antidiabetic, immunoregulation, and antifatigue. The structural characteristics of marine bioactive peptides largely determine the differences in signaling pathways that can be involved, which is also an internal mechanism to exert various physiological regulatory activities. In addition, the marine bioactive peptides may be used as ingredients in food or nutritional supplements with the function of treating or alleviating chronic diseases. This review presents an update of marine bioactive peptides with the highlights on the novel producing technologies, the physiological effects, as well as their regulation mechanisms. Challenges and problems are also discussed in this review to provide some potential directions for future research.

Roles of Dietary Bioactive Peptides in Redox Balance and Metabolic Disorders

Bioactive peptides (BPs) are fragments of 2-15 amino acid residues with biological properties. Dietary BPs derived from milk, egg, fish, soybean, corn, rice, quinoa, wheat, oat, potato, common bean, spirulina, and mussel are reported to possess beneficial effects on redox balance and metabolic disorders (obesity, diabetes, hypertension, and inflammatory bowel diseases (IBD)). Peptide length, sequence, and composition significantly affected the bioactive properties of dietary BPs. Numerous studies have demonstrated that various dietary protein-derived BPs exhibited biological activities through the modulation of various molecular mechanisms and signaling pathways, including Kelch-like ECH-associated protein 1/nuclear factor erythroid 2-related factor 2/antioxidant response element in oxidative stress; peroxisome proliferator-activated-γ, CCAAT/enhancer-binding protein-α, and sterol regulatory element binding protein 1 in obesity; insulin receptor substrate-1/phosphatidylinositol 3-kinase/protein kinase B and AMP-activated protein kinase in diabetes; angiotensin-converting enzyme inhibition in hypertension; and mitogen-activated protein kinase and nuclear factor-kappa B in IBD. This review focuses on the action of molecular mechanisms of dietary BPs and provides novel insights in the maintenance of redox balance and metabolic diseases of human.

Antioxidant properties of Klunzinger's mullet (Liza klunzingeri) protein hydrolysates prepared with enzymatic hydrolysis using a commercial protease and microbial hydrolysis with Bacillus licheniformis

Antioxidant activity of Klunzinger's mullet (Liza klunzingeri) muscle hydrolysates obtained using Bacillus licheniformis fermentation and enzymatic hydrolysis was determined. Hydrolysates obtained after 6 days of fermentation with B. licheniformis showed the highest free radical scavenging activity, metal chelating ability and ferric reducing antioxidant power (FRAP) (P ≤ 0.05). Microbial fermentation led to a higher percentage of small peptides and higher solubility compared with Alcalase hydrolysis (P ≤ 0.05). Hydrolysates showing the highest antioxidant properties attenuated serum, liver, and kidney oxidative stress biomarkers in male Wister rats stressed by carbon tetrachloride (P ≤ 0.05). At 300 mg/kg oral administration, hydrolysates increased serum, renal, and hepatic total antioxidant capacity (TAC) (P ≤ 0.05) and reduced their elevated levels of malondialdehyde (MDA), nitric oxide (NO^•), and serum liver enzymes (AST, ALP, and ALT) (P ≤ 0.05). The hydrolysates were able to ameliorate hepatic damage by reducing necrosis, fatty changes, and inflammation. Results showed the antioxidant and hepato-toxic protective activities of Klunzinger's mullet muscle hydrolysates obtained using microbial fermentation, which may, therefore, potentially be considered as a functional food ingredient.

Protocol for Designing New Functional Food with the Addition of Food Industry By-Products, Using Design Thinking Techniques-A Case Study of a Snack with Antioxidant Properties for Physically Active People

The aim of the work was to develop an easy-to-follow protocol for designing novel functional products with the addition of food industry by-products using design thinking techniques. As a result, a 12-step protocol has been designed and presented. The protocol consists of steps from the initial formation of the design team, through all the stages of the production and prototyping, until establishing the final storage conditions and creating final documentation. The protocol has been validated and explained using a case study in which a fish industry by-product hydrolysate with bioactive properties was used to develop a novel functional food product for physically active people: a date bar with carp meat and carp skin gelatin hydrolysate. Following the 12 steps presented in the protocol resulted in developing a food product with high nutritional value and antioxidant power which remains stable during storage at reduced temperatures. Moreover, the product is characterized by good sensory qualities and can be easily implemented into full-scale production. The newly designed protocol is an easy-to-follow method that could be used in almost any kind of food industry sector to sucesfully develop user-focused functional food products with by-product addition.

Advances on Food-Derived Peptidic Antioxidants-A Review

The oxidation process is considered to be the main reason behind human aging, human degenerative diseases and food quality degradation. Food-derived peptidic antioxidants (PAs) have wide sources and great activity, and have broad application prospects in removing excess reactive oxygen species in the body, anti-aging and preventing and treating diseases related to oxidative stress. On the other hand, PAs are expected to inhibit the lipid peroxidation of foods and increase the stability of the food system in the food industry. However, the production pathways and action mechanism of food-derived PAs are diverse, which makes it is difficult to evaluate the performance of PAs which is why the commercial application of PAs is still in its infancy. This article focuses on reviewing the preparation, purification, and characterization methods of food-derived PAs, and expounds the latest progress in performance evaluation and potential applications, in order to provide an effective reference for subsequent related research of PAs.

Furcellaran-Coated Microcapsules as Carriers of Cyprinus carpio Skin-Derived Antioxidant Hydrolysate: An In Vitro and In Vivo Study

Carp skin gelatine hydrolysate (CSGH) may be a possible bioactive peptide source, as promising antioxidant properties have been noted during in vivo testing. Hence, the present study focused on improving the bioavailability of the antioxidant peptides from CSGH and on the use of furcellaran (FUR), which can protect the biopeptides during digestion in the gastrointestinal tract. Therefore, in this study, microcapsules coated with furcellaran and containing CSGH cores were prepared. The structural properties of the sample were determined using FT-IR and SEM analysis. The antioxidant properties of hydrolysate, uncoated, and encapsulated samples were investigated. In vivo analysis included determination of its safety in an animal organism and evaluation of the lipid profile, antioxidant blood status, and mRNA expression of some genes involved in antioxidant status in Wistar rats. The results showed no adverse effects of microencapsulated protein hydrolysates in laboratory animals. Nonetheless, there was a statistically significant rise in the level of total antioxidant status blood serum among animals consuming CSGH and not inducing oxidative stress. This can be viewed as a promising indication of the positive effects of antioxidant properties tested in vivo. The process of CSGH microencapsulation in FUR cause a decrease in antioxidant hydrolysate activity, both in vitro, as well as in healthy Wistar rats. When considering the results of the presented diverse therapeutic potential, further research on CSGH being a potential bioactive peptide source used as a functional food or nutraceutical, but with a different microencapsulation coating, is encouraged.