Hempseed protein-derived short- and medium-chain peptides and their multifunctional properties.

Nowadays, the growing knowledge about the high nutritional value and potential functionality of hempseeds, the edible fruits of the Cannabis sativa L. plant, has sparked a surge in interest in exploring the worthwhile attributes of hempseed proteins and peptides. This trend aligns with the increasing popularity of hemp-based food, assuming a vital role in the global food chain. This chapter targets the nutritional and chemical composition of hempseed in terms of short- and medium-chain bioactive peptides. The analytical approaches for their characterization and multifunctional properties are summarized in detail. Moreover, the processing, functionality, and application of various hempseed protein products are discussed. In the final part of the chapter-for evaluating their propensity to be transported by intestinal cells-the transepithelial transport of peptides within hempseed protein hydrolysate is highlighted.

[Cow's milk allergy treatment. An expert consensus]. / Tratamiento de la alergia a la proteína de la leche de vaca. Consenso interdisciplinario de expertos.

The treatment of cow's milk protein allergy is based on the complete elimination of cow's milk protein from the diet. To achieve remission of symptoms and future tolerance, exclusion must be total. In formula fed infants the extensively hydrolysed formula is the most appropriate option in mild or moderate forms, while those based on amino acids are reserved for the most severe cases. The treatment time, the acquisition of tolerance and the moment for the oral provocation test will vary according to the clinical picture, the immunological mechanism involved and the age of the patient. The aim of this consensus has been to reflect the updated knowledge together with the experience of neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology.

El tratamiento de la alergia a las proteínas de la leche de vaca se basa en la eliminación completa de las proteínas de leche de vaca de la dieta del niño y de la madre en los que reciben leche materna. Para lograr la remisión de los síntomas y la tolerancia futura, la exclusión debe ser total. En los niños que reciben fórmula, esta deberá tener hidrolizado extenso de proteínas en las formas leves o moderadas, mientras que aquellas a base de aminoácidos se reservan para los casos más graves. El tiempo de tratamiento, la adquisición de tolerancia y el momento para la prueba de provocación oral van a variar según el cuadro clínico, el mecanismo inmunológico implicado y la edad del paciente. El objetivo de este consenso ha sido reflejar el conocimiento actualizado junto con la experiencia de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología.

Protein-based oral rehydration solutions for patients with an ileostomy: A randomised, double-blinded crossover study.

BACKGROUND & AIM: Patients with an ileostomy are at increased risk of dehydration and sodium depletion. Treatments recommended may include oral rehydration solutions (ORS). We aimed to investigate if protein type or protein hydrolysation affects absorption from iso-osmolar ORS in patients with an ileostomy. METHODS: This was a randomised, double-blinded, active comparator-controlled 3 × 3 crossover intervention study. We developed three protein-based ORS with whey protein isolate, caseinate or whey protein hydrolysate. The solutions contained 40-48 g protein/L, 34-45 mmol sodium/L and had an osmolality of 248-270 mOsm/kg. The patients ingested 500 mL/d. The study consisted of three 4-week periods with a >2-week washout between each intervention. The primary outcome was wet-weight ileostomy output. Ileostomy output and urine were collected for a 24-h period before and after each intervention. Additionally, blood sampling, dietary records, muscle-strength tests, bioimpedance analyses, questionnaires and psychometric tests were conducted. RESULTS: We included 14 patients, of whom 13 completed at least one intervention. Ten patients completed all three interventions. Wet-weight ileostomy output did not change following either of the three interventions and did not differ between interventions (p = 0.38). A cluster of statistically significant improvements related to absorption was observed following the intake of whey protein isolate ORS, including decreased faecal losses of energy (-365 kJ/d, 95% confidence interval (CI), -643 to -87, p = 0.012), potassium (-7.8 mmol/L, 95%CI, -12.0 to -3.6, p = 0.001), magnesium (-4.0 mmol/L, 95%CI, -7.4 to -0.7, p = 0.020), improved plasma aldosterone (-4674 pmol/L 95%CI, -8536 to -812, p = 0.019), estimated glomerular filtration rate (eGFR) (2.8 mL/min/1.73 m2, 95%CI, 0.3 to 5.4, p = 0.03) and CO2 (1.7 mmol/L 95%CI, 0.1 to 3.3, p = 0.04). CONCLUSION: Ingestion of 500 mL/d of iso-osmolar solutions containing either whey protein isolate, caseinate or whey protein hydrolysate for four weeks resulted in unchanged and comparable ileostomy outputs in patients with an ileostomy. Following whey protein isolate ORS, we observed discrete improvements in a series of absorption proxies in both faeces and blood, indicating increased absorption. The protein-based ORS were safe and well-tolerated. Treatments should be tailored to each patient, and future studies are warranted to explore treatment-effect heterogeneity and whether different compositions or doses of ORS can improve absorption and nutritional status in patients with an ileostomy. GOV STUDY IDENTIFIER: NCT04141826.

Protein and Polysaccharide Recovery from Shrimp Wastes by Natural Deep Eutectic Solvent Mediated Subcritical Water Hydrolysis for Biodegradable Film.

Environmental pollution is a significant problem due to the improper disposal of plastics and shrimp shells outdoors. Therefore, the synthesis of biodegradable film from waste materials is highly important. The novelty of this research lies in the extraction of protein hydrolysates and chitosan from shrimp shells, as well as the fabrication of biodegradable film from these materials. In this study, the composite films were produced using the solution casting method. Moreover, the combined effect of ultrasound pretreatments (UPT) and natural deep eutectic solvents (NADES) was investigated as extraction media, to determine their potential impact on shrimp waste subcritical water hydrolysis (SWH). Shrimp shells were submitted to UPT in NADES solution, followed by SWH at different temperatures ranging from 150 to 230 °C under 3 MPa for 20 min. Then, the physiochemical properties and bioactivities of the hydrolysates were assessed to determine their suitability for use in biodegradable packaging films. Additionally, the physiochemical properties and bioactivities of the resulting hydrolysates were also analyzed. The highest amount of protein (391.96 ± 0.48 mg BSA/g) was obtained at 190 °C/UPT/NADES, and the average molecular size of the protein molecules was less than 1000 Da with different kinds of peptide. Overall, combined UPT and SWH treatments yielded higher antioxidant activity levels than individual treatments. Finally, the application of composite films was evaluated by wrapping fish samples and assessing their lipid oxidation. The use of higher concentrations of protein hydrolysates significantly delayed changes in the samples, thereby demonstrating the film's applicability.

Optimal and sustainable production of tailored fish protein hydrolysates from tuna canning wastes and discarded blue whiting: Effect of protein molecular weight on chemical and bioactive properties.

Thousands tons of discards of blue whiting (BW) and tuna heads (YT) by-products are generated each year in Europe. BW is the species most discarded by European fishing fleet and, in some canning factories, YT are processed for the retrieval of oil rich in omega-3, but producing a huge amount of solid remains and effluents disposal as wastes. The development of optimal and sustainable processes for both substrates is mandatory in order to reach clean solutions under the circular economy precepts. This work focused on the mathematical optimization of the production of tailored fish protein hydrolysates (FPH), from blue whiting and tuna residues, in terms of controlling average molecular weights (Mw) of proteins. For the modeling of the protein depolymerization time-course, a pseudo-mechanistic model was used, which combined a reaction mechanistic equation affected, in the kinetic parameters, by two non-lineal equations (a first-order kinetic and like-Weibull formulae). In all situations, experimental data were accurately simulated by that model achieving R2 values higher than 0.96. The validity of the experimental conditions obtained from modeling were confirmed performing productions of FPH at scale of 5 L-reactor, without pH-control in most of cases, at the different ranges of Mw selected (1-2 kDa, 2-5 kDa and 5-10 kDa). The results showed that FPH from BW with lower Mw led to a remarkable yield of production (12 % w/w of substrate), largest protein contents (77 % w/w of BW hydrolysate), greatest in vitro digestibility (>95 %), highest essential amino acid presence (43 %) and the best antioxidant (DPPH = 62 %) and antihypertensive (IC50-ACE = 80 mg/L) properties. Our results prove that the proposed procedure to produce sustainable FPH, with specific Mw characterisitics, could be extended to other fish waste substrates. Tailored FPH may have the potential to serve as valuable ingredients for functional foods and high-quality aquaculture feed.

Long-term effects of an egg-protein hydrolysate on cognitive performance and brain vascular function: a double-blind randomized controlled trial in adults with elevated subjective cognitive failures.

PURPOSE: Short-term intake of the egg-protein hydrolysate Newtricious (NWT)-03 improved executive function, but underlying mechanisms and long-term effects, including other cognitive domains, are unknown. METHODS: A 36-week randomized controlled trial involving 44 overweight/obese individuals experiencing elevated Subjective Cognitive Failures (SCF; aged 60-75 years) assessed the impact of daily consumption of 5.7 g of NWT-03 or placebo powders on cognitive performance (psychomotor speed, executive function, memory) and Cerebral Blood Flow (CBF), a marker of brain vascular function. Cognitive performance was evaluated using a neurophysiological test battery (CANTAB) and CBF was measured using magnetic resonance imaging perfusion method Arterial Spin Labeling (ASL). Serum samples were collected to determine brain-derived neurotrophic factor (BDNF) concentrations. RESULTS: Anthropometrics, and energy and nutrient intakes remained stable throughout the trial. NWT-03 was well tolerated, and compliance was excellent (median: 99%; range: 87-103%). No overall intervention effects were observed on cognitive performance or CBF, but post-hoc analyses revealed significant improvements on executive function in women, but not men. Specifically, a reduction of 74 ms in reaction latency on the multitasking task (95% CI: -134 to -15; p = 0.02), a reduction of 9 between errors (95%CI: -14 to -3; p < 0.001), and a reduction of 9 total errors (95%CI: -15 to -3; p < 0.001) on the spatial working memory task were found in women. No intervention effects were observed on serum BDNF concentrations (p = 0.31). CONCLUSION: Long-term consumption of NWT-03 improved multitasking abilities and working memory in women with elevated SCF. Brain vascular function remained unaffected. Sex differences in executive function require additional clarification.

A comprehensive investigation of the use of freeze concentration appro aches for the concentration of fish protein hydrolysates.

Fish protein hydrolysates (FPH) are inherently unstable in their liquid form, necessitating either freezing or dewatering for stabilization. Gentle methods such as freeze concentration can be used to remove water, this can be achieved by freezing water in solution by decreasing the bulk temperature below freezing point and separating pure ice crystals from concentrated solution. This approach serves as an alternative to techniques like evaporation and reverse osmosis for concentrating solutions that have high water content, significant nutritional value, and thermolabile compounds. This is crucial as many bioactive compounds degrade when exposed to elevated temperatures. Another notable advantage of this technology is its potential to reduce energy consumption by up to 40% when integrated into the FPH drying process. Although this technology is currently industrialized primarily for juices, it can achieve concentrations of up to 60°Brix and manage viscosities up to 400 mPa.s. Numerous studies have been dedicated to enhancing design and processes, leading to a 35% reduction in the system's capital cost and a 20% reduction in energy consumption. Moreover, freeze concentration can synergize with other concentration techniques, creating more efficient hybrid processes. This review aims to introduce freeze concentration as a superior option for preserving fish protein hydrolysates, enhancing their stability, and maintaining their nutritional and bioactive qualities.

Banana peel nanocellulose and soy protein hydrolysate complexed colloidal nanoparticles synthesis using ultrasonic interventions: characterization and stable pickering emulsion formation.

Pickering based emulsion system are been gaining interest in active delivery of encapsulated molecules in food system. In the present study, cellulose nanoparticles (CNPs) were isolated from food waste (banana peel) using acid hydrolysis followed by high-intensity ultrasonication. The complex colloidal nanoparticles (CNPSPH) were fabricated using hydrogen bonding and electrostatic interactions between cellulose nanoparticles and soy protein hydrolysates. With 400 W power level for 30 min, size of 53.11 ± 1.45 nm with polydispersity index of 0.21 ± 0.21 and Zeta potential of - 34.33 ± 0.77 were noted for generated CNPs. The three-phase contact angle (o/w) of CNPSPH at a mass ratio of 1:1 CNPs to SPHs (CNPSPH 1:1) was approximately 89.07°, indicating as effective Pickering emulsifiers. Furthermore, the stability of the Pickering emulsion stabilised by CNPSPH complex was investigated under various pH and temperature conditions. The findings will provide solution in development of nanocellulose-soy protein complex particles for a stabilized Pickering emulsion formation. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01477-w.

Conjugation of gum Arabic and lentil protein hydrolysates through Maillard reaction: Antioxidant activity, volatile compounds, functional and sensory properties.

Lentil protein hydrolysates (LPH) and lentil protein hydrolysates cross-linked (LPHC) were grafted with gum Arabic (GA) through a wet Maillard reaction at 100°C for 2 h and called MLPH and MLPHC. The samples were assessed for absorption, degree of grafting (DG), surface hydrophobicity, antioxidant activity, molecular weight (MW) profile, chemical alteration, volatile compounds, functional and sensory properties. Results showed that Maillard grafting led to increase in absorption and DG (maximum value: MLPHC), and led to the reduction of the surface hydrophobicity and antioxidant activity (minimum value: MLPHC). MW profiles indicated that MLPH and MLPHC formed new bands at MW >250 kDa. Regarding the Fourier transform infrared spectroscopy (FTIR), Maillard conjugation led to the occurrence of peaks at 1759 and 1765 cm-1, while the intensities of amide I bands at 1637 and 1659 cm-1 and amide II bands at 1498 and 1495 cm-1 were decreased. Hydrolysis, cross-linking, and especially Maillard grafting provided well-balanced content of volatile components. Indeed, the proportions of alcohols, ketones, aldehydes, and acids were changed, thereby, the inherent grassy and planty tastes were diminished while new umami taste was developed. Maillard grafting led to significant improvement of functional properties, while MLPH and MLPHC indicated the highest emulsifying activity at pH 10.0 (73.76 and 70.12 m2/g, respectively) and stability (369.64 and 288.22 min), foaming capacity (88.57% and 142.86%) and stability (60.57% and 72%). Sensory analysis has demonstrated that umami taste was highly developed in MLPH and MLPHC, which can be well considered as meat proteins and flavor enhancers such as monosodium glutamate (MSG).

Glycated Walnut Meal Peptide-Calcium Chelates: Preparation, Characterization, and Stability.

Finding stable and bioavailable calcium supplements is crucial for addressing calcium deficiency. In this study, glycated peptide-calcium chelates (WMPHs-COS-Ca) were prepared from walnut meal protein hydrolysates (WMPHs) and chitosan oligosaccharides (COSs) through the Maillard reaction, and the structural properties and stability of the WMPHs-COS-Ca were characterized. The results showed that WMPHs and COSs exhibited high binding affinities, with a glycation degree of 64.82%. After glycation, Asp, Lys, and Arg decreased by 2.07%, 0.46%, and 1.06%, respectively, which indicated that these three amino acids are involved in the Maillard reaction. In addition, compared with the WMPHs, the emulsifying ability and emulsion stability of the WMPHs-COS increased by 10.16 mg2/g and 52.73 min, respectively, suggesting that WMPHs-COS have better processing characteristics. After chelation with calcium ions, the calcium chelation rate of peptides with molecular weights less than 1 kDa was the highest (64.88%), and the optimized preparation conditions were 5:1 w/w for WMPH-COS/CaCl2s, with a temperature of 50 °C, a chelation time of 50 min, and a pH of 7.0. Scanning electron microscopy showed that the "bridging role" of WMPHs-COS changed to a loose structure. UV-vis spectroscopy and Fourier transform infrared spectrometry results indicated that the amino nitrogen atoms, carboxyl oxygen atoms, and carbon oxygen atoms in WMPHs-COS chelated with calcium ions, forming WMPHs-COS-Ca. Moreover, WMPHs-COS-Ca was relatively stable at high temperatures and under acidic and alkaline environmental and digestion conditions in the gastrointestinal tract, indicating that WMPHs-COS-Ca have a greater degree of bioavailability.

Purification and identification of novel antioxidant peptides derived from Bombyx mori pupae hydrolysates.

The biological importance of antioxidant peptides was the focus of new natural sources of food preservatives. Bombyx mori pupae are considered a valuable by-product of the silk-reeling industry due to their high-quality protein content. This study aimed to purify and identify the antioxidant peptides obtained from enzymatically hydrolyzed B. mori pupae, which could be used as new sources of natural food preservatives. Among the prepared hydrolysates, pepsin hydrolysate with the highest antioxidant activities was purified sequentially using ultrafiltration and reversed-phase high-performance liquid chromatography (RP-HPLC). The DPPH radical scavenging and ferrous ion chelating activity were used to evaluate antioxidant activity. Fractions with high activity were further analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Three peptides were identified as Glu-Asn-Ile-Ile-Leu-Phe-Arg (ENIILFR), Leu-Asn-Lys-Asp-Leu-Met-Arg (LNKDLMR), and Met-Leu-Ile-Ile-Ile-Met-Arg (MLIIIMR), respectively. All three novel identified peptides exhibited significantly stronger antioxidant capacity than synthetic antioxidants used in the food industry, including butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT). ENIILFR showed the best antioxidant activity. These findings indicate that the three peptides have potential applications as natural antioxidants in the food industry.

Feasibility of Enzymatic Protein Extraction from a Dehydrated Fish Biomass Obtained from Unsorted Canned Yellowfin Tuna Side Streams: Part II.

The enzymatic extraction of proteins from fish biomasses is being widely investigated. However, little or almost no research has paid attention to the exploitation of unsorted fishery biomasses. This work is part of a larger study, Part I of which has already been published, and focuses on an extensive characterization of two collagenous samples, namely gelatin (G) and hydrolyzed gelatin peptides (HGPs), extracted from a dehydrated fish biomass coming from unsorted canned yellowfin tuna side streams. The results indicate crude protein fractions of 90-93%, pH values between 3 and 5, white-yellow colors, collagen-like FTIR spectra, and 17% in terms of total amino acid content. Viscosity and the study of dynamic viscous-elastic behavior were analyzed. Thermo-gravimetric analysis was performed to assess the residual ashes. Both samples were investigated to determine their molecular weight distribution via size-exclusion chromatography, with a higher total average molecular weight for G compared to HGPs, with values of 17,265.5 Da and 2637.5 Da, respectively. G demonstrated technological properties similar to analogous marine gelatins. HGPs demonstrated antioxidant activity as per FRAP assay. All the results open up new perspectives for the potential use of these substances in biodegradable packaging, dietary supplements, and skin care cosmetics.

Protein Hydrolysis as a Way to Valorise Squid-Processing Byproducts: Obtaining and Identification of ACE, DPP-IV and PEP Inhibitory Peptides.

The industrial processing of Argentine shortfin squid to obtain rings generates a significant amount of protein-rich waste, including the skin, which is rich in collagen and attached myofibrillar proteins. This waste is generally discarded. In this study, skin was used as a source of proteins that were hydrolysed using Trypsin, Esperase® or Alcalase®, which released peptides with antioxidant potential and, in particular, antihypertensive (ACE inhibition), hypoglycemic (DPP-IV inhibition) and/or nootropic (PEP inhibition) potential. Among the three enzymes tested, Esperase® and Alcalase produced hydrolysates with potent ACE-, DPP-IV- and PEP-inhibiting properties. These hydrolysates underwent chromatography fractionation, and the composition of the most bioactive fractions was analysed using HPLC-MS-MS. The fractions with the highest bioactivity exhibited very low IC50 values (16 and 66 µg/mL for ACE inhibition, 97 µg/mL for DPP-IV inhibition and 55 µg/mL for PEP inhibition) and were mainly derived from the hydrolysate obtained using Esperase®. The presence of Leu at the C-terminal appeared to be crucial for the ACE inhibitory activity of these fractions. The DPP-IV inhibitory activity of peptides seemed to be determined by the presence of Pro or Ala in the second position from the N-terminus, and Gly and/or Pro in the last C-terminal positions. Similarly, the presence of Pro in the peptides present in the best PEP inhibitory fraction seemed to be important in the inhibitory effect. These results demonstrate that the skin of the Argentine shortfin squid is a valuable source of bioactive peptides, suitable for incorporation into human nutrition as nutraceuticals and food supplements.

Mitigation of salt stress in lettuce by a biostimulant that protects the root absorption zone and improves biochemical responses.

Horticultural crops constantly face abiotic stress factors such as salinity, which have intensified in recent years due to accelerated climate change, significantly affecting their yields and profitability. Under these conditions, it has become necessary to implement effective and sustainable solutions to guarantee agricultural productivity and food security. The influence of BALOX®, a biostimulant of plant origin, was tested on the responses to salinity of Lactuca sativa L. var. longifolia plants exposed to salt concentrations up to 150 mM NaCl, evaluating different biometric and biochemical properties after 25 days of treatment. Control plants were cultivated under the same conditions but without the biostimulant treatment. An in situ analysis of root characteristics using a non-destructive, real-time method was also performed. The salt stress treatments inhibited plant growth, reduced chlorophyll and carotenoid contents, and increased the concentrations of Na+ and Cl- in roots and leaves while reducing those of Ca2+. BALOX® application had a positive effect because it stimulated plant growth and the level of Ca2+ and photosynthetic pigments. In addition, it reduced the content of Na+ and Cl- in the presence and the absence of salt. The biostimulant also reduced the salt-induced accumulation of stress biomarkers, such as proline, malondialdehyde (MDA), and hydrogen peroxide (H2O2). Therefore, BALOX® appears to significantly reduce osmotic, ionic and oxidative stress levels in salt-treated plants. Furthermore, the analysis of the salt treatments' and the biostimulant's direct effects on roots indicated that BALOX®'s primary mechanism of action probably involves improving plant nutrition, even under severe salt stress conditions, by protecting and stimulating the root absorption zone.

Wheat Protein Hydrolysates Improving the Stability of Purple Sweet Potato Anthocyanins under Neutral pH after Commercial Sterilization at 121 °C.

Anthocyanins are prone to degradation and color fading after sterilization. This work examined the potential of wheat protein hydrolysates (WPHs, 40 g/L) in improving the stability of purple sweet potato anthocyanins (PSPAs) under a pH of 6.8 after sterilization at 121 °C followed by storage. Results showed that WPHs increased the thermal degradation half-life of PSPAs 1.65 times after sterilization. Compared to PSPAs alone, after being stored at 37 °C and 45 °C for 7 days, the retention concentration of PSPAs with WPHs was 5.4 and 32.2 times higher, and the color change of PSPAs with WPHs decreased from 6.19 and 10.46 to 0.29 and 0.77, respectively. AFM data, fluorescence and UV spectrograms indicated the formation of complexes between PSPAs and WPHs by hydrophobic attraction confirmed by zeta-potential data. PSPAs with WPHs had stable particle size and zeta potential, which may also significantly increase the concentrations after digestion and antioxidant power of PSPAs. This work indicated that the assembled PSPAs composite structure by WPHs significantly reduced the degradation of PSPAs at a pH of 6.8 after sterilization at 121 °C followed by long-term storage.

Comparison of amino acid release between enzymatic hydrolysis and acid autolysis of rainbow trout viscera.

Fish protein hydrolysates were obtained from cultured rainbow trout (Oncorhynchus mykiss) viscera using commercial and endogenous enzymes. Two methods were employed for hydrolysis: acid autolysis (also known as silage) at room temperature for 10 days in acidic conditions, until total solubilisation, and enzymatic hydrolysis using Alcalase 2.4 LFG, Protana Prime, and the endogenous enzymes in the viscera. The effectiveness of both methods in releasing free amino acids (FAA) was assessed. After evaluating the results, the most effective enzymatic hydrolysis was optimized. The findings indicated that enzymatic hydrolysis with Alcalase, Protana Prime and endogenous enzymes combined for 7 h at a dose of 1% of protein, and a 7-day acid autolysis yielded the highest degree of hydrolysis (83.8% and 75.8%), a yield of FAA from viscera of 5.9% and 3.2%, and a yield of FAA from total protein of 71.3% and 52.5%, respectively. In conclusion, the use of commercial enzymes was more efficient in releasing amino acids, but endogenous enzymes showed a strong proteolytic capacity during acid autolysis, suggesting it also as a promising method to produce FAA-rich hydrolysates.

Identification and anti-oxidative potential of milk fat globule membrane (MFGM)-derived bioactive peptides released through in vitro gastrointestinal digestion.

This study investigated the stability of milk fat globule membrane (MFGM) protein under simulated gastrointestinal conditions using an in vitro enzymatic digestion method. The optimal hydrolysis conditions were determined by monitoring the changes in particle size and zeta-potential of MFGM protein hydrolysates over time. Furthermore, the distribution of small molecular weight peptides with antioxidant activity was explored through DEAE-52 combined with in vitro cell experiments. Two novel antioxidant peptides (TGIIT and IITQ) were identified based on molecular docking technology and evaluated their potential scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS+) radicals. TGIIT and IITQ also demonstrated remarkable abilities in promoting mitochondrial biogenesis and activating Keap1/Nrf2 signaling pathway, which can effectively counteract skeletal muscle dysfunction induced by oxidative stress. Thus, MFGM-derived antioxidant peptides have the potential to be employed in food to regulate muscle protein metabolism and alleviate sarcopenia.

PeposX-Exhaust: A lightweight and efficient tool for identification of short peptides.

Short peptides have become the focus of recent research due to their variable bioactivities, good digestibility and wide existences in food-derived protein hydrolysates. However, due to the high complexity of the samples, identifying short peptides still remains a challenge. In this work, a tool, named PeposX-Exhaust, was developed for short peptide identification. Through validation with known peptides, PeposX-Exhaust identified all the submitted spectra and the accuracy rate reached 75.36%, and the adjusted accuracy rate further reached 98.55% when with top 5 candidates considered. Compared with other tools, the accuracy rate by PeposX-Exhaust was at least 70% higher than two database-search tools and 15% higher than the other two de novo-sequencing tools, respectively. For further application, the numbers of short peptides identified from soybean, walnut, collagen and bonito protein hydrolysates reached 1145, 628, 746 and 681, respectively. This fully demonstrated the superiority of the tool in short peptide identification.

Changing the ionic strength can regulate the resistant starch content of binary complex including starch and protein or its hydrolysates.

Ionic strength condition is a crucial parameter for food processing, but it remains unclear how ionic strength alters the structure and digestibility of binary complexes containing starch and protein/protein hydrolysates. Here, the binary complex with varied ionic strength (0-0.40 M) was built by native corn starch (NS) and soy protein isolate (SPI)/hydrolysates (SPIH) through NaCl. The inclusion of SPI and SPIH allowed a compact network structure, especially the SPIH with reduced molecule size, which enriched the resistant starch (RS) of NS-SPIH. Particularly, the higher ionic strength caused the larger nonperiodic structures and induced loosener network structures, largely increasing the possibility of amylase for starch digestion and resulting in a decreased RS content from 19.07 % to 15.52 %. In other words, the SPIH hindered starch digestion while increasing ionic strength had the opposite effect, which should be considered in staple food production.

Use of olive and sunflower protein hydrolysates for the physical and oxidative stabilization of fish oil-in-water emulsions.

BACKGROUND: Olive and sunflower seeds are by-products generated in large amounts by the plant oil industry. The technological and biological properties of plant-based substrates, especially protein hydrolysates, have increased their use as functional ingredients for food matrices. The present study evaluates the physical and oxidative stabilities of 50 g kg-1 fish oil-in-water emulsions where protein hydrolysates from olive and sunflower seeds were incorporated at 20 g kg-1 protein as natural emulsifiers. The goal was to investigate the effect of protein source (i.e. olive and sunflower seeds), enzyme (i.e. subtilisin and trypsin) and degree of hydrolysis (5%, 8% and 11%) on the ability of the hydrolysate to stabilize the emulsion and retard lipid oxidation over a 7-day storage period. RESULTS: The plant protein hydrolysates displayed different emulsifying and antioxidant capacities when incorporated into the fish oil-in-water emulsions. The hydrolysates with degrees of hydrolysis (DH) of 5%, especially those from sunflower seed meal, provided higher physical stability, regardless of the enzymatic treatment. For example, the average D [2, 3] values for the emulsions containing sunflower subtilisin hydrolysates at DH 5% only slightly increased from 1.21 ± 0.02 µm (day 0) to 2.01 ± 0.04 µm (day 7). Moreover, the emulsions stabilized with sunflower or olive seed hydrolysates at DH 5% were stable against lipid oxidation throughout the storage experiment, with no significant variation in the oxidation indices between days 0 and 4. CONCLUSION: The results of the present study support the use of sunflower seed hydrolysates at DH 5% as natural emulsifiers for fish oil-in-water emulsions, providing both physical and chemical stability against lipid oxidation. © 2024 Society of Chemical Industry.