Relation of amino acid composition, hydrophobicity, and molecular weight with antidiabetic, antihypertensive, and antioxidant properties of mixtures of corn gluten and soy protein hydrolysates

Functional chia (Salvia hispanica L.) co-product protein hydrolysate: An analysis of biochemical, antidiabetic, antioxidant potential and physicochemical properties

Protein hydrolysates with antioxidant potential have been reported to act as adjuvants in preventing and treating type-2 diabetes (T2D). This work investigated the biochemical, antidiabetic, antioxidant potential, and physicochemical properties of chia meal protein hydrolysate (CMPH). Bands smaller than 14 kDa were observed in the electrophoretic profile. The predominant amino acids were hydrophobic and aromatic. CMPH had the potential to inhibit α-amylase (IC50: 1.76 ± 0.13 mg/mL), α-glucosidase (IC50: 0.42 ± 0.13 mg/mL), and DPP-IV (IC50: 0.46 ± 0.14 mg/mL). Antioxidant activity for ABTS (IC50: 0.236 mg/mL), DPPH (8.83 ± 0.52%), and ORAC (IC25: 0.115 mg/mL). Against chia meal protein isolate (CMPI), CMPH has a broad solubility (pH 2-12.46). Particle size (624.5 ± 247.3 nm), low PDI (0.22 ± 0.06), ζ-potential (-31.1 ± 2.5 mV), and surface hydrophobicity (11,183.33 ± 2024.11) and the intrinsic fluorescence peak of CMPH was lower than that of CMPI. CMPH represents an alternative to add value to the agri-food co-product of the chia seed oil industry, generating food ingredients with outstanding antidiabetic and antioxidant potential.

The relationship between the secondary structure and the emulsifying ability of protein-based particles and the Pickering emulsions stabilized by the zein-lysine complex

Due to the sustainability and widespread use of proteins, protein-based materials are extensively utilized in the preparation of Pickering emulsions. However, the relationship between the secondary structure of proteins and their emulsifying ability has not been further investigated. This study used the addition of three different amino acids to influence the interaction between zein chains, which may induce changes in the secondary structure of the prepared zein complex particles. This study demonstrates that the emulsifying properties of proteins, such as dispersibility, zeta potential, three-phase contact angles, interfacial affinity, adsorption rates, and the volume of the stabilized oil phase, are closely related to the β-sheet content of the complex particles, providing a theoretical reference for protein-based stabilizers. Additionally, amino acids, as the blocks of proteins, have high compatibility with proteins, and using amino acids as modifiers aligns with the safety requirements for food processing. In this study, the prepared zein-lysine complex particles have good emulsifying ability, capable of stabilizing a 50 (v/v)% emulsion at a lower concentration (10 mg mL-1), and the prepared emulsion exhibits high-temperature stability and ionic resistance. This characteristic makes the emulsion potentially valuable for application in systems with high salt concentrations and those that may undergo heat treatment.

Ultrasonication assisted enzymatic hydrolysis for generation of pulses protein hydrolysate having antioxidant and ACE-inhibitory activity

The main objective of this work was to investigate the impact of ultrasonication assisted enzymatic treatment on the physicochemical and bioactive properties of broad bean (BBP), lentil bean (LBP), and mung bean (MBP) protein isolates. The protein was extracted using alkaline acid precipitation method, ultrasonicated at a frequency of 20 kHz, temperature 20-30 °C and then hydrolysed using alcalase enzyme (1 % w/w, pH 8.5, 30 min, 55 οC). The generated hydrolysates were characterized by degree of hydrolysis (DH), SDS, FTIR, surface hydrophobicity, amino acid composition, antioxidant and antihypertensive properties. Results showed that the degree of hydrolysis was found to increase in ultrasonicated protein hydrolysate (18.9 to 40.71 %) in comparison to non- ultrasonicated protein hydrolysate (11 to 16.3 %). SDS-PAGE results showed significant changes in protein molecular weight profiles (100-11kDa) in comparison to their natives. However, no substantial change was found in ultrasonicated and non-ultrasonicated protein hydrolysates. The FTIR spectrum showed structural alterations in ultrasonicated and non-ultrasonicated protein hydrolysates, suggesting modifications in secondary structure such as amide A, amide I and amide II regions. The essential amino acid content varied in the range of 60.09 mg/g to 73.77 mg/g and 28.73 to 50.26 mg/g in case of ultrasonicated and non-ultrasonicated protein hydrolysates, and non-essential content varied in the range of 49.42 to 65.93 mg/g and 43.12 to 47.12 mg/g. Both antioxidant and antihypertensive activities were found to increase significantly in ultrasonicated and non-ultrasonicated protein hydrolysates in comparison to their native counterparts, highlighting their potential as functional ingredients for management of hypertension. It was concluded that ultrasonication assisted enzymatic hydrolysis is an efficient approach for production of bioactive pulse protein hydrolysates with enhanced nutracutical properties, thus offering promising avenues for their utilization in the food industry and beyond.

A Novel Workflow for In Silico Prediction of Bioactive Peptides: An Exploration of Solanum lycopersicum By-Products

Resource-intensive processes currently hamper the discovery of bioactive peptides (BAPs) from food by-products. To streamline this process, in silico approaches present a promising alternative. This study presents a novel computational workflow to predict peptide release, bioactivity, and bioavailability, significantly accelerating BAP discovery. The computational flowchart has been designed to identify and optimize critical enzymes involved in protein hydrolysis but also incorporates multi-enzyme screening. This feature is crucial for identifying the most effective enzyme combinations that yield the highest abundance of BAPs across different bioactive classes (anticancer, antidiabetic, antihypertensive, anti-inflammatory, and antimicrobial). Our process can be modulated to extract diverse BAP types efficiently from the same source. Here, we show the potentiality of our method for the identification of diverse types of BAPs from by-products generated from Solanum lycopersicum, the widely cultivated tomato plant, whose industrial processing generates a huge amount of waste, especially tomato peel. In particular, we optimized tomato by-products for bioactive peptide production by selecting cultivars like Line27859 and integrating large-scale gene expression. By integrating these advanced methods, we can maximize the value of by-products, contributing to a more circular and eco-friendly production process while advancing the development of valuable bioactive compounds.

Optimization of Enzymatic Hydrolysis by Protease Produced from Bacillus subtilis MTCC 2423 to Improve the Functional Properties of Wheat Gluten Hydrolysates

This study is aimed at investigating the reutilizing of gluten protein from the wheat processing industry by Bacillus subtilis MTCC 2423 protease to obtain gluten hydrolysates with high added value. Gluten protein hydrolysis using protease achieved a 34.07% degree of hydrolysis with 5% gluten protein, at a hydrolysis time of 2 h for 1000 U/mL at pH 8.0 and temperature of 40°C. Compared to the wheat gluten, the obtained hydrolysates exhibited enhanced functional attributes, including heightened solubility (43%), increased emulsifying activity (93.08 m2/g), and improved radical scavenging properties. Furthermore, these hydrolysates demonstrated enhanced antioxidant potential, as evidenced by elevated ABTS (2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) of 81.25% and DPPH (2,2-diphenyl-1-picrylhydrazyl) of 56.46% radical scavenging activities and also exhibited a higher α-amylase inhibitory effect of 33.98%. The enhancement in functional characteristics of wheat gluten hydrolysates was observed by Fourier transform infrared spectroscopy. The percentage of free amino acids obtained by protease-mediated hydrolysates increased significantly compared to the unhydrolyzed wheat, which was observed by high-performance liquid chromatography. These findings suggest that wheat gluten hydrolysates hold promising potential as functional and nutritional food ingredients in the food industry, owing to their enhanced functionalities and potential antioxidant and antidiabetic properties.

Antioxidant peptide nanohybrid: a new perspective to immobilize bioactive peptides from milk industry wastewater

In this study, dairy industry wastewater was collected and used as a protein source. The proteins were converted into powder form using lyophilization. The proteins were digested using Bacillus subtilis (B. subtilis) NCIM 2724. The maximum degree of hydrolysis (DH) of protein was observed at pH of 7, 30 °C incubation temperature, 120 rpm shaking speed, and 96 h incubation. The tris-glycine sodium dodecyl sulfate-polyacrylamide (tris-glycine-SDS) gel electrophoresis showed the disappearance of large molecular weight proteins due to the proteolytic action of B. subtilis. The resulting digest was fractionated using a 3 kDa membrane filter. The antioxidant activity of the obtained fractions was evaluated. Antioxidant activity of digest and filtrate was found to be 12.78% (±0.040) and 49% (±0.025), respectively, at a concentration of 50 mg/mL. The 3 kDa filtrate was subjected to liquid chromatography-mass spectrometry (LCMS) analysis. Bioinformatics tools were used to predict the sequences of antioxidant peptides. Furthermore, the 3 kDa filtrate was used for the synthesis of antioxidant nanohybrid. Scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS) confirmed the nanohybrid formation and encapsulation of peptides. The antioxidant nanohybrid showed enhanced antioxidant activity compared to the free peptide solution. The dairy industry has a significant environmental impact due to high water use and waste generation. This study addresses an important issue of recycling protein-containing wastewater and the potential to be used for converting these proteins into antioxidant peptides. Such practices will help to reduce environmental impact and sustainably operate the industry.

Optimization of fractionation with membranes of antioxidant enzymatic hydrolysate of Californian red worm (Eisenia fetida) protein

Problem

Earthworm is a valuable source of biologically and pharmacologically active compounds, with applications in the treatment of various types of diseases; however, the main application they have been given is in the production of organic fertilizer. One of the alternatives for obtaining bioactive compounds is by means of enzymatic hydrolysis.

Aim

This study proposes the optimization of the fractionation of the antioxidant enzymatic hydrolysate from Californian red worm (Eisenia fetida) protein.

Methodology

For this purpose, the worms were separated and hydrolyzed using the enzyme Alcalase 2.4L for 4000s. The obtained hydrolysate was fractionated by means of a crossflow tangential ultrafiltration system, with a 3 kDa molecular weight cut-off ceramic membrane. A response surface design of the composite central factorial type was implemented to evaluate the effect of pH, transmembrane pressure, and flow factors on the response variables transmission, volume reduction factor (VRF) and permeate flow resistance. The transmissions focused on the antioxidant peptides, measured by three conventional methods such as TEAC, FRAP, ORAC, also known as TTEAC, TFRAP and TORAC, respectively. The evaluated resistances were the total resistance (Rtotal), fouling resistance (Rfouling), and gel resistance (Rgel).

Result

The results showed that the three factors evaluated affect all the response variables either in their linear or quadratic terms or by some interaction. For each response variable, a mathematical model was obtained, with statistical significance and a non-significant lack of adjustment. The models obtained were used for a multi-objective optimization process in which transfers were maximized, and resistances were minimized. The efficiency of the optimum ultrafiltration process was 25 %.

Conclusion

The neutral-alkaline pH is ideal for the ultrafiltration process of bioactive peptides, as it is where the highest transmissions of peptides with antioxidative capacity are found. Under optimal conditions, the 3 kDa membrane permeate was found to exhibit higher antioxidant capacity than the retentate and feed. Based on this, the fraction of less than 3 kDa emerges as a potential multifunctional ingredient, thanks to its antioxidant properties.

Unlocking the Therapeutic Potential of a Manila Clam-Derived Antioxidant Peptide: Insights into Mechanisms of Action and Cytoprotective Effects against Oxidative Stress

Reactive oxygen species (ROS) are implicated in various pathological conditions due to their ability to induce oxidative damage to cellular components. In this study, we investigated the antioxidant properties of a peptide isolated from the hydrolysate of Manila clam (Ruditapes philippinarum) muscle. Purification steps yielded RPTE2-2-4, exhibiting potent scavenging activities against DPPH•, HO•, and O2•-, akin to Vitamin C. Structural analysis showed that the isolated peptide, LFKKNLLTL, exhibited characteristics associated with antioxidant activity, including a short peptide length and the presence of aromatic and hydrophobic amino acid residues. Moreover, our study demonstrated the cytoprotective effects of the peptide against H2O2-induced oxidative stress in HepG2 cells. Pretreatment with the peptide resulted in a dose-dependent reduction in intracellular ROS levels and elevation of glutathione (GSH) levels, indicating its ability to modulate cellular defense mechanisms against oxidative damage. Furthermore, the peptide stimulated the expression of the cytoprotective enzyme heme oxygenase-1 (HO-1), further reinforcing its antioxidant properties. Overall, our findings highlight the potential of the Manila clam-derived peptide as a natural antioxidant agent with therapeutic implications for oxidative stress-related diseases. Further investigation into its mechanisms of action and in vivo efficacy is warranted to validate its therapeutic potential.

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).

Compound collagen peptide powder improves skin photoaging by reducing oxidative stress and activating TGF-β1/Smad pathway

Fish collagen peptide (FCP) has been extensively investigated as a natural product that can combat photoaging; however, its efficacy is limited by its singular composition. Compound collagen peptide powder (CCPP) is a novel functional food formulation that exhibits photoprotective properties and comprises FCP and a blend of natural botanical ingredients. The objective of this study was to investigate the efficacy of CCPP and its molecular mechanism. CCPP had a low molecular weight, facilitating its efficient absorption, and was abundant in amino acids, total polyphenols, and total flavonoids. The results of in vivo studies demonstrated that CCPP exhibited significant efficacy in reducing skin wrinkles, enhancing the contents of water and oil in the skin, and ameliorating histopathological alterations in mice. The results of in vitro studies demonstrated that CCPP effectively mitigated photoaging in human skin fibroblasts by attenuating oxidative stress and promoting extracellular matrix (ECM) synthesis. Moreover, we clearly demonstrated that the TGF β1/Smad pathway was involved in the promotion of ECM synthesis and cell proliferation by CCPP in human skin fibroblasts. These findings suggest that, compared with single collagen, CCPP has a more comprehensive range of antiphotoaging properties.

In vitro, ex vivo and in vivo antihypertensive evaluation of enzymatic hydrolysates of Californian red worm (Eisenia fetida) proteins

Hypertension is an important risk factor concomitant with cardiovascular disease (CVD) states, which is why we set out to evaluate Californian red worm hydrolysates on antihypertensive activity both in vitro, ex vivo, using rabbit aortic rings and in vivo using hypertensive induced rats. The worms were manually separated, washed with water, purged for 4 h with 4 % sodium bicarbonate, sacrificed with 7 % saline, and finally washed with drinking water. The in vitro antihypertensive capacity was performed by measuring angiotensin-converting enzyme inhibition; for the ex vivo assays, rabbit aorta was used to measure relaxation; for the in vivo assays, rats with induced hypertension were used to perform acute (hypotension) and chronic assays, using captopril as a control in all assays. With respect to angiotensin-converting enzyme (ACE) inhibition, the EC50 value of the worm hydrolysate was found to be 358 ppm; with respect to the analysis in aortic rings, it was found that the mechanisms of action of the hydrolysate are endothelium-dependent, presenting a maximum relaxation of 35 %. With respect to the in vivo assays, the hypotensive test showed that the hydrolysate can reduce blood pressure by up to 32 % in only 2 h, while the chronic analysis showed that the hydrolysate at 150 ppm did not present statistically significant differences with the control (captopril) during the 15 days of analysis. The Red Californian earthworm hydrolysate presents bioactive compounds identified with antihypertensive activities in vitro, ex vivo and in vivo in different isolated and animal models. The study demonstrates the efficacy of the hydrolysate to be used as an alternative in the treatment and prevention of hypertension, and it can be implemented in functional foods or nutraceutical foods. Antihypertensive peptides, particularly those that inhibit angiotensin-converting enzyme (ACE), hold significant importance in medical research, specifically in the context of cardiovascular disease treatment, particularly hypertension. The focus on these peptides and the potential implications of their results in medical research can be summarized through several key points: 1) Mechanisms of Action-Antihypertensive peptides function by inhibiting ACE or renin, crucial enzymes in blood pressure regulation. 2)Alternatives to Synthetic Drugs, 3) Additional Health Benefits, and various other factors.

Development of lentil peptides with potent antioxidant, antihypertensive, and antidiabetic activities along with umami taste

Lentil peptides have shown promising bioactive properties regarding the antioxidant activity and also inhibitory activity of angiotensin-I-converting enzyme (ACE). Sequential hydrolysis of proteins has shown a higher degree of hydrolysis with enhanced antioxidant and ACE-inhibitory activities. The lentil protein concentrate (LPC) was sequentially hydrolyzed using Alcalase and Flavourzyme at 2% w/w. The hydrolysate (LPH) was cross-linked (LPHC) or sonicated (LPHUS) and sequentially cross-linked (LPHUSC). Amino acid profile, molecular weight (MW) distribution, DPPH and ABTS radical scavenging activities (RSA; 7 mg/mL), ACE (0.1-2 mg/mL), α-glucosidase, and α-amylase inhibitory activities (10-500 μg/mL), and umami taste were determined. The highest DPPH RSA was obtained for LPH (68.75%), followed by LPHUSC (67.60%), and LPHUS (67.49%) while the highest ABTS RSA values were obtained for LPHC (97.28%) and LPHUSC (97.20%). Cross-linking and sonication led to the improvement of the ACE-inhibitory activity so that LPHUSC and LPHC had IC50 values of 0.23 and 0.27 mg/mL, respectively. LPHC and LPHUSC also indicated higher α-glucosidase inhibitory activity (IC50 of 1.2 and 1.23 mg/mL) compared to LPH (IC50 of 1.74 mg/mL) and LPHUS (IC50 of 1.75 mg/mL) while the IC50 value of acarbose indicated 0.51 mg/mL. Moreover, LPHC and LPHUSC exhibited higher α-amylase inhibitory activities (IC50 of 1.35 and 1.16 mg/mL) than LPHUS (IC50 of 1.95 mg/mL), and LPH (IC50 of 2.51 mg/mL) while acarbose had an IC50 value of 0.43 mg/mL. Umami taste analysis revealed that LPH and LPHC due to MW of 1.7 and 2.3 kDa and also high umami amino acids could be well considered as representative of meaty and umami analog flavors while indicating stronger antioxidant, antihypertension, and antidiabetic attributes.