Integrated approach for obtaining bioactive peptides from whey proteins hydrolysed using a new proteolytic lactic acid bacteria

Whey proteins as multifunctional food materials: Recent advancements in hydrolysis, separation, and peptidomimetic approaches

Whey protein derived bioactives, including α-lactalbumin, ß-lactoglobulin, bovine serum albumin, lactoferrin, transferrin, and proteose-peptones, have exhibited wide ranges of functional, biological and therapeutic properties varying from anticancer, antihypertensive, and antimicrobial effects. In addition, their functional properties involve gelling, emulsifying, and foaming abilities. For these reasons, this review article is framed to understand the relationship existed in between those compound levels and structures with their main functional, biological, and therapeutic properties exhibited either in vitro or in vivo. The impacts of hydrolysis mechanism and separation techniques in enhancing those properties are likewise discussed. Furthermore, special emphasize is given to multifunctional effects of whey derived bioactives and their future trends in ameliorating further food, pharmaceutical, and nutraceutical products. The underlying mechanism effects of those properties are still remained unclear in terms of activity levels, efficacy, and targeted effectiveness. For these reasons, some important models linking to functional properties, thermal properties and cell circumstances are established. Moreover, the coexistence of radical trapping groups, chelating groups, sulfhydryl groups, inhibitory groups, and peptide bonds seemed to be the key elements in triggering those functions and properties. Practical Application: Whey proteins are the byproducts of cheese processing and usually the exploitation of these food waste products has increasingly getting acceptance in many countries, especially European countries. Whey proteins share comparable nutritive values to milk products, particularly on their richness on important proteins that can serve immune protection, structural, and energetic roles. The nutritive profile of whey proteins shows diverse type of bioactive molecules like α-lactalbumin, ß-lactoglobulin, lactoferrin, transferrin, immunoglobulin, and proteose peptones with wide biological importance to the living system, such as in maintaining immunological, neuronal, and signaling roles. The diversification of proteins of whey products prompted scientists to exploit the real mechanisms behind of their biological and therapeutic effects, especially in declining the risk of cancer, tumor, and further complications like diabetes type 2 and hypertension risk effects. For these reasons, profiling these types of proteins using different proteomic and peptidomic approaches helps in determining their biological and therapeutic targets along with their release into gastrointestinal tract conditions and their bioavailabilities into portal circulation, tissue, and organs. The wide applicability of those protein fractions and their derivative bioactive products showed significant impacts in the field of emulsion and double emulsion stabilization by playing roles as emulsifying, surfactant, stabilizing, and foaming agents. Their amphoteric properties helped them to act as excellent encapsulating agents, particularly as vehicle for delivering important vitamins and bioactive compounds. The presence of ferric elements increased their transportation to several metal-ions in the same time increased their scavenging effects to metal-transition and peroxidation of lipids. Their richness with almost essential and nonessential amino acids makes them as selective microbial starters, in addition their richness in sulfhydryl amino acids allowed them to act a cross-linker in conjugating further biomolecules. For instance, conjugating gold-nanoparticles and fluorescent materials in targeting diseases like cancer and tumors in vivo is considered the cutting-edges strategies for these versatile molecules due to their active diffusion across-cell membrane and the presence of specific transporters to these therapeutic molecules.

Antitumor activity of a whey peptide-based enteral diet in C26 colon tumor-bearing mice

The antitumor effects of a whey peptide-based enteral diet, whose main components are whey peptides and yogurt fermented by Lactobacillus delbureckii subsp. bulgaricus 2038 and Streptococcus thermophilus 1131, were investigated in mice. Our results indicated that the tumor weight in C26 carcinoma-transplanted mice was significantly smaller at day 16 post-implantation in the whey peptide-based enteral diet group (1.36 ± 0.54 g) than in the control group (1.83 ± 0.89 g) (p < 0.05). The whey peptide-based enteral diet group exhibited higher tumor cell apoptosis, lower cell proliferation, and inactive angiogenesis indicating by higher degree of TUNEL, lower positive rates of Ki-67, VEGF, and CD34 than control group. It also attenuated inflammatory cell infiltration of spleen and liver as indicated by the decreased spleen index (10.89 ± 2.06 vs. 12.85 ± 2.92, p < 0.05) and increased liver index (58.09 ± 11.37 vs. 53.19 ± 6.67, p < 0.05) in the whey peptide-based enteral diet group than the control diet group. These results proved the inhibitory effect of the whey peptide-based enteral diet on tumor growth, which might be attributed to the whey peptides component. PRACTICAL APPLICATION: A whey peptide-based enteral diet (MEIN® ), containing cheese whey and multiple nutrients, was selected to verify the anti-tumor effect by animal experiments. The tumor weight growth, tumor cell proliferation, inflammatory cell infiltration of spleen and liver in tumor model mice was significantly attenuated by the whey peptide-based enteral diet, that might be attributed to its whey peptides component. These results provided an additive direction for cancer therapy and need a further study including clinical trials.

Effect of preserved eggs on the health of SD rats, and anti-tumor action of HT-29 cells

Preserved eggs are traditional alkali-pickled food in China and have been enjoyed by consumers and extensively studied by researchers for their nutritional tastes and their anti-tumor, anti-inflammatory, antioxidant, lipid-lowering, and blood pressure-lowering properties. To study the anti-tumor effects of preserved eggs, this project observed the health on rats, and anti-tumor effects and separated anti-tumor active components on HT-29 cells. SD rats fed for 80 days showed that preserved eggs had no significant effect on weight, food intake, blood pH, liver tissues, or organ indices. Preserved eggs significantly increased blood levels of oxidative stress markers SOD and CAT, decreased MDA levels by 0.46, 0.23, and 0.25 times. Moreover, they also increased the level of IL-2 from 1233 to 1340 pg/mL. Two water-soluble bioactive peptide fractions, B1 and B2, with molecular weights ≥10 kDa were further obtained from preserved eggs by ultrafiltration and Superdex Peptide 10/300 GL. The potential mechanism of B1 and B2 is to activate the internal mitochondrial apoptotic pathway and induce apoptosis by up-regulating the expression of the pro-apoptotic factors cytochrome C, caspase-3, and caspase-9 mRNA in HT-29 cells.

Probiotic therapy, African fermented foods and food-derived bioactive peptides in the management of SARS-CoV-2 cases and other viral infections

The current paper focuses on the impact of probiotics, African fermented foods and bioactive peptides on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection severity and related viral infections. Using probiotics or bioactive peptides as therapeutic adjuncts appears superior to standard care alone. Probiotics play critical roles in innate and adaptive immune modulation by balancing the gut microbiota to combat viral infections, secondary bacterial infections and microbial dysbiosis. African fermented foods contain abundant potential probiotic microorganisms such as the lactic acid bacteria (LAB), Saccharomyces, and Bacillus. More so, fermented food-derived bioactive peptides play vital roles in preventing cardiovascular diseases, hypertension, lung injury, diabetes, and other COVID-19 comorbidities. Regularly incorporating potential probiotics and bioactive peptides into diets should enable a build-up of the benefits in the body system that may result in a better prognosis, especially in COVID-19 patients with underlying complexities. Despite the reported therapeutic potentials of probiotics and fermented foods, numerous setbacks exist regarding their application in disease management. These shortfalls underscore an evident need for more studies to evaluate the specific potentials of probiotics and traditional fermented foods in ameliorating SARS-CoV-2 and other viral infections.

Food Peptides for the Nutricosmetic Industry

In recent years, numerous reports have described bioactive peptides (biopeptides)/hydrolysates produced from various food sources. Biopeptides are considered interesting for industrial application since they show numerous functional properties (e.g., anti-aging, antioxidant, anti-inflammatory, and antimicrobial properties) and technological properties (e.g., solubility, emulsifying, and foaming). Moreover, they have fewer side effects than synthetic drugs. Nevertheless, some challenges must be overcome before their administration via the oral route. The gastric, pancreatic, and small intestinal enzymes and acidic stomach conditions can affect their bioavailability and the levels that can reach the site of action. Some delivery systems have been studied to avoid these problems (e.g., microemulsions, liposomes, solid lipid particles). This paper summarizes the results of studies conducted on biopeptides isolated from plants, marine organisms, animals, and biowaste by-products, discusses their potential application in the nutricosmetic industry, and considers potential delivery systems that could maintain their bioactivity. Our results show that food peptides are environmentally sustainable products that can be used as antioxidant, antimicrobial, anti-aging, and anti-inflammatory agents in nutricosmetic formulations. Biopeptide production from biowaste requires expertise in analytical procedures and good manufacturing practice. It is hoped that new analytical procedures can be developed to simplify large-scale production and that the authorities adopt and regulate use of appropriate testing standards to guarantee the population's safety.

Bioactive Antimicrobial Peptides from Food Proteins: Perspectives and Challenges for Controlling Foodborne Pathogens

Bioactive peptides (BAPs) derived from food proteins have been extensively studied for their health benefits, majorly exploring their potential use as nutraceuticals and functional food components. These peptides possess a range of beneficial properties, including antihypertensive, antioxidant, immunomodulatory, and antibacterial activities, and are naturally present within dietary protein sequences. To release food-grade antimicrobial peptides (AMPs), enzymatic protein hydrolysis or microbial fermentation, such as with lactic acid bacteria (LAB), can be employed. The activity of AMPs is influenced by various structural characteristics, including the amino acid composition, three-dimensional conformation, liquid charge, putative domains, and resulting hydrophobicity. This review discusses the synthesis of BAPs and AMPs, their potential for controlling foodborne pathogens, their mechanisms of action, and the challenges and prospects faced by the food industry. BAPs can regulate gut microbiota by promoting the growth of beneficial bacteria or by directly inhibiting pathogenic microorganisms. LAB-promoted hydrolysis of dietary proteins occurs naturally in both the matrix and the gastrointestinal tract. However, several obstacles must be overcome before BAPs can replace antimicrobials in food production. These include the high manufacturing costs of current technologies, limited in vivo and matrix data, and the difficulties associated with standardization and commercial-scale production.

Impact of Spontaneous Fermentation and Inoculum with Natural Whey Starter on Peptidomic Profile and Biological Activities of Cheese Whey: A Comparative Study

Fermentation is a promising solution to valorize cheese whey, the main by-product of the dairy industry. In Parmigiano Reggiano cheese production, natural whey starter (NWS), an undefined community of thermophilic lactic acid bacteria, is obtained from the previous day residual whey through incubation at gradually decreasing temperature after curd cooking. The aim of this study was to investigate the effect of fermentation regime (spontaneous (S) and NWS-inoculated (I-NWS)) on biofunctionalities and release of bioactive peptides during whey fermentation. In S and I-NWS trials proteolysis reached a peak after 24 h, which corresponded to the drop out in pH and the maximum increase in lactic acid. Biological activities increased as a function of fermentation time. NWS inoculum positively affected antioxidant activity, whilst S overcame I-NWS in angiotensin-converting enzyme (ACE) and DPP-IV (dipeptidyl peptidase IV) inhibitory activities. Peptidomics revealed more than 400 peptides, mainly derived from β-casein, κ-casein, and α-lactalbumin. Among them, 49 were bioactive and 21 were ACE-inhibitors. Semi-quantitative analysis strongly correlated ACE-inhibitory activity with the sum of the peptide abundance of ACE-inhibitory peptides. In both samples, lactotripeptide isoleucine-proline-proline (IPP) was higher than valine-proline-proline (VPP), with the highest content in S after 24 h of fermentation. In conclusion, we demonstrated the ability of whey endogenous microbiota and NWS to extensively hydrolyze whey proteins, promoting the release of bioactive peptides and improving protein digestibility.

Tandem mass tag-based quantitative proteomics analysis reveals the effects of the α-lactalbumin peptides GINY and DQW on lipid deposition and oxidative stress in HepG2 cells

The objective of this study was to investigate the mechanism by which the α-lactalbumin peptides Gly-Ile-Asn-Tyr (GINY) and Asp-Gln-Trp (DQW) ameliorate free fatty acid-induced lipid deposition in HepG2 cells. The results show that GINY and DQW reduced triglyceride, total cholesterol, and free fatty acid levels significantly in free fatty acid-treated HepG2 cells. Based on proteomic analysis, GINY and DQW alleviated lipid deposition and oxidative stress mainly through the peroxisome proliferator-activated receptor (PPAR) pathway, fatty acid metabolism, oxidative phosphorylation, and response to oxidative stress. In vitro experiments confirmed that GINY and DQW upregulated the mRNA and protein expression of fatty acid β-oxidation-related and oxidative stress-related genes, and downregulated the mRNA and protein expression of lipogenesis-related genes by activating peroxisome proliferator-activated receptor α (PPARα). Meanwhile, GINY and DQW reduced free fatty acid-induced lipid droplet accumulation and reactive oxygen species generation, and enhanced the mitochondrial membrane potential and ATP levels. Furthermore, GINY and DQW enhanced carnitine palmitoyl-transferase 1a (CPT-1a) and superoxide dismutase activities, and diminished acetyl-coenzyme A carboxylase 1 (ACC1) and fatty acid synthase (FASN) activities in a PPARα-dependent manner. Interestingly, GW6471 (a PPARα inhibitor) weakened the effects of GINY and DQW on the PPARα pathway. Hence, our findings suggest that GINY and DQW have the potential to alleviate nonalcoholic fatty liver disease by activating the PPARα pathway.

Effects of probiotics on hypertension

Emerging data have suggested that probiotics had good potential in regulating intestinal flora and preventing hypertension. Some studies in human and animal models have demonstrated probiotic intervention could attenuate hypertension, regulate intestinal flora to increase the abundance of beneficial bacteria, and regulate intestinal microbial metabolites such as trimethylamine oxide, short-chain fatty acids, and polyphenols. However, there is still some debate as to whether probiotics exert effective benefits. These recently published reviews did not systematically expound on the heterogeneity between the effect and mechanism of probiotics with different types, doses, and carriers to exert antihypertensive effects, as well as the possible application of probiotics in the prevention and treatment of hypertension in food and clinic. Here we try to systematically review the association between hypertension and intestinal microflora, the effect of probiotics and their metabolites on hypertension, and the recent research progress on the specific mechanism of probiotics on hypertension. In addition, we also summarized the potential application of probiotics in antihypertension. Future challenges include elucidating the functions of metabolites produced by microorganisms and their downstream pathway or molecules, identifying specific strains, not just microbial communities, and developing therapeutic interventions that target hypertension by modulation of gut microbes and metabolites.

Purification of Extracellular Protease from Staphylococcus simulans QB7and Its Ability in Generating Antioxidant and Anti-inflammatory Peptides from Meat Proteins

Proteases, especially microbial proteases, are widely used in food processing. The purpose of this study was aimed to purify an extracellular protease produced by the strain Staphylococcus simulans QB7 and to evaluate its ability in hydrolyzing meat proteins and generating antioxidant and anti-inflammatory peptides. The optimal conditions for producing the enzyme were as follows: inoculum ratio, 10%; initial pH, 6.5; temperature, 32 °C; incubation time, 36 h; and rotation speed, 160 rpm. The protease had a molecular weight of approximately 47 kDa, possessing the optimal activity at 50 °C, pH 7.0, The protease was stable at pH 4.0-8.0 and 30-60 °C, and the activity was improved by Na⁺, Mg²⁺, Ca²⁺, and Zn²⁺ ions, whereas it was inhibited by Cu²⁺, Co²⁺, Fe³⁺, Ba²⁺, Fe²⁺, β-M, and ethylene diamine tetraacetic acid disodium salt (EDTA). The protease could effectively hydrolyze meat proteins, and the generated hydrolysate could significantly inhibit tumor necrosis factor-alpha (TNFα)-induced oxidative stress, including superoxide and malondialdehyde levels and inflammation (vascular adhesion molecule-1 [VCAM-1] and cyclooxygenase 2 [COX2)) in human vascular EA.hy926 cells. The present findings support the ability of S. simulans QB7 protease in generating antioxidant and anti-inflammatory peptides during the fermentation of meat products.

Peptidomics-based identification of an antimicrobial peptide derived from goat milk fermented by Lactobacillus rhamnosus (C25)

Antimicrobial peptides (AMPs) are emerging as promising novel drug applicants. In the present study, goat milk was fermented using Lactobacillus rhamnosus C25 to generate bioactive peptides (BAPs). The peptide fractions generated were separated using ultrafiltration membranes with molecular weight cut-offs of 3, 5, and 10 kDa, and their antimicrobial activity toward Gram-positive and Gram-negative bacteria was investigated. Isolated AMPs were characterized using RP-HPLC and identified by LC-MS/MS. A total of 569 sequences of peptides were identified by mass spectrometry. Out of the 569, 36 were predicted as AMPs, 21 were predicted as cationic, and out of 21, 6 AMPs were helical peptides. In silico analysis indicated that the majority of peptides were antimicrobial and cationic in nature, an important factor for peptide interaction with the negative charge membrane of bacteria. The results showed that the peptides of <5 kDa exhibited maximum antibacterial activity against E. faecalis, E. coli, and S. typhi. Further, molecular docking was used to evaluate the potent MurD ligase inhibitors. On the basis of ligand binding energy, six predicted AMPs were selected and then analyzed by AutoDock tools. Among the six AMPs, peptides IGHFKLIFSLLRV (-7.5 kcal/mol) and KSFCPAPVAPPPPT (-7.6 kcal/mol), were predicted as a high-potent antimicrobial. Based on these findings, in silico investigations reveal that proteins of goat milk are a potential source of AMPs. This is for the first time that the antimicrobial peptides produced by Lactobacillus rhamnosus (C25) fermentation of goat milk have been identified via LC-MS/MS and predicted as AMPs, cationic charges, helical structure in nature, and potent MurD ligase inhibitors. These peptides can be synthesized and improved for use as antimicrobial agents. PRACTICAL APPLICATIONS: Goat milk is considered a high-quality source of milk protein. According to this study, goat milk protein is a potential source of AMPs, Fermentation can yield goat milk-derived peptides with a broad antibacterial activity spectrum at a low cost. The approach described here could be beneficial in that the significant AMPs can be synthesized and used in the pharmaceutical and food industries.

Use of Bacteriocins and Bacteriocinogenic Beneficial Organisms in Food Products: Benefits, Challenges, Concerns

This review’s objective was to critically revisit various research approaches for studies on the application of beneficial organisms and bacteriocins as effective biopreservatives in the food industry. There are a substantial number of research papers reporting newly isolated bacterial strains from fermented food products and their application as potential probiotics, including partial characterization of bacteriocins produced by these microorganisms. Most of these studies follow scientific community-accepted standard procedures and propose various applications of the studied strains and bacteriocins as potential biopreservatives for the food industry. A few investigations go somewhat further, performing model studies, exploring the application of expressed bacteriocins in a designed food product, or trying to evaluate the effectiveness of the studied potential probiotics and bacteriocins against foodborne pathogens. Some authors propose applications of bacteriocin producers as starter cultures and are exploring in situ bacteriocin production to aid in the effective control of foodborne pathogens. However, few studies have evaluated the possible adverse effects of bacteriocins, such as toxicity. This comes from well-documented reports on bacteriocins being mostly non-immunogenic and having low cytotoxicity because most of these proteinaceous molecules are small peptides. However, some studies have reported on bacteriocins with noticeable cytotoxicity, which may become even more pronounced in genetically engineered or modified bacteriocins. Moreover, their cytotoxicity can be very specific and is dependent on the concentration of the bacteriocin and the nature of the targeted cell. This will be discussed in detail in the present review.

Antioxidant and immunomodulatory potency of Lacticaseibacillus rhamnosus NCDC24 fermented milk-derived peptides: A computationally guided in-vitro and ex-vivo investigation

Infections of microbial and non-microbial origins have been associated with significant immunological manifestations, thereby underscoring the need for a thorough understanding and investigation of novel immunomodulatory and antioxidant molecules that could prevent these incidences. To this end, we herein aim to identify fermented milk peptides with antioxidant and immunomodulatory properties that could be exploited for specific future applications. Our computational prediction models indicate that these peptides are non-toxic and possess considerable hydrophobicity (19.82-38.96 %) and functionality. Further analyses reveal that two of the four peptides, i.e., Pep 1 (AGWNIPM) and Pep 4 (YLGYLEQLLR), possess higher in-vitro antioxidant activity. The immunomodulatory potential of these two peptides (Pep 1 and Pep 4) is further demonstrated by using a combination of molecular simulation trajectory and ex-vivo approaches. Both peptides demonstrate ability to control the production of pro- inflammatory (TNF-α, IL-1, and IL-6) and anti-inflammatory (IL-10) cytokines as well as nitric oxide release in LPS-stimulated murine peritoneal macrophages. Similarly, peptide interferences also lead to significant (P < 0.05) improvement in macrophage phagocytic capacity. Taken together, these findings highlight the antioxidant and immunomodulatory properties of fermented milk peptides (Pep 1 and Pep 4) within the cellular environment and should facilitate prospective studies exploring such bioactive peptides and related functional molecules mediating the benefits of fermented milk products on human health.

Health-Promoting and Therapeutic Attributes of Milk-Derived Bioactive Peptides

Milk-derived bioactive peptides (BAPs) possess several potential attributes in terms of therapeutic capacity and their nutritional value. BAPs from milk proteins can be liberated by bacterial fermentation, in vitro enzymatic hydrolysis, food processing, and gastrointestinal digestion. Previous evidence suggested that milk protein-derived BAPs have numerous health-beneficial characteristics, including anti-cancerous activity, anti-microbial activity, anti-oxidative, anti-hypertensive, lipid-lowering, anti-diabetic, and anti-osteogenic. In this literature overview, we briefly discussed the production of milk protein-derived BAPs and their mechanisms of action. Milk protein-derived BAPs are gaining much interest worldwide due to their immense potential as health-promoting agents. These BAPs are now used to formulate products sold in the market, which reflects their safety as natural compounds. However, enhanced commercialization of milk protein-derived BAPs depends on knowledge of their particular functions/attributes and safety confirmation using human intervention trials. We have summarized the therapeutic potentials of these BAPs based on data from in vivo and in vitro studies.

Bioactive peptides of whey: obtaining, activity, mechanism of action, and further applications

Bioactive peptides derived from diverse food proteins have been part of diverse investigations. Whey is a rich source of proteins and components related to biological activity. It is known that proteins have effects that promote health benefits. Peptides derived from whey proteins are currently widely studied. These bioactive peptides are amino acid sequences that are encrypted within the first structure of proteins, which required hydrolysis for their release. The hydrolysis could be through in vitro or in vivo enzymatic digestion and using microorganisms in fermented systems. The biological activities associated with bio-peptides include immunomodulatory properties, antibacterial, antihypertensive, antioxidant and opioid, etc. These functions are related to general conditions of health or reduced risk of certain chronic illnesses. To determine the suitability of these peptides/ingredients for applications in food technology, clinical studies are required to evaluate their bioavailability, health claims, and safety of them. This review aimed to describe the biological importance of whey proteins according to the incidence in human health, their role as bioactive peptides source, describing methods, and obtaining technics. In addition, the paper exposes biochemical mechanisms during the activity exerted by biopeptides of whey, and their application trends.

Fate of Bioactive Compounds during Lactic Acid Fermentation of Fruits and Vegetables

Consumption of lactic acid fermented fruits and vegetables has been correlated with a series of health benefits. Some of them have been attributed to the probiotic potential of lactic acid microbiota, while others to its metabolic potential and the production of bioactive compounds. The factors that affect the latter have been in the epicenter of intensive research over the last decade. The production of bioactive peptides, vitamins (especially of the B-complex), gamma-aminobutyric acid, as well as phenolic and organosulfur compounds during lactic acid fermentation of fruits and vegetables has attracted specific attention. On the other hand, the production of biogenic amines has also been intensively studied due to the adverse health effects caused by their consumption. The data that are currently available indicate that the production of these compounds is a strain-dependent characteristic that may also be affected by the raw materials used as well as the fermentation conditions. The aim of the present review paper is to collect all data referring to the production of the aforementioned compounds and to present and discuss them in a concise and comprehensive way.

Influence of Culture Media Formulated with Agroindustrial Wastes on the Antimicrobial Activity of Lactic Acid Bacteria

The discarding of wastes into the environment is a significant problem for many communities. Still, food waste can be used for lactic acid bacteria (LAB) growth. Here, we evaluated three growth media equivalent to de Mann Rogosa Sharpe (MRS), using apple bagasse, yeast waste, fish flour, forage oats, and cheese whey. Cell-free supernatants of eight LAB strains were tested for antimicrobial activity against nine indicator microorganisms. The supernatants were also evaluated for protein content, reducing sugars, pH, and lactic acid concentration. Cell-free supernatants from fish flour broth (FFB) LAB growth were the most effective. The strain Leuconostoc mesenteroides PIM5 presented the best activity in all media. L. mesenteroides CAL14 completely inhibited L. monocytogenes and strongly inhibited Bacillus cereus (91.1%). The strain L. mesenteroides PIM5 consumed more proteins (77.42%) and reducing sugars (56.08%) in FFB than in MRS broth (51.78% and 30.58%, respectively). Culture media formulated with agroindustrial wastes positively improved the antimicrobial activity of selected LAB, probably due to the production of antimicrobial peptides or bacteriocins.

Exploring the DPP-IV Inhibitory, Antioxidant and Antibacterial Potential of Ovine "Scotta" Hydrolysates

The aim of this work was to valorize the by-product derived from the ricotta cheese process (scotta). In this study, ovine scotta was concentrated by ultrafiltration and then subjected to enzymatic hydrolyses using proteases of both vegetable (4% E:S, 4 h, 50 °C) and animal origin (4% E:S, 4 h, 40 °C). The DPP-IV inhibitory, antioxidant, and antibacterial activities of hydrolysates from bromelain (BSPH) and pancreatin (PSPH) were measured in vitro. Both the obtained hydrolysates showed a significantly higher DPP-IV inhibitory activity compared to the control. In particular, BSPH proved to be more effective than PSPH (IC₅₀ 8.5 ± 0.2 vs. 13 ± 1 mg mL⁻¹). Moreover, BSPH showed the best antioxidant power, while PSPH was more able to produce low-MW peptides. BSPH and PSPH hydrolysates showed a variable but slightly inhibitory effect depending on the species or strain of bacteria tested. BSPH and PSPH samples were separated by gel permeation chromatography (GPC). LC-MS/MS analysis of selected GPC fractions allowed identification of differential peptides. Among the peptides 388 were more abundant in BSPH than in the CTRL groups, 667 were more abundant in the PSPH group compared to CTRL, and 97 and 75 of them contained sequences with a reported biological activity, respectively.

Manufacturing of Plant-Based Bioactive Peptides Using Enzymatic Methods to Meet Health and Sustainability Targets of the Sustainable Development Goals

Due to the rapid growth in the global population, the consumption of animal-based food products/food compounds has been associated with negative implications for food sustainability/security. As a result, there is an increasing demand for the development of plant-based food and compounds as alternatives. Meanwhile, a growing number of studies report the health benefits of food protein-based peptides prepared via enzymatic hydrolysis and exhibiting biological properties such as antioxidant, antihypertensive, anti-thrombotic, and antidiabetic activities. However, the inherent bitterness of some peptides hinders their application in food products as ingredients. This article aims to provide the latest findings on plant-based bioactive peptides, particularly their health benefits, manufacturing methods, detection and qualification of their bitterness properties, as well as debittering methods to reduce or eliminate this negative sensory characteristic. However, there is still a paucity of research on the biological property of debittered peptides. Therefore, the role of plant protein-derived bioactive peptides to meet the health targets of the Sustainable Development Goals can only be realised if advances are made in the industrial-scale bioprocessing and debittering of these peptides.

Identification and characterization of antioxidant peptides obtained from the bioaccessible fraction of α-lactalbumin hydrolysate

Whey is an abundantand sustainable source of bioactive peptides obtained from cheese making process. Whey proteins such as α-lactalbumin can be biologically active when the bioactive peptides encrypted in the amino acid sequence of the native protein are released by enzymatic hydrolysis. In the present work, the identification, sequence analysis, and antioxidant activity of bioaccessible peptides from α-lactalbumin alcalase-hydrolysate was assessed. Antioxidant activity (ABTS, ORAC, and HORAC) of α-lactalbumin showed a significant increase (p < 0.05) after the enzymatic treatment with alcalase and this capacity increased even more after the simulation of the gastrointestinal digestion process. Peptides contained in the gastrointestinal digest of α-lactalbumin hydrolysate were separated by preparative RP-HPLC (55 fractions), and three peptides were identified by LC-MS/MS analysis from selected fractions: IWCKDDQNPH (MW: 1254.54 Da) f(59-68), KFLDDDLTDDIM (MW: 1439.64 Da) f(79-90), DKFLDDDLTDDIM (MW: 1554.67 Da) f(78-90). Among the chemically synthesized peptides, IWCKDDQNPH showed the highest antioxidant capacity determined by ORAC, ABTS, and HORAC assays (IC₅₀ 0.015 ± 0.002, 0.45 ± 0.02, and 1.30 ± 0.05 mg/ml, respectively) and this activity may be related to the amino acid sequence. This is the first report where these bioaccessible peptides from α-lactalbumin hydrolysate were identified. The α-lactalbumin hydrolysate could be employed as a functional antioxidant ingredient. PRACTICAL APPLICATION: The present work studied the bioaccessibility of antioxidant peptides from an α-lactalbumin alcalase-hydrolysate by identifying three novel bioaccessible peptides responsible for the antioxidant capacity, providing evidence of the hydrolysate potential as an antioxidant ingredient in the formulations of functional foods and/or food supplements.

Characteristics of Food Protein-Derived Antidiabetic Bioactive Peptides: A Literature Update

Diabetes, a glucose metabolic disorder, is considered one of the biggest challenges associated with a complex complication of health crises in the modern lifestyle. Inhibition or reduction of the dipeptidyl peptidase IV (DPP-IV), alpha-glucosidase, and protein-tyrosine phosphatase 1B (PTP-1B) enzyme activities or expressions are notably considered as the promising therapeutic strategies for the management of type 2 diabetes (T2D). Various food protein-derived antidiabetic bioactive peptides have been isolated and verified. This review provides an overview of the DPP-IV, PTP-1B, and α-glucosidase inhibitors, and updates on the methods for the discovery of DPP-IV inhibitory peptides released from food-protein hydrolysate. The finding of novel bioactive peptides involves studies about the strategy of separation fractionation, the identification of peptide sequences, and the evaluation of peptide characteristics in vitro, in silico, in situ, and in vivo. The potential of bioactive peptides suggests useful applications in the prevention and management of diabetes. Furthermore, evidence of clinical studies is necessary for the validation of these peptides’ efficiencies before commercial applications.

Characteristics of the Proteolytic Enzymes Produced by Lactic Acid Bacteria

Over the past several decades, we have observed a very rapid development in the biotechnological use of lactic acid bacteria (LAB) in various branches of the food industry. All such areas of activity of these bacteria are very important and promise enormous economic and industrial successes. LAB are a numerous group of microorganisms that have the ability to ferment sugars into lactic acid and to produce proteolytic enzymes. LAB proteolytic enzymes play an important role in supplying cells with the nitrogen compounds necessary for their growth. Their nutritional requirements in this regard are very high. Lactic acid bacteria require many free amino acids to grow. The available amount of such compounds in the natural environment is usually small, hence the main function of these enzymes is the hydrolysis of proteins to components absorbed by bacterial cells. Enzymes are synthesized inside bacterial cells and are mostly secreted outside the cell. This type of proteinase remains linked to the cell wall structure by covalent bonds. Thanks to advances in enzymology, it is possible to obtain and design new enzymes and their preparations that can be widely used in various biotechnological processes. This article characterizes the proteolytic activity, describes LAB nitrogen metabolism and details the characteristics of the peptide transport system. Potential applications of proteolytic enzymes in many industries are also presented, including the food industry.

Technical integrative approaches to cheese whey valorization towards sustainable environment

Whey, a byproduct of cheese production, is often treated as an industrial dairy waste. A large volume of this product is disposed of annually due to inadequate bioconversion approaches. With its high pollutant load, disposal without pretreatment has raised a lot of environmental concerns alerting the need to seek optimal methods for adequately extracting and utilizing its organic content. In recent years, several techniques for whey valorization have emerged which may serve as interventionary measures against its environmental effects after disposal. In this review, we discuss five major approaches, by which whey can be converted into eco-friendly products, to significantly cut whey wastage. The approaches to whey valorization are therefore examined under the following perspectives: whey as a raw material for the production of bioethanol and prebiotic oligosaccharides via β-galactosidase and microbe catalyzed reactions, for the production of refined lactose as an excipient for pharmaceutical purposes, and the clinical significance of whey hydrolysates and their antifungal activity in food processing.

Bioactive peptides from food fermentation: A comprehensive review of their sources, bioactivities, applications, and future development

Bioactive peptides (BPs) are specific protein fragments that exert various beneficial effects on human bodies and ultimately influence health, depending on their structural properties and amino acid composition and sequences. By offering promising solutions to solve diverse health issues, the production, characterization, and applications of food-derived BPs have drawn great interest in the current literature and are of particular interest to the food and pharmaceutical industries. The microbial fermentation of protein from various sources is indubitably a novel way to produce BPs with numerous beneficial health effects. Apart from its lower cost as compared to enzymes, the BPs produced from microbial fermentation can be purified without further hydrolysis. Despite these features, current literature shows dearth of information on the BPs produced from food via microbial fermentation. Hence, there is a strong necessity to explore the BPs obtained from food fermentation for the development of commercial nutraceuticals and functional foods. As such, this review focuses on the production of BPs from different food sources, including the extensively studied milk and milk products, with emphasis on microbial fermentation. The structure-activity (antihypertensive, antioxidant, antimicrobial, opiate-like, anti-inflammatory, anticancer/antiproliferative, antithrombotic, hypolipidemic, hypocholesterolemic, and mineral binding) relationship, potential applications, future development, and challenges of BPs obtained from food fermentation are also discussed.

Soybean (Glycine max) Protein Hydrolysates as Sources of Peptide Bitter-Tasting Indicators: An Analysis Based on Hybrid and Fragmentomic Approaches

The aim of this study was to analyze soybean proteins as sources of peptides likely to be bitter using fragmentomic and hybrid approaches involving in silico and in vitro studies. The bitterness of peptides (called parent peptides) was theoretically estimated based on the presence of bitter-tasting motifs, particularly those defined as bitter-tasting indicators. They were selected based on previously published multilinear stepwise regression results. Bioinformatic-assisted analyses covered the hydrolysis of five major soybean-originating protein sequences using bromelain, ficin, papain, and proteinase K. Verification of the results in experimental conditions included soy protein concentrate (SPC) hydrolysis, RP-HPLC (for monitoring the proteolysis), and identification of peptides using RP-HPLC-MS/MS. Discrepancies between in silico and in vitro results were observed when identifying parent peptide SPC hydrolysate samples. However, both analyses revealed that conglycinins were the most abundant sources of parent peptides likely to taste bitter. The compatibility percentage of the in silico and in vitro results was 3%. Nine parent peptides with the following sequences were identified in SPC hydrolysates: LSVISPK, DVLVIPLG, LIVILNG, NPFLFG, ISSTIV, PQMIIV, PFPSIL, DDFFL, and FFEITPEK (indicators are in bold). The fragmentomic idea of research might provide a supportive method for predicting the bitterness of hydrolysates. However, this statement needs to be confirmed experimentally.