Functional Food Industries Research Articles

Optimization of ultrasound-assisted extraction of phenolics from Cordia dichotoma leaves using response surface methodology

In this study, ultrasound-assisted extraction (UAE) was employed to extract phenolic compounds from Cordia dichotoma (C. Dichotoma) leaves. The extraction process was optimized using response surface methodology (RSM). The C. Dichotoma tree is found in tropical and subtropical areas and has medicinal properties. The obtained extracts were subjected to phytochemical screening using standard tests, antioxidant potential, and total phenolic content (TPC) of C. Dichotoma leaf extract by 2,2-diphenylpicrylhydrazyl assay and Folin-Ciocalteu assay respectively. The impact of process parameters like different solvents, solute-to-solvent ratio, ultrasonic power, and sonication time on TPC and antioxidant activity were studied. UAE offers a more rapid and efficient extraction process when compared to conventional extraction techniques such as Soxhlet extraction due to effective mass transfer. RSM models identified that ultrasonic power of 200 W and 30:1 (mL/g) solvent-to-solute ratio, using methanol, and a sonication time of 15 min are the optimal conditions for extraction of phenolics. FTIR analysis of methanolic extract confirmed the presence of phenolic functional groups. The compounds obtained from C. Dichotoma leaf extracts were identified by GCMS. UAE proves to be a promising technique for obtaining bioactive compounds with antioxidant potential from Cordia dichotoma leaves which can be potential applications in pharmaceutical, nutraceuticals, and functional food industries.

Optimizing the microwave-assisted hydrothermal extraction of pectin from tangerine by-product and its physicochemical, structural, and functional properties

Microwave-assisted hydrothermal extraction (MAHE) was optimized using a Box-Behnken design (BBD) of the response surface methodology (RSM) for optimal recovery of pectin from tangerine peel (TPP). The effects of three factors (pH, irradiation time and temperature) on extraction yield (EY), galacturonic acid content (GAC) and degree of esterification (DE) of pectin were investigated. The optimal extraction conditions were as follows: pH 1.7, irradiation time 12 min and temperature 109 °C. Under these conditions, the EY, GAC and DE were 30.4, 72.3 and 45.2%, respectively. The low methoxyl content of MHAE (45.2%) compared to CE is confirmed by the 1H NMR and FTIR spectra, and the emulsifying activity is 57.65% and 50.56% for CE and MHAE, respectively. The total phenolic content (TPC) of pectin produced using MAHE is 41.2 mg GAE/g, thus indicating higher antioxidant properties compared to pectin produced with CE, which had a TPC of 38.4 mg GAE/g. In addition, the X-ray diffraction (XRD) and surface morphological analysis (SEM) results showed that TPP had a rough surface and crystalline structure. Overall, our findings show that TTP from MAHE can be used as a natural antioxidant ingredient in the functional food and pharmaceutical industries.

Stabilization of delphinidin-3-O-rutinoside by mixed β-conglycinin and hydrolysates of glycinin upon heating

The selectively hydrolyzed soy protein composed of β-conglycinin (7S) and glycinin hydrolysates (GH) showed a superior protective effect on the delphinidin-3-O-rutinoside (D3R) during the steaming of colored wheat dough. To clarify the potential mechanism, 7S and GH were isolated and combined in varied ratios to mimic the RG proteins, and the interactions between proteins and D3R were studied by combined multispectral and molecular dynamics simulation study. The results suggested that 7S showed a higher stabilization effect of D3R than GH upon heating. In contrast, the optimum effect was noticed when incorporated with the mixed proteins with equal level of 7S and GH. D3R induced conformational changes of 7S and GH upon heating, and D3R formed complexes with proteins via hydrophobic interactions, and it was a static quenching process. The optimal binding affinity to D3R was observed with equal level of GH and 7S, contributing to enhanced thermal stability. Compared with GH, 7S could bind more amino acids and form a more stable complex with D3R. The results of this study could provide a theoretical basis for the preservation of D3R upon thermal processing and promote the application of mixed soy proteins in the functional food industry.

Effect of polyphenols from kiwi by-products (PKWP) on redox and metabolic homeostasis of HepG2 cells

Polyphenols from kiwi by-products (PKWP) have been previously reported to have an inhibitory effect on cancer cells; but, the potential anti-cancer mechanism remains unknown. Metabolic alterations in cancer cells provide bioenergy and substances for uncontrolled proliferation and development, and interfering with the metabolic pathways has been regarded as effective in impeding cancer progression. Cancer cells are also characterised by a relatively higher level of oxidative stress and an enhanced antioxidant defence system, facilitating multiple stages of tumorigenesis. Anti-cancer mechanisms of PKWP based on metabolic and redox homeostasis in HepG2 cells were thus investigated in the present work. The results showed that PKWP effectively decreased HepG2 cell viability in a concentration-dependent manner. PKWP caused metabolic disorders in HepG2 cells, and significantly affected the content of about 32 metabolites. PKWP mainly inhibited saccharide synthesis and glycolysis, and restricted the utilisation of amino acids. PKWP stimulated ROS production, and caused lipid peroxidation, resulting in oxidative damage. PKWP also down-regulated the activities of T-SOD and CAT, and the level of GSH, and inhibited the protein expressions of HO-1 and COX-2, weakening the cellular antioxidant capacity. Thus, PKWP could exert prominent anti-cancer activity in HepG2 cells by disrupting metabolic homeostasis, and induction of oxidative stress. These findings will provide evidence for further elucidation of the anti-cancer mechanism of PKWP, and the potential application of PKWP as a natural ingredient in functional food, cosmetic, and pharmaceutical industries.

Ocimum sanctum: The Journey from Sacred Herb to Functional Food.

In recent years, the growing demand for herbal-based formulations, including functional foods, has acquired significant attention. This study highlights historical, botanical, ecological, and phytochemical descriptions and different extraction mechanisms of Ocimum sanctum utilized in its processing. Besides this, it explores the utilization of Ocimum sanctum as a functional food ingredient in various food products such as bakery products (biscuits, bread), dairy products (herbal milk, cheese), and beverages (tea, juice, wine) while focusing on their evaluation parameters, preparation techniques, and pharmacological activities. In terms of other pharmacological properties, Ocimum sanctum-infused functional foods exhibited cognitiveenhancing properties, adaptogenic qualities, anti-obesity effects, gastroprotective, antiinflammatory, hypoglycemic, and immuno-modulatory effects. Thus, the diverse properties of Ocimum sanctum offer exciting opportunities for the development of functional foods that can promote specific health issues, so future research should focus on developing and analyzing novel Ocimum sanctum-based functional foods to meet the growing demand of the functional food industry.

Identification and quantification of flavonoids in edible dock based on UPLC-qTOF MS/MS and molecular networking

Edible dock, also known as Rumex patientia L.×Rumex tianschanicus A. LOS., exhibiting the characteristics of high yield, high protein and high nutrition, is widely used in the functional food industry and Chinese herbal medicine while short of secondary metabolites research. This study used UPLC-qTOF MS with two ion polarity in conjunction with Molecular Networking from Global Natural Products Social (GNPS) platform. Then, these 16 flavonoid substances including quercetin derivatives and kaempferol derivatives, firstly were identified from leaves in edible dock and were systematically investigated by UPLC-qTOF MS/MS. MS/MS experiments found that quercetin derivatives have five common characteristic ions, including m/z 300, m/z 271, m/z 255, m/z 243, and m/z 151. In addition, kaempferol derivatives have three common characteristic ions, including m/z 284, m/z 255, and m/z 227. Subsequently, 7 representative constituents were quantified via UPLC-QQQ MS with chemometrics, and the total content of 7 major flavonoids in its dry leaves is 6.988 mg/g in the 21st day samples. The work provided abundant metabolites information of flavonoids in edible dock, and the common characteristic ions will facilitate the building blocks-based molecular network (BBMN) to predict novel framework compounds from quercetin derivatives and kaempferol derivatives, laying the basis for exploitation of edible dock in the fields of pharmaceuticals, health food, and livestock feed.

Diversity of genome size, endopolyploidy and SCoT markers in 20 Trigonella (Fabaceae) species.

The Trigonella species possess medicinal, nutraceutical and pharmaceutical properties due to the presence of many bioactive compounds. Its therapeutic effects are mostly valuable in medicine, cosmetics and the functional food industry. Correct genetic characterisation of plant material is needed to increase the potential of Trigonella species by breeding and conservation programs. The aim of this study was to develop a reliable marker system to support the morphological and phytochemical analysis in Trigonella taxonomic research, species identification and characterization as well as determination of the interspecific variation within this genus along with relationships between species. For this purpose, flow cytometry and SCoT molecular markers were combined. Flow cytometric analyses revealed that Trigonella species possess very small and small genomes. The range of genome sizes was from 1.10 to 5.76 pg/2C, with most species possessing very small genomes (< 2.8 pg/2C). In seeds of 14 species endopolyploid nuclei were detected. Flow cytometric analysis of genome size enabled quick identification of four out of 20 species, while combined with endopolyploidy detection in seeds, facilitated distinction of the next seven species. ScoT molecular markers helped to identify closely related species with similar genome size and cell cycle activity. Therefore, flow cytometry was proposed as the first-choice method for quick accession screening, while the more detailed genetic classification was obtained using SCoT molecular markers.

Fermenting Buckwheat Seeds (Fagopyrum esculentum) with Aspergillus and subsequent amylase treatments enhance phenolic content and antioxidant activities

This research focused on investigating the effects of fermenting processed buckwheat with different Aspergillus species and subsequent treatment with α-amylase, β-amylase, and Glucoamylase. The study found that fermenting with Aspergillus Oryzae 82-3, followed by β-amylase treatment, significantly impacted saccharification within 2 hours, leading to increased total polyphenol content, rutin, and quercetin levels. High-Performance Liquid Chromatography (HPLC) results showed that Asp-82-3 with β-amylase had the highest rutin and quercetin levels. The saccharified buckwheat also exhibits elevated total protein and total carbohydrate content. DPPH analysis revealed enhanced antioxidant activity in treated samples. In vitro assays demonstrated that buckwheat saccharification with amylase after Aspergillus fermentation resulted in potent production, with Asp-82-3 and β-amylase showing the highest Nitric Oxide (NO) production. The study concludes that combining Aspergillus species and amylase for buckwheat saccharification enhances its antioxidant capacity and functional value, making it valuable in the functional food industry.

Structural characterization of Porphyra haitanensis extracts and their effects on structure, physicochemical properties, and in vitro digestibility of corn starch

Porphyra haitanensis with many bioactive components has great prospects for application in the functional food, pharmaceutical, and cosmeceutical industries. In this study, two sequentially extracted fractions (PhE1 & PhE2) were isolated and structurally characterized. The results showed that PhE1 was mainly composed of protein (36.82%) and neutral sugar (32.43%), while PhE2 mainly contained neutral sugar (58.70%). Both had galactose as main monosaccharides, PhE2 also contained a small amount of glucose. To widen the application of PhEs in starchy foods, they were added to corn starch (CS) system and co-gelatinized. Rheological tests indicated that PhEs could effectively affect gel strength of CS. The addition of PhEs effectively inhibited the content of leached amylose in CS gelatinization system except those at an addition of 5% PhE1 and 5% PhE2. FT-IR data suggested that PhE1 could improve the short-range order, but PhE2 showed no significant effects. SEM images showed that the pore wall of the composites thickened, and the network structure became relatively ordered. In vitro tests, PhEs significantly reduced the contents of rapidly digestible starch, and PhE1 presented better effects. Therefore, PhEs may be used as potential materials to delay the digestion of CS and related products.

Modulatory Effects of the Kuwanon-Rich Fraction from Mulberry Root Bark on the Renin-Angiotensin System.

In this study, we investigated the anti-hypertensive properties of mulberry products by modulating the renin-angiotensin system (RAS). Comparative analysis showed that the ethyl acetate fractions, particularly from the Cheongil and Daeshim cultivars, contained the highest levels of polyphenols and flavonoids, with concentrations reaching 110 mg gallic acid equivalent (GE)/g and 471 mg catechin equivalent (CE)/g of extract, respectively. The ethyl acetate fraction showed superior angiotensin-converting enzyme (ACE) inhibitory activity, mainly because of the presence of the prenylated flavonoids kuwanon G and H. UPLC/Q-TOF-MS analysis identified kuwanon G and H as the primary active components, which significantly contributed to the pharmacological efficacy of the extract. In vivo testing of mice fed a high-salt diet showed that the ethyl acetate fraction substantially reduced the heart weight and lowered the serum renin and angiotensinogen levels by 34% and 25%, respectively, highlighting its potential to modulate the RAS. These results suggested that the ethyl acetate fraction of mulberry root bark is a promising candidate for the development of natural ACE inhibitors. This finding has significant implications for the management of hypertension through RAS regulation and the promotion of cardiovascular health in the functional food industry.

Fractionation and identification of bioactive peptides from red macroalgae protein hydrolysates: In silico analysis and in vitro bioactivities

Recently, bioactive peptides derived from algae sources have gained significant recognition as vital functional ingredients in the development of health-enhancing foods and nutraceuticals. In this study, protein hydrolysates (SCPH and GSPH) derived from two red macroalgae (Sphaerococcus coronopifolius and Gelidium spinosum) were fractionated using semi-preparative-reversed phase high-performance liquid chromatography (RP-HPLC). Then, the peptides contained in the obtained fractions were identified by RP-HPLC coupled with tandem mass spectrometry (MS/MS). In silico analyzes of hydrophobicity, potential bioactivity using PeptideRanker, and toxicity of identified peptides were performed. Moreover, the prediction of Angiotensin-converting enzyme (ACE)- and Dipeptidyl-peptidase (DPP-IV)-inhibitory peptides using a quantitative structure-activity relationship (QSAR) was also carried out. Furthermore, in vitro evaluation of antioxidant and antibacterial activities, as well as ACE-, and DPP-IV-inhibitory properties was conducted for all peptide fractions. Our results showed that SCPH and GSPH fractions contain a large percentage of highly hydrophobic peptides with low molecular weight, and they exhibit no toxic effect. Among all identified peptides, 61 and 39 peptides, respectively from SCPH and GSPH fractions, presented a PeptideRanker score superior to 0.8. These peptide sequences exhibited a high proportion of potent predicted ACE- and DPP-IV-inhibitory peptides. Additionally, most of the peptide fractions exerted antioxidant, antibacterial, anti-ACE, and anti-DPP-IV inhibitory activities at different levels. Among them, F2 to F6 were the most active fractions. Overall, the results suggest that the bioactive peptide fractions separated from two red macroalgae protein hydrolysates could be considered as a beneficial ingredient for nutraceutical and functional food industries.

Impact of water combined wet ball milling extraction and functional evaluation of dietary fiber from papaya (Carica papaya L)

This study evaluates the structural, physicochemical, functional and rheological properties of papaya dietary fibers (DFs) extracted by alkaline, water and combination of water/wet ball milling. The particle size of DF subjected to water/wet ball milling (WB-DF) was considerably reduced compared to DF extracted by water (W-DF) or alkaline (AL-DF) methods. WB-DF in comparison AL-DF increased the water holding capacity (WHC) by 4.1 folds, oil holding capacity (OHC) by 1.7 folds and water swelling capacity (WSC) by 2.6 folds. WB-DF also improved the cholesterol adsorption capacity (CAC), glucose adsorption (GAC), nitrite-ion adsorption capacity (NIAC) and antioxidant activity. The FT-IR spectra displayed changes in peak intensities observed in the three modified DFs. In addition, WB-DF showed highest viscosity among all smaples. The distributions of monosaccharides in the DFs were affected by the different extractions. Consequently, DFs extracted through the water/wet ball milling exhibit significant potential for applications in the functional food industry.

Mapping The Worldwide Knowledge of Jack Bean by A Bibliometric Approach

Indonesia's indigenous inhabitants acknowledge the local legume plant known as jack bean. The Jack bean has various advantages, including increased production, a shorter lifespan, upright stems mimicking shrubs, and improved tolerance to biotic and abiotic stresses. Nonetheless, the jack bean plant is particularly vulnerable due to harmful compounds such as canavaline, choline, hydroziamine acid, trogonelin, and cyanide. A bibliometric study was performed to locate studies on jack beans. The data collection procedure includes executing an extensive search in Scopus-indexed journals using the keywords "Jack Bean." It could limit the search to the article abstract, title, keywords, and country. The articles included in this study were published between 2000 and 2023. The search yielded a total of 999 items. The data was obtained on September 10, 2023; any later alterations are not considered in this research. According to the published literature, over the last 23 years, many studies have been conducted to develop urease inhibition and antioxidants from jack beans. However, little research has been done into the functional benefits of jack bean bioactive components for enhancing bodily health, such as antidiabetic, antihypertensive, and anticancer properties. This article contributes to helping researchers fill jack bean-related research gaps and apply technology to the industrialization process of jack beans in the functional food and nutraceutical industries.

Platycodon grandiflorum saponins: Ionic liquid-ultrasound-assisted extraction, antioxidant, whitening, and antiaging activity

This study explored the use of ionic liquid-ultrasound (ILU)-assisted extraction to enhance the extraction rate of Platycodon grandiflorum saponins (PGSs), and the content, extraction mechanism, antioxidant activity, whitening, and antiaging activity of PGSs prepared using ILU, ultrasound-water, thermal reflux-ethanol, and cellulase hydrolysis were compared. The ILU method particularly disrupted the cell wall, improved PGS extraction efficiency, and yielded a high total saponin content of 1.45 ± 0.02 mg/g. Five monomeric saponins were identified, with platycodin D being the most abundant at 1.357 mg/g. PGSs displayed excellent in vitro antioxidant activity and exhibited inhibitory effects on tyrosinase, elastase, and hyaluronidase. The results suggest that PGSs may have broad antioxidant, skin-whitening, and antiaging potential to a large extent. Overall, this study provided valuable insights into the extraction, identification, and bioactivities of PGSs, which could serve as a reference for future development and application of these compounds in the functional foods industry.

Pectin-based emulsion gels prepared by acidic and ionotropic methods for intestinal targeted delivery in vitro

Considering the different potential roles of the small intestine and colon in the functions of bioactive components, this study was performed to design a pectin-based controlled delivery system targeting different intestinal sections according to emulsification gelation methods (i.e., pectin gelated with acidified ethanol, iron, and calcium: PE-H, PE-Fe, and PE-Ca, respectively). The properties and targeted delivery of pectin-based emulsion gels were compared. All emulsion gels exhibited similar diameter and acceptable roundness with naringin encapsulation efficiency of approximately 90%. Cross-sections of PE-H, PE-Fe, and PE-Ca exhibited loose networks, large voids, and dense structures, resulting in diverse time dependence during digestion. Furthermore, PE-Ca showed the fastest completion of gelation and exhibited excellent hardness properties, suggesting that it would have the strongest anti-digestive effect. PE-Fe showed time- and pH-dependent swelling behavior in simulated intestinal fluid. Simulated digestion experiments indicated burst release and slow release of naringin from PE-H and PE-Fe, respectively, due to their differences in pH responsiveness and time dependence; a similar amount of naringin was released from PE-Ca after enzyme-triggered digestion in simulated colon fluid. Overall, distinct emulsion gels achieved targeted disintegration in intestinal sites. PE-H and PE-Fe would contribute to the rapid and sustained release of naringin in the small intestine, respectively, whereas PE-Ca would contribute to naringin release in the colon. These findings provide new insights for the future design of specific delivery systems that can be used in the functional food industry; they indicate the robust potential for including pectin in emulsion-based foods with targeted functions.

Comparative Evaluation of Secondary Metabolite Chemodiversity of Citrus Genebank Collection in Greece: Can the Peel be More than Waste?

Citrus fruits are among the most economically important crops in the world. In the global market, the Citrus peel is often considered a byproduct but substitutes an important phenotypic characteristic of the fruit and a valuable source of essential oils, flavonoids, carotenoids, and phenolic acids with variable concentrations. The Mediterranean basin is a particularly dense area of autochthonous genotypes of Citrus that are known for being a source of healthy foods, which can be repertoires of valuable genes for molecular breeding with the focus on plant resistance and quality improvement. The scope of this study was to characterize and compare the main phenotypic parameters (i.e., peel thickness, fruit volume, and area) and levels of bioactive compounds in the peel of fruits from the local germplasm of Citrus in Greece, to assess their chemodiversity regarding their polyphenolic, volatile, and carotenoid profiles. A targeted liquid chromatographic approach revealed hesperidin, tangeretin, narirutin, eriocitrin, and quercetin glycosides as the major polyphenolic compounds identified in orange, lemon, and mandarin peels. The content of tangeretin and narirutin followed the tendency mandarin > orange > lemon. Eriocitrin was a predominant metabolite of lemon peel, following its identification in lower amounts in mandarin and at least in the orange peel. For these citrus-specific metabolites, high intra- but also interspecies chemodiversity was monitored. Significant diversity was found in the essential oil content, which varied between 1.2 and 3% in orange, 0.2 and 1.4% in mandarin, and 0.9 and 1.9% in lemon peel. Limonene was the predominant compound in all Citrus species peel essential oils, ranging between 88 and 93% among the orange, 64 and 93% in mandarin, and 55 and 63% in lemon cultivars. Carotenoid analysis revealed different compositions among the Citrus species and accessions studied, with β-cryptoxanthin being the most predominant metabolite. This large-scale metabolic investigation will enhance the knowledge of Citrus peel secondary metabolite chemodiversity supported by the ample availability of Citrus genetic resources to further expand their exploitation in future breeding programs and potential applications in the global functional food and pharmaceutical industries.

Preparation and characterization of zein-caseinate-pectin complex nanoparticles for encapsulation of curcumin: pectin extracted by high-speed shearing from passion fruit (Passiflora edulis f. flavicarpa) peel.

Pectin extracted by high-speed shearing from passion fruit peel (HSSP) is a potentially excellent wall material for encapsulating curcumin, which has multiple advantages over pectin prepared by heated water extraction. HSSP was used to fabricate complex nanoparticles of zein-sodium caseinate-pectin for encapsulation of curcumin in this study. The influence of heating on the physicochemical properties of the composite nanoparticles was also investigated, as well as the effect of composite nanoparticles on the encapsulation efficiency, antioxidant activity and release characteristics of curcumin. The nanoparticles were formed through electrostatic interactions, hydrogen bonds and hydrophobic interactions between the proteins and HSSP. A temperature of 50 °C was more favorable for generating compact and small-sized nanoparticles, which could effectively improve the encapsulation efficiency and functional properties. Moreover, compared to other pectin used in the study, the nanoparticles prepared with HSSP showed the best functionality with a particle size of 234.28 ± 0.85 nm, encapsulation rate of 90.22 ± 0.54%, free radical scavenging rate of 78.97% and strongest protective capacity in simulated gastric fluid and intestinal release effect. Zein-sodium caseinate-HSSP is effective for encapsulating and delivering hydrophobic bioactive substances such as curcumin, which has potential applications in the functional food and pharmaceutical industries. © 2024 Society of Chemical Industry.

Physicochemical Properties and Biological Activities of Quinoa Polysaccharides.

Quinoa, known as the "golden grain" for its high nutritional value, has polysaccharides as one of its sources of important nutrients. However, the biological functions of quinoa polysaccharides remain understudied. In this study, two crude polysaccharide extracts of quinoa (Q-40 and Q-60) were obtained through sequential precipitation with 40% and 60% ethanol, with purities of 58.29% (HPLC) and 62.15% (HPLC) and a protein content of 8.27% and 9.60%, respectively. Monosaccharide analysis revealed that Q-40 contained glucose (Glc), galacturonic acid (GalA), and arabinose (Ara) in a molar ratio of 0.967:0.027:0.006. Q-60 was composed of xylose (xyl), arabinose (Ara), galactose, and galacturonic acid (GalA) with a molar ratio of 0.889:0.036:0.034:0.020. The average molecular weight of Q-40 ranged from 47,484 to 626,488 Da, while Q-60 showed a range of 10,025 to 47,990 Da. Rheological experiments showed that Q-40 exhibited higher viscosity, while Q-60 demonstrated more elastic properties. Remarkably, Q-60 showed potent antioxidant abilities, with scavenging rates of 98.49% for DPPH and 57.5% for ABTS. Antibacterial experiments using the microdilution method revealed that Q-40 inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), while Q-60 specifically inhibited MRSA. At lower concentrations, both polysaccharides inhibited MDA (MD Anderson Cancer Center) cell proliferation, but at higher concentrations, they promoted proliferation. Similar proliferation-promoting effects were observed in HepG2 cells. The research provides important information in the application of quinoa in the food and functional food industries.

Immunostimulatory Effect of Ovomucin Hydrolysates by Pancreatin in RAW 264.7 Macrophages via Mitogen-Activated Protein Kinase (MAPK) Signaling Pathway.

Ovomucin (OM), which has insoluble fractions is a viscous glycoprotein, found in egg albumin. Enzymatic hydrolysates of OM have water solubility and bioactive properties. This study investigated that the immunostimulatory effects of OM hydrolysates (OMHs) obtained by using various proteolytic enzymes (Alcalase®, bromelain, α-chymotrypsin, Neutrase®, pancreatin, papain, Protamax®, and trypsin) in RAW 264.7 cells. The results showed that OMH prepared with pancreatin (OMPA) produced the highest levels of nitrite oxide in RAW 264.7 cells, through upregulation of inducible nitric oxide synthase mRNA expression. The production of pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-6 were increased with the cytokines mRNA expression. The effect of OMPA on mitogen-activated protein kinase signaling pathway was increased the phosphorylation of p38, c-Jun NH2-terminal kinase, and extracellular signal-regulated kinase in a concentration-dependent manner. Therefore, OMPA could be used as a potential immune-stimulating agent in the functional food industry.

Characterisation of functional pea protein hydrolysates and their immunomodulatory activity

SummaryPea proteins has been widely used in food industry due to its functionality and health benefits. Pea peptides derived from pea proteins are considered as promising source of novel functional food. However, the chemical structure of pea peptides with immunomodulatory activity remains unclear. In this work, 46 pea peptides with molecular weight from 533.28 to 1462.78 were identified from pea protein hydrolysates. The hydrolysates could significantly increase the immunomodulatory activity of the macrophages by elevation of phagocytic activity, promoting the production of nitric oxide and pro‐inflammatory cytokines (TNF‐α and IL‐6) at the doses of 0.25–1.0 mg mL−1. Moreover, upregulation of iNOS, TNF‐α and IL‐6 were related to the activity of pea protein hydrolysates. Fourteen peptides with activity scores &gt; 0.3 showed good affinity with TLR4/MD‐2 by molecular docking. TLR4 activation was involved in the immunomodulatory activity of bioactive pea peptides through a hydrogen bond, Pi‐cation, Pi‐Sigma, Pi‐Pi stacked and/or Pi‐Pi T‐shaped interactions respectively. The above results indicated that pea peptides could be used as healthy food with immunomodulatory function, promoting the development of pea proteins in the functional food industry.