Enhanced stability of berry pomace polyphenols delivered in protein-polyphenol aggregate particles to an in vitro gastrointestinal digestion model

Utilization of egg white powders to mitigate the astringency of Aronia berry juice and produce protein-Proanthocyanidin aggregates with enhanced stability during digestion

Aronia berry has a strong unpleasant astringency, however, few approaches have been developed to modify it. This study aims to screen out the suitable proteins to mitigate astringency in aronia juice, elucidate the interaction mechanism, and evaluate the digestive stability of formed complexes. Among proteins tested, two egg white powders (original P-110 and modified M-200) were the optimal ones with 0.5 % (w/w) addition to effectively reduce astringency. At room temperature (25 °C), the interaction of proanthocyanidins (PAs) with both P-110 and M-200 was spontaneous, endothermic, and majorly driven by hydrophobic interaction. The binding affinity of PAs with M-200 is stronger than that with P-110. On the other hand, the egg white protein-PA aggregates enhanced the stability of PAs during digestion, allowing more PAs to reach gut microbiota to exert their bioactivities. This study improves fundamental understanding of egg white protein-PAs interaction and provides a practical processing approach for aronia industry.

Recent advances in the plant protein-polyphenol interactions for the stabilization of emulsions

Proteins from plant sources including legumes, cereals and oilseeds are gaining attention due to their suitability for sustainable production, functionality, and positive consumer perception. On the other hand, polyphenols (PPs) are receiving considerable attention as natural ingredients in the human diet due to their potent antioxidant and anti-inflammatory properties. Recent studies indicate that the emulsifying properties of plant proteins (PLPs) can be improved after modification through covalent and/or non-covalent interactions with PPs due to the changes in the conformation and/or the surface chemistry of the proteins. Complexes formed between PLPs-PPs can serve as innovative ingredients for developing novel food products with modified textural properties. Also, Pickering emulsions, multiple emulsions, multilayer emulsions, nanoemulsions, and high internal phase emulsions can be stabilized by such systems to deliver bioactive compounds. This paper reviews the most recent research on the PLP-PP interactions and their role in the stabilization of various emulsion-based systems. A special emphasis is given to modifying the structure and functionality of PLPs and PPs. The challenges and opportunities of applying PLP-PP interactions in emulsion-based systems are also highlighted.

Modification of Inca peanut albumin-polyphenol conjugates by chitosan through laccase catalysis: Structural, interfacial, and functional properties

As a green method, enzyme crosslinking can catalyze chitosan (CS) to improve further the structural, interfacial, and functional properties of Inca peanut albumin (IPA)-polyphenols. However, the structural impact of laccase-catalyzed CS on different IPA-polyphenol conjugates has not been reported. Results revealed that enzymatic cross-linking of IPA-gallic acid (GA) and IPA- (-)-epigallocatechin-3-gallate (EGCG) with CS resulted in a decrease in α-helices, an increase in β-helices, and a more ordered structure. The contact angles of IPA-GA-CS and IPA-EGCG-CS decreased from 99.4° and 101.2° to 89.9° and 95.4°, respectively, indicating reduced hydrophobicity and enhanced interfacial adsorption. Furthermore, using copolymers as emulsifiers significantly improved the emulsification and antioxidant properties of high internal phase Pickering emulsions (HIPEs). In particular, the apparent viscosity and viscoelasticity of HIPEs constructed with IPA-GA-CS notably improved, and the EGCG-induced copolymers exhibited superior lipid antioxidation. The method of laccase-mediated crosslinking for the preparation of protein-polyphenol-polysaccharide polymers enhances the functional properties and anti-pH sensitivity of IPA, representing a novel protein modification strategy.

Exploring the Potential of Anthocyanins for Repairing Photoaged Skin: A Comprehensive Review

Long-term exposure to ultraviolet (UV) rays can result in skin photoaging, which is primarily characterized by dryness, roughness, pigmentation, and a loss of elasticity. However, the clinical drugs commonly employed to treat photoaged skin often induce adverse effects on the skin. Anthocyanins (ACNs) are water-soluble pigments occurring abundantly in various flowers, fruits, vegetables, and grains and exhibiting a range of biological activities. Studies have demonstrated that ACNs contribute to the repair of photoaged skin due to their diverse biological characteristics and minimal side effects. Evidence suggests that the stability of ACNs can be enhanced through encapsulation or combination with other substances to improve their bioavailability and permeability, ultimately augmenting their efficacy in repairing photoaged skin. A growing body of research utilizing cell lines, animal models, and clinical studies has produced compelling data demonstrating that ACNs mitigate skin photoaging by reducing oxidative stress, alleviating the inflammatory response, improving collagen synthesis, alleviating DNA damage, and inhibiting pigmentation. This review introduces sources of ACNs while systematically summarizing their application forms as well as mechanisms for repairing photoaged skin. Additionally, it explores the potential role of ACNs in developing functional foods. These findings may provide valuable insight into using ACNs as promising candidates for developing functional products aimed at repairing photoaged skin.

A critical appraisal of geroprotective activities of flavonoids in terms of their bio-accessibility and polypharmacology

Flavonoids, a commonly consumed natural product, elicit health-benefits such as antioxidant, anti-inflammatory, antiviral, anti-allergic, hepatoprotective, anti-carcinogenic and neuroprotective activities. Several studies have reported the beneficial role of flavonoids in improving memory, learning, and cognition in clinical settings. Their mechanism of action is mediated through the modulation of multiple signalling cascades. This polypharmacology makes them an attractive natural scaffold for designing and developing new effective therapeutics for complex neurological disorders like Alzheimer's disease and Parkinson's disease. Flavonoids are shown to inhibit crucial targets related to neurodegenerative disorders (NDDs), including acetylcholinesterase, butyrylcholinesterase, β-secretase, γ-secretase, α-synuclein, Aβ protein aggregation and neurofibrillary tangles formation. Conserved neuro-signalling pathways related to neurotransmitter biogenesis and inactivation, ease of genetic manipulation and tractability, cost-effectiveness, and their short lifespan make Caenorhabditis elegans one of the most frequently used models in neuroscience research and high-throughput drug screening for neurodegenerative disorders. Here, we critically appraise the neuroprotective activities of different flavonoids based on clinical trials and epidemiological data. This review provides critical insights into the absorption, metabolism, and tissue distribution of various classes of flavonoids, as well as detailed mechanisms of the observed neuroprotective activities at the molecular level, to rationalize the clinical data. We further extend the review to critically evaluate the scope of flavonoids in the disease management of neurodegenerative disorders and review the suitability of C. elegans as a model organism to study the neuroprotective efficacy of flavonoids and natural products.

Effects of preheat treatment and syringic acid binding on the physicochemical, antioxidant, and antibacterial properties of black soybean protein isolate before and after in vitro digestion

This study investigated the effects of preheat treatment (70-100 °C) and syringic acid (SA) grafting on the antioxidant, antibacterial, and physicochemical properties of black soybean protein isolate (BSPI) before and after in vitro digestion. The results revealed that both preheat treatment and SA grafting increased the digestibility and the absolute zeta potential value of BSPI. However, as the preheating temperature increased, the antioxidant ability of BSPI decreased, which was improved by SA grafting. During in vitro digestion, the absolute zeta potential and antioxidant activities of preheated BSPI and preheated BSPI-SA complex followed the order: intestine > gastric > before digestion. Compared with before digestion, preheated BSPI with its SA complex after in vitro digestion exhibited excellent antibacterial activities. Importantly, the preheated BSPI-SA complex enhanced the SA recovery rate during digestion and SA stability, with the highest recovery rate observed for the SA-grafted BSPI with preheat treatment at 100°C (BSPI100-SA). The principal component analysis sufficiently distinguished preheated BSPI and preheated BSPI-SA complexes. There were partitions between BSPI and BSPI-SA treated at different preheating temperatures. This study contributes to expanding the potential applications of BSPI with its SA complex in food products and offers guidance for designing SA delivery systems. PRACTICAL APPLICATION: Preheated BSPI-SA complexes could serve as functional ingredients in food or health products. Besides, preheated BSPI has application potential as a carrier for SA delivery.

Recent advances in dietary polyphenols (DPs): antioxidant activities, nutrient interactions, delivery systems, and potential applications

Dietary polyphenols (DPs) have garnered growing interest because of their potent functional properties and health benefits. Nevertheless, the antioxidant capabilities of these substances are compromised by their multifarious structural compositions. Furthermore, most DPs are hydrophobic and unstable when subjected to light, heat, and varying pH conditions, restricting their practical application. Delivery systems based on the interactions of DPs with food constituents such as proteins, polypeptides, polysaccharides, and metal ions are being created as a viable option to improve the functional activities and bioavailability of DPs. In this review, the latest discoveries on the dietary sources, structure-antioxidant activity relationships, and interactions with nutrients of DPs are discussed. It also innovatively highlights the application progress of polyphenols and their green nutraceutical delivery systems. The conclusion drawn is that the various action sites and structures of DPs are beneficial for predicting and designing polyphenols with enhanced antioxidant attributes. The metal complexation of polyphenols and green encapsulation systems display promising outcomes for stabilizing DPs during food processing and in vivo digestion. In the future, more novel targeted delivery systems of DPs for nutrient fortification and intervention should be developed. To expand their usage in customized food products, they should meet the requirements of specific populations for personalized food and nutrition.

A comprehensive review on the recent trends in extractions, pretreatments and modifications of plant-based proteins

Plant-based proteins offer sustainable and nutritious alternatives to animal proteins with their techno-functional attributes influencing product quality and designer food development. Due to the inherent complexities of plant proteins, proper extraction and modifications are vital for their effective utilization. This review highlights the emerging sources of plant-based proteins, and the recent statistics of the techniques employed for pretreatment, extraction, and modifications. The pretreatment, extraction and modification approach to modify plant proteins have been classified, addressed, and the recent applications of such methodologies are duly indicated. Furthermore, this study furnishes novel perspectives regarding the potential impacts of emerging technologies on the intricate dynamics of plant proteins. A thorough review of 100 articles (2018-2024) shows the researchers' keen interest in investigating novel plant proteins and how they can be used; seeds being the main source for protein extraction, followed by legumes. Use of by-products as a protein source is increasing rapidly, which is noteworthy. Protein studies still lack knowledge on protein fraction, antinutrients, and pretreatments. The use of physical methods and their combination with other techniques are increasing for effective and environmentally friendly extraction and modification of plant proteins. Several studies explore the effect of protein changes on their function and nutrition, especially with a goal of replacing ingredients with plant proteins that have improved or enhanced qualities. However, the next step is to investigate the sophisticated modification methods for deeper insights into food safety and toxicity.

Macronutrient digestion and polyphenol bioaccessibility in oat milk tea products: an in vitro gastrointestinal tract study

People are increasingly preparing milk tea using plant-based milks rather than cow's milk, e.g., vegans, those with lactose intolerance, and those with flavor preferences. However, adding plant-based milks to tea may impact the digestion, release, and bioaccessibility of nutrients and nutraceuticals in both the tea and milk. In this study, oat milk tea model systems (OMTMSs) containing different fat and tea polyphenol concentrations were used to explore the impact of tea on macronutrient digestion in oat milk, as well as the impact of oat milk matrix on the polyphenol bioaccessibility in the tea. An in vitro gastrointestinal model that mimics the mouth, stomach, and small intestine was used. Tea polyphenols (>0.25%) significantly reduced the glucose and free fatty acids released from oat milk after intestinal digestion. Tea polyphenols (>0.10%) also inhibited protein digestion in oat milk during gastric digestion but not during intestinal digestion. The bioaccessibility of the polyphenols in the tea depended on the fat content of oat milk, being higher for medium-fat (3.0%) and high-fat (5.8%) oat milk than low-fat (1.5%) oat milk. Liquid chromatography-tandem mass spectrometry (UPLC-ESI-MS/MS) analysis showed that lipids improved the tea polyphenol bioaccessibility by influencing the release of flavonoids and phenolic acids from the food matrices. These results provide important information about the impact of tea on the gastrointestinal fate of oat milk, and vice versa, which may be important for enhancing the healthiness of plant-based beverages.

Dietary Sources, Stabilization, Health Benefits, and Industrial Application of Anthocyanins-A Review

Natural phytochemicals are well known to protect against numerous metabolic disorders. Anthocyanins are vacuolar pigments belonging to the parent class of flavonoids. They are well known for their potent antioxidant and gut microbiome-modulating properties, primarily responsible for minimizing the risk of cardiovascular diseases, diabetes, obesity, neurodegenerative diseases, cancer, and several other diseases associated with metabolic syndromes. Berries are the primary source of anthocyanin in the diet. The color and stability of anthocyanins are substantially influenced by external environmental conditions, constraining their applications in foods. Furthermore, the significantly low bioavailability of anthocyanins greatly diminishes the extent of the actual health benefits linked to these bioactive compounds. Multiple strategies have been successfully developed and utilized to enhance the stability and bioavailability of anthocyanins. This review provides a comprehensive view of the recent advancements in chemistry, biosynthesis, dietary sources, stabilization, bioavailability, industrial applications, and health benefits of anthocyanins. Finally, we summarize the prospects and challenges of applications of anthocyanin in foods.

Recent progress in promoting the bioavailability of polyphenols in plant-based foods

Polyphenols are important constituents of plant-based foods, exhibiting a range of beneficial effects. However, many phenolic compounds have low bioavailability because of their low water solubility, chemical instability, food matrix effects, and interactions with other nutrients. This article reviews various methods of improving the bioavailability of polyphenols in plant-based foods, including fermentation, natural deep eutectic solvents, encapsulation technologies, co-crystallization and amorphous solid dispersion systems, and exosome complexes. Several innovative technologies have recently been deployed to improve the bioavailability of phenolic compounds. These technologies may be utilized to increase the healthiness of plant-based foods. Further research is required to better understand the mechanisms of action of these novel approaches and their potential to be used in food production.

Stability of a novel glycosylated peanut protein isolate delivery system loaded with gallic acid

To overcome the shortcomings of gallic acid (GA) application, a novel glycosylated PPI delivery system was prepared for the first time in this study using the interaction between peanut protein isolate (PPI) and GA. The effects of glycosylation on the structural and functional properties of PPI and the functional properties of nanoparticles were investigated. The optimal nanoparticles were prepared at a mass ratio 1:3 of glycosylated PPI to GA with a particle size of 338.351 ± 18.823 nm and a PDI of 0.222 ± 0.039. Hydrophobic interactions were the main force maintaining the nanoparticle structure. The nanoparticles remained stable when exposed to different environmental factors. In addition, the DPPH and ABTS radical scavenging activities of nanoparticle-embedded GA were 35.94 ± 3.24 % and 62.59 ± 5.07 % after 108 h, which were significantly higher than those of the free GA group (P < 0.05). This study is important for developing GA and hydrophilic polyphenol delivery systems.

Non-covalent interaction between hemp seed globulin and two hemp seed phenolic compounds: Mechanism and effects on protein structure, bioactivity, and in vitro simulated digestion

This study focused on elucidating the non-covalent interactions between hemp seed globulin (GLB) and two hemp seed phenolic compounds, Cannabisin A (CA) and Cannabisin B (CB), and to explore these interactions on the protein's structure, conformation, and functionality. Fluorescence quenching and thermodynamic analysis revealed that static quenching governed non-covalent interaction processes, with hydrogen bonds and van der Waals forces functioning as major forces. This was further substantiated by molecular docking studies. The binding affinity order was CA > CB, indicating that the specific phenolic compound had a notable impact on the binding affinity. Furthermore, when complexed with CA, Tyr and Trp residues were exposed to a more hydrophilic environment than when complexed with CB. It was noted that the complexation with either CA or CB consistently affects GLB's secondary structure, particle size, and ζ-potential. GLB treated with the phenolic compounds exhibited enhanced ABTS and DPPH scavenging activities and improved digestibility compared to untreated GLB. Furthermore, the non-covalent interactions significantly increased CA's water solubility, highlighting GLB as a promising natural carrier for hydrophobic bioactive components. These findings hold potential implications for enhancing hemp seed protein applications within the food industry by positively influencing its functional properties and bioactivity.

Fabrication mechanism and functional properties of ovalbumin fibrils prepared by acidic heat treatment

BACKGROUND

Ovalbumin (OVA), accounting for 50% of proteins in egg white, is a kind of high-quality protein with excellent nutritional and processing functions. Acid heat treatment will induce the deformation and filtration of OVA, endowing it with improved functionality. However, the molecular kinetic process during the fibrillation of OVA and the application of the fabricated OVA fibrils (OVAFs) have not been thoroughly studied and revealed.

RESULTS

In this study, the fabrication mechanism and the application OVAFs as an interfacial stabilizer and polyphenol protector were investigated. Acidic (pH 3.0) heat treatment was used to induce the fibrillation of OVA, and thioflavin T fluorescence intensity, molecular weight distribution, and the tertiary and secondary structures of OVAF samples were recorded to determine the fibrillation efficiency and the molecular mechanism. The results showed that, in the initial stage of fibrillation, OVA first hydrolyzed to oligopeptides, accompanied by the exposure of hydrophobic domains. Then, oligopeptides were connected by disulfide bonds to form primary fibril monomers. Hydrophobic interaction and hydrogen bonding may participate in the further polymerization of the fibrils. The fabricated OVAFs were characterized by a β-sheet-rich structure and possessed improved emulsifying, foaming, and polyphenol protection ability.

CONCLUSION

The research work was meaningful for exploring the application of globular water-soluble OVA in an emerging nutritious food with novel texture and sensory properties. © 2023 Society of Chemical Industry.

Plant-Based Protein-Phenolic Interactions: Effect on different matrices and in vitro gastrointestinal digestion

This review summarizes the literature on the interaction between plant-based proteins and phenolics. The structure of the phenolic compound, the plant source of proteins, matrix properties (pH, temperature), and interaction mechanism (covalent and non-covalent) change the secondary structure, ζ-potential, surface hydrophobicity, and thermal stability of proteins as well as their functional properties including solubility, foaming, and emulsifying properties. Studies indicated that the foaming and emulsifying properties may be affected either positively or negatively according to the type and concentration of the phenolic compound. Protein digestibility, on the other hand, differs depending on (1) the phenolic concentration, (2) whether the food matrix is ​​solid or liquid, and (3) the state of the food-whether it is heat-treated or prepared as a mixture without heat treatment in the presence of phenolics. This review comprehensively covers the effects of protein-phenolic interactions on the structure and properties of proteins, including functional properties and digestibility both in model systems and real food matrix.

Interactions of legume phenols-rice protein concentrate towards improving vegan food quality: Development of a protein-phenols enriched fruit smoothie

Phenol-protein interaction is considered an effective tool to improve the functional properties of vegan proteins. The present work aimed to evaluate the covalent interaction between kidney bean polyphenols with rice protein concentrate and studied their characteristics for quality improvement in vegan-based foods. The impact of interaction on the techno-functional properties of protein was evaluated and the nutritional composition revealed that kidney bean was rich in carbohydrates. Furthermore, a noticeable antioxidant activity (58.11 ± 1.075 %) due to the presence of phenols (5.5 mg GAE/g) was observed for the kidney bean extract. Moreover, caffeic acid and p-Coumaric acid were confirmed using ultra-pressure liquid chromatography and the amount was 194.43 and 0.9272 mg/kg, respectively. A range of rice protein- phenols complexes (PPC0.025, PPC0.050, PPC0.075, PPC0.1, PPC0.2, PPC 0.5, PPC1) were examined and PPC0.2 and PPC0.5 showed significantly (p < 0.05) higher binding efficiency with proteins via covalent interaction. The conjugation reveals changes in physicochemical properties of rice protein, including, reduced size (178.4 nm) and imparted negative charges (-19.5 mV) of the native protein. The presence of amide Ⅰ, Ⅱ, Ⅲ, was confirmed in native protein and protein-phenol complex with vibration bands, particularly at 3784.92, 1631.07, and 1234 cm^-1, respectively. The X-ray diffraction pattern depicted a slight decrease in crystallinity after the complexation and scanning electron microscopy revealed the alteration in morphology from less to improved smoothness and continuous surface characteristics for the complex. Thermo gravimetric analysis revealed high thermal stability of the complex with a maximum weight loss at a temperature range of 400-500 °C. Protein-phenol complex added fruit-based smoothie was developed and it was found to be acceptable in terms of various sensory attributes including color & appearance, textural consistency, and mouthfeel as compared to the control smoothie. Overall, this study provided novel insights to understand the phenol-protein interactions and the possible use of the phenol-rice protein complex in the development of vegan-based food products.

In Vitro Hypoglycemic Potential, Antioxidant and Prebiotic Activity after Simulated Digestion of Combined Blueberry Pomace and Chia Seed Extracts

This study aimed to evaluate the hypoglycemic potential, antioxidant activity and prebiotic activity of a hydroalcoholic extract of blueberry pomace (BP), an aqueous extract of chia seeds (CS) and a novel combination of BP–CS extracts (BCM) for further use as ingredient of functional food. Spectrometric and HPLC analyses were used to characterize the total phenolic and flavonoid content and composition of BP, while CS was analyzed for total carbohydrate content. Data showed that the BCM mixture exerted an inhibition of α-amylase activity, which was 1.36 times higher than that of BP and 1.25 higher than CS extract. The mixture also showed better scavenging activity of free DPPH radicals than individual extracts, and had an IC50 value of 603.12 µg/mL. In vitro testing indicated that both serum- and colon-reaching products of simulated intestinal digestion of BCM presented the capacity to protect Caco-2 intestinal cells against oxidative stress by inhibition of reactive oxygen species production. In addition, the colon-reaching product of BCM digestion had the capacity to significantly (p < 0.05) stimulate the growth of Lactobacillus rhamnosus and Lactobacillus acidophilus, revealing a prebiotic potential. All these results indicated that improved biological activity of the novel combination of BP and CS extracts could be due to the synergistic action of constituents. The combination is recommended for further testing and the development of novel functional food for controlling type 2 diabetes and gastrointestinal conditions.

Assessment of the Bioaccessibility of Elaeagnus angustifolia L. Flour and Its Use in Cracker Formulation

In this study, in vitro digestion of polyphenols of oleaster (Elaeagnus angustifolia L.) flour (OF) and the potential use of OF in cracker production were studied. The results showed that 21.90 mg gallic acid equivalent (GAE)/g dry matter (DM) of total polyphenol (TP), 28.15 mg rutin equivalent (RE)/g DM of total flavonoid (TF) and 7709.13 mmol ascorbic acid equivalent (AAE)/100 g DM of antioxidant capacity (AC) were found in OF. The bioaccessibility and content of the OF polyphenols and their AC during in vitro digestion varied depending on the digestion stage. The stability of the OF polyphenols was higher in gastric stage (41.92%) than intestinal one (34.01%). OF was used to replace flour in the cracker formulation at the levels of 5, 10 and 15% (w/w) and increased the TP contents and AC of the crackers compared to the sample without OF (control). The addition of OF to the cracker dough increased the bioaccessibility of the cracker polyphenols. After digestion, bioaccessibilities of enriched crackers (107.90-126.81%) were found higher than that of control sample (93.73%). However, as the level of OF in cracker increased, bioaccessibility of polyphenols decreased. The results generally indicated that oleaster has a good potential for the enrichment of foods.

Protein-binding approaches for improving bioaccessibility and bioavailability of anthocyanins

Color is an important characteristic of food. Over the last 15 years, more attention has been paid to natural colorants because of the rising demand for clean-label food products. Anthocyanins, which are a group of phytochemicals responsible for the purple, blue or red hues of many plants, offer a market advantage. In addition, anthocyanin-rich foods are associated with protection against cardiovascular disease, thrombosis, diabetes, cancer, microbial-based disorders, neurological disorders, and vision ailments. However, the real health value of anthocyanins, whether as a natural colorant or a functional ingredient, is dependent on the ultimate bioaccessibility and bioavailability in the human body. Many animal and human clinical studies revealed that, after intake of anthocyanin-rich foods or anthocyanin extracts, only trace amounts (< 1% of ingested content) of anthocyanins or their predicted metabolites were detected in plasma after a standard blood draw, which was indicative of low bioavailability of anthocyanins. Protein binding to anthocyanins is a strategy that has recently been reported to enhance the ultimate bioactivity, bioaccessibility, and bioavailability of anthocyanins as compared to anthocyanins delivered without a protein carrier. Therefore, in this review, we address anthocyanin properties in food processing and digestion, anthocyanin-protein complexes used in food matrices, and changes in the bioaccessibility and bioavailability of anthocyanins when bound into anthocyanin-protein complexes in foods. Finally, we summarize the challenges and prospects of this delivery system for anthocyanin pigments.

Natural carriers: Recent advances in their use to improve the stability and bioaccessibility of food active compounds

In the last decades, the incorporation of bioactive compounds in food supplements aroused the attention of scientists. However, these ingredients often exhibit both low solubility and stability and their poor bioaccessibility within the gastrointestinal tract limits their effectiveness. To overcome these drawbacks, many carriers have been investigated for encapsulating nutraceuticals and enhancing their bioavailability. It is note that several different vegetable wall materials have been applied to build delivery systems. Considering their encapsulation mechanism, lipid and protein-based carriers display specific interaction patterns with bioactives, whereas polysaccharidic-based carriers can entrap them by creating porous highly stable networks. To maximize the encapsulation efficiency, mixed systems are very promising. Following the current goal of using natural and sustainable ingredients, only a limited number of studies about the isolation of new ingredients from agro-food waste are available. In this review, a comprehensive overview of the state of art in the development of innovative natural lipid-, protein- and polysaccharide-based plant carriers is presented, focusing on their application as food active compounds. Different aspects to be considered in the design of delivery systems are discussed, including the carrier structure and chemical features, the interaction between the encapsulating and the core material, and the parameters affecting bioactives entrapment.

Profile and activity of phenolic antioxidants in chrysanthemum (Huangshan Gongju) as affected by simulated digestions

The phenolics are the main bioactive substances of Huangshan Gongju, a famous chrysanthemum of China, but their digestive characteristics are still unknown. To explore the digestive properties of Huangshan Gongju phenolics, the flower was extracted and subjected to simulated digestions, and their phenolic profile and activity were analyzed. The results indicated that the total phenolics content and antioxidant activity of the extract varied with the simulated digestion steps, and they generally decreased in the oral and small intestine digestions but increased in the gastric digestion, and high correlations were detected between the total phenolics content and antioxidant activity (0.873 < r < 0.979, p < .01). The change of phenolic profile during the simulated digestions was similar to that of total phenolics content, and six individual phenolics were identified and quantified, and three of them, including chlorogenic acid, apigenin-7-O-rutinoside, and apigenin-7-O-6″-acetylglucoside showed higher recovery (>64.29%), implying they may be the main functional phenolics of Huangshan Gongju. PRACTICAL APPLICATIONS: This study proved that most phenolics in Huangshan Gongju were relatively stable during digestion. The finding may guarantee the application of Huangshan Gongju in the field of functional foods.

Bioactive properties and untargeted metabolomics analysis of bioaccessible fractions of non-fermented and fermented date fruit pomace by novel yeast isolates

In this study, attempts were made to utilize date by-product (date fruit pomace; DFP). This study aimed to investigate the health-promoting benefits of the fermented and non-fermented DFP before in vitro digestion and after (bioaccessible fraction). Untargeted metabolomic analyses for bioaccessible fractions were performed by UPLC-QTOF. DPPH percentages were 89.7%-90.3%, 90.1%-91.3%, and 90.8%-91.3% in the control, I. orientalis, and P. kudriazevii samples, respectively, before digestion; α-glucosidase inhibition before digestion was 1.9%-24.4%, 16.3%-30.0%, and 21.3%-31.3%, respectively; antimicrobial activities were 6.1%-13.3%, 13.7%-25.7%, and 20.6%-28.0% against E. coli O157:H7 and 2.2%-11.9%, 7.2%-20.7%, and 11.9%-29.2% against L. monocytogenes, respectively. The DPPH scavenging percentages were ∼63% lower in the bioaccessible fraction. The differentially regulated metabolites classes were benzene and derivatives, amino acids, peptides and analogs, organic acids, and phenols. This study revealed that the fermented DFP exhibited higher health properties than control.

Boosting the Bioaccessibility of Dietary Bioactives by Delivery as Protein-Polyphenol Aggregate Particles

Protein-polyphenol aggregate particles concurrently fortify a functional food product with healthy dietary proteins and concentrated polyphenols. However, what impact does ingestion of aggregate particles have on ultimate health relevance of either the polyphenolic molecules in the matrix or the protein molecules? Because human health benefits are contingent on bioavailability after ingestion, the fate of these molecules during transit in the gastrointestinal tract (GIT) will dictate their utility as functional food ingredients. This brief review explores diverse applications of protein-polyphenol particles in the food industry and the bioaccessibility of both bioactive polyphenolic compounds and edible proteins. Evidence to date suggests that complexation of phytoactive polyphenolics effectively enhances their health-relevant impacts, specifically because the phytoactives are protected in the protein matrix during transit in the GIT, allowing intact, non-degraded molecules to reach the colon for catabolism at the gut microbiome level, a prerequisite to realize the health benefits of these active compounds.

Spray-dried and freeze-dried protein-spinach particles; effect of drying technique and protein type on the bioaccessibility of carotenoids, chlorophylls, and phenolics

The effects of protein carrier and drying technique on the concentration and bioaccessibility of lipophilic compounds (lutein, β-carotene, chlorophylls a and b) and hydrophilic flavonoids in freeze-dried (FD) or spray-dried (SD) spinach juice and protein-spinach particles were investigated. Carotenoid and chlorophyll contents were highest in FD spinach juice without protein (147 and 1355 mg/100 g, respectively). For both SD and FD protein-spinach particles, SPI best protected carotenoids and chlorophylls (123 and 1160 mg/g, respectively), although the bioaccessibility of lipophilic compounds in WPI particles was higher than SPI particles (p < 0.05). For flavonoids, the drying technique was more important than the type of carrier, since FD particles had higher total flavonoids than SD. However, SD particles had higher bioaccessibility for most flavonoids (40-90 %) compared to FD (<20 %). The drying method and protein carrier can be designed to produce protein-spinach ingredients with desired concentration of compounds and bioaccessibility.

Effects of Marine Bioactive Compounds on Gut Ecology Based on In Vitro Digestion and Colonic Fermentation Models

Digestion and the absorption of food compounds are necessary steps before nutrients can exert a role in human health. The absorption and utilization of nutrients in the diet is an extremely complex dynamic process. Accurately grasping the digestion and absorption mechanisms of different nutrients or bioactive compounds can provide a better understanding regarding the relationship between health and nutrition. Several in vitro models for simulating human gastrointestinal digestion and colonic fermentation have been established to obtain more accurate data for further understanding of the metabolism of dietary components. Marine media is rich in a wide variety of nutrients that are essential for humans and is gaining increased attention as a research topic. This review summarizes some of the most explored in vitro digestion and colonic fermentation models. It also summarizes the research progress on the digestion and absorption of nutrients and bioactive compounds from marine substrates when subjected to these in vitro models. Additionally, an overview of the changes imparted by the digestion process on these bioactive compounds is provided, in order to support those marine resources that can be utilized for developing new healthy foods.

Fruit Juice Industry Wastes as a Source of Bioactives

Food processing sustainability, as well as waste minimization, are key concerns for the modern food industry. A significant amount of waste is generated by the fruit juice industry each year. In addition to the economic losses caused by the removal of these wastes, its impact on the environment is undeniable. Therefore, researchers have focused on recovering the bioactive components from fruit juice processing, in which a great number of phytochemicals still exist in the agro-industrial wastes, to help minimize the waste burden as well as provide new sources of bioactive compounds, which are believed to be protective agents against certain diseases such as cardiovascular diseases, cancer, and diabetes. Although these wastes contain non-negligible amounts of bioactive compounds, information on the utilization of these byproducts in functional ingredient/food production and their impact on the sensory quality of food products is still scarce. In this regard, this review summarizes the most recent literature on bioactive compounds present in the wastes of apple, citrus fruits, berries, stoned fruits, melons, and tropical fruit juices, together with their extraction techniques and valorization approaches. Besides, on the one hand, examples of different current food applications with the use of these wastes are provided. On the other hand, the challenges with respect to economic, sensory, and safety issues are also discussed.

A New Polysaccharide Carrier Isolated from Camelina Cake: Structural Characterization, Rheological Behavior, and Its Influence on Purple Corn Cob Extract's Bioaccessibility

A polysaccharide fraction obtained from camelina cake (CCP), selected as a carrier to encapsulate purple corn cob extract (MCE), was investigated. A wide population of carbohydrate polymers (with a polydispersivity index of 3.26 ± 0.07 and an average molecular weight of about 139.749 × 103 ± 4.392 × 10³ g/mol) with a gel-like behavior and a thixotropic feature characterized the fraction. MCE-CCP combinations (50–50 and 25–75, w/w), selected based on CCP encapsulation efficiency, were tested for their stability and MCE polyphenols’ bioaccessibility during digestion (monitored using an in vitro static procedure). During the oral and gastric phases of the digestion process, CCP gradually swelled and totally released MCE polyphenols. MCE-CCP50 had the fastest release. Moreover, anthocyanins were still detectable during the duodenal phase, in both MCE-CCP ingredients. Furthermore, CCP (5 mg/mL) exerted in vitro potential hypocholesterolemic activity via bile salts binding during digestion.

Fiber-Rich Cranberry Pomace as Food Ingredient with Functional Activity for Yogurt Production

In this study, different amounts (from 2% to 4.5%) of dietary fiber-rich cranberry pomace (CP) were added to yogurt before or after fermentation to increase dietary fiber content without changing the textural properties of the product. The addition of CP reduced whey loss, improved the firmness and viscosity, increased the total phenol compound content and the antioxidant capacity values (DPPH•, ABTS, and ORAC) of the yogurt in a dose-dependent manner, and had no significant effect on the viability of the yogurt culture bacteria. For all CP-supplemented yogurt samples, the bioaccessibility index of the polyphenols after in vitro intestinal phase digestion was approximately 90%. However, yogurt with CP added before fermentation exhibited a significantly (p < 0.05) lower degree of protein hydrolysis post-gastric and post-intestinal than the yogurt with CP added after fermentation. Yogurt supplemented with 4.5% CP could be considered a good antioxidant dairy product and a good source of dietary fiber.

Biofortified Whey/Deglycosylated Whey and Chickpea Protein Matrices: Functional Enrichment by Black Mulberry Polyphenols

Morus nigra L. (black mulberry-BM) is a promising nutraceutical fruit containing biologically active polyphenols like anthocyanins, proanthocyanidins, catechins, and stilbenes, with well-established anti-inflammatory, antidiabetic, anti-obesity, and anticancer biofunctions. However, these health-promoting properties in raw fruit are greatly masked due to the presence of soluble and insoluble carbohydrates in excess amounts restricting daily intake of the required dose to achieve targeted effects. In the current study, different protein sources (defatted whey and chickpea flours) were optimized through different conditions to capture polyphenols from BM juice while diminishing its glucose content. To optimize polyphenol-protein interactions, various pHs (3.7, 4.2, and 4.7), matrix concentrations (20, 50, and 80 g protein/L), and incubation times (5, 20, and 45 min) were tested. In the present work, optimized BM polyphenol enriched whey matrix inhibited pro-inflammatory mediators and promoted Nrf-2 dependent cytoprotective enzyme expressions in lipopolysaccharide (LPS) induced macrophages at low doses. In addition, whey proteins were also subjected to an enzymatic deglycosylation process by using recently identified EndoBI-1 enzyme for the specific cleavage of N-glycan core in all glycan types including high mannoses, hybrids as well as complex glycans found on defatted whey proteins. After this process, the polyphenol sorption capacity of deglycosylated whey proteins was found to be significantly higher (37%) than the capacity of non-treated normal whey protein under optimized conditions. In conclusion, deglycosylation of protein matrices could be a novel strategy for efficient sorption/concentration of polyphenols from fruits and vegetables, however, more detailed studies are needed to understand this effect.

Plant-Based Support of Respiratory Health during Viral Outbreaks

Respiratory viruses are linked to major epidemic events that have plagued humans through recorded history and possibly much earlier, ranging from common colds, influenza, and coronavirus infections to measles. However, difficulty in developing effective pharmaceutical solutions to treat infected individuals has hindered efforts to manage and minimize respiratory viral outbreaks and the associated mortality. Here we highlight a series of botanical interventions with different and often overlapping putative mechanisms of action to support the respiratory system, for which the bioactive pharmacophore was suggested and the initial structure-activity relationships have been explored (Bupleurum spp., Glycyrrhiza spp., Andrographis spp.), have been proposed with uncertainty (Echinacea spp., Zingiber spp., Verbascum spp., Marrubium spp.), or remained to be elucidated (Sambucus spp., Urtica spp.). Investigating these metabolites and their botanical sources holds potential to uncover new mediators of the respiratory health outcomes as well as molecular targets for future break-through therapeutic interventions targeting respiratory viral outbreaks.

Bioaccessibility of Anthocyanins on in vitro Digestion Mmodels: Factors Implicated and Role in Functional Foods Development

BACKGROUND

Worldwide, the prevalence of obesity and related non-communicable chronic diseases is high and continues to grow. In that sense, anthocyanins (ANC) have shown beneficial health effects in preventing obesity and metabolic risk factors. Moreover, the demand for functional foods incorporating these compounds has risen significantly in the past years. Thus, there is a need for validations of the functional properties of these formulations; nevertheless, in vivo assays are complex and require a lot of resources. One approach for estimating bioactive compounds' functionality and health benefits is to evaluate their bioaccessibility on a specific food matrix, determined by various factors. This article aims to review different factors influencing the bioaccessibility of ANC evaluated on in vitro digestion models as a functionality parameter, elucidating the effect of chemical composition, raw materials, food matrices, and vehicles for the delivery of ANC.

METHODS

Study searches were performed using PubMed, Web of Science, Scopus, and Science Direct databases.

RESULTS

Different factors influenced bioaccessibility and stability of ANC studied by in vitro digestion which are: i) the raw material used for ANC obtention; ii) food processing; iii) other food components; iv) the extraction method and solvents used; v) the structure of ANC; vi) delivery system (e.g., microencapsulation); vii) pH of the medium; viii) the digestion stage.

CONCLUSION

Simulated digestion systems allow to determine free or encapsulated ANC bioaccessibility in different food matrices, which offers advantages in determining the potential functionality of a food product.

The Effects of Blueberry Phytochemicals on Cell Models of Inflammation and Oxidative Stress

Blueberries have been extensively studied for the health benefits associated with their high phenolic content. The positive impact of blueberry consumption on human health is associated in part with modulation of proinflammatory molecular pathways and oxidative stress. Here, we review in vitro studies examining the anti-inflammatory and antioxidant effects of blueberry phytochemicals, discuss the results in terms of relevance to disease and health, and consider how different blueberry components modulate cellular mechanisms. The dampening effects of blueberry-derived molecules on inflammation and oxidative stress in cell models have been demonstrated through downregulation of the NF-κB pathway and reduction of reactive oxygen species (ROS) and lipid peroxidation. The modulatory effects of blueberry phytochemicals on the mitogen-activated protein kinase (MAPK) pathway and antioxidant system are not as well described, with inconsistent observations reported on immune cells and between models of endothelial, dermal, and ocular inflammation. Although anthocyanins are often reported as being the main bioactive compound in blueberries, no individual phytochemical has emerged as the primary compound when different fractions are compared; rather, an effect of whole blueberry extracts or synergy between different phenolic and nonphenolic extracts seems apparent. The major molecular mechanisms of blueberry phytochemicals are increasingly defined in cell models, but their relevance in more complex human systems needs further investigation using well-controlled clinical trials, in which systemic exposures to blueberry-associated molecules are measured concurrently with physiologic indices of inflammation and oxidative stress.

Catechin Inhibits the Release of Advanced Glycation End Products during Glycated Bovine Serum Albumin Digestion and Corresponding Mechanisms In Vitro

Glycated proteins are the main source of dietary advanced glycation end products (AGEs). Glycated proteins are enzymatically hydrolyzed in the gastrointestinal tract, which releases more absorbable and smaller potentially harmful AGEs. This study investigated the inhibitory effect of catechin on AGE release from glycated bovine serum albumin (G-BSA) during gastrointestinal digestion. Catechin inhibited AGE release during gastrointestinal digestion, especially in the gastric digestion stage. Additionally, catechin altered these peptides in the small intestine by reducing G-BSA digestibility. The proposed mechanism involves interactions between catechin and G-BSA/digestive enzymes, inhibiting digestive enzyme activity and changing the conformation of G-BSA. Catechin reduced G-BSA β-sheet content and protected the helical conformation. Moreover, catechin enhanced the antioxidant capacity of G-BSA, which could attenuate postprandial oxidative stress in the gastrointestinal tract caused by the release of AGEs. This study improves our understanding of the nutritional and health effects of catechin on dietary AGEs during gastrointestinal digestion.

Slow digestion-oriented dietary strategy to sustain the secretion of GLP-1 for improved glucose homeostasis

Dysregulated glucose metabolism is associated with many chronic diseases such as obesity and type 2 diabetes mellitus (T2DM), and strategies to restore and maintain glucose homeostasis are essential to health. The incretin hormone of glucagon-like peptide-1 (GLP-1) is known to play a critical role in regulating glucose homeostasis and dietary nutrients are the primary stimuli to the release of intestinal GLP-1. However, the GLP-1 producing enteroendocrine L-cells are mainly distributed in the distal region of the gastrointestinal tract where there are almost no nutrients to stimulate the secretion of GLP-1 under normal situations. Thus, a dietary strategy to sustain the release of GLP-1 was proposed, and the slow digestion property and dipeptidyl peptidase IV (DPP-IV) inhibitory activity of food components, approaches to reduce the rate of food digestion, and mechanisms to sustain the release of GLP-1 were reviewed. A slow digestion-oriented dietary approach through encapsulation of nutrients, incorporation of viscous dietary fibers, and enzyme inhibitors of phytochemicals in a designed whole food matrix will be implemented to efficiently reduce the digestion rate of food nutrients, potentiate their distal deposition and a sustained secretion of GLP-1, which will be beneficial to improved glucose homeostasis and health.

Impact of Wall Materials on Physico-Chemical Properties and Stability of Eggplant Peels Anthocyanin Hydrogels

In this study, eggplant peel extract was used to obtain hydrogels. Two experimental variants were realized by varying the wall materials. Whey proteins isolate (WPI), citrus pectin (P), and sodium carboxymethylcellulose (CMCNa) were used as wall materials. The microcapsules were obtained by the gelation technique, followed by freeze-drying in order to obtain powders. Both experimental variants were analyzed in terms of phytochemical content, antioxidant activity, storage stability, and in vitro digestibility. Additionally, confocal microscopy was used to observe the encapsulation of the bioactive compounds from the eggplant peel extract into the selected matrices. The encapsulation efficiency of the powders varied from 64.67 ± 0.68% for variant 1 (V1) to 96.44 ± 3.43% for variant 2 (V2). Both powders presented high bioactive compound content with high antioxidant activity. V2 showed the highest stability within 28 days of storage, but also in the simulated digestive system.

Antioxidant activities of chlorogenic acid derivatives with different acyl donor chain lengths and their stabilities during in vitro simulated gastrointestinal digestion

In this study, chlorogenic acid (CA) was acylated with vinyl esters of different carbon chain lengths under the action of the lipase Lipozyme RM. Five CA derivatives (C2-CA, C4-CA, C6-CA, C8-CA, and C12-CA) with different lipophilicities were obtained, and their digestive stabilities and antioxidant activities were evaluated. The lipophilicities were positively correlated with the digestive stabilities of CA derivatives. The antioxidant activities of CA derivatives did not change with the reduction of phenolic hydroxyl groups, and their capacity to scavenge 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+•) and 1,1-diphenyl-2-picrylhydrazyl (DPPH•) were similar to those of CA. In cellular antioxidant activity (CAA) tests, it was found that the capacity of these derivates to cross cell membranes were enhanced upon enhancing lipophilicity, and their antioxidant activities were improved. C12-CA showed the best antioxidant activity with a median effective dose (EC50) of 9.40 μg/mL, which was significantly lower than that of CA (i.e., 29.08 μg/mL).

Can Natural Products Exert Neuroprotection without Crossing the Blood-Brain Barrier?

The scope of evidence on the neuroprotective impact of natural products has been greatly extended in recent years. However, a key question that remains to be answered is whether natural products act directly on targets located in the central nervous system (CNS), or whether they act indirectly through other mechanisms in the periphery. While molecules utilized for brain diseases are typically bestowed with a capacity to cross the blood–brain barrier, it has been recently uncovered that peripheral metabolism impacts brain functions, including cognition. The gut–microbiota–brain axis is receiving increasing attention as another indirect pathway for orally administered compounds to act on the CNS. In this review, we will briefly explore these possibilities focusing on two classes of natural products: omega-3 polyunsaturated fatty acids (n-3 PUFAs) from marine sources and polyphenols from plants. The former will be used as an example of a natural product with relatively high brain bioavailability but with tightly regulated transport and metabolism, and the latter as an example of natural compounds with low brain bioavailability, yet with a growing amount of preclinical and clinical evidence of efficacy. In conclusion, it is proposed that bioavailability data should be sought early in the development of natural products to help identifying relevant mechanisms and potential impact on prevalent CNS disorders, such as Alzheimer’s disease.