Investigating the effects of food matrix and food components on bioaccessibility of pomegranate (Punica granatum) phenolics and anthocyanins using an in-vitro gastrointestinal digestion model

The Bioaccessibility of Grape-Derived Phenolic Compounds: An Overview

Grape-derived phenolic compounds possess many health benefits, but their biological effectiveness and their effects on human health depend directly on bioaccessibility. Different physiological conditions, interactions with food compounds (proteins, lipids, and carbohydrates), and/or microbial transformations affect the solubilization and stability of phenolic compounds, thus altering their bioaccessibility and biological activity. Previously published review articles on grape-derived phenolic compounds have focused on characterization, transformation during winemaking, various applications, and health benefits, but the literature lacks a comprehensive overview of the bioaccessibility of these compounds during gastrointestinal digestion. In this context, models of gastrointestinal digestion and factors affecting the bioaccessibility of phenolic compounds were considered to understand the behavior of grape-derived phenolic compounds during digestion in the absence or presence of different food matrices. Finally, this review should enable the development of novel food products with targeted bioaccessibility of grape-derived phenolic compounds.

Nano techniques: an updated review focused on anthocyanin stability

Anthocyanins (ACNs) are one of the subgroups of flavonoids and getting intensive attraction due to the nutritional values. However, their application of ACNs is limited due to their poor stability and bioavailability. Accordingly, nanoencapsulation has been developed to enhance its stability and bio-efficacy. This review focuses on the nano-technique applications of delivery systems that be used for ACNs stabilization, with an emphasis on physicochemical stability and health benefits. ACNs incorporated with delivery systems in forms of nano-particles and fibrils can achieve advanced functions, such as improved stability, enhanced bioavailability, and controlled release. Also, the toxicological evaluation of nano delivery systems is summarized. Additionally, this review summarizes the challenges and suggests the further perspectives for the further application of ACNs delivery systems in food and medical fields.

The galactomannan-EGCG physical complex: Effect of branching degree and molecular weight on structural and physiological properties

Polysaccharides and polyphenols are bioactive components that co-exist in many plant foods. Their binary interaction in terms of the structure-function relationships, however, has not been well clarified. This study elucidated the correlation between the structural and physiological properties of galactomannan (GM) -catechin monomer complexes and GM with different branching or molecular weight (Mw). Results indicated that locus bean gum with lower branching degree (Gal/Man is 0.259) bound more readily to EGCG with adsorption rate of 19.42 %. EGCG and ECG containing galloyl groups were more inclined to form hydrogen bonds with GMs, significantly improving the adsorption by GMs. The introduction of EGCG could enhance the antioxidant activity and starch digestion inhibition of GM, which positively correlated with the adsorption capacity of EGCG. The guar gum (GG) with higher Mw (7384.3 kDa) could transport 71.51 % EGCG into the colon, while the retention rate of EGCG reaching the colon alone was only 46.33 %. Conversely, GM-EGCG complex with lower Mw (6.9 kDa) could be readily utilized by gut microbiota, and increased production of short-chain fatty acids (SCFAs). This study elucidated the structure-properties relationship of GM-EGCG complexes, and provide a new idea for the development and precision nutrition of polysaccharides-polyphenol complexes fortified functional foods.

Interactions of White Mugwort (Artemisia lactiflora Wall.) Extract with Food Ingredients during In Vitro Gastrointestinal Digestion and Their Impact on Bioaccessibility of Polyphenols in Various Model Systems

The bioaccessibility of phytochemicals is an important factor for new functional food design. The interaction of white mugwort extract (FE) and food ingredients (coconut oil, egg white albumen, brown rice powder, inulin, and mixtures thereof) was determined after in vitro digestion to inform the development of a functional soup for an aging population. Coconut oil exerted a protective effect on polyphenols, showing the highest bioaccessibility (62.9%) and antioxidant activity after intestinal digestion (DPPH 12.38 mg GAE/g DW, FRAP 0.88 mol Fe(ll)/g DW). In contrast, egg white albumen had the most significant negative effect on the polyphenol stability, resulting in the lowest bioaccessibility (12.49%). Moreover, FE promoted the emulsion stability and delayed starch digestion by inhibiting amylase activity via non-specific polyphenol-protein interactions, resulting in a decrease in the total reducing sugars (TRS) released during digestion. It also limited the protein digestion, probably due to the complex formation of polyphenols and proteins, consequently reducing the bioaccessibility of both amino acids and polyphenols. These findings provide useful information for designing functional food products that could promote the bioaccessibility and bioactivity of natural extracts.

Alginate beads loaded with rambutan extract: characterization and stability during in vitro gastrointestinal digestion

BACKGROUND

Fallen young rambutan fruit is an underrated agricultural waste which may contain several bioactive compounds. In this study, fallen young rambutan fruit was assessed regarding its phenolic contents and antioxidant activities. In order to expand its utilization, rambutan extract-loaded hydrogel beads were developed by a basic spherification technique using sodium alginate. The effect of ratios of polymer and extract and different calcium sources were evaluated. The recovery of bioactive compounds from the hydrogel beads was determined using in vitro gastrointestinal digestion models.

RESULTS

Use of 50% (v/v) ethanol yielded rambutan extract with good chemical properties. The production of hydrogel beads using a ratio of 1:3 with calcium lactate provided the highest production yield of 122.94%. The hydrogel beads developed using the ratio of 1:3 with a combination of calcium lactate and calcium chloride showed high recovery of phenolic compounds and antioxidant activity after simulated intestinal digestion, which were greater compared to unencapsulated extract.

CONCLUSION

The findings demonstrate that the ratio of wall material to rambutan extract and the calcium source influence the physical properties, chemical properties and in vitro gastrointestinal digestion stability of alginate beads. The obtained hydrogel beads may have potential for application in the food or pharmaceutical industries. © 2024 Society of Chemical Industry.

Roasted yerba mate (Ilex paraguariensis) infusions in bovine milk model before and after in vitro digestion: Bioaccessibility of phenolic compounds, antioxidant activity, protein-polyphenol interactions and bioactive peptides

Yerba mate is increasingly acknowledged for its bioactive properties and is currently being incorporated into various food and pharmaceutical products. When roasted, yerba mate transforms into mate tea, consumed as a hot aqueous infusion, and has gained popularity. This study investigated the bioaccessibility of phenolic compounds, protein-polyphenol interactions, antioxidant activity, and bioactive peptides in roasted yerba mate infusions, utilizing whole, semi-skimmed, and skimmed bovine milk models. The phytochemical profile of roasted yerba mate was analyzed in infusions with water and milk (whole, semi-skimmed, and skimmed), before and after in vitro digestion, identifying 18 compounds that exhibited variations in composition and presence among the samples. Bioavailability varied across different milk matrices, with milk being four times more efficient as a solvent for extraction. Gastric digestion significantly impacted (p < 0.05) the release of phenolic compounds, such as chlorogenic acid and rutin, with only chlorogenic acid remaining 100 % bioavailable in the infusion prepared with skimmed milk. Protein-polyphenol interaction did not influence protein digestion in different infusions, as there was a similarity in the hydrolysis pattern during the digestive process. Changes in antioxidant activity during digestion phases, especially after intestinal digestion in milk infusions, were related to alterations in protein structures and digestive interactions. The evaluation of total phenolic compounds highlighted that skimmed milk infusion notably preserved these compounds during digestion. Peptidomic analysis identified 253, 221, and 191 potentially bioactive peptides for whole, semi-skimmed, and skimmed milk-digested infusions, respectively, with a focus on anti-inflammatory and anticancer activities, presenting a synergistic approach to promote health benefits. The selection of milk type is crucial for comprehending the effects of digestion and interactions in bioactive compound-rich foods, highlighting the advantages of consuming plant infusions prepared with milk.

Effects of Matrix Structure on Protein Digestibility and Antioxidant Property of Different Soybean Curds During In Vitro Digestion

This study compared the three most common types of tofu (soybean curd), which were prepared by using magnesium chloride (MgCl2 tofu), calcium sulfate (CaSO4 tofu), and glucono-δ-lactone (GDL tofu) coagulants. The results showed that GDL tofu had a higher water holding capacity than MgCl2 tofu and CaSO4 tofu, which was attributed to its high surface hydrophobicity and disulfide bond content. GDL tofu possessed the lowest firmness, gumminess, and chewiness, along with a uniform network structure and a thin protein matrix. In contrast, MgCl2 tofu exhibited an inhomogeneous network structure with a thick protein matrix. Combining the results of protein hydrolysis degree, SDS-PAGE, and free amino acids during in vitro digestion, it was indicated that the degree of protein digestion in GDL tofu was the highest. After intestinal digestion, GDL tofu had the highest total phenolic content, ferric reducing antioxidant power, and DPPH value. These results demonstrated the superior protein digestibility and antioxidant property of GDL tofu during in vitro digestion due to its structural characteristics that facilitate enzyme diffusion in the matrix. The findings offer insight into the protein digestibility and antioxidant properties of different types of tofu during digestion from structural characteristic perspective and valuable reference information for consumer dietary nutrition.

Biological activity of optimized phenolic extracts of quince (Cydonia oblonga Miller) parts before and after simulated in vitro gastrointestinal digestion

In this study, the phenolic extracts of Eşme quince parts (pulp, peel, seed, juice, and leaf) were obtained under optimized extraction conditions. Then, the total phenolic content (TPC), the quantities of main phenolic compounds, antioxidant, and antimicrobial activity and the change in bioactivity properties (TPC, antioxidant capacity, and antimicrobial activity on the same sixteen microorganisms) after in vitro digestion of each quince part were evaluated. The order of TPC and antioxidant activity was determined as leaf > peel > juice > pulp > seed. After in vitro gastrointestinal digestion, a decrease was observed for the TPC (average 5-fold reduction) and antioxidant activity (more than 2.5-fold reduction) in all quince parts except quince seed than their extract forms. The quince leaf extract exhibited the highest antibacterial activity. Overall, this study exhibited that the quince leaf was considered a promising, cheap, and natural source for nutritional or pharmaceutical applications with biological activity properties.

A Novel Approach to Serving Plant-Based Confectionery-The Employment of Spray Drying in the Production of Carboxymethyl Cellulose-Based Delivery Systems Enriched with Teucrium montanum L. Extract

In this study, spray drying was used as a technological solution for the valorization of Teucrium montanum extract into carboxymethyl cellulose-based delivery systems (CMC), individually or in combination with collagen, guar gum, gum arabic, and kappa-carrageenan. The results showed that the process yield and morphological properties were positively influenced by the introduction of CMC binary blends. The employment of CMC resulted in a high encapsulation efficiency (77-96%) for all phenylethanoid glycosides (PGs) analyzed. Due to the low wettability of the microparticles, a relatively gradual in vitro release of the PGs was achieved. Infusion of the filling with hydrophilic T. montanum extract encapsulated in microparticles with high hydrophobic surface area proved to be a practical route for significant confectionery fortification (5-9 mg PGs per dw serving), ensuring prolonged interaction between the food matrix used and the extract under simulated gastrointestinal conditions. Based on sensory evaluation, the introduction of kudzu starch into the jelly matrix has shown a texture-modifying potential.

Exploring the Transmembrane Behaviors of Dietary Flavonoids under Intestinal Digestive Products of Different Lipids: Insights into the Structure-Activity Relationship In Vitro

This study aimed to investigate the transmembrane transport behavior and structure-activity relationships of various dietary flavonoids in the presence of dietary lipids derived from different sources in vitro. Results revealed that the digestion products of soybean oil (SOED) and lard (LOED) augmented the apparent permeability coefficients of most dietary flavonoids, and SOED exhibited higher transport compared with LOED. The structural properties of flavonoids and the potential interactions between fatty acids in these digestion products and flavonoids may influence the outcomes. 3D quantitative structure-activity relationship analyses revealed that incorporating small-volume groups at position 8 of the A-ring augmented the transmembrane transfer of flavonoids in the LOED system compared with the control group. By contrast, the integration of hydrophobic groups at position 5 of the A-ring and hydrogen bonding acceptor groups at position 6 of the A-ring enhanced the transmembrane transportation of flavonoids in the SOED system. Molecular dynamics simulations revealed that the SOED system may facilitate the interactions with flavonoids to form more stable and compact fatty acid-flavonoid complexes compared to the LOED system. These findings may provide valuable insights into flavonoid absorption to facilitate the development and utilization of functional foods or dietary supplements based on dietary flavonoids.

Characterization and bioaccessibility assessment of bioactive compounds from camu-camu (Myrciaria dubia) powders and their food applications

Camu-camu (Myrciaria dubia) is a tropical fruit known for its content of bioactive compounds. This study aimed to evaluate physicochemically, morphologically, andsensorialpowders from camu-camu obtained by spray-drying at two inlet temperatures (150 °C and 180 °C) with three encapsulating agents (maltodextrin, whey protein and a 50:50 mixture of both) and by freeze-drying of whole fruit. The use of maltodextrin protected bet anthocyanins (cyanidin-3-glucoside (C3G) and delphinidin-3-glucoside (D3G)), but whey protein showed a better protective effect on ascorbic and malic acids. These facts were confirmed during the storage stability test, finding that relative humidity is a critical variable in preserving the bioactive compounds of camu-camu powders. The powders with the highest content of bioactive compounds were added to a yogurt and a white grape juice, and then sensory evaluated. The bioaccessibility studies in gastric and intestinal phases showed better recovery percentages of bioactive compounds in camu-camu powders (up to 60.8 %) and beverages (up to 90 %) for C3G, D3G, ascorbic acid, and malic acid than in the fruit juice. Dehydration of camu-camu (M. dubia) is a strategy to increase the bioactive compounds stability, modulate the fruit sensory properties, and improve their bioavailability after incorporation in food matrices.

Bioaccessibility data of potentially toxic elements in complementary foods for infants: A review

The introduction of complementary foods (CFs) is a critical step in an infant's transition to solid foods, providing essential nutrients beyond breast milk. However, CFs may contain potentially toxic elements (PTEs), such as arsenic and cadmium that pose health risks to infants. In this context, understanding the bioaccessibility of PTEs is vital as it determines the fraction of a contaminant released from the food matrix and available for absorption in the gastrointestinal tract. Efforts have been made to standardize the assessment methodology for bioaccessibility, ensuring consistent and reliable data. Moreover, regulatory agencies have established guidelines for PTEs levels in food. However, important gaps still exist, which motivates many research opportunities on this topic.

Influence of spontaneous and inoculated fermentation of açai on simulated digestion, antioxidant capacity and cytotoxic activity

This work describes the kinetic study of different types (spontaneous, lactic and alcoholic) of açai fermentation in terms of total phenolics and total anthocyanins, as well as antioxidant capacity, before and after simulated digestion (SD). Cytotoxicity (A549, HCT8 and IMR90 cells) and formation of reactive oxygen species (A549 cells) were also evaluated. The results revealed that spontaneous fermentation (SF) for 24 h, followed by SD, generated a product with greater bioaccessibility of phenolics (52.68%) and cyanidin-3-glucoside (27.01%) than unfermented açai. Likewise, lactic fermentation (LF) for 72 h improved the bioavailability of phenolics (64.49%) and cyanidin-3-rutinoside (20.00%). On the other hand, alcoholic fermentation (AF) decreased the bioaccessibility of phenolic compounds and anthocyanins after SD. The SF 24 h (10.16 ± 1.25 μmol Trolox /g) and LF 72 h (15.90 ± 0.51 μmol Trolox /g) significantly increased the antioxidant capacity after SD, when compared to unfermented açai (SF 0 h, 4.00 ± 0.09 μmol Trolox /g; LF 0 h, 10.57 ± 0.91 μmol Trolox /g). It was concluded that the samples did not show cytotoxicity in the cell lines tested and, in addition, AF 24 h showed antioxidant and antimutagenic effects in vitro, reducing about 40% of chromosomal aberrations. The results obtained provide important information that can be used to produce foods with greater bioaccessibility of bioactive compounds.

The Effect of a High-Protein Diet Supplemented with Blackthorn Flower Extract on Polyphenol Bioavailability and Antioxidant Status in the Organs of C57BL/6 Mice

The health benefits of polyphenols are based on their bioavailability, which is why a significant portion of research focuses on factors that affect their bioavailability. Previous studies suggest that the intake of polyphenols along with macronutrients in food represents one of the key factors influencing the bioavailability of polyphenols and, consequently, their biological activity in the organism. Since polyphenols in the human diet are mainly consumed in food together with macronutrients, this study investigated the in vivo absorption, metabolism, and distribution of polyphenolic compounds from the water extract of blackthorn flower (Prunus spinosa L.) in combination with a protein-enriched diet in the organs (small intestine, liver, kidney) of C57BL/6 mice. The bioaccumulation of polyphenol molecules, biologically available maximum concentrations of individual groups of polyphenol molecules, and their effect on the oxidative/antioxidative status of organs were also examined. The results of this study indicate increased bioabsorption and bioavailability of flavan-3-ols (EC, EGCG) and reduced absorption kinetics of certain polyphenols from the groups of flavonols, flavones, and phenolic acids in the organs of C57BL/6 mice after intragastric administration of the water extract of blackthorn flower (Prunus spinosa L.) in combination with a diet enriched with whey proteins. Furthermore, subchronic intake of polyphenols from the water extract of blackthorn flower (Prunus spinosa L.) in combination with a diet enriched with whey proteins induces the synthesis of total glutathione (tGSH) in the liver and superoxide dismutase (SOD) in the liver and small intestine. The results of this study suggest potential applications in the development of functional foods aimed at achieving the optimal health status of the organism and the possibility of reducing the risk of oxidative stress-related disease.

Food matrix-flavonoid interactions and their effect on bioavailability

Flavonoid compounds exhibit a wide range of health benefits as plant-derived dietary components. Typically, co-consumed with the food matrix,they must be released from the matrix and converted into an absorbable form (bioaccessibility) before reaching the small intestine, where they are eventually absorbed and transferred into the bloodstream (bioavailability) to exert their biological activity. However, a large number of studies have revealed the biological functions of individual flavonoid compounds in different experimental models, ignoring the more complex but common relationships established in the diet. Besides, it has been appreciated that the gut microbiome plays a crucial role in the metabolism of flavonoids and food substrates, thereby having a significant impact on their interactions, but much progress still needs to be made in this area. Therefore, this review intends to comprehensively investigate the interactions between flavonoids and food matrices, including lipids, proteins, carbohydrates and minerals, and their effects on the nutritional properties of food matrices and the bioaccessibility and bioavailability of flavonoid compounds. Furthermore, the health effects of the interaction of flavonoid compounds with the gut microbiome have also been discussed.HIGHLIGHTSFlavonoids are able to bind to nutrients in the food matrix through covalent or non-covalent bonds.Flavonoids affect the digestion and absorption of lipids, proteins, carbohydrates and minerals in the food matrix (bioaccessibility).Lipids, proteins and carbohydrates may favorably affect the bioavailability of flavonoids.Improved intestinal flora may improve flavonoid bioavailability.

Deciphering the interactions between lipids and red wine polyphenols through the gastrointestinal tract

This paper investigates the mutual interactions between lipids and red wine polyphenols at different stages of the gastrointestinal tract by using the simgi® dynamic simulator. Three food models were tested: a Wine model, a Lipid model (olive oil + cholesterol) and a Wine + Lipid model (red wine + olive oil + cholesterol). With regard to wine polyphenols, results showed that co-digestion with lipids slightly affected the phenolic profile after gastrointestinal digestion. In relation to lipid bioaccessibility, the co-digestion with red wine tended to increase the percentage of bioaccessible monoglycerides, although significant differences were not found (p > 0.05). Furthermore, co-digestion with red wine tended to reduce cholesterol bioaccessibility (from 80 to 49 %), which could be related to the decrease in bile salt content observed in the micellar phase. For free fatty acids, almost no changes were observed. At the colonic level, the co-digestion of red wine and lipids conditioned the composition and metabolism of colonic microbiota. For instance, the growth [log (ufc/mL)] of lactic acid bacteria (6.9 ± 0.2) and bifidobacteria (6.8 ± 0.1) populations were significantly higher for the Wine + Lipid food model respect to the control colonic fermentation (5.2 ± 0.1 and 5.3 ± 0.2, respectively). Besides, the production of total SCFAs was greater for the Wine + Lipid food model. Also, the cytotoxicity of the colonic-digested samples towards human colon adenocarcinoma cells (HCT-116 and HT-29) was found to be significantly lower for the Wine and Wine + Lipid models than for the Lipid model and the control (no food addition). Overall, the results obtained using the simgi® model were consistent with those reported in vivo in the literature. In particular, they suggest that red wine may favourably modulate lipid bioaccessibility - a fact that could explain the hypocholesterolemic effects of red wine and red wine polyphenols observed in humans.

Impact of Starch-Rich Food Matrices on Black Rice Anthocyanin Accessibility and Carbohydrate Digestibility

Anthocyanins reduce starch digestibility via carbohydrase-inhibitory pathways, but food matrix effects during digestion may also influence its enzymatic function. Understanding anthocyanin-food matrix interactions is significant as the efficiency of carbohydrase inhibition relies on anthocyanin accessibility during digestion. Therefore, we aimed to evaluate the influence of food matrices on black rice anthocyanin accessibility in relation to starch digestibility in common settings of anthocyanin consumption-its co-ingestion with food, and consumption of fortified food. Our findings indicate that black rice anthocyanin extracts (BRAE) had reduced intestinal digestibility of bread to a larger extent for the co-digestion of BRAE with bread (39.3%) (4CO), than BRAE-fortified bread (25.9%) (4FO). Overall anthocyanin accessibility was about 5% greater from the co-digestion with bread than fortified bread across all digestion phases. Differences in anthocyanin accessibility were also noted with changes to gastrointestinal pH and food matrix compositions-with up to 10.1% (oral to gastric) and 73.4% (gastric to intestinal) reductions in accessibility with pH changes, and 3.4% greater accessibility in protein matrices than starch matrices. Our findings demonstrate that the modulation of starch digestibility by anthocyanin is a combined result of its accessibility, food matrix composition, and gastrointestinal conditions.

Assessing differences in the bioaccessibility of phenolics present in two wine by-products using an in-vitro model of fish digestion

Increasing attention is currently being paid to the protective role of polyphenols in health and oxidative status in fish. For this reason, the potential use of different natural sources of such compounds, like wine by products, is under study. One key step required to gain a better understanding on the biological roles of polyphenols for a given species is to assess the different factors affecting their digestive bioaccessibility, and a great number of such studies is based in the use of in vitro digestion models. In the present study the potential digestive bioavailability of the phenolic compounds present in wine bagasse and lees was evaluated for two fish species showing great differences in their digestive phisyiology: the omnivorous gilthead sea bream (Sparus aurata) and the herbivorous flathead grey mullet (Mugil cephalus). The study was developed using in vitro models adapted to simulate their digestion and a factorial experimental design that simultaneously evaluated the effects of the ingredient used as source of polyphenols, presence or absence of feed matrix, fish species and digestion time. The release of the phenolic compounds was evaluated using ultra-high performance liquid chromatography (UHPLC) coupled to high resolution mass spectrometry (HRMS) detection. Both the presence of feed matrix and the type of wine by-product showed a significant effect on the digestive release of both total and specific types of polyphenols while fish species showed to be significant only for some specific compounds, like eriodyctiol or syringic acid. The time of digestion was not identified as a statistically significant factor in the release of phenolic compounds due to the great variability in the patterns observed that were classified as early, sustained and late. The observed great variations in the patterns of release of different types of phenolic compounds with time suggest an important effect of gut transit rates on the net bioavailability of a given phenolic compound in the live fish. The present study is, to our knowledge, the first one on which an in vitro approach was applied to assess to what extent the possible complexation of wine polyphenols present in wine by-products with either digestive enzymes or components of the feed matrix could limit their bioaccessibility if included in diets of two different fish species.

Alginate and β-lactoglobulin matrix as wall materials for encapsulation of polyphenols to improve efficiency and stability

The present study aimed at developing novel encapsulate materials of calcium-alginate and β-lactoglobulin complex for polyphenols using the jet-flow nozzle vibration method. Encapsulated microbeads were characterized using SEM, FTIR, DSC, and MSI. The encapsulation efficiency of the microbeads varied depending upon the coating material in the range of 74.17–84.87%. Calcium-alginate-β-lactoglobulin microbeads (CABM) exhibited a smooth surface and uniform shape with an average particle size of 1053.73 nm. CABM also showed better thermal and storage stabilities as compared to calcium alginate microbeads. The CABM resulted in excellent target release of polyphenols (84%) in the intestine, which was more than 3-fold the bio-accessibility offered by free polyphenol powder. Further study on individual phenolic acids after simulated in-vitro digestion (SIVD), photo-oxidative and osmotic stress revealed that CABM significantly retained a higher amount of polyphenols and exhibited improved antioxidant capacity after SIVD environment, and may have high industrial application for nutraceutical production.

Effects of Exogenous Caffeic Acid, L-Phenylalanine and NaCl Treatments on Main Active Components Content and In Vitro Digestion of Germinated Tartary Buckwheat

Germination is an effective method for improving the nutritional value of Tartary buckwheat (TB). The effects of exogenous additive treatments (caffeic acid (CA), L-phenylalanine (L-Phe), NaCl) on germination, main active component contents and antioxidant activities before and after in vitro digestion of germinated TB were investigated. Compared with the natural growth group, the T₄ group (CA 17 mg/L, L-Phe 2.7 mmol/L, NaCl 2.7 mmol/L) treatment increased the germination rate (67.50%), sprout length, reducing sugar (53.05%), total flavonoid (18.36%) and total phenolic (20.96%) content, and antioxidant capacity of TB. In addition, exogenous additives treatment induced the consumption of a lot of nutrients during seed germination, resulting in a decrease in the content of soluble protein and soluble sugar. The stress degree of natural germination on seeds was higher than that of low concentrations of exogenous additives, resulting in an increase in malondialdehyde content. In vitro digestion leads to a decrease in phenolics content and antioxidant capacity, which can be alleviated by exogenous treatment. The results showed that treatment with exogenous additives was a good method to increase the nutritional value of germinated TB, which provided a theoretical basis for screening suitable growth conditions for flavonoid enrichment.

Physical Properties, α-Glucosidase Inhibitory Activity, and Digestive Stability of Four Purple Corn Cob Anthocyanin Complexes

In this study, pectin (PC), whey protein isolate (WPI), and chitosan (CS) were combined with purple corn cob anthocyanins (PCCA). Four complexes, PC-PCCA, WPI-PCCA, WPI-PC-PCCA, and CS-PC-PCCA were prepared to evaluate the improvement in the α-glucosidase inhibitory activity and digestive stability of PCCA. The encapsulation efficiency (EE), particle size, physical properties, and mode of action of the synthesized PCCA complexes were evaluated. Among them, CS-PC-PCCA had the highest EE (48.13 ± 2.73%) except for WPI-PC-PCCA; furthermore, it had a medium size (200-300 nm), the lowest hygroscopicity (10.23 ± 0.28%), lowest solubility (10.57 ± 1.26%), and highest zeta potential (28.20 ± 1.14). CS-PC-PCCA was multigranular and irregular in shape; x-ray diffraction showed that it was amorphous; and Fourier transform infrared spectroscopy confirmed that it was joined with PCCA through hydrogen bonds and electrostatic interactions. Compared with PCCA, the four complexes showed a higher α-glucosidase inhibition activity and digestive stability, except for WPI-PC-PCCA. Furthermore, CS-PC-PCCA exhibited the best α-glucosidase inhibition and simulated digestion stability.

Potential Anticancer Activity of Pomegranate (Punica granatum L.) Fruits of Different Color: In Vitro and In Silico Evidence

Pomegranate (PMG; Punica granatum L.) fruits possess a well-balanced nutrient/phytochemical composition, with proven adjuvant benefits in experimental cancer chemotherapy; however, such bioactivity could be affected by PMG's phenogenotype (varietal). Here, the chemical and phytochemical (UPLC-DAD-MS2) composition, antioxidant capacity and anticancer potential [in vitro (MTT assay) and in silico (foodinformatics)] of three PMG fruits of different aryl color [red (cv. Wonderful), pink (cv. Molar de Elche), and white (cv. Indian)] were evaluated. The macro/micronutrient (ascorbic acid, tocols, carotenoids), organic acid (citric/malic), and polyphenol content were changed by PMG's varietal and total antioxidant activity (ABTS, alcoholic > hexane extract) in the order of red > pink > white. However, their in vitro cytotoxicity was the same (IC50 > 200 μg.mL-1) against normal (retinal) and cancer (breast, lung, colorectal) cell lines. Sixteen major phytochemicals were tentatively identified, four of them with a high GI absorption/bioavailability score [Ellagic (pink), vanillic (red), gallic (white) acids, D-(+)-catechin (white)] and three of them with multiple molecular targets [Ellagic (52) > vanillic (32) > gallic (23)] associated with anticancer (at initiation and promotion stages) activity. The anticancer potential of the PMG fruit is phenogenotype-specific, although it could be more effective in nutraceutical formulations (concentrates).

Dietary polyglycosylated anthocyanins, the smart option? A comprehensive review on their health benefits and technological applications

Over the years, anthocyanins have emerged as one of the most enthralling groups of natural phenolic compounds and more than 700 distinct structures have already been identified, illustrating the exceptional variety spread in nature. The interest raised around anthocyanins goes way beyond their visually appealing colors and their acknowledged structural and biological properties have fueled intensive research toward their application in different contexts. However, the high susceptibility of monoglycosylated anthocyanins to degradation under certain external conditions might compromise their application. In that regard, polyglycosylated anthocyanins (PGA) might offer an alternative to overcome this issue, owing to their peculiar structure and consequent less predisposition to degradation. The most recent scientific and technological findings concerning PGA and their food sources are thoroughly described and discussed in this comprehensive review. Different issues, including their physical-chemical characteristics, consumption, bioavailability, and biological relevance in the context of different pathologies, are covered in detail, along with the most relevant prospective technological applications. Due to their complex structure and acyl groups, most of the PGA exhibit an overall higher stability than the monoglycosylated ones. Their versatility allows them to act in a wide range of pathologies, either by acting directly in molecular pathways or by modulating the disease environment attributing an added value to their food sources. Their recent usage for technological applications has also been particularly successful in different industry fields including food and smart packaging or in solar energy production systems. Altogether, this review aims to put into perspective the current state and future research on PGA and their food sources.

The Effect of In Vitro Gastrointestinal Digestion on the Antioxidants, Antioxidant Activity, and Hypolipidemic Activity of Green Jujube Vinegar

Healthy fruit vinegar has been extensively favored in China in recent years. As a new type of fruit vinegar developed by our laboratory, green jujube vinegar has the characteristics of good taste and rich nutrition. To study the effect of in vitro gastrointestinal digestion on the antioxidant and hypolipidemic activity of green jujube vinegar, so as to provide basic data for research and the development of healthy food antioxidants, including the total phenolic content (TPC), total flavonoid content (TFC), total acid content, and volatile acid content, were measured. The antioxidant activity was measured by using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) free radical scavenging methods and the ferric reducing antioxidant power assay (FRAP), and the hypolipidemic activity was measured by cholesterol adsorption and the sodium cholate adsorption capacities. The results show that gastric digestion significantly (p < 0.05) decreased the TPC, TFC, total acid content, and volatile acid content, for which the highest reductions were up to 54.17%, 72%, 88.83% and 82.35%, respectively. During intestinal digestion, the TFC remained at a high level and unchanged, and the TFC and volatile acid content significantly (p < 0.05) decreased by 72.66% and 89.05%, respectively. The volatile acid content did not significantly (p > 0.05) change within 2 h. The ABTS free radical scavenging ability and the reducing power free radical scavenging rate were correlated with the TPC, TFC, and total acid contents, and the DPPH free radical scavenging ability and cholesterol adsorption capacity were not. These findings suggest that green jujube vinegar can be a potential functional food for people’s use.

Insights into gut microbiota metabolism of dietary lipids: the case of linoleic acid

It has been recognized that, next to dietary fibre and proteins, gut microbiota can metabolize lipids producing bioactive metabolites. However, the metabolism of dietary lipids by human gut microbiota has been poorly explored so far. This study aimed to examine the change in lipids, particularly linoleic acid (LA), induced by the chemical form of lipids and the presence of the plant matrix. Short-chain fatty acid (SCFA) production was monitored to get an insight into microbial activity. Free LA, glyceryl trilinoleate and soybean oil as well as digested intact (DS) and broken (BS) soybean cells were subjected to in vitro fermentation using human faecal inoculums. Confocal microscopy was used to visualize the soybean cell integrity. Three LA metabolites, including two conjugated fatty acids (CLAs, 9z,11e and 9e,11e) and 12hydroxy, 9z C18:1, were identified and monitored. Free LA addition improved the LA metabolite production but reduced SCFA concentrations compared to trilinoleate and soybean oil. Breaking cell integrity had impacts on CLA, hydroxy C18:1 and SCFA production and free fatty acid release within the first 24 h of fermentation, but this effect vanished with time. In contrast, soybean oil only increased free LA release and hydroxy C18:1 production. The content of several FAs decreased during fermentation suggesting a substantial conversion in microbial metabolites. Besides, LA metabolites were also identified in the fermentation pellets suggesting the incorporation of microbial FA metabolites into bacterial cells. This study expands our understanding of microbial metabolism of dietary lipids with a special emphasis on the role of food- and diet-related factors.

Tamarillo Polyphenols Encapsulated-Cubosome: Formation, Characterization, Stability during Digestion and Application in Yoghurt

Tamarillo extract is a good source of phenolic and anthocyanin compounds which are well-known for beneficial antioxidant activity, but their bioactivity maybe lost during digestion. In this study, promising prospects of tamarillo polyphenols encapsulated in cubosome nanoparticles prepared via a top-down method were explored. The prepared nanocarriers were examined for their morphology, entrapment efficiency, particle size and stability during in vitro digestion as well as potential fortification of yoghurt. Tamarillo polyphenol-loaded cubosomes showed cubic shape with a mean particle size of 322.4 ± 7.27 nm and the entrapment efficiency for most polyphenols was over 50%. The encapsulated polyphenols showed high stability during the gastric phase of in vitro digestion and were almost completely, but slowly released in the intestinal phase. Addition of encapsulated tamarillo polyphenols to yoghurt (5, 10 and 15 wt% through pre- and post-fermentation) improved the physicochemical and potential nutritional properties (polyphenols concentration, TPC) as well as antioxidant activity. The encapsulation of tamarillo polyphenols protected against pH changes and enzymatic digestion and facilitated a targeted delivery and slow release of the encapsulated compounds to the intestine. Overall, the cubosomal delivery system demonstrated the potential for encapsulation of polyphenols from tamarillo for value-added food product development with yoghurt as the vehicle.

Anti-Inflammatory Properties, Bioaccessibility and Intestinal Absorption of Sea Fennel (Crithmum maritimum) Extract Encapsulated in Soy Phosphatidylcholine Liposomes

A sea fennel (Crithmum maritimum) aqueous extract was prepared and loaded into soybean phosphatidylcholine liposomes. Both the free extract (FE), and the empty (L) and loaded (L-FE) liposomes were shown to be non-cytotoxic to THP-1 and Caco-2 cells. The anti-inflammatory effect was tested on THP-1 cells differentiated into macrophages. FE showed anti-inflammatory activity, revealed by the induced secretion of IL-10 cytokines in macrophages that were subsequently stimulated with LPS. Also, a decrease in TNF-α production by L was observed, evidencing that liposomes reduced the pro-inflammatory mediators' secretion. The liposomes (L) showed protective anti-inflammatory activity and also were able to downregulate the inflammation. Furthermore, L-FE were also found to downregulate the inflammation response, as they were able to decrease TNF-α secretion in macrophages previously exposed to LPS. The simulated in vitro gastrointestinal digestion (GID) of FE diminished the chlorogenic acid content (the main polyphenolic compound of the extract) by 40%, while in L-FE, the amount of this phenolic compound increased with respect to the undigested liposomes. The amount of bioaccessible chlorogenic, however, was similar for FE and L-FE. The percentage of chlorogenic acid absorbed through a Caco-2 cell monolayer after 3 h of incubation, was significantly similar for the extract and the liposomes (~1.5%), without finding significant differences once the extract and liposomes were digested.

Co-Ingestion of Natal Plums (Carissa macrocarpa) and Marula Nuts (Sclerocarya birrea) in a Snack Bar and Its Effect on Phenolic Compounds and Bioactivities

This study investigated the effect of co-ingesting Natal plums (Carissa macrocarpa) and Marula nuts (Sclerocarya birrea) on the bioaccessibility and uptake of anthocyanins, antioxidant capacity, and the ability to inhibit α-glucosidase. A Natal plum-Marula nut bar was made by mixing the raw nuts and the fruit pulp in a ratio 1:1 (v/v). The cyanidin-3-O-sambubioside (Cy-3-Sa) and cyanidin-3-O-glucoside content (Cy-3-G) were quantified using the ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). Inclusion of Natal plum in the Marula nut bar increased the Cy-3-Sa, Cy-3-G content, antioxidants capacity and α-glucosidase inhibition compared to ingesting Marula nut separately at the internal phase. Adding Natal plum to the Marula nut bar increased bioaccessibility of Cy-3-Sa, Cy-3-G, quercetin, coumaric acid, syringic acid and ferulic acid to 80.2% and 71.9%, 98.7%, 95.2%, 51.9% and 89.3%, respectively, compared to ingesting the Natal plum fruit or nut separately.

Influence of Phenolic-Food Matrix Interactions on In Vitro Bioaccessibility of Selected Phenolic Compounds and Nutrients Digestibility in Fortified White Bean Paste

This model study aimed to evaluate the effect of phenolic–food matrix interactions on the in vitro bioaccessibility and antioxidant activity of selected phenolic compounds (gallic acid, ferulic acid, chlorogenic acid, quercetin, apigenin, and catechin) as well as protein and starch digestibility in fortified white bean paste. The magnitude of food matrix effects on phenolics bioaccessibility and antioxidant activity was estimated based on “predicted values” and “combination indexes”. Furthermore, the protein–phenolics interactions were investigated using electrophoretic and chromatographic techniques. The results demonstrated phenolic–food matrix interactions, in most cases, negatively affected the in vitro bioaccessibility and antioxidant activity of phenolic compounds as well as nutrient digestibility. The lowest in vitro bioaccessibility of phenolic compounds in fortified paste was found for quercetin (45.4%). The most negative impact on the total starch digestibility and relative digestibility of proteins was observed for catechin–digestibility lower by 14.8%, and 21.3% (compared with control), respectively. The observed phenolic–food matrix interactions were strictly dependent on the applied phenolic compound, which indicates the complex nature of interactions and individual affinity of phenolic compounds to food matrix components. In conclusion, phenolic–food matrix interactions are an important factor affecting the nutraceutical and nutritional potential of fortified products.

Potential micro-/nano-encapsulation systems for improving stability and bioavailability of anthocyanins: An updated review

Anthocyanins (ACNs) are notable hydrophilic compounds that belong to the flavonoid family, which are available in plants. They have excellent antioxidants, anti-obesity, anti-diabetic, anti-inflammatory, anticancer activity, and so on. Furthermore, ACNs can be used as a natural dye in the food industry (food colorant). On the other hand, the stability of ACNs can be affected by processing and storage conditions, for example, pH, temperature, light, oxygen, enzymes, and so on. These factors further reduce the bioavailability (BA) and biological efficacy of ACNs, as well as limit ACNs application in both food and pharmaceutics field. The stability and BA of ACNs can be improved via loading them in encapsulation systems including nanoemulsions, liposomes, niosomes, biopolymer-based nanoparticles, nanogel, complex coacervates, and tocosomes. Among all systems, biopolymer-based nanoparticles, nanohydrogels, and complex coacervates are comparatively suitable for improving the stability and BA of ACNs. These three systems have excellent functional properties such as high encapsulation efficiency and well-stable against unfavorable conditions. Furthermore, these carrier systems can be used for coating of other encapsulation systems (such as liposome). Additionally, tocosomes are a new system that can be used for encapsulating ACNs. ACNs-loaded encapsulation systems can improve the stability and BA of ACNs. However, further studies regarding stability, BA, and in vivo work of ACNs-loaded micro/nano-encapsulation systems could shed a light to evaluate the therapeutic efficacy including physicochemical stability, target mechanisms, cellular internalization, and release kinetics.

Effect of In Vitro Digestion on the Antioxidant Compounds and Antioxidant Capacity of 12 Plum (Spondias purpurea L.) Ecotypes

Spondias purpurea L. plum is a source of antioxidant compounds. Nevertheless, once they are consumed and go through the digestive system, these compounds may undergo changes that modify their bioaccessibility. This study aimed to evaluate the effect of in vitro gastrointestinal digestion on the total content of carotenoids (TCC), ascorbic acid (AA), phenolic compounds (TPC), flavonoids (TFC), anthocyanins (TAC), and antioxidant capacity (ABTS, DPPH) of 12 plum Spondias purpurea L. ecotypes. The plum samples were subjected to the InfoGest in vitro digestion model. TCC, AA, TPC, TFC, TAC, ABTS, and DPPH were significantly different (p ≤ 0.05) in each in vitro digestion stage. The gastric stage released the highest content of AA (64.04–78.66%) and TAC (128.45–280.50%), whereas the intestinal stage released the highest content of TCC (11.31–34.20%), TPC (68.61–95.36%), and TFC (72.76–95.57%). Carotenoids were not identified in the gastric stage whilst anthocyanins were lost at the end of the intestinal digestion. At the gastric stage, AA presented a positive and high correlation with ABTS (r: 0.83) and DPPH (r: 0.84), while, in the intestinal stage, TPC and TFC presented positive and high correlation with ABTS (r ≥ 0.8) and DPPH (r ≥ 0.8), respectively.

Antioxidant Activity and Healthy Benefits of Natural Pigments in Fruits: A Review

Natural pigments, including carotenoids, flavonoids and anthocyanidins, determine the attractive color of fruits. These natural pigments are essential secondary metabolites, which play multiple roles in the whole life cycle of plants and are characterized by powerful antioxidant activity. After decades of research and development, multiple benefits of these natural pigments to human health have been explored and recognized and have shown bright application prospects in food, medicine, cosmetics and other industries. In this paper, the research progress of natural fruit pigments in recent years was reviewed, including the structural characteristics and classification, distribution in fruits and analysis methods, biosynthetic process, antioxidant capacity and mechanism, bioaccessibility and bioavailability, and health benefits. Overall, this paper summarizes the recent advances in antioxidant activity and other biological functions of natural fruit pigments, which aims to provide guidance for future research.

Current status of the gastrointestinal digestion effects on honey: A comprehensive review

In the past five years, more than 8000 scientific reports have been published on honey composition and its potential bioactivity as a source of pro-health components. However, the potential effectiveness of nutrients and other compounds in the human body is greatly influenced by the individual digestion conditions. Consequently, changes in the structure of honey components and their interactions with other constituents are expected and they may affect the bioaccessibility, the bioavailability, and further physiological functions of honey nutrients and bioactives. In this context, in addition to present key physiological characteristics for each step of the human digestion and their simulation aspects, this review also summarizes and discusses available data regarding the effect of the digestion (in vitro and in vivo) on honey compounds. Additionally, we consider the influence of the digestion on biological activities described for the compounds in the honey.

The Effects of Bioactive Compounds from Blueberry and Blackcurrant Powder on Oat Bran Pastes: Enhancing In Vitro Antioxidant Activity and Reducing Reactive Oxygen Species in Lipopolysaccharide-Stimulated Raw264.7 Macrophages

In this study, blueberry and blackcurrant powder were chosen as the phenolic-rich enrichments for oat bran. A Rapid Visco Analyser was used to form blueberry and blackcurrant enriched oat pastes. An in vitro digestion process evaluated the changes of phenolic compounds and the in vitro antioxidant potential of extracts of pastes. The anthocyanidin profiles in the extracts were characterised by the pH differential method. The results showed that blueberry and blackcurrant powder significantly increased the content of phenolic compounds and the in vitro antioxidant capacity of pastes, while the total flavonoid content decreased after digestion compared to the undigested samples. Strong correlations between these bioactive compounds and antioxidant values were observed. Lipopolysaccharide-stimulated RAW264.7 macrophages were used to investigate the intracellular antioxidant activity of the extracts from the digested oat bran paste with 25% enrichment of blueberry or blackcurrant powder. The results indicated that the extracts of digested pastes prevented the macrophages from experiencing lipopolysaccharide (LPS)-stimulated intracellular reactive oxygen species accumulation, mainly by the Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid 2-related factor 2 (Nrf2) signalling pathway. These findings suggest that the bioactive ingredients from blueberry and blackcurrant powder enhanced the in vitro and intracellular antioxidant capacity of oat bran pastes, and these enriched pastes have the potential to be utilised in the development of the functional foods.

The recovery, catabolism and potential bioactivity of polyphenols from carrot subjected to in vitro simulated digestion and colonic fermentation

Carrot powder digestion was researched utilizing an in vitro standardized static model associated with an in vitro colonic fermentation method to analyze the recovery, catabolism, and potential bioactivity of polyphenols from carrot. Twenty-seven polyphenols and their metabolites (hydroxybenzoic acids, hydroxycinnamic acids and its derivatives, etc.) were identified in samples before and after digestion/colonic fermentation, and the possible colonic pathways for major polyphenols were proposed. Polyphenols had low recovery during different phases of in vitro digestion (oral: -51.4%; gastric: -38%; intestinal: -35.3%, respectively). However, the concentration of polyphenols (p-hydroxybenzoic acid, gallic acid and protocatechuic acid) increased significantly after colonic fermentation for 12 h with 1391.7% recovery, then significantly declined after 48 h. Meanwhile, the released and catabolized polyphenols showed antioxidant activity and α-glucosidase inhibitory capacity (IC₅₀ = 9.91 μg GAE/mL). The microbe community structure was regulated by fecal fermented carrot powder through improving relative abundance (RA) of beneficial microbiota and suppressed RA of various harmful bacteria. This work indicated that polyphenols from carrot potentially play a role in gastrointestinal and colonic health.

Changes in bioactive compounds and antioxidant activity of plant-based foods by gastrointestinal digestion: a review

Phenolic compounds, omnipresent in plants, are a crucial part of the human diet and are of considerable interest due to their antioxidant properties and other potential beneficial health effects, for instance, antidiabetic, antihypertensive, anti-inflammatory, and anticancer properties. The consumption of a variety of plant-based foods containing various phenolic compounds has increased due to published scientific verification of several health benefits. The release of phenolic compounds and change in their bioactivities examined through in vitro simulated gastrointestinal digestion could provide information on the biological potency of bioactive components, which will allow us to elucidate their metabolic pathways and bioactivities at target sites. This review reports on the recent research results focused on changes during the gastro and/or intestinal phase. The effect of digestive enzymes and digestive pH conditions during simulated digestion accounted for the variations in bioaccessibility and bioavailability of phenolic antioxidants as well as the corresponding antioxidant activities were also summarized and presented in the review.

Matrix- and Technology-Dependent Stability and Bioaccessibility of Strawberry Anthocyanins during Storage

Anthocyanins are often associated with health benefits. They readily degrade during processing and storage but are also dependent on the matrix conditions. This study investigated how strawberry anthocyanins are affected by preservation technologies and a relatively protein-rich kale juice addition during storage. A strawberry–kale mix was compared to a strawberry–water mix (1:2 wt; pH 4), untreated, thermally, pulsed electric fields (PEF) and high-pressure processing (HPP) treated, and evaluated for anthocyanin stability and bioaccessibility during refrigerated storage. The degradation of strawberry anthocyanins during storage followed first-order kinetics and was dependent on the juice system, preservation technology and anthocyanin structure. Generally, the degradation rate was higher for the strawberry–kale mix compared to the strawberry–water mix. The untreated sample showed the highest degradation rate, followed by HPP, PEF and, then thermal. The relative anthocyanin bioaccessibility after gastric digestion was 10% higher for the thermally and PEF treated samples. Anthocyanin bioaccessibility after intestinal digestion was low due to instability at a neutral pH, especially for the strawberry–kale mix, and after thermal treatment. The storage period did not influence the relative bioaccessibility; yet, the absolute content of bioaccessible anthocyanins was decreased after storage. This research further presents that processing and formulation strongly affect the stability and bioaccessibility of anthocyanins during storage.

Effects of Anthocyanins in Composite Meals on Cardiometabolic Outcomes-A Systematic Review of Randomized Controlled Feeding Trials

Accumulating epidemiological evidence suggests that anthocyanin intake is associated with reduced risks of cardiometabolic disorders, highlighting the importance of incorporating the phytochemical in our diets. Numerous food-based intervention studies have examined, in controlled meal settings, the role of anthocyanin on cardiometabolic health; but their effects have not been systematically summarized. This study aims to systematically review and summarize the effects of anthocyanin consumption with composite meals on cardiometabolic health from randomized controlled feeding trials. A systematic literature search for relevant human nutritional intervention studies was performed using PubMed, Embase, Cochrane Library, CINAHL Plus with Full Text, and Scopus databases. The Cochrane Risk of Bias tool was used to assess the study quality. Eighteen articles involving 371 participants were included in this review. Consistent improvements from anthocyanin intake were found in glycemic, gastric inhibitory peptide (GIP), interleukin-6 (IL-6), and oxygen radical absorbance capacity (ORAC) responses. Anthocyanin intake did not significantly affect other markers of energy metabolism, vascular functions, oxidative stress and antioxidant status, as well as inflammatory responses. Inconsistencies in successful outcomes between epidemiological studies and included interventions were largely attributed to matrix effects, which may impede the bioaccessibility of anthocyanins and consequently, limiting its health benefits when co-delivered with some foods.

The effect of in vitro digestion, food matrix, and hydrothermal treatment on the potential bioaccessibility of selected phenolic compounds

The effects of in vitro digestion, hydrothermal treatment, and food matrices (wheat flour, durum wheat flour, wholemeal wheat flour, corn flour, rice flour) on the bioaccessibility of phenolic compounds (gallic acid, p-coumaric acid, ferulic acid, chlorogenic acid, catechin) were investigated. The influence of experimental factors and their combinations was estimated based on the "Dose Correction Index" (DCI) concept. Generally, the applied conditions had a negative effect on the bioaccessibility of polyphenols; however, the effect depended on the type of compound and food matrix, which was reflected in different DCI values. A less unfavorable effect on the bioaccessibility was exerted by the rice flour (the lowest DCI values), but the most negative impact was found in the case of the wholemeal wheat flour. The DCI concept provides basic knowledge of the magnitude of factors affecting the bioaccessibility of polyphenols, which can be useful for designing fortified products with desirable bioactivity.