Various steaming durations alter digestion, absorption, and fermentation by human gut microbiota outcomes of Polygonatum cyrtonema Hua polysaccharides.

Introduction: Different steaming durations dramatically alter the structure of Polygonatum cyrtonema polysaccharides (PCPs). This study aimed to compare characteristics of digestion, absorption, and fermentation by gut microbiota across four representative PCPs from different steaming durations (0, 4, 8, and 12 h), each with unique molecular weights and monosaccharide profiles. Methods: Chemical composition of the four PCPs was analyzed. Digestibility was evaluated using an in vitro saliva-gastrointestinal digestion model. Absorption characteristics were assessed with a Caco-2 monolayer model, and impacts on gut microbiota composition and short chain fatty acid (SCFA) levels were analyzed using in vitro fermentation with human gut microbiota. Results: Longer steaming durations altered the chemical profiles of PCPs, reducing carbohydrate content (84.87-49.58%) and increasing levels of uronic acid (13.99-19.61%), protein (1.07-5.43%), and polyphenols (0.05-2.75%). Four PCPs were unaffected by saliva digestion but showed enhanced gastrointestinal digestibility, with reducing sugar content rising from 4.06% (P0) to 38.5% (P12). The four PCPs showed varying absorption characteristics, with P0 having the highest permeability coefficient value of 9.59 × 10-8 cm/s. However, all PCPs exhibited poor permeability, favoring gut microbiota fermentation. The four PCPs altered gut microbiota composition and elevated SCFA production, but levels declined progressively with longer steaming durations. All PCPs significantly increased the abundance of Bacteroidota, Firmicutes, and Actinobacteriota, making them the dominant bacterial phyla. Additionally, all PCPs significantly increased the abundance of Bifidobacterium, Prevotella, and Faecalibacterium compared to the control group, which, along with Bacteroides, became the dominant microbiota. Increasing the steaming duration led to a reduction in Prevotella levels, with PCPs from raw rhizomes showing the highest relative abundance at 24.90%. PCPs from moderately steamed rhizomes (4 h) led to a significant rise in Faecalibacterium (7.73%) among four PCPs. P8 and P12, derived from extensively steamed rhizomes (≥8 h), exhibited similar gut microbiota compositions, with significantly higher relative abundances of Bacteroides (20.23-20.30%) and Bifidobacterium (21.05-21.51%) compared to P0 and P4. Discussion: This research highlights the importance of adjusting steaming durations to maximize the probiotic potential of P. cyrtonema polysaccharides, enhancing their effectiveness in modulating gut microbiota and SCFA levels.

In Vitro Digestion of Vacuum-Impregnated Yam Bean Snacks: Pediococcus acidilactici Viability and Mango Seed Polyphenol Bioaccessibility.

This study investigates the in vitro digestion of vacuum-impregnated yam bean snacks enriched with Pediococcus acidilactici and mango seed polyphenols, focusing on bacterial survival and polyphenol bioaccessibility. The snacks were prepared by vacuum impregnation (VI) with solutions containing either mango seed extract, P. acidilactici, or a combination of both, followed by dehydration. The antimicrobial activity of the treatments was assessed against pathogens, revealing limited effectiveness, likely due to insufficient concentrations of mango seed extract and the intrinsic resistance of the bacteria. VI of mango seed extract improved the total soluble phenols (TSP) content up to 400% and maintained the initial probiotic concentration (106 cell/mL). In vitro digestion was performed to simulate gastrointestinal conditions, measuring the stability of TSP and the survival of P. acidilactici. The results indicated that the viability of P. acidilactici fluctuated throughout the digestion process (106 to 104 log UFC/g), the polyphenols showed varying degrees of bioaccessibility (11 to 30%), and the TSP content in the intestinal fraction ranged from 1.95 to 6.54 mg GAE/g. The study highlights the potential of VI for incorporating functional components into plant-based snacks, though further optimization is necessary to enhance the stability of P. acidilactici and the effectiveness of the bioactive ingredients.

In vitro digestion and fecal fermentation behaviors of exopolysaccharide from Morchella esculenta and its impacts on hypoglycemic activity via PI3K/Akt signaling and gut microbiota modulation.

This study aimed to evaluate the effects of gastrointestinal digestion on the physicochemical properties and hypoglycemic activity of extracellular polysaccharides from Morchella esculenta (MEPS). The results showed that the MEPS digestibility was 22.57 % after saliva-gastrointestinal digestion and only partial degradation had occurred. Contrarily, after 48 h of fecal fermentation, its molecular weight and molar ratios of the monosaccharide composition varied significantly due to being utilized by human gut microbiota, and the final fermentation rate was 76.89 %. Furthermore, the MEPS-I, the final product of saliva-gastrointestinal digestion still retained significant hypoglycemic activity, it alleviated insulin resistance and increased the IR cells glucose consumption by activating PI3K/AKT signaling pathway. MEPS-I treatment reduced the proportion of Firmicutes to Bacteroidetes, and the relative abundance of beneficial bacteria that enhanced insulin sensitivity and glucose uptake was promoted. This research can provide a theoretical basis for the further development of Morchella esculenta as a health functional food.

Optimization of extraction process of polysaccharide from Phylloporia fontanesiae and its simulated digestion in vitro.

In this study, Phylloporia fontanesiae polysaccharide was successfully isolated through a sequential water extraction and alcohol precipitation process. Utilizing the Box-Behnken design, the extraction process was optimized based on single-factor experiments, considering variables such as the material-to-liquid ratio, extraction temperature, extraction time, and the number of extractions. The polysaccharide composition of P. fontanesiae is predominantly composed of mannose, glucuronic acid, glucose, and galactose, with a molar mass ratio of 4.31:4.10:36.83:1, along with minor amounts of aminoglucose and fucose. The polysaccharide fraction of P. fontanesiae comprises two distinct components, possessing relative molecular masses of 8.85 kDa and 134.03 kDa. Notably, the polysaccharide exhibited significant antioxidant activity. After undergoing simulated gastrointestinal digestion, no significant changes were observed in its antioxidant activity, molecular weight, or monosaccharide composition. This study not only enhanced the extraction efficiency of P. fontanesiae polysaccharide but also provided valuable insights into its composition, structure, and digestion characteristics. PRACTICAL APPLICATION: The optimum extraction process, stability, and antioxidant activity of Phylloporia fontanesiae polysaccharide during simulated digestion of gastrointestinal tract were studied. The results provide a theoretical basis for the development and application of this polysaccharide in the field of food and health products.

Improvement of egg yolk powder properties through ultrasound coupled sodium sulfite pretreatment assisted enzymatic hydrolysis and underlying mechanism.

Egg yolk is an excellent protein source for the production of bioactive peptides. However, the recent method need to remove lipid first which involves wastage and pollution of organic reagents. Therefore, the process of directly using oily yolk powder to prepare egg yolk peptides has attracted much attention. This study developed a one-step process to simultaneously extract oil and hydrolyze proteins based on an ultrasound coupled sodium sulfite pretreatment (UCSSP) assisted enzymatic hydrolysis for egg yolk powder. Results showed that UCSSP increased the oil extraction rate from zero to 75 % with 59.35 g/L of soluble protein and 33.99 g/L of peptide. Further analysis of the underlying mechanism demonstrated that ultrasound pre-treatment could change the secondary structure of EYP while sodium sulfite pre-treatment softened the protein and induced more hydrophobic groups exposed, thus inducing more lipoprotein released for hydrolysis. In addition, the proportion of peptides ranging from 180 Da to 3000 Da in the UCSSP group increased from 31.19 % before to 79.74 %, which was 31.27 % and 6.16 % higher than that of UP and SP. Furthermore, the obtained peptides showed obvious activities in uric acid-lowering, anti-obesity and antioxidant with 56.24 % inhibition in XOD activity and close antioxidant activity to vitamin C, implying it a potential health product.

Loading bioactive peptides within different nanocarriers to enhance their functionality and bioavailability; in vitro and in vivo studies.

A hydrolyzed protein is a blend of peptides and amino acids which is the result of hydrolysis by enzymes, acids or alkalis. The Bioactive Peptides (BPs) show important biological roles including antioxidant, antimicrobial, anti-diabetic, anti-cancer, and anti-hypertensive effects, as well as positive effects on the immune, nervous, and digestive systems. Despite the benefits of BPs, challenges such as undesired organoleptic properties, solubility profile, chemical instability, and low bioavailability limit their use in functional food formulations and dietary supplements. Nanocarriers have emerged as a promising solution for overcoming these challenges by improving the stability, solubility, resistance to gastric digestion, and bioavailability, allowing for the targeted and controlled delivery, and reduction or masking of the undesirable flavor of BPs. This study reviews the recent scientific accomplishments concerning the loading of BPs into various nanocarriers including lipid, carbohydrate and protein based-nanocarriers. A special emphasis is given to their application in food formulations in accordance to the challenges associated with their use.

Targeted and non-targeted metabolic characteristics of 6,7-dihydroxy-2,4- dimethoxyphenanthrene during simulated gastrointestinal digestion.

6,7-dihydroxy-2,4-dimethoxyphenanthrene (PC4), isolated and identified from Chinese yam, was one of the important characteristic active ingredients. The present study established simulated gastrointestinal digestion and caco-2 intestinal epithelial models to investigate the digestive and metabolic characteristics of PC4. The results indicated that PC4 was mainly digested and metabolized in the intestine, with a digestion rate of 94 %, producing active characteristic metabolites including 2,6-dimethoxy-4-phenanthrenol (MC1) and 1-methoxyphenanthrene (MC2). Molecular docking indicated that the COX-2 enzyme inhibitory activity of MC1 might be superior to that of the prototype PC4. During 24 h co-incubation of PC4 with caco-2 monolayer epithelial, the signal pathway related to lipid decomposition was up-regulated within 0-12 h, while the diabetes complications AGE-RAGE was inhibited just in 0-6 h period significantly. The research database provided scientific basis for the digestion and metabolism of PC4, and laid theoretical foundation for the scientific development of Chinese yam functional foods.

Unveiling fucoxanthin's fate: In vitro gastrointestinal digestion effects on bioaccessibility, antioxidant potential, colour changes, and metabolite profiles.

Limited knowledge of fucoxanthin's changes during digestion necessitates comprehensive investigation to ensure its efficacy as a functional ingredient. This study assessed the effects of digestion on fucoxanthin's bioaccessibility, antioxidant activity, colour changes, and metabolite formation through in vitro gastrointestinal digestion. Results indicated the highest bioaccessibility during gastric digestion (0.03 ± 0.00 mg/mL), followed by intestinal and mouth with 0.012 ± 0.00 and 0.011 ± 0.13 mg/mL, respectively. Antioxidant activity was the highest at the gastric stage, with significant activity persisting post-digestion (P < 0.05). Colour changes were significant, with total colour differences (∆E*) of 2.40, 2.86, and 2.76 at the mouth, gastric, and intestinal stages, respectively. LC-MS/MS-based metabolomics analysis revealed 15 key metabolites, with carboxylic acids as major metabolites during gastric and intestinal stages. Pearson correlation analysis demonstrated a significant correlation between identified metabolites with bioaccessibility, antioxidant activity, and colour changes, underscoring fucoxanthin's potential as a promising functional food ingredient.

Structural changes and in vitro bioaccessibility of CPP-febisgly complexes: Dependence on iron load.

The effect of casein phosphopeptides (CPP) and ferrous bisglycinate (FebisGly) at different ratios (1:20, 1:10, and 1:5 w/w) on iron supplementation was investigated. The in vitro bioaccessibility, structural changes, antioxidant activity, and the effect of absorption inhibitors were also explored. The results demonstrated that CPP enhanced the bioaccessibility of FebisGly by 68.72 % ± 0.18 % and increased the ß-sheet content from 21.60 % ± 0.23 % to 67.92 % ± 0.12 %, forming a stable secondary structure. The particle size distribution (PSD) and rheological analyses indicated that CPP significantly contributed to the formation of chelated irons, resulting in a uniform PSD and enhanced viscoelasticity. Moreover, it prolonged the gastric emptying time, reducing gastric irritation further. The carboxyl and amino groups in the CPP molecules participated in chelation reaction, improved the antioxidant activity, and competed with phytic acid, tannic acid, and cellulose for iron. Overall, these results laid a foundation for developing novel iron supplementation strategies.

Millet Bran Dietary Fibers Modified by Heating and Enzymolysis Combined with Carboxymethylation, Acetylation, or Crosslinking: Influences on Properties of Heat-Induced Egg White Protein Gel.

Applications of millet bran dietary fiber (MBDF) in the food industry are limited by its poor hydration properties. Herein, MBDF was modified by heating, xylanase and cellulase treatment separately combined with carboxymethylation, acetylation, and phosphate crosslinking, and the effects of the modified MBDFs on heat-induced egg white protein gel (H-EWG) were studied. The results showed that three composite modifications, especially heating and dual enzymolysis combined with carboxymethylation, increased the surface area, soluble fiber content, and hydration properties of MBDF (p < 0.05). MBDF and the modified MBDFs all made the microstructure of H-EWG denser and decreased its α-helix content. Three composite modifications, especially heating and dual enzymolysis combined with carboxymethylation, enhanced the improving effect of MBDF on the WRA (from 24.89 to 35.53 g/g), pH, hardness (from 139.93 to 323.20 g), chewiness, and gumminess of H-EWPG, and enhanced the gastric stability at 3-5 g/100 g. MBDFs modified with heating and dual enzymolysis combined with acetylation or crosslinking were more effective in increasing the antioxidant activity of the gastrointestinal hydrolysates of H-EWG than MBDF (p < 0.05). Overall, heating, xylanase and cellulase treatment separately combined with carboxymethylation, acetylation and crosslinking can enhance the hydration properties and the improving effect of millet bran fibers on H-EWG properties.

Impact of Alcalase Hydrolysis and Simulated Gastrointestinal Digestion on the Release of Bioactive Peptides from Erythrina edulis (Chachafruto) Proteins.

Amidst increasing awareness of diet-health relationships, plant-derived bioactive peptides are recognized for their dual nutritional and health benefits. This study investigates bioactive peptides released after Alcalase hydrolysis of protein from chachafruto (Erythrina edulis), a nutrient-rich South American leguminous plant, focusing on their behavior during simulated gastrointestinal digestion. Evaluating their ability to scavenge radicals, mitigate oxidative stress, and influence immune response biomarkers, this study underscores the importance of understanding peptide interactions in digestion. The greatest contribution to the antioxidant activity was exerted by the low molecular weight peptides with ORAC values for the <3 kDa fraction of HES, GD-HES, and GID-HES of 0.74 ± 0.03, 0.72 ± 0.004, and 0.56 ± 0.01 (µmol TE/mg protein, respectively). GD-HES and GID-HES exhibited immunomodulatory effects, promoting the release of NO up to 18.52 and 8.58 µM, respectively. The findings of this study highlighted the potential of chachafruto bioactive peptides in functional foods and nutraceuticals, supporting human health through dietary interventions.

Fermented blend from sunflower seed press-cake and bovine sweet whey: Protein breakdown during in vitro gastrointestinal digestion.

Sustainable food production implements circular economic system, valuing side streams and minimizing waste. This study was aimed to develop a new food by fermenting a blend of dehulled sunflower seed protein powder (SSPP) and reconstituted bovine sweet whey powder (RSWP). Blends were inoculated with Lactococcus lactis B12 alone or in association with Saccharomyces cerevisiae L12, and fermentation proceeded until reaching pH 4.8. After in vitro static gastrointestinal digestion, RSWP and SSPP proteins were highly proteolyzed and the soluble nitrogen content was 69-71% of total nitrogen. In digests, 42-75 unique peptides were identified, and most of them weighed 500-1000 Da. Free amino acids accounted for 202-228 mg/g protein in digests. Few bioactive peptides derived from RSWP were identified. These findings demonstrated strong degradability of RSWP and SSPP proteins during digestion and shed light on nutritional properties exploitable for food applications of the developed fermented blend.

In vitro digestion and fermentation of the whole goji berry: Bioactive ingredients change and impacts on human gut microbiota.

Goji berry (Lycium barbarum L.) is a nutrient-rich fruit and has received enormous interest for its health benefits. The beneficial effects of goji berry are linked to the absorption of bioactive compounds within the gastrointestinal digestion process and colon fermentation. Nonetheless, how certain bioactive compounds were released, and metabolism changed of the consumption of whole goji berries were still unclear. Therefore, the present study aimed to evaluate the digestion characteristics of key bioactive compounds in whole goji berries with an in vitro digestion model, and the effects of whole goji berries on the structure of gut microbiota were also investigated. Results showed that a significant release of carbohydrates during the digestion process, peaking within the first 15 min of the intestinal phase (421.4 ± 5.82 mg GE/g, dry weight, respectively), was observed, and the phenolic release reached the highest in the first 15 min of the gastric phase. Meanwhile, the bioaccessibilities of phenolic compounds and carbohydrates were determined to be 63.87% and 80.40%, respectively, after intestinal digestion. In addition, the undigested fractions of goji berries could be further fermented to produce short-chain fatty acids, which decreased the colon pH value (from 7.38 to 6.71) as well as the Firmicutes/Bacteroidetes ratio. Moreover, the goji berries regulated the composition of gut microbiota by promoting beneficial bacteria such as Bacteroides, Parabacteroides, and Paraclostridium, whereas inhibiting the proliferation of harmful bacteria (e.g., Fusobacterium). Our results indicated that the goji berry exhibited significant bioactivity during the digestion and fermentation stage and might provide some new insights into the utilization of goji berries in healthy food processing.

What if you eat nanoplastics? Simulating nanoplastics fate during gastrointestinal digestion.

Despite our growing awareness of micro-and nanoplastics presence in food and beverages, the fate of nanoplastics (NPs) in the human gastrointestinal tract (GIT) remains poorly investigated. Changes of nanoplastics size upon digestive conditions influence the potential of absorption through the intestine. In this study, polymer nanoparticles with different physicochemical properties (size, surface and chemistry) were submitted to gastrointestinal digestion (GID) simulated in vitro. Their agglomeration behaviour was measured with a unique set of analytical approaches, allowing to study NPs' interactions with the digestive enzymes. Smaller NPs agglomerated more, narrowing the overall particle size distribution of smaller and larger NPs. NPs of different polymers exhibited heteroagglomeration. Digestive enzymes interact with the NPs, forming large but fragile agglomerates. In presence of the enzymes, even acid-functionalized NPs, typically stable in harsh conditions, agglomerated similarly to the non-functionalized PS NPs. These results highlight the role of the GID in increasing the effective size of ingested NPs, potentially reducing their ability to pass through the cell membranes. Our findings address a critical knowledge gap in nanoplastics oral uptake potential, providing a solid technical foundation for their characterization.

Study on encapsulation of Lactobacillus plantarum 23-1 in W/O/W emulsion stabilized by pectin and zein particle complex.

This study was conducted to develop a W/O/W emulsion encapsulated Lactobacillus plantarum 23-1 (LP23-1) to significantly enhance the survival rate of LP23-1 under simulated digestion and storage conditions. The zein particles and pectin formed a complex through electrostatic interaction and hydrogen bonding. When the proportion of zein particles to pectin was 1:1, the emulsifying stability index (ESI) was 304.17 %. Additionally, when the proportion of the internal aqueous phase to the oil phase was 1:9, the polyglycerol polyricinoleate (PGPR) concentration was 5 %, the proportion of primary emulsion to the external aqueous phase was 5:5, the zein particles concentration was 4 %, and the proportion of zein particles to pectin was 1:1, the encapsulation rate was the highest at 96.27 %. Cryo-scanning electron microscopy and fluorescence microscopy confirmed the morphology of W/O/W emulsion and successful encapsulation of LP23-1. Furthermore, compared with free LP23-1, the W/O/W emulsion encapsulation significantly improved the survival rate of LP23-1 to 73.36 % after simulated gastrointestinal digestion and maintained a high survival rate of 78.42 % during the 35-day storage. The W/O/W emulsion was found to effectively improve the survival rate of LP23-1 during simulated digestion and storage, which has implications for the development of probiotic functional foods with elevated survival rates.

The Effects of Nitrogen Application and Varietal Variation on the Product Quality and In Vitro Bioaccessibility of Bioactive Compounds of Baby Spinach Varieties Grown in a Soilless Growth Medium.

Baby spinach is becoming increasingly popular as a salad ingredient and needs high fertiliser rates to grow well and attain higher-quality leaves (dark green leaves). Chemical fertilisers, especially nitrogen (N), boost yields. There are many risks associated with nitrogen fertilisation. Additionally, spinach contains phenolic compounds and carotenoids. Nitrogen fertilisation affects growth, development, yield and metabolites. This study examined the impact of lower concentrations of N (0, 30, 60, 90, 120, 150 mg/L) on yield and colour properties [light intensity (L*) colour coordinates, unique for green colour (a*) and yellow colour (b*)], as well as the impact of varying N concentrations on the total phenolic content and p-coumaric acid, quercetin, ferulic acid, kaempferol, lutein, zeaxanthin, ß-carotene and antioxidant activities in the baby spinach varieties 'Acadia', 'Crosstrek' and 'Traverse', and it was established that N fertilisation improves phytochemical bioaccessibility and antioxidant activity. In a split strip plot design, three baby spinach varieties were treated with different N concentrations, including 0, 30, 60, 90, 120 and 150 mg/L. For 40 days, three baby spinach varieties were grown on soilless Mikskaar Professional substrate 300. During both seasons, 'Crosstrek' had the highest fresh mass (921.4 g/m2, 856.3 g/m2) at 120 mg/L N, while 'Traverse' had the highest fresh mass at 554.8 g/m2 and at 564.3 g/m2 at 90 mg/L N and did not differ significantly from 90 to 150 mg/L N during either season. During both seasons, 'Acadia' at 90 mg/L N increased fresh mass to 599 g/m2 and 557.9 g/m2. The variety × N supply interaction significantly affected the leaf colour; chlorophyll content across seasons; the levels of bioactive compounds, p-coumaric acid, quercetin, ferulic acid, kaempferol, lutein, zeaxanthin and ß-carotene in spinach varieties; the in vitro bioaccessibility; and the antioxidant activity. Varietal differences influenced the bioaccessibility of phenolic compounds and carotenoid components. The appropriate N levels can be used during plant cultivation to optimise the bioaccessibility of this spinach variety. Thus, fertilising 'Traverse' with 90 mg/N mL increased the in vitro bioaccessibility of ß-carotene (35.2%), p-coumaric acid (7.13%), quercetin (8.29%) and ferulic acid (1.92%) without compromising the yield.

Acrylamide and HMF occurrence and bioaccessibility in instant coffee and coffee substitutes. A study on isolated and milk-combined beverages.

This research evaluated the occurrence and bioaccessibility of acrylamide and HMF in commercial instant coffees (IC) and coffee substitutes (CS), considering both isolated consumption and combination with milk. There were no significant differences in acrylamide content between IC and CS samples (median: 589 vs. 671 µg/kg), but higher variability was reported for CS, probably due to their varied composition (roasted cereals, nuts, honey, dehydrated fruits, and/or chicory). Acrylamide level were always below the EU benchmark for each category. HMF contents were similar between both groups (1354-5127 mg/kg for IC and 735-7134 mg/kg for CS; median: 2890 vs. 2960 mg/kg), with no clear ingredient relationship. Since IC consumption by the Spanish population is ten times higher than that of CS, exposure to acrylamide and HMF was higher from IC (6.8 vs. 1.07 ng/kg body weight/day for acrylamide; 39.1 vs. 4.2 µg/kg body weight/day for HMF). The standardized in vitro gastrointestinal digestion protocol (INFOGEST) was used. The gastrointestinal process reduced the bioaccessibility of acrylamide up to 27.2 % in IC and to 22.4 % in CS, regardless of the presence of milk. HMF bioaccessibility from IC significantly dropped after the gastrointestinal digestion, whereas it greatly increased for CS. The presence of milk did not affect HMF bioaccessibility. These results highlight the importance of assessing food bioaccessibility in typical consumption scenarios, providing a holistic view and a realistic evaluation of the potential risks associated with acrylamide and HMF exposure in the diet.

Gastrointestinal digestion of yerba mate, rosemary and green tea extracts and their subsequent colonic fermentation by human, pig or rat inocula.

Polyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-O-caffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.

Bioaccessible Phenolic Alkyl Esters of Wine Lees Decrease COX-2-Catalyzed Lipid Mediators of Oxidative Stress and Inflammation in a Time-Dependent Manner.

Lipophenols, phenolic compounds esterified with fatty alcohols or fatty acids, provide greater health benefits upon dietary ingestion of plant-based foods than unesterified (poly)phenols. Based on this premise, the present study aimed to demonstrate the role of gastrointestinal enzymes (pepsin, pancreatin, and pancreatic lipase) in releasing alkyl gallates and trans-caffeates from wine lees, providing bioactive compounds with enhanced capacities against oxidative stress (OS) and para-inflammation. The UHPLC-ESI-QqQ-MS/MS-based analysis revealed ethyl gallate and ethyl trans-caffeate as the most prominent compounds (1.675 and 0.872 µg/g dw, respectively), while the bioaccessibility of the derivatives of gallic and caffeic acids was dependent on the alkyl chain properties. The de novo formation of alkyl gallates during gastric and intestinal digestion resulted from intestinal enzyme activity. Moreover, the in vitro capacity of bioaccessible alkyl esters of gallic and trans-caffeic acids to reduce cyclooxygenase-2 concentration and modulate oxilipins related to OS (8-iso-PGF2α) and inflammation (PGF2α and PGE2) was demonstrated in a time-dependent manner. In conclusion, the presence of alkyl esters of gallic and trans-caffeic acids in wine lees and their subsequent formation during digestion of this byproduct emphasize their value as a source of antioxidant and anti-inflammatory compounds, encouraging the consideration of wine lees as a valuable ingredient for health-promoting coproducts.

γ-Conglutin Immunoreactivity Is Differently Affected by Thermal Treatment and Gastrointestinal Digestion in Lupine Species.

Lupine is a legume commonly used in human diet as a functional food due to its high nutritional content and important technological properties. However, its consumption can lead to the manifestation of adverse immunological reactions, posing significant health issues in sensitized/allergic patients. This work aims to investigate the effect of food processing combined with simulated gastrointestinal (GI) digestion on the immunoreactivity of lupine γ-conglutin. Model foods of wheat pasta containing 35% of lupine flour (Lupinus albus, L. luteus, and L. angustifolius) were prepared and submitted to a boiling process. The proteins were extracted and their profiles characterized by SDS-PAGE. Simulated GI digestion was performed on thermally treated pasta using the INFOGEST harmonized digestion protocol 2.0. The IgG binding capacity of γ-conglutin was assessed by immunoblotting in non-reducing conditions and indirect ELISA with specific antibodies. Results demonstrate that the boiling treatment affected the immunoreactivity of the three lupine species differently. Simulated GI digestion led to extensive destruction of the protein structure, more significant in the intestinal phase, reducing but not abolishing the IgG affinity to γ-conglutin and its potential presentation to immunocompetent cells. This information can offer valuable insights to the food industry for developing food formulations with reduced allergenic properties.