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[hal-05653224] Complexation of alginate with linear and branched polyethyleneimine
This study investigates the complexation behavior of alginate (ALG), a naturally occurring anionic polysaccharide, with two different molecular architectures of synthetic cationic polyethyleneimine (PEI): linear (l-PEI) and branched (b-PEI). While PEI/ALG interactions have been studied for various biomedical and industrial applications, a quantitative assessment of how PEI architecture affects phase behavior, charge compensation, and thermodynamics under varying ionic strengths remains unexplored. To fill this gap, we employ a combination of complementary techniques, including millifluidic droplet assays, isothermal titration calorimetry (ITC), conductometric titration, turbidity analysis, and optical microscopy. We reveal that b-PEI, due to its branched configuration and higher charge density, forms complexes and coacervates that are more stable and salt-resistant than l-PEI. Notably, b-PEI enables coacervation to persist up to 1.8 M NaCl, over twice the maximum salt concentration tolerated by complexes involving l-PEI. ITC thermograms reveal a biphasic, architecture-dependent binding mechanism and a pronounced enthalpic asymmetry on titration direction. These findings offer valuable mechanistic insights into how polymer structure governs polyelectrolyte complexation, enabling the rational design of customizable materials for applications in drug delivery, tissue engineering, and colloidal stabilization.
ano.nymous@ccsd.cnrs.fr.invalid (Asna Vakeri) 16 Jul 2026
https://hal.inrae.fr/hal-05653224v1
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[hal-05620225] Less for more : Lower initial protein concentrations enhance the linear viscoelasticity of heteroprotein complex coacervates
Heteroprotein complex coacervation is exploited in biopolymer-based systems for food or pharmaceuticals. While the effects of pH, ionic strength, and charge stoichiometry have been widely investigated, the role of the initial total protein concentration in governing the properties of the resulting dense phase remains insufficiently understood. Here, we systematically examine coacervates formed by -lactoglobulin and lactoferrin over a broad range of initial total protein concentrations (3.75–30 g/L). Surprisingly, rheological measurements show that decreasing the initial protein concentration leads to a marked increase in viscoelastic properties, with the complex modulus increasing from 38.5 ± 5.1 Pa to 1563.9 ± 78.7 Pa. Time–temperature superposition is valid for all coacervate systems, and comparable activation energies are obtained (50–100 kJ/mol), indicating that decreasing the initial total protein concentration does not modify the fundamental stress relaxation mechanism but instead affects the structural organization of the coacervate phase. Gravimetric analysis reveals a small yet systematic reduction in water content, from 70% to 65%, as the initial total protein concentration decreases (30 to 3.75 g/L). Consistently, small-angle X-ray scattering shows a decrease in the correlation length from 95 to 86 Å (30 to 7.5 g/L), demonstrating that coacervates formed at lower initial concentrations adopt a more compact structure. These results demonstrate that small changes in hydration and intermolecular spacing induce large variations in viscoelasticity. The initial total protein concentration emerges as a key parameter controlling the structure and viscoelasticity of heteroprotein complex coacervates, providing new insight for the rational design of food-grade soft materials.
ano.nymous@ccsd.cnrs.fr.invalid (Ghazi Ben Messaoud) 19 May 2026
https://hal.inrae.fr/hal-05620225v1
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[hal-05688206] Evidencing strain-dependency of metabolic pathways within 1,494 lactic bacteria genomes with the in silico screening Prolipipe pipeline
Genomes from bacteria of interest to the food industry exhibit significant functional variability, yet evaluating this characteristic remains challenging. As public repositories continue to accumulate more genomes, large-scale assessment of metabolic potential emerges as a promising method to highlight this functional variability. The primary challenge lies in automating a workflow to construct metabolic networks from genomes on a massive scale. Here, we present Prolipipe, a pipeline designed for the large-scale assessment of metabolic potential in bacteria, focusing on specific pathways. Given a large dataset of hundreds to thousands of bacterial genomes with known taxonomy and a list of targeted pathways, Prolipipe identifies gene functions through a comprehensive annotation step using three different tools. Then it builds genome-scale metabolic networks for each genome. These networks are then parsed to document the presence or absence of each reaction across all processed genomes. The pipeline evaluates the metabolic potential of each genome to carry out the pathway according to its gene content and highlight the best candidates among the large-scale set of genomes. In this study, Prolipipe was applied to 1,494 genomes of lactic acid bacteria, assessing the completeness ratio of 761 pathways. We classified pathways according to their maximum completeness rate, revealing that 137 pathways can be operated by at least one strain in our dataset. By mapping the identifiers of these pathways onto the pathway ontology graph of the Metacyc database, we highlighted that none of the pathways within four functional classes of Metacyc can be entirely recovered in the strain dataset. We then investigated infraspecific variability, a strong indicator of functional variability, and compared the species in our genome dataset based on their tendency to exhibit infraspecific variability. This analysis revealed species potential for strain-dependency, where phenotypes differ among strains of the same species.
ano.nymous@ccsd.cnrs.fr.invalid (Noé Robert) 10 Jul 2026
https://hal.science/hal-05688206v1
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[hal-05668374] In silico and in vitro screening of non-Saccharomyces yeast strains for their ability to produce nicotinate
Nicotinic acid (NA) and nicotinamide adenine dinucleotide phosphate (NADP) are two of the most consumed vitamers of vitamin B3 by Saccharomyces cerevisiae during fermentation (Evers et al. 2025). In absence of oxygen, the concentration of NA appeared as a limiting factor. Suboptimal levels of NA correlate with a slower fermentation, a reduced biomass, and possibly with an altered metabolite production (Duncan et al. 2024). We hypothesise that the NA concentration in the fermentation medium could be increased by inoculating a non-Saccharomyces species that can produce and release NA. To assess the potential of different non-Saccharomyces species, we reconstructed and compared the NA biosynthetic pathways from genomic sequences corresponding to 20 different species of interest in the food industry. To evaluate the potential of the selected non-Saccharomyces species to supplement fermented beverages in NA, strains harbouring a complete NA biosynthetic pathway were phenotyped for their ability to ferment various carbon sources found in grape juice (glucose, fructose, citric and malic acid), fruit kefir (sucrose, citric acid), beer (glucose, fructose, sucrose, maltose), milk (lactose, citric acid) and soy juice (sucrose, raffinose, stachyose and citric acid). Double in silico and in vitro screening revealed non-Saccharomyces species able to grow in fruit kefir, beer, milk, soy and/or grape juice and which may provide NA at the benefit of Saccharomyces cerevisiae species. Further experimental growths of non-Saccharomyces species associated with NA quantifications must be performed to validate these results. This project will pave the way for a better understanding of the molecular basis of the commensalism between non-Saccharomyces species and Saccharomyces cerevisiae.
ano.nymous@ccsd.cnrs.fr.invalid (Hélène Falentin) 26 Jun 2026
https://hal.inrae.fr/hal-05668374v1
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[hal-05685054] Toward a supervised machine learning approach to predict the properties of lignocellulosic filler/PHBV-based biocomposites
Biocomposites made from polyhydroxyalkanoates and lignocellulosic fillers are gaining traction as biodegradable and sustainable materials that can be used in applications such as vine clip or food packaging. In this study, supervised machine learning was used to predict the performance of several polymer-based biocomposites. An original dataset compiled from experimental trials was analyzed using classification models to predict the degradation of six main functional properties (mechanical properties, water vapor permeability, and thermal stability) related to filler content and key intrinsic properties (biochemical composition and apparent median diameter (D50)). The best-performing machine learning models were evaluated using the F1 score to ensure accuracy, precision, and model reliability. SHapley Additive exPlanation (SHAP) values were used to enhance interpretability and revealed the dominant role of filler content and size on most of the composite properties. As a complement to these results, an abacus was also created to provide an intuitive visualization that could suggest new experimental trials based on specific requirements for the final biocomposites. This integrative, data-driven approach not only advances the predictive design of eco-friendly biocomposites but also offers a novel framework for optimizing the performance of materials while minimizing environmental and production costs.
ano.nymous@ccsd.cnrs.fr.invalid (Mélanie Munch) 09 Jul 2026
https://hal.science/hal-05685054v1
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[hal-05670802] The probiotic bacterium Propionibacterium freudenreichii prevents food allergy in mice via an immunomodulatory mechanism involving the surface layer protein SlpB
Introduction and Objectives The prevalence of food allergies has increased in recent decades in industrialized countries (1). These allergies are influenced by environmental factors from a very young age, particularly by the first colonizers of the gut microbiota (2). With limited therapeutic options, the lack of effective treatments has led to the search for new approaches, including biotherapies. Promising results suggest that immunomodulatory probiotic bacteria, in particular, could offer new biotherapeutic or preventive strategies to address the increasing prevalence of food allergies (3). In this context, we investigated the potential impact of Propionibacterium freudenreichii CIRM-BIA129, a recognized immunomodulatory probiotic bacterium (4), on the development of food allergies in a mouse model. More precisely, the modulatory effect of this probiotic on the development of food allergy to wheat gliadin was investigated. Materials and Methods The preventive effects of this probiotic were evaluated in the context of a wheat gliadin-induced allergy. During 30 days, mice received by oral gavage either a sham control, or Propionibacterium freudenreichii CIRM-BIA129 (109 CFU/mL), or a mutant derived from it by the inactivation of the slpB gene. During this period, mice were also sensitized to wheat gliadin by intraperitoneal injection (20 μg) at days 0, 11, 18 and 24. Following this sensitization, an oral challenge was then applied at day 30 by oral administration of 20 mg of gliadin. Clinical and immunological parameters were then monitored. These include body temperature, serum immunoglobulins, cytokines, gut permeability, as well as expression of key genes in intestinal tissues. Results, Discussion, and Conclusion When administered orally, the Propionibacterium freudenreichii CIRM-BIA129 strain prevented induced allergy to wheat gliadin. In mice, administration of this probiotic promoted the differentiation of Treg lymphocytes at the expense of Th2 lymphocytes. Notably, the Propionibacterium freudenreichii CIRM-BIA129 ΔslpB strain, carrying a mutation in the slpB gene encoding a surface protein essential for adhesion and immunomodulation, did not induce the same phenotype and did not prevent allergy. Similarly, the wild-type strain stimulated IL-10 production by human PBMCs, unlike the mutant strain. These results indicate that the Propionibacterium freudenreichii CIRM-BIA129 strain can attenuate the allergic food response through its immunomodulatory effects, mediated by the surface protein SlpB. This discovery opens new avenues for biotherapies aimed at managing the increasing prevalence of food allergies.
ano.nymous@ccsd.cnrs.fr.invalid (Gwénaël Jan) 26 Jun 2026
https://hal.inrae.fr/hal-05670802v1
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[hal-05674315] Bacterial extracellular vesicles as postbiotic effectors: Insights from Propionibacterium freudenreichii in host interactions and inflammation
Probiotics exert beneficial effects on host health through complex and not yet fully understood mechanisms mediated by multiple factors, including surface-exposed proteins involved in host interaction and the release of bioactive compounds (e.g., butyrate, GABA) that modulate host physiological and immune responses. During their biosynthesis, these molecules can be encapsulated within extracellular vesicles (EV) produced by probiotics, which protect them from degradation and enhance their stability. EV are nano-sized, membrane-bound particles produced by almost all cells and released into the extracellular environment. They have recently emerged as key mediators of bacteria-host interaction by enabling the transport and targeted delivery of bioactive molecules to host cells. As such, EV are increasingly recognized as a key postbiotic component contributing to the health-promoting effects of probiotics. In this context, Propionibacterium freudenreichii, a well-established probiotic used in fermented dairy products with documented anti-inflammatory properties, represents a particularly relevant model to investigate the role of EV in bacteria-host interactions. Here, we present current knowledge on P. freudenreichii-derived EV and their role in host interactions and inflammation. This work identifies probiotic EV as critical effectors of host communication and provides novel insights into their potential use as postbiotic agents for the development of innovative strategies to improve host health through bacteria and microbiota-derived vesicles.
ano.nymous@ccsd.cnrs.fr.invalid (Eric Guédon) 30 Jun 2026
https://hal.inrae.fr/hal-05674315v1
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[hal-05612238] Bioaccessible fraction of proteins obtained after in vitro digestion: Impact of the fractionation method on the peptide profile
Protein digestibility can be determined in vitro from the digesta bioaccessible fraction. Different fractionation methods were compared on casein, ovalbumin, gelatin, lupin and pea globulins digested at high (INFOGEST protocol) or low extent (enzyme reduced 10×). Digesta were centrifuged, alone or after trichloroacetic acid (TCA, 3 or 8.5%), sulfosalicylic acid (SSA, 1.5 or 4.5%) or methanol (80%) precipitation. The supernatants were analyzed by size exclusion chromatography. Real in vitro digestibility values of 15 N-labelled casein were compared with those obtained in vivo. Only the chemical agents, offering similar efficiency except methanol and 1.5% SSA somehow differing, allowed large peptide (>10 kDa) depletion. The effectiveness of chemical agents depended both on the protein source and their digestion extent. The real digestibility of casein could be determined appropriately in vitro using 4.5% SSA or methanol, with values similar to that measured previously in humans, at the ileal level, on the same protein source.
ano.nymous@ccsd.cnrs.fr.invalid (Simon Pogu) 05 May 2026
https://hal.science/hal-05612238v1
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[hal-05642604] Integrated resonant photonic sensors for real-time monitoring of drying dynamics in opaque industrial and dairy-based colloids
This work presents an integrated optical approach for the real-time study of drying dynamics in opaque colloidal systems. The resonant structure consists of UV210 organic Micro-Resonators (MRs) fabricated via deep ultraviolet (DUV) photolithography on oxidized silicon substrates. Integration of the photonic chip within an optical test platform enables in situ, non-destructive, and real-time monitoring of film formation and structural evolution during the evaporation and drying processes of aqueous latex and dairy-based solutions. These systems are typically challenging to investigate using conventional optical methods and commercial device due to strong absorption and scattering effects. By a quasi-surface analysis method and by tracking the evolution of the Free Spectral Range (FSR) throughout the drying process, characteristic signatures of phase transitions, particle rearrangement, and surface morphology were identified. In latex dispersions, the technique discriminates between particle populations of different sizes, revealing distinct film formation behaviours linked to surface roughness and coalescence mechanisms. For dairy products, experiments on whey protein isolates (WPI), native phosphocaseinates (NPC), and their mixtures demonstrate sensitivity to sol-gel transitions, deformation, and potential stratification phenomena in mixed systems. The results highlight the MRs ability to probe opaque solutions through the evanescent tail of the guided optical mode. Particle migration and rearrangements induced by Marangoni flows, leading to solution instabilities, were also observed. This integrated resonant platform therefore offers a powerful analytical tool for the formulation optimization and quality control of opaque industrial materials during drying processes.
ano.nymous@ccsd.cnrs.fr.invalid (Jordan Gastebois) 03 Jun 2026
https://hal.science/hal-05642604v1
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[hal-05497276] MRI monitoring of digestion mechanisms at the scale of a food piece: proof of concept with bread
To improve our understanding of gastrointestinal digestion of solid foods, spatially resolved insights into disintegration mechanisms at the particle level are needed. Magnetic resonance imaging (MRI), despite its noninvasive and multiscale capabilities, remains underexploited for such purposes. This study pursued two objectives: (1) to develop an MRI-compatible miniaturized setup for static in vitro oral-gastric-intestinal digestion, and (2) to apply this system to investigate online the digestion of a bread piece measuring a few millimetres using MRI (UTE 3D morphometric imaging and T 2 mapping), supplemented by chemical analyses of starch and protein hydrolysis. The setup comprises a circulation loop of the digestion fluid, linking an MRI-compatible digestion cell to a remote pH-stat system, which enables real-time control of temperature, pH, enzyme addition, and sampling. MRI results correlated well with peptide and polysaccharide release kinetics in the digestion fluid. UTE 3D imaging showed stable bread volume during gastric digestion, followed by volume loss, surface roughening, and fluid ingress into pores during intestinal digestion, consistently with gluten hydrolysis. T 2 analysis distinguished more mobile water in the pores and less mobiles ones in bread. An increase in the amount of more mobile protons suggested erosion-driven exposure and internal enzymatic attack. The release of starch hydrolysis products was shown to be independent on the breakdown of the gluten network and could be monitored with T 2 in the digestion fluid. In conclusion, this MRI-compatible setup enables time-lapse, submillimetric resolution monitoring, offering valuable insights into bread piece digestion, and could be adapted to various solid food matrices.
ano.nymous@ccsd.cnrs.fr.invalid (Ruoxuan Deng) 06 Feb 2026
https://hal.inrae.fr/hal-05497276v1
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[hal-05640340] Towards an international consensus infant in vitro digestion model for different ages: from prematurity to maturity
Intro Understanding infant digestion remains a scientific challenge due to the absence of fully consensual in vitro models covering early life stages. To address this gap, a group of over 16 experts from 7 countries within the INFOGEST network conducted a systematic review of available physiological data. This initiative aimed to define a consensual framework for infant digestion from the preterm until the mature stage. Materials and Methods First, the different preterm stages were defined based on gestational age at birth and infant age at the time of the study. A comprehensive review of the scientific literature was then conducted, including a large number of publications reporting gastrointestinal parameters in infants in comparison with adults. Four physiological stages were defined: preterm, 1 month, 6 months and mature. Extracted data included gastric emptying kinetics, pH values, enzyme activities, food to secretion ratios. Recent studies provided updated information on gastric emptying and pH evolution, whereas older but still relevant publications informed on enzyme concentrations. Results The analysis revealed substantial variability in reported physiological values, confirming the need of harmonized parameters. A few parameters were found to substantially vary during infancy. Particularly, gastric pH decreased after meal ingestion, reaching values of approximately 4 in preterm and 1-month-old infants and around 2 at 6 months of age, which is comparable to adult. Pepsin activity increased markedly from birth to 6 months, reaching approximately 71 U/mL/kg of body weight, while pepsin and pancreatic lipase seem to mature progressively until 2 years of age, when they reach a level similar to adult (2,000 U/mL for both enzymes). Bile salts concentrations increased throughout infancy, from approximately 1.6 mM in preterm infants to 4.3 mM at 6 months of age, and up to 10 mM at maturity. Trypsin is present at a mature level at birth; however, enterokinase, which activates trypsin, is immature, resulting in only 17% to 38% of effective trypsin activity from the preterm stage to 6 months of age. Conversely, other parameters—such as gastric lipase (mature at birth), gastric emptying rate, intestinal pH, duration of the intestinal phase, dilution of intestinal contents by secretions—remained relatively stable throughout infancy. However, the authors were also confronted with a lack of infant digestion data e.g. older infants or some intestinal parameters of any ages. Conclusion Based on the expert consensus and data consolidation, parameters for in vitro gastrointestinal digestion models are proposed for preterm, 1- month-old and 6-month-old infants in comparison with adults. These settings will be applicable for static, semi-dynamic, and dynamic in vitro digestion systems. Complementing the models developed within the INFOGEST network for adults and the elderly, this latest development will ultimately enable us to cover all stages of life.
ano.nymous@ccsd.cnrs.fr.invalid (Olivia Ménard) 01 Jun 2026
https://hal.inrae.fr/hal-05640340v1
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[hal-05627429] Revisiter les itinéraires de production des poudres de lait infantile pour concilier qualité et durabilité.
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ano.nymous@ccsd.cnrs.fr.invalid (Sergine Even) 20 May 2026
https://hal.inrae.fr/hal-05627429v1
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[hal-05640035] Saliva modulates the impact of tannins on the mucus layer of intestinal cells
Dietary tannins may interact with host proteins such as salivary proteins including mucins or digestive enzymes, but less is known about their interaction with intestinal mucins. The present study aimed at testing the hypotheses that tannins reaching the intestine affect the mucin layer lining the epithelial cells, and that previous complexation of tannins with salivary proteins modify this impact. A polyphenol extract was obtained from “Dous Möen” cider apples: it contained 730mg/g of total polyphenols, of which 322 mg/g were condensed tannins. This extract, in absence or presence of saliva at a ratio of 0.08 g of polyphenols per g of protein, was digested following a slightly modified version of the static INFOGEST 2.0 protocol. Digests were applied for 2 hours to Caco-2/HT29-MTX co-cultured cells, where mucins are secreted. Cultures were fixed and double-stained for F-actin using rhodamine-phalloidin (as an indicator of the cytoskeleton), and for sialic acid using WGA-Alexa488 (as an indicator of mucins). The structure of the mucous layer was explored by confocal microscopy. Ten to fifteen 3-D images (consisting of around 80 stacked images on average) were acquired per experimental condition. The open-source software ilastik was used to segment images: pixels were manually annotated from 20 images as part of bright mucin staining, weak mucin staining or background and a classifier was trained. Images were then segmented with this classifier. Quantitative data were extracted: average thickness, volume and proportion of dense (brightly stained) mucus. Confocal microscopy evidenced that cultures showed a clear topographic pattern with domes (pseudo villi) whose height was around 70 µm on average. Brightly-stained mucin clusters were visible in the extracellular apical space particularly on top of the previously mentioned domes, which suggests that the mucin-secreting HT29-MTX cells are concentrated in such regions. Overall, digested tannins (whether in presence of saliva or not) increased significantly the height of the pseudo villi observed on the cell culture (65.5 ± 12.8 vs 74.2 ± 12.1 µm). Tannins also reduced the volume and significantly the proportion of the dense mucus on cells compared to the blank (cells exposed to digestive medium without tannins). Interestingly, this effect was not retained when tannins had been mixed with saliva prior to digestion. This suggests that an in-mouth event, namely interaction of polyphenols with saliva, may have digestive consequences as far as in the intestine.
ano.nymous@ccsd.cnrs.fr.invalid (Yann Le Gouar) 01 Jun 2026
https://hal.inrae.fr/hal-05640035v1
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[hal-05640062] Modulation of trypsin activity in the presence of polyphenols and/or salivary protein-polyphenols complexes
Polyphenols are specialized metabolites produced by plants with a well-documented overall health effect. They are also described in the literature to interact with proteins with possible impacts on protein functionality. In the context of digestion, polyphenols can interact with host proteins in the mouth for example salivary proline rich proteins (PRPs), or in the digestive tract, for example digestive enzymes such as trypsin or pepsin. PRPs have long been considered as protective against the detrimental effect of tannins on digestive proteolysis by binding tannins before they can interact with digestive enzymes. In this study, we tested this hypothesis: we examined the proteolytic activity of trypsin by using whey protein isolate (WPI) as substrate in the presence of epigallocatechin gallate (EGCG) or EGCG and PRP. Fresh saliva was collected from a donor at least one hour after any meal or dental hygiene procedure followed by a clarification step by centrifugation. Higher molecular weight proteins were removed using Vivaspin concentrators equipped with 30 kDa molecular weight cut-off membranes. SDS-PAGE electrophoretic profiles confirmed that the ultrafiltrate was depleted from high molecular weight proteins, and that bands most likely corresponding to PRPs were present. The ultrafiltrate was further concentrated by drying: the protein content of the extract was 7.2 mg/ml, approximately ten times more than in fresh saliva. Trypsin activity measurement was adapted from Borgonovi et al. (2025). The final concentration for proteins (WPI or WPI+salivary proteins), trypsin and EGCG were set at 20 g/L, 5 mg/L and 1 mM, respectively. After stopping trypsin activity after 10, 20 and 30 min, samples were centrifuged to precipitate higher molecular weight proteins. Released peptides were quantified by reading optical density at 280 nm in the supernatant. In the presence of EGCG, we observed a ~24% inhibition of trypsin proteolytic activity. When salivary proteins were added, a ~78% reduction in trypsin activity was observed. Our preliminary results suggest that EGCG impacts negatively trypsin activity, and contrarily to what is usually admitted, that the presence of low molecular weight salivary proteins enhanced this inhibition. A thorough description of the formation of binary or ternary complexes between EGCG, WPI and PRPs would provide useful information on the mechanisms at the origin of trypsin inhibition. Because polyphenol structure is very described in literature as an important factor influencing protein polyphenol interactions, further work is currently on-going on other polyphenols with different structural feature and higher degree of polymerization. Assays on pepsin activity will also be conducted. This work adds knowledge on the role of saliva in bioaccessibility of food proteins and/or polyphenols.
ano.nymous@ccsd.cnrs.fr.invalid (Amadou Adama Coulibaly) 01 Jun 2026
https://hal.inrae.fr/hal-05640062v1
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[hal-05642101] PH VARIATION IN THE STOMACH AND DUODENUM AFFECTS CALCIUM BIOACCESSIBILITY: AN IN VITRO STUDY USING THE 3-COMPARTMENT DIDGI DIGESTION SIMULATOR
Calcium absorption is controlled by complex homeostatic mechanisms and highly driven by its solubility in the gastrointestinal tract. Calcium solubility is sensitive to the physicochemical conditions, particularly the pH, which varies considerably along the gastrointestinal tract and differs between the duodenum and the jejunum/ileum. Yet, most in vitro digestion studies have focused on calcium solubility at a fixed pH in the jejunum/ileum compartment without considering the pH in the duodenum. The objective of this study was, firstly, to design a dynamic in vitro digestion model using the 3-compartment DIDGI® system (stomach, duodenum, jejunum/ileum) and find physiological parameters to program it to simulate the evolution of pH in the 3 compartments. The data used to define the pH variations, particularly in the duodenum, came from in vivo studies conducted on humans and pigs using microelectrodes or a pH catheter after ingestion of a liquid meal. Secondly, the digestive system was tested on four commercially available food matrices (milk, yogurt, enriched calcium soy dessert and beverage) to measure the solubility and bioaccessibility of calcium and the effect of pH on these properties. The soluble and total calcium contents were measured at different stages of gastric, duodenal, and intestinal (jejunal/ileal) digestion using inductively coupled optical emission spectrometry. To avoid biases caused by dilution and matrix depletion, calcium bioaccessibility was determined by the ratio of the soluble calcium fraction to the total calcium fraction present during digestion. Although the milk and soy beverage matrices did not contain the same amount of calcium (1.2 vs. 1.6g/L, respectively), gastric acidification (pH 7 to 3) induced a same progressive increase in calcium solubility in both matrices. This was also the case during the duodenal phase (pH 5.7 to 4.35), when calcium bioaccessibility in both milk and soy beverage reached nearly 80%, after 3h of digestion. However, calcium bioaccessibility was significantly higher in the first part of the duodenal phase for milk compared to soy beverage (38% vs. 21% at 15min; 48% vs. 33% at 21min). Given the rapid transit time through the duodenum (15 min), this could indicate that at this stage, a larger amount of soluble calcium from milk is absorbed compared to that from soy beverage. Conversely, the pH rose to 6.5 in the intestinal phase and induced a decrease in calcium solubility. Overall, calcium bioaccessibility in the intestinal phase was similar between milk and soy beverage (26-28%, respectively, t120min). For gel matrices, yogurt showed a higher calcium bioaccessibility than soy dessert. The newly developed three-compartment digestive model allowed a fine assessment of calcium bioaccessibility in the duodenum and jejunum/ileum. The higher calcium content in soy dessert and beverage did not increase the amount of soluble calcium being produced during digestion compared to yogurt and milk.
ano.nymous@ccsd.cnrs.fr.invalid (Rozenn Le Foll) 03 Jun 2026
https://hal.science/hal-05642101v1
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[hal-05646007] Microfluidic investigation of dairy fouling dynamics
Understanding fouling formation and preventing its consequences are crucial in the dairy industry to improve the efficiency of unit operations and the quality of the products. To date, most of the literature associated dairy fouling development with the heat-induced denaturation of whey proteins, which leads to their aggregation and progressive adsorption onto surfaces. Nevertheless, this hypothesis has a major flaw: fouling also occurs at temperatures below the denaturation threshold (≈ 70°C). This is the case, for example, in falling-film evaporators, used in the dairy industry for vacuum concentration prior to spray drying. These considerations highlight the need to explore the impact of other process parameters, besides temperature, to fully understand fouling. However, shedding light on fouling dynamics is extremely challenging with the current experimental methods, given the size and structure of dairy equipment. Therefore, a real-time observation of the phenomenon is still lacking, especially at the micron scale. To address these crucial open questions, we employed an original rheofluidic approach to investigate the role of shear rate in the formation of dairy deposits. Our outcomes showed how, at sub-denaturation temperatures, shear not only increases the amount of whey protein deposits but also promotes their structural complexity. Encouraged by these results, we also performed direct observations of the fouling growth in microfluidic devices replicating the typical environmental and flow conditions of falling-film evaporators. These observations enabled the discrimination between the simultaneous and competitive mechanisms governing protein aggregation in the bulk solution and those occurring at the surface. This preliminary study also allowed for a first characterization of the kinetics of deposit growth. The miniaturization approach therefore proves to be effective in providing a better overview of the microscopic mechanisms leading to fouling propagation and of the factors influencing this phenomenon. This represents a first step toward the development of more comprehensive predictive models and innovative mitigation strategies.
ano.nymous@ccsd.cnrs.fr.invalid (M Grostete) 05 Jun 2026
https://hal.inrae.fr/hal-05646007v1
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[hal-05507741] Switching cell wall-bound polysaccharides to secreted polysaccharides in lactobacilli
Bacterial exopolysaccharides (EPS) are carbohydrate polymers secreted into the environment. EPS produced by lactic acid bacteria have many valuable properties in the food and health sectors. In this study, we isolated spontaneous mutants of lactobacilli that overproduce EPS, using a selection method based on their slow sedimentation rate in a semi-liquid medium. In the mutants selected from several strains, we detected a missense mutation in epsD, which encodes a tyrosine kinase, or an insertion in epsC, which encodes its transmembrane modulator. Both genes were located within a gene cluster involved in Wzy-dependent polysaccharide biosynthesis. We then characterized selected Lacticaseibacillus rhamnosus mutants in detail to gain insights into the mechanisms involved in EPS overproduction. We demonstrated that the single mutation D94L in the EpsD catalytic site prevents EpsD autophosphorylation. The chemical structure of the overproduced EPS was established, and consists of heptasaccharide repeating units with pyruvate substituents. In the wild-type parental strain, a polysaccharide with an identical structure was found covalently bound to the cell wall (CW) and covering the bacterial surface. In conclusion, our results indicate that the switch from CW-bound polysaccharides to EPS released into the environment is associated with a defect in autophosphorylation of the EpsD tyrosine kinase.
ano.nymous@ccsd.cnrs.fr.invalid (Saulius Kulakauskas) 12 Feb 2026
https://ulco.hal.science/hal-05507741v1
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[hal-05613790] Projet VEG&LAIT : Auto-tranformation de desserts mixtes à base de lait et de légumineuses
Dans un contexte de changements climatiques et de tensions économiques croissantes, le renforcement de l’autonomie des fermes laitières apparaît comme un levier essentiel pour améliorer leur résilience. Le développement de filières locales et la réduction de l’empreinte carbone des produits alimentaires constituent également des enjeux majeurs pour la durabilité des systèmes agricoles. Cela passera notamment par une complémentarité des protéines animales et végétales dans la consommation humaine [1,2]. Le projet VEG&LAIT vise à développer des desserts à base de lait et de légumineuses. Il s’appuie sur des fermes laitières spécialisées déjà engagées dans la transformation à la ferme, afin de proposer de nouveaux scénarios de production et transformation mixtes. Cette approche vise à accroître l’autonomie des exploitations et à diminuer l’empreinte carbone des produits en recherchant des rotations culturales plus respectueuses de l’environnement, tout en garantissant des produits sains et appréciés des consommateurs. La méthodologie repose sur la comparaison de six espèces de légumineuses : la féverole, le pois, le pois chiche, la lentille, le lupin et le soja. Ces espèces sont évaluées à la fois pour leurs caractéristiques agronomiques en régions Bretagne et Grand Est, et pour leur aptitude à la fabrication de crèmes dessert, « yaourts » ou crèmes glacées à base de lait et de légumineuses, notamment au regard des fonctionnalités technologiques et gustatives des farines. Les résultats montrent qu’aucune espèce n’est à exclure, ce qui renforce la résilience des fermes par la diversification des cultures possibles. Toutes donnent des desserts mixtes organoleptiquement satisfaisants. Certaines espèces, plus riches en amidon, permettent également de simplifier la liste des ingrédients. Sur le plan agronomique, certaines légumineuses apparaissent plus propices selon les deux régions étudiées, en raison de rendements et d’une stabilité supérieure face aux aléas climatiques. Ces résultats restent toutefois à consolider, le projet étant actuellement dans sa deuxième année. Au-delà des aspects techniques, ce projet contribue au développement de filières territorialisées en favorisant la coopération des opérateurs locaux. En conclusion, les mélanges lait-légumineuses apparaissent comme une voie prometteuse pour végétaliser et relocaliser l’alimentation sans compromettre le goût des produits. VEG&LAIT est soutenu par l’Agence Nationale de la Recherche via le financement France 2030 ANR-23-PLEG-0006.
ano.nymous@ccsd.cnrs.fr.invalid (Gabrielle Jagorel) 06 May 2026
https://hal.science/hal-05613790v1
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[hal-05674261] Boissons laitières issues de coproduits : Produire et distribuer durablement ; Projet EU-FAIRCHAIN
Le projet européen EU-FAIRCHAIN (2020-2024) a pour ambition de renforcer la durabilité du système alimentaire en développant des chaînes de valeur intermédiaires innovantes, adaptées aux besoins des petits et moyens acteurs. Fondé sur une démarche de co-création multi-acteurs et sur une évaluation croisant plusieurs perspectives (économique, environnementale et sociale), le projet a permis d’identifier des modèles économiques durables, circulaires et fortement ancrés dans les territoires, contribuant notamment à des stratégies zéro déchet. Cette intervention présentera la méthodologie élaborée pour concevoir et évaluer ces modèles économiques durables, avant d’en proposer une illustration dans le secteur laitier. L’accent sera mis sur des fromageries de taille intermédiaire qui valorisent encore peu, voire pas du tout, le lactosérum issu de leur production. Deux innovations majeures seront détaillées : • la valorisation du lactosérum sous forme de boissons fermentées à haute valeur ajoutée ; • la mise en place d’un système de réemploi des bouteilles consignées pour leur distribution, appuyé par un outil logiciel fondé sur des modèles d’analyses de cycle de vie simplifiés, destiné à concevoir des modèles logistiques régionaux zéro déchet. Enfin, les modèles économiques identifiés seront présentés, ainsi que les perspectives de développement et de valorisation de ces travaux à plus grande échelle.
ano.nymous@ccsd.cnrs.fr.invalid (Geneviève Gésan-Guiziou) 30 Jun 2026
https://hal.inrae.fr/hal-05674261v1
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[hal-05674165] Économie circulaire et boissons laitières : les innovations régionales FAIRCHAIN
Le projet européen EU-FAIRCHAIN (2020-2024) vise à renforcer la durabilité du système alimentaire en développant des chaînes de valeur intermédiaires innovantes, adaptées aux petits et moyens acteurs. Fondé sur une approche de co-création multi-acteur et une évaluation multi-perspectives, il a permis d’identifier des modèles économiques durables, circulaires et ancrés dans les territoires, contribuant notamment à des stratégies zéro déchet. Le séminaire met en lumière le cas d’étude français, dont l’objectif est d’accompagner des fromageries de taille intermédiaire et leurs partenaires dans la valorisation du lactosérum, jusqu’alors peu voire pas exploité. Deux innovations majeures seront présentées : le développement de boissons fermentées à base de lactosérum afin d’augmenter la valeur de ce coproduit, et la conception de l’outil logiciel SEAMPL, fondé sur des analyses de cycle de vie simplifiées, pour optimiser des modèles logistiques régionaux zéro déchet reposant sur le réemploi de bouteilles consignées. Des perspectives de développement et de valorisation compléteront la présentation.
ano.nymous@ccsd.cnrs.fr.invalid (Geneviève Gésan-Guiziou) 30 Jun 2026
https://hal.inrae.fr/hal-05674165v1
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[hal-05674135] Objectif Europe Leçons apprises du projet H2020-FAIRCHAIN
Ce séminaire propose une immersion analytique dans les coulisses du projet FAIRCHAIN, financé par le programme Horizon 2020. Mis en œuvre entre 2020 et 2024, FAIRCHAIN a réuni 25 partenaires académiques et privés issus de huit pays européens autour d’un objectif commun : développer des chaînes de valeur alimentaires intermédiaires plus compétitives et durables. À partir de cette expérience concrète, la présentation mettra en lumière les dimensions stratégiques du montage d’un projet européen : construction du consortium, définition de l’architecture scientifique, articulation entre co-création et production de connaissances, mise en place des dispositifs de gouvernance, ainsi que certains aspects de suivi administratif et financier. Les principaux défis rencontrés et les enseignements tirés seront discutés dans une perspective réflexive et transférable. Dans le contexte de l’association du Canada au programme Horizon Europe depuis 2024, ce séminaire devrait offrir des repères concrets aux équipes souhaitant s’engager dans ces grands projets collaboratifs en recherche et innovation, en explicitant les attentes, les leviers de réussite et certains points de vigilance.
ano.nymous@ccsd.cnrs.fr.invalid (Geneviève Gésan-Guiziou) 30 Jun 2026
https://hal.inrae.fr/hal-05674135v1
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[hal-05613501] From Concept to Perspective: Digital Twins of Microbial Systems
Digital twins (DTs) are increasingly recognized across diverse sectors for their capacity to enhance the control, efficiency, and comprehension of the physical or biological systems they represent. For microbial systems, DTs could allow model-guided improvements of the services provided by the microbial communities in the agrifood chain. While DTs definitions are generally built on the same core idea of bi-directional exchanges between digital and physical counterparts, where realtime data feeds digital models and model-driven insights guide the real system, a wide variety of definitions of what is a DT still co-exist across domains. This variability underscores the need for a clear, system-specific definition of DTs for microbial ecosystems. In this perspective paper, we propose a conceptual framework for microbial system digital twins (MSDTs), defined as a collection of models dynamically linked to the microbiological system through in-line, at-line or off-line data and control flows. We illustrate this framework with examples spanning environmental, bioprocess, plant, animal, food, and human microbial systems, in a One Health perspective. For each ecosystem, we explore the potential applications of MSDTs. We also identify the scientific challenges that remain in experiments, bioinformatics, data science, modeling, control and microbial ecosystem engineering to build accurate MSDTs. We advocate for the development of MSDT in laboratory settings, as a catalyst for interdisciplinary sciences, and we stress practical and ethical issues preventing the generalization of MSDT for large-scale applications. However, high-tech MSDTs in laboratory environments may pave the way for low-tech, generalizable microbial solutions for improved ecosystemic microbial services.
ano.nymous@ccsd.cnrs.fr.invalid (Simon Labarthe) 06 May 2026
https://hal.inrae.fr/hal-05613501v1
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[hal-05662704] Screening of 103 probiotic and proteolytic bacterial strains for lupin-based food applications targeting allergy modulation
[...]
ano.nymous@ccsd.cnrs.fr.invalid (Ewen Trebossen) 19 Jun 2026
https://hal.inrae.fr/hal-05662704v1
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[hal-05618619] Does bolus structure influence the fate of volatile compounds and nutrients throughout mastication and dynamic digestion in vitro? Case study on a model cheese and its vegetal analogue
<div><p>In the context of sustainable development of agriculture towards improved environment and nutrition, a dietary transition including more plant-based food products is desirable. Yet, this transition is currently slowed by technological, sensorial, or nutritional challenges. To help the design of acceptable plant-based foods, interdisciplinary research projects are required. In this article, we present an integrated approach to study semi-solid plant-based foods from production to in vitro digestion, including the effect of in vitro mastication on volatile compound release as a sensory indicator and on nutrient hydrolysis as a nutrition indicator. To do so, a cow's milk cheese and its vegetal soy-based analogue with matched biochemical composition and texture were developed. A human mastication study was conducted to characterize bolus formation, saliva incorporation, and bolus fragmentation. The results were used to optimize the parameters of a mastication simulator to obtain artificial boluses with similar characteristics as those produced in vivo. To test the effect of bolus particle size distribution, the release of volatile compounds from in vitro masticated boluses was compared to that from boluses produced by strong grinding. Boluses were also subjected to dynamic in vitro gastrointestinal digestion to study the fate of various nutrients including lipid, protein, and vitamin E. Both the food type and the bolus fragmentation degree influenced the results, volatile compound release behavior also depending on the partition coefficient, and gastric digestion kinetics being systematically slower for lipid and protein from strongly ground boluses, attributed to amplified destabilization phenomena of the protein network.</p></div>
ano.nymous@ccsd.cnrs.fr.invalid (Elise Schong) 11 May 2026
https://hal.science/hal-05618619v1
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[hal-05505773] Multivariate Chemometric analysis of chemical diversity in French winter and spring Lupinus albus L. varieties
White lupin (Lupinus albus L.) is a nutrient-rich legume well-adapted to Mediterranean climates and tolerant of abiotic stress. Therefore, lupins represent a sustainable crop option with high potential for use in areas where climate change impacts are intensifying. This study analysed eight cultivars, four winter and four spring ecotypes, to assess differences in nutritional and bioactive compounds. Key compounds studied included proteins, fats, carbohydrates, tocopherols, and phenolics. Spring ecotypes like ‘Sulimo’ and ‘Energy’ showed higher protein and tocopherol content, which may be ideal for protein-rich, antioxidant-rich diets. Winter ecotypes such as ‘Angus’ had more carbohydrates, especially fructose and raffinose, which could benefit energy and gut health. Both ecotypes showed high fibre levels, supporting digestive health. The findings suggest that ecotype influences chemical composition significantly, and each offers distinct benefits for targeted nutritional and functional food applications.
ano.nymous@ccsd.cnrs.fr.invalid (Manuel Ayuso) 11 Feb 2026
https://hal.inrae.fr/hal-05505773v1
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[hal-05645981] Re-exploring the paradigm of dairy fouling mechanisms at the microscopic scale by rheology and microfluidics
The unsolved and costly question of dairy fouling consists in the accumulation of whey proteins and minerals on the equipment walls during heat treatments (e.g., pasteurization, vacuum concentration). The formation of deposits affects process efficiency and promotes the proliferation of biofilms possibly contaminating the products. The solutions adopted in the last decades, based on a process engineering approach, have not proven to be effective mostly due to the lack of real-time observation of fouling development. To date, fouling has been attributed to the thermal denaturation of whey proteins above ≈70 °C, which causes their unfolding, aggregation and adsorption onto surfaces. Yet deposit formation is also observed at temperatures below the denaturation threshold (e.g., in falling film evaporators), challenging this explanation. This has led to renewed interest in investigating the micron-scale mechanisms governing fouling development, with particular focus on the impact of process parameters other than temperature. In this regard, our recent rheofluidic studies showed that shear not only increases the amount of surface deposits at sub-denaturation temperatures, but also fosters their structural complexity. While a transition from globular deposits to branched gel-like structures was observed on the surfaces at increasing concentrations, only submicronic aggregates formed in the sheared protein solutions. The real-time influence of shear on deposit growth was also evaluated using microfluidic devices mimicking process and environmental conditions typical of dairy heat treatments. Our results highlight the combined effects of temperature and shear on fouling development, with interconnected concentration-dependent dynamics occurring in the bulk and at the surface. This miniaturized strategy promotes the elaboration of new predictive models of fouling development and innovative strategies to minimize this phenomenon, potentially adaptable to other biological and industrial systems affected by protein fouling.
ano.nymous@ccsd.cnrs.fr.invalid (M Grostete) 05 Jun 2026
https://hal.inrae.fr/hal-05645981v1
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[hal-05586122] Contrasting fermentation practices and typologies of fermented foods between france and african countries. A cross-cultural perspective from the pimento initiative
A cross-cultural analysis was conducted on fermented foods (FF) produced in France and in two African countries representing Saharan and sub-Saharan regions (Morocco and Senegal). The objectives were to evaluate the different typologies of FF produced in each country, to discuss the different fermentation processes that were used in each country for different categories of investigated FF. By confronting all the data collected, we found a difference in the cultural approaches in FF elaboration and organization. In France, the fermented food sector is notable for its well-structured and diverse range of products produced with commercial starter cultures. Alcoholic fermentation takes an important place in France particularly in fermented beverages and cereal-based FF, whereas in African countries such fermentation is lowly used excepted for some beers. In African countries, the culture of spontaneous fermentation with autochthonous microorganisms, naturally present in milk and fish, dominates the FF products. The fermentation of dairy by-products is widespread, particularly in Morocco, which offers diverse FF products from various animal sources. In Senegal, a traditional food practice involves eating fermented couscous obtained by spontaneous lactic fermentation of cereals. Such comparative study underlines lactic fermentation, especially in dairy FF, as a common feature across cultures. The survey allowed to establish some connections that could help each country in their development and fermentation practices for sustainability, astronomy, economy and preservation of microbial biodiversity through FF interculture.
ano.nymous@ccsd.cnrs.fr.invalid (Christian Coelho) 09 Apr 2026
https://hal.inrae.fr/hal-05586122v1
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[hal-05560441] Le lait, qu’est-ce que c’est ?
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ano.nymous@ccsd.cnrs.fr.invalid (Didier Dupont) 20 Mar 2026
https://hal.science/hal-05560441v1
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[hal-05565935] Criblage de 103 souches bactériennes probiotiques et protéolytiques pour leur potentiel dans la modulation de l’allergénicité du lupin
[...]
ano.nymous@ccsd.cnrs.fr.invalid (Ewen Trebossen) 25 Mar 2026
https://hal.science/hal-05565935v1
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[mnhn-05564131] An updated classification of growth forms in non‐geniculate coralline algae (Corallinophycidae, Rhodophyta)
Abstract The current challenge of defining growth forms in the non‐geniculate coralline red algae was addressed. Since the 19th century, those who have worked on this large and globally distributed group of algae have tried to summarize and systematically describe their growth forms. This effort resulted in a plethora of terms, which could sometimes be confusing, overlapping, and difficult to apply in the field. We reviewed the past literature to provide a coherent key to the non‐geniculate coralline growth forms, incorporating the latest observations. Our revision expands the 10 currently recognized growth forms ( unconsolidated , encrusting , warty , lumpy , fruticose , discoid , layered , foliose , ribbon‐like , and arborescent ) by redefining some of them, by reintroducing the columnar growth form, and by adding two new growth forms— convoluted and imbricate —to include recently documented specimens. This updated and refined tool better encompasses the diverse external morphologies of non‐geniculate corallines. The goal was to facilitate taxonomic descriptions and to support ecological studies of non‐geniculate corallines given the extreme difficulty of identifying species using only external characters.
ano.nymous@ccsd.cnrs.fr.invalid (Gavin Maneveldt) 24 Mar 2026
https://mnhn.hal.science/mnhn-05564131v1
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[inserm-05575125] The short-chain fatty acid butyrate prevents gut-brain amyloid-β pathology and neuroinflammation in an Alzheimer mouse model
Amyloid-β (Aβ) plays a critical role in Alzheimer's disease (AD) and its accumulation in the brain is pivotal to disease progression and precedes memory and neuronal loss. Besides the severely handicapping brain symptoms, AD patients display early gastro-intestinal (GI) manifestations such as upper and lower GI dysmotility, in particular constipation. Although there is increasing evidence of Aβ accumulation in the gut, its pathogenic effects on enteric nervous system (ENS) connectivity and gut function as well as underlying pathophysiological mechanisms are poorly understood. Furthermore, studies have reported a gut to brain transmission of Aβ that causes memory deficits in mice. Therefore, identifying therapeutics which can reduce Aβ accumulation in the gut at an early stage of the disease could have the advantage of slowing or even reversing disease progression before severe alterations or irreversible damages at both intestinal and brain levels. Hence, in this study, we investigated the capacity of the short-fatty acid butyrate to restore Aβ-driven alteration of ENS connectivity and gut-brain functions in the SAMP8 mouse model of AD. Here we show that SAMP8 mice display a gut amyloid pathology, an alteration of ENS connectivity and gut defects prior to memory decline. BACE1, an Aβ-producing enzyme, expression and activity are increased whereas neprilysin, an Aβ-degrading enzyme, is decreased in the gut of SAMP8 mice, indicating a rise in the Amyloid Precursor Protein (APP) holoprotein processing and a reduction of Aβ clearance which promote an amyloidosis. In primary ENS cultures, Aβ causes a degradation of synaptic-associated proteins EphB2 and synaptophysin, leading to an alteration of ENS connectivity. In wild-type mice, intra-colon delivery of Aβ alters ENS connectivity and causes subsequent GI symptoms, recapitulating the phenotype of the SAMP8 mouse model of aging and AD. Moreover, Aβ impairs ENS connectivity in human induced pluripotent stem cell (iPSC)-derived intestinal organoids and explant cultures of human colon, indicating that Aβ causes ENS lesions in models of the human gut. Butyrate, a short-chain fatty acid derived from bacterial metabolism, reduces Aβ secretion and preserves enteric neuronal connectivity in vitro and in vivo, and blocks Aβ accumulation in the gut, brain and plasma in SAMP8 mice. In addition, butyrate ameliorates neuroinflammation and prevents gut dysfunction and memory deficit. Collectively, these findings suggest that Aβ promotes gut symptoms through alteration of ENS connectivity and butyrate counteracts these impairments with an amelioration of neuroinflammation and memory function in AD model.
ano.nymous@ccsd.cnrs.fr.invalid (Rodrigue Brossaud) 01 Apr 2026
https://inserm.hal.science/inserm-05575125v1
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[hal-05565140] Tea, coffee, and cocoa delay milk gastric coagulation in a biomimetic in vitro system (NERDT™) by hindering both acid- and pepsin-induced milk gelation
This study investigated the effect of mixing whole milk with hot water extract of cocoa, coffee, or tea on milk intragastric coagulation during dynamic in vitro digestion. Milk diluted with water in the same proportion (70:30 v/v) was used as the control. The effect of adding cocoa, coffee, or tea extracts on acid-and pepsin-induced milk coagulation was first studied using a rheometer. The control exhibited a significantly shorter (P &lt; 0.0001) gelation time in acidinduced coagulation than the milk mixtures containing extracts. The delaying effect of extracts on pepsin-induced coagulation was even more pronounced with coffee, causing a marked delay in gelation time, while tea and cocoa completely prevented gel formation under our experimental conditions. The milk mixtures, preheated to 60 °C, were then studied during simulated gastric digestion using the NEar Real Digestive Tract (NERDT TM ) dynamic in vitro digestion system. Samples collected at the stomach exit at different time points were investigated for pH, dry matter and microstructure. During gastric digestion of the control, protein coagulation occurred between 5 to 18 min (pH 6.3 ± 0.01 and 5.7 ± 0.28, respectively), whereas in the presence of cocoa, coffee, or tea, milk coagulation was observed between 18 to 27 min (pH 5.6 ± 0.07 and 4.84 ± 0.22 respectively). Confocal micrographs revealed larger protein aggregates in samples containing extracts, with entrapped milk fat clearly visible. The observed effects are likely due to the high polyphenol content of the extracts, which are known to interact with milk proteins. Our findings therefore suggest that protein-polyphenol interactions delay casein coagulation in the stomach and may alter gastric emptying and subsequent nutrient absorption along the small intestine.
ano.nymous@ccsd.cnrs.fr.invalid (Isuri A Jayawardana) 20 Apr 2026
https://institut-agro-rennes-angers.hal.science/hal-05565140v2
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[hal-05566725] Characterization of peptides released from gluten-free climate-smart cowpea-based pasta during gastric and intestinal in vitro digestion
Four nutritionally optimized cowpea-based pasta incorporating or not teff and/or amaranth leaves underwent in vitro static gastro-intestinal digestion using the Infogest model. The aim of this study was to characterize the peptides released at the end of the gastric and intestinal phase of cowpea-based pasta compared to wheat-based pasta controls with an increasing fiber content, using SDS-PAGE and mass spectrometry. At end of intestinal phase, the four cowpea-based pasta presented slightly lower peptides number of similar size compared to wheat-based pasta, which could indicate a lower proteolysis. Additionally, no significant difference in origin of peptide profile was observed with teff or amaranth leaf additions within cowpea-based pasta, nor with the increase of fiber within wheat-based pasta. Peptide released from cowpea-based pasta mainly comes from cowpea proteins, and especially globulins “RmlC-jelly roll fold” and “11S-seed storage protein”. Vigilance is required for these globulin which have putative allergenic epitopes on their sequences.
ano.nymous@ccsd.cnrs.fr.invalid (Pauline Pinel) 25 Mar 2026
https://institut-agro-rennes-angers.hal.science/hal-05566725v1
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[hal-05247019] A digital twin integrating multi-objective optimization to support fryer operators in managing potato crisps production
The production of potato crisps currently relies on the expertise of human operators, known as fryers, whose training is long and demanding. With the decline in fryer vocations and the increase in consumer quality expectations, it is now essential to develop decision-support tools to make fryer work easier and better control product quality. This study proposes a digital twin (DT) approach that incorporates multi-objective optimization to assist fryers in managing their crisp production line. Data from crisp production is collected and used to model key crisp physicochemical indicators (Fat content, Moisture content, and Lightness) using a Machine Learning approach, specifically the Random Forest method. Then, a multi-objective optimization is carried out using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) algorithm, which identifies optimal adjustments to enhance the three crisp physicochemical indicators. The optimization is tested on 2 batches of potatoes as inputs. The algorithm generates a set of optimal solutions, from which a final solution is selected using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) multi-criteria decision-making method. This solution provides practical recommendations for adjusting production parameters according to a given potato batch quality. The results show that physicochemical parameters of the crisps are similar after optimization, regardless of the quality the potato batch. Variation in potato batch quality is compensated by appropriate adjustments of the crisp manufacturing process parameters ensuring consistent and optimal production. In conclusion, this digital twin, integrating multi-objective optimization, proves to be a valuable tool for improving fryer decision-making and optimizing production line management.
ano.nymous@ccsd.cnrs.fr.invalid (Manon Perrignon) 09 Sep 2025
https://hal.science/hal-05247019v1
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[hal-05537904] Isolation, Characterization and Genomic Analysis of PBC_MG88 and PBC_MG99 Bacteriophages and Their Antibiofilm Activity Against the Bacillus cereus Groups
Bacillus cereus is a major foodborne pathogen responsible for food spoilage and foodborne illness, including strains producing emetic toxins. In this study, two bacteriophages, PBC_MG88 and PBC_MG99, were isolated from wastewater using emetic B. cereus strains as hosts and were comprehensively characterized. Both phages formed clear plaques with halos and exhibited siphovirus morphology. Host range analysis against 172 B. cereus strains showed that PBC_MG88 and PBC_MG99 infected 50 and 60 strains, respectively. One-step growth experiments revealed efficient lytic activity, with latent periods of 20-25 min and burst sizes of 59-63 PFU per infected cell. More than 90% of phage particles adsorbed to host cells within 15 min. Both phages were stable across a wide temperature range (4-55 • C) and pH values (4-11). Genome sequencing revealed ~37 kb double-stranded DNA genomes lacking antibiotic resistance or virulence genes; however, the presence of lysogeny-related genes suggests a temperate lifestyle. Comparative genomic analyses indicated that both phages represent novel species within the genus Lwoffvirus. Biofilm assays demonstrated significant inhibition of B. cereus biofilm formation and reduction of pre-established biofilms. Overall, this study expands knowledge of B. cereus phage diversity and highlights the importance of genomic characterization in phage-based biocontrol research.
ano.nymous@ccsd.cnrs.fr.invalid (Maroua Gdoura-Ben Amor) 05 Mar 2026
https://institut-agro-rennes-angers.hal.science/hal-05537904v1
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[hal-05603020] Mechanical instabilities in drying protein droplets under substrate-free conditions
<div><p>Understanding how proteins of different origins behave during drying is essential for controlling the mechanical stability and final structure of protein-based materials. Here, we examine the drying dynamics of acoustically levitated droplets containing either napin, a plant-derived seed storage protein, or native phosphocaseinate, a dairy protein complex, to uncover how their intrinsic physicochemical and mechanical properties govern evaporation-driven instabilities. Compared to sessile droplets, levitated droplets dry under symmetric evaporation conditions, minimizing substrate effects and contact-line pinning. During drying, both systems develop a solid skin at the air-liquid interface, which undergoes mechanical buckling once compressive stresses exceed the skin's rigidity. Despite similar overall drying kinetics, differences emerge between the two protein systems: native phosphocaseinate droplets form ductile, crack-free shells, whereas napin droplets display brittle fracture and surface cracking. These contrasting behaviours reflect fundamental differences between plant and animal proteins in terms of interfacial activity and network formation. The results are further supported by comparison with model colloid-polymer films, establishing a direct link between interfacial mechanics, crack formation, and film ductility. By revealing how protein origin governs drying-induced instabilities, this work provides mechanistic insight into the design of protein-based materials and supports the development of sustainable, plant-derived protein alternatives for food, pharmaceutical, and soft-material applications.</p></div>
ano.nymous@ccsd.cnrs.fr.invalid (Ludovic Pauchard) 27 Apr 2026
https://hal.science/hal-05603020v1
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[hal-05495400] Exploring the Relationship Between Astringency and Lingual Tactile Sensitivity
When lingual tactile sensitivity has received less attention than taste, it plays a critical role in food textural preferences and eating behavior. The anterior tongue, rich in specialized mechanoreceptors, is particularly sensitive to tactile stimuli. This study investigated inter‐individual variability in lingual tactile sensitivity and its potential relationship with astringency sensitivity. To this end, three distinct aspects of lingual tactile sensitivity as well as tongue strength were assessed in 39 subjects (26 F, mean age = 35 ± 5 years). The three tactile dimensions included: (i) light touch (assessed with Von Frey monofilaments in a one‐point pressure test), (ii) spatial perception (two‐point discrimination test), and (iii) roughness sensitivity (using paper coupons with varying grit sizes). Astringency detection thresholds, previously determined using tannic acid solutions, were available for all participants. Results revealed significant inter‐individual variability across all tactile measures. Notably, no significant correlations were found between the three different tactile sensitivity tests (light touch, spatial perception, roughness), suggesting that each one captures a distinct aspect of lingual tactile functions. Tongue strength was not associated with either tactile or astringency sensitivity. A key finding was a significant positive correlation between the tannic acid astringency detection threshold and the pressure discrimination threshold, suggesting that astringency sensitivity may involve a tactile component possibly mediated by the slowly adapting mechanoreceptors (SAI and SAII types). However, no relationship was found between astringency sensitivity and roughness sensitivity. The study emphasizes the need for standardized methods to better understand distinct dimensions of lingual tactile sensitivity and their influence on food texture perception.
ano.nymous@ccsd.cnrs.fr.invalid (Anaïs Lavoisier) 10 Feb 2026
https://hal.science/hal-05495400v1
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[hal-05560446] INFOGEST Quant: standardized in vitro determination of digestibility and DIAAS of dietary proteins based on the INFOGEST static digestion model
This protocol describes a standardized in vitro method to determine the digestibility and digestible indispensable amino acid score (DIAAS) of dietary proteins. This 'INFOGEST Quant' method is an extension of our previous INFOGEST static digestion model (INFOGEST 2.0) and adds a workflow for the quantification of total protein digestibility, individual amino acid digestibility and DIAAS. The protocol was validated using in vivo data obtained by digesting the same food samples, and the results showed a high degree of agreement, confirming its relevance for nutritional assessments. To establish the DIAAS of a protein source, nonabsorbable peptides and proteins are precipitated after in vitro digestion and the resulting absorbable fraction is analyzed using ultrahigh-performance liquid chromatography with ultraviolet detection (to assess total and individual amino acids). Two alternative quantification strategies are also described: protein titration using the Kjeldahl method (to assess total nitrogen) and spectrophotometric analysis with o-phthalaldehyde (to assess total amino groups). Both alternative methods are valid only for the calculation of total digestibility and the proxy-digestible indispensable amino acid ratio, which gives an approximation of the DIAAS of the tested protein sources. Compared to existing approaches, this protocol is suitable for routine application in nutrition and food science laboratories. The preparatory steps take similar to 6 d, whereas the full workflow can be completed in triplicate in similar to 8 d. Analysis of the digesta takes an additional 3-5 d, depending on the method. The procedure requires only standard laboratory equipment and reagents and can be performed by anyone with basic training in biochemistry or a related discipline.
ano.nymous@ccsd.cnrs.fr.invalid (Lotti Egger) 20 Mar 2026
https://hal.science/hal-05560446v1
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[hal-05491106] Which factors impact calcium bioaccessibility in dairy and plant-based products during static in vitro digestion?
Calcium deficiency is widespread worldwide. In western countries, the main source of dietary calcium are dairy products, although some plant foods can also contribute. This work aimed to determine the solubility and the bioaccessibility of calcium from various food sources and to investigate how food components impact these two properties. A static in vitro gastrointestinal digestion model (INFOGEST) was used for two types of samples: (1) model solutions consisting in calcium solutions to which a compound present in dairy or plant products presumed to interact with calcium was added and (2) plant and dairy products. Calcium bioaccessibility was determined by measuring the soluble calcium concentration relative to total calcium concentration in the samples. The soluble calcium content was measured at different times during gastric and intestinal digestion using inductively coupled plasma-optical emission spectrometry. In vitro digestion indicated that the low pH during the gastric phase promoted the calcium solubilization. During the intestinal phase, however, calcium solubility decreased due to the pH increase to about 7. Phosphate, palmitic acid, micellar casein and phytate appear to interact with calcium, decreasing its solubility in the intestinal phase, probably through the formation of insoluble complexes. The calcium bioaccessibility of dairy matrices (yogurt, cheese, milk) was particularly high (between 19 and 34 %). However, calcium bioaccessibility was more disparate for plant-based dairy alternatives (between 5 and 20 %) and whole plant foods (between 1 and 27 %). In terms of the quantity of bioaccessible calcium per serving, dairy products (yogurt, cheese, milk) were the best sources.
ano.nymous@ccsd.cnrs.fr.invalid (Rozenn Le Foll) 03 Feb 2026
https://hal.inrae.fr/hal-05491106v1
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[hal-05560455] Will climate change affect nutrient, micronutrient and bioactive bioavailability?
Climate change is projected to profoundly affect global food systems, directly altering food availability and composition and, as a result, nutritional outcomes. Modifications to the composition and properties of food matrices may, in turn, influence the digestion, absorption, and metabolism of food compounds. This can lead to changes in the bioavailability of macronutrients, micronutrients, and bioactive compounds. Additionally, strategies implemented to mitigate climate change, such as transitioning to green food processing methods or modifying diets, may also affect the content and bioavailability of (micro)nutrients in foods.In this review, we will discuss, for the first time, the direct and indirect relationships between climate change and the bioavailability of selected food compounds: proteins, fat-soluble micronutrients, minerals, phenolic compounds, and glucosinolates.
ano.nymous@ccsd.cnrs.fr.invalid (Emmanuelle Reboul) 20 Mar 2026
https://hal.science/hal-05560455v1
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[hal-05507613] Contribution of grape-associated fungal species to the FMA defect on grapes and in musts
Among reported wine defects, the fresh mushroom aroma (FMA) off-odor has been linked to fungal volatile compounds (VOCs). However, the fungi causing this defect and the associated VOCs have not been fully elucidated, except for some reported FMA markers. Also, the biotic and abiotic factors impacting fungal growth and FMA production are poorly understood. Here, using a multidisciplinary approach combining predictive and classical mycology, sensorial and biochemical analyses, we determined growth patterns and VOCs profiles for 18 grape-associated fungal isolates, individually or in co-inoculation, on must media or Meunier grapes. FMA was primarily linked to Penicillium species, especially Penicillium crocicola with high intensity. On grapes, Botrytis cinerea co-inoculations with Penicillium bialowiezense or Penicllium citreonigrum led to detectable FMA off-odors and an increase in 3-octanol and 3-octanone FMA markers. Penicillium species competitively grew with Botrytis on grapes in comparison to other fungi, often leading to higher FMA perception. Fungal growth kinetics on must-based media were determined, and fastest growth rates were observed for Botrytis cinerea and Penicillium crocicola isolates although most fungi were able to grow in a wide range of conditions. Overall, our results pinpointed which individual and co-inoculated grape-associated fungi thrived on berries and in must conditions, and which combinations favored FMA off-odor production. This data can be used for better vineyard management practices and to anticipate potential conditions leading to FMA emergence in the future and in link with climate change and develop predictive tools for better vineyard management.
ano.nymous@ccsd.cnrs.fr.invalid (Adrien Destanque) 12 Feb 2026
https://hal.inrae.fr/hal-05507613v1
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[hal-05593019] Bacterial cell envelope components of gut commensals: effects in host-microbe interaction
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ano.nymous@ccsd.cnrs.fr.invalid (Thaís Vilela Rodrigues) 15 Apr 2026
https://hal.science/hal-05593019v1
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[hal-05488556] Dry-Heating-Induced Microparticles of β-Lactoglobulin: Understanding the Respective Role of Alkaline pH and Lactose
When whey proteins are stored in solution at 4 °C and pH 9.5 in the presence of lactose and then dried, dry-heating (DH) of the powder at 100 °C leads to the formation of protein–protein cross-link within the powder particles. Suspensions of the dry-heated powder consist of microparticles with sizes similar to those of the original powder grains, which entrap large amounts of water for functional purposes. In this work, the denaturation and aggregation of pure β-lactoglobulin (β-Lg) and the yield of its conversion into microparticles were characterized at different stages of the process under different conditions (pH, presence of lactose, sucrose, and ammonium chloride) to gain insight into the mechanism of microparticle formation. Qualitatively, only limited changes in the secondary structure of β-Lg were shown during storage of β-Lg solution at pH 6.5 and 9.5. However, increased denaturation and aggregation with prolonged storage at pH 9.5 promoted microparticle formation. β-Lg aggregates formed during storage at pH 9.5 were precursors for their DH-induced cross-linking into microparticles in the presence of Maillard reaction products.
ano.nymous@ccsd.cnrs.fr.invalid (Marie-Hélène Famelart) 02 Feb 2026
https://institut-agro-rennes-angers.hal.science/hal-05488556v1
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[hal-05591254] Production d’EPS par les bactéries lactiques : diversité et applications industrielles
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ano.nymous@ccsd.cnrs.fr.invalid (Stéphanie-Marie Deutsch) 14 Apr 2026
https://hal.inrae.fr/hal-05591254v1
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[hal-05658724] Low-energy fava been extrusion: balancing functional and nutritional properties
<div>V alorisation<p>Transfert de savoir-faire technologique sur les paramètres optimaux du procédé d'extrusion vers le partenaire industriel VALOREX, en vue du développement d'une nouvelle ligne de production et de nouveaux ingrédients commercialisables. Extrusion de la féverole à basse énergie : concilier qualités fonctionnelles et nutritionnelles 5-Formulation et structuration d'aliments et ingrédients</p></div>
ano.nymous@ccsd.cnrs.fr.invalid (Didier Dupont) 16 Jun 2026
https://hal.inrae.fr/hal-05658724v1
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[hal-05542659] Letter : A synthetic bacterial community made of human milk isolated strains is an effective strategy to prevent food allergy in a mouse model
No abstract available
ano.nymous@ccsd.cnrs.fr.invalid (Barbara Misme-Aucouturier) 09 Mar 2026
https://hal.inrae.fr/hal-05542659v1
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[hal-05558939] Nutrition and health aspects of milk and milk products
The present chapter aims to give an overview of the worldwide dairy products and of their nutritional quality. The importance of their food structure on digestion is examined, before reporting their health properties, as indicated by meta-analyses of epidemiological studies. Dairy products, mainly originating from bovine milk, are a good source of high-quality proteins, specific lipids (polar, short chain, conjugated), micronutrients (calcium, iodine, phosphorus, vitamins B2 and B12, etc.), and eventually of probiotics and their deriving metabolites. The dairy product structure affects the protein and lipid digestion fate, with potential metabolic consequences. Dairy products appear to have health effects either beneficial (obesity, type II diabetes, hip fracture) or neutral (cardiovascular diseases), but may be at risk for prostate cancer for high consumers. Overall, dairy products are an important food group, supplying essential nutrients and eventually probiotics, with potential beneficial health effects as long as consumed at the recommended levels (2–3 portions/day).
ano.nymous@ccsd.cnrs.fr.invalid (Amélie Deglaire) 19 Mar 2026
https://institut-agro-rennes-angers.hal.science/hal-05558939v1
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[hal-05582115] Human milk bacteria assembled into functionally distinct synthetic communities in infant formula differently affect intestinal physiology and microbiota in neonatal mini-piglets
The contribution of human milk (HM) microbiota to infant gut health was addressed by evaluating the impact of HM bacteria, combined in two synthetic communities (SynComs) exhibiting anti-inflammatory (AI) or high immunomodulatory (HI) properties in vitro , on gut immune and barrier functions, and microbiota. Neonatal mini-piglets were fed either a formula without supplementation (CTRL) or supplemented with AI or HI SynComs and were compared to sow milk-fed (SM) piglets over a period of 24 days. Feces were collected on postnatal day (PND) 8, and ileal, colonic, and fecal samples were collected on PND24. The multifactorial analysis indicated that the two HM-derived SynComs impacted microbiota and intestinal functions differently. Several genera, mainly belonging to Bacillota, displayed different relative abundances between the formula-fed groups at both PND8 and PND24. At PND8, the fecal secretory IgA (sIgA) level in HI piglets was slightly lower than in SM piglets but markedly higher than in CTRL and AI piglets. SynComs HI and/or AI slightly increased the expression of genes involved in pro-inflammatory (IL6, TNFaR1), antioxidant (SOD2), anti-inflammatory (SOCS3), and Treg (FOXP3) pathways in ileal and colonic tissues compared with the CTRL group. Systemic immune functions were also modulated with a cytokine secretion capacity of peripheral blood mononuclear cells that tended to be higher with HI supplementation. Interestingly, SynCom bacteria were correlated with several ileal and colonic genera, and both were correlated with physiological variables. Overall, our findings support the influence of HM bacteria, provided in formulas as SynCom at a physiological concentration, on gut microbiota and functions. IMPORTANCE Early-life environmental factors, such as neonatal diet, influence the gut microbiota, which plays a key role in the functional development of the gut. However, the role of the human milk (HM) microbiota, particularly with regard to the immunomodulatory properties of HM bacteria, is not well understood. This study investigates the differential effects of two synthetic communities with a similar taxonomic composition representative of the taxonomic diversity of the HM microbiota. These communities exhibit contrasting immunomodulatory properties that were previously characterized using an in vitro intestinal quadricellular model. Daily supplementation with these two SynComs modulated the composition of the gut microbiota and the gut physiology differently, particularly the intestinal immune signatures. In conclusion, the functional profile of bacteria within the HM microbiota may induce distinct developmental profiles of gut physiology in infants.
ano.nymous@ccsd.cnrs.fr.invalid (Charles Le Bras) 05 May 2026
https://hal.inrae.fr/hal-05582115v1
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[hal-05574658] Local environmental drivers override cascade effects on phytoplankton and periphyton along a dammed river continuum
River damming alters hydrology, light availability and nutrient dynamics, thereby reshaping both pelagic and benthic primary producers. In double-dam systems, it remains unclear whether the two structures function as a single unit (“double-dam effect”) or whether the downstream dam adds cumulative impacts (“cascade effect”). Over two hydrological years, we investigated the responses of phytoplankton and periphyton to cascading dams, along the Sélune River (France), focusing on photosynthetic activity, biomass and assemblage. Using multivariate analyses, we quantified the relative influence of local environmental and climatic conditions (light, temperature, turbidity, nutrient concentrations and stoichiometry, conductivity, pH, dissolved oxygen, rainfall), spatial position along the river continuum, habitat type (lotic vs. lentic), and season on both communities. Local environmental factors explained most of variance in phytoplankton and periphyton, with light availability, temperature, and nutrient stoichiometry (TDN:TDP) as the dominant drivers. By explicitly testing cascade versus double-dam effects through comparisons of biological variables (activity, biomass and species abundances) between dams and with the downstream lotic station, we found evidence for a single-dam effect for both phytoplankton and periphyton. This pattern likely reflects short water residence times, which constrain the development of cumulative impacts along the dam cascade.
ano.nymous@ccsd.cnrs.fr.invalid (Alexandrine Pannard) 31 Mar 2026
https://hal.science/hal-05574658v1
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[hal-05620760] Genome-guided antimicrobial potential of Bacillus stercoris from coastal sand with activity against multidrug-resistant bacteria, including MRSA
Coastal beach environments harbor diverse bacterial communities, yet their antimicrobial potential remains largely unexplored. This study evaluates the antimicrobial potential of a bacterial isolate 2AT10 from Brazilian beach sand through in vitro, in silico, and ex vivo assays. Isolate 2AT10, a rod-shaped Gram-positive bacterium, exhibited broad-spectrum antimicrobial activity, with its culture supernatants showing greater efficacy against Gram-positive bacteria, including multidrug-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA). Antimicrobial activity from two differently processed supernatants decreased after heat treatment, enzymatic digestion, and pH changes, suggesting similar proteolytic profiles. Fourier-transform infrared spectroscopy (FTIR) revealed peaks corresponding to C = O and NO₂ groups, indicating the presence of amide functional groups. Importantly, the supernatants did not cause irritation in the ex vivo chorioallantoic membrane assay. Genomic analysis identified isolate 2AT10 as Bacillus stercoris, harboring genes encoding subtilosin A, bacilysin, bacillibactin, bacillaene and lactococcin-like bacteriocins, all associated with antimicrobial activity. A mutation in the sboA gene, involved in subtilosin A biosynthesis and previously linked to in vitro hemolytic activity and enhanced activity against Gram-positive bacteria, was also detected. Molecular docking and dynamics analyses suggested a possible interaction between lactococcin-like bacteriocin and a membrane component of the S. aureus phosphotransferase system transporter, possibly increasing membrane permeability.
ano.nymous@ccsd.cnrs.fr.invalid (Camilla Andrade Silva Valença) 12 May 2026
https://hal.science/hal-05620760v1