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The study aimed to assess the extent to which protein aggregation, and even the modality of aggregation, can affect gastric digestion, down to the nature of the hydrolyzed peptide bonds. By controlling pH and ionic strength during heating, linear or spherical ovalbumin (OVA) aggregates were prepared, then digested with pepsin. Statistical analysis characterized the peptide bonds specifically hydrolyzed versus those not hydrolyzed for a given condition, based on a detailed description of all these bonds. Aggregation limits pepsin access to buried regions of native OVA, but some cleavage sites specific to aggregates reflect specific hydrolysis pathways due to the denaturation-aggregation process. Cleavage sites specific to linear aggregates indicate greater denaturation compared to spherical aggregates, consistent with theoretical models of heat-induced aggregation of OVA. Thus, the peptides released during the gastric phase may vary depending on the aggregation modality. Precisely tuned aggregation may therefore allow subtle control of the digestion process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Introduction: Rapidly progressive necrotising soft tissue infections (NSTIs) are associated with high mortality and morbidity. Low incidence and disease heterogeneity contribute to low event rates and inadequately powered studies. The Necrotising Infections Clinical Composite Endpoint (NICCE) provides a binary outcome with which to assess interventions for NSTIs. Partly with a view towards studies of hyperbaric oxygen treatment in NSTIs we aimed to validate NICCE in a retrospective cohort of NSTI patients., Methods: Eligible patients were admitted between 2012 and 2021 to an adult major referral hospital in Victoria, Australia with surgically confirmed NSTI. The NICCE and its constituents were assessed in the whole cohort (n = 235). The cohort was divided into two groups using the modified sequential organ failure assessment (mSOFA) score, with an admission mSOFA score ≥ 3 defined as high acuity., Results: Baseline characteristics of the whole (n = 235), the high (n = 188) and the low acuity cohorts (n = 47) were similar. Survival rates were high (91.1%). Patients with an admission mSOFA ≥ 3 were less likely to meet NICCE criteria for 'success' compared to the lower acuity cohort (34.1% and 64.7% respectively). Meeting NICCE criteria was significantly associated with lower resource utilisation, measured by intensive care unit days, ventilator days, and hospital length of stay for all patients and for those with high acuity on presentation., Conclusions: The NICCE provides greater discriminative ability than mortality alone. It accurately selects patients at high risk of adverse outcomes, thereby enhancing feasibility of trials. Adaptation of NICCE to include patient-centred outcomes could strengthen its clinical relevance., Competing Interests: The authors report no conflicts of interest in this work., (Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.)

Fortification of human milk (HM) is often necessary to meet the nutritional requirements of preterm infants. The present experiment aimed to establish whether the supplementation of HM with either an experimental donkey milk-derived fortifier containing whole donkey milk proteins, or with a commercial bovine milk-derived fortifier containing hydrolyzed bovine whey proteins, affects peptide release differently during digestion. The experiment was conducted using an in vitro dynamic system designed to simulate the preterm infant's digestion followed by digesta analysis by means of LC-MS-MS. The different fortifiers did not appear to influence the cumulative intensity of HM peptides. Fortification had a differential impact on the release of either donkey or bovine bioactive peptides. Donkey milk peptides showed antioxidant/ACE inhibitory activities, while bovine peptides showed opioid, dipeptil- and propyl endo- peptidase inhibitory and antimicrobial activity. A slight delay in peptide release from human lactoferrin and α-lactalbumin was observed when HM was supplemented with donkey milk-derived fortifier., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Laura Cavallarin has patent #Food Composition - EP 3057450 B1 issued to n.a. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Ménière's disease is a disabling condition causing vertigo and hearing loss yet remains incompletely understood. Registry studies have the potential to answer important questions about phenotypes and natural history of clinical conditions. The aim of this study was to explore the feasibility of a patient-centered national Ménière's disease registry. This was an observational study carried out at 4 state-funded hospitals and 4 independent clinics, within 3 distinct urban and rural regions within the UK. Adults with Ménière's disease were eligible to participate. A range of patient reported data, questionnaire data and clinical data (audiometric, radiological, and specialist balance testing data) was inputted into a bespoke database. The study recruited 411 participants. The majority of participants chose online recruitment (73%) and 27% chose via paper-based methods for participation. A small majority (57%) of participants were female. 96% of participants were of white ethnicity. Data completeness from online or postal data collection was similar. Around 20% of participants had audiological evidence of bilateral Ménière's disease. This feasibility study has successfully piloted methods for recruitment of hundreds of participants diagnosed with Ménière's disease. Participants actively contributed their data to a robust and extensive data collection platform. The positive outcomes from this initial feasibility study are anticipated to serve as a foundation for the future expansion of the registry. This expansion holds the potential to address a broad spectrum of request, encompassing all aspects of the nature of Ménière's disease.

Background: Sepsis is a life-threatening condition which may arise from infection in any organ system and requires early recognition and management. Healthcare professionals working in any specialty may need to manage patients with sepsis. Educating medical students about this condition may be an effective way to ensure all future doctors have sufficient ability to diagnose and treat septic patients. However, there is currently no consensus on what competencies medical students should achieve regarding sepsis recognition and treatment. This study aims to outline what sepsis-related competencies medical students should achieve by the end of their medical student training in both high or upper-middle incomes countries/regions and in low or lower-middle income countries/regions., Methods: Two separate panels from high or upper-middle income and low or lower-middle income countries/regions participated in a Delphi method to suggest and rank sepsis competencies for medical students. Each panel consisted of 13-18 key stakeholders of medical education and doctors in specialties where sepsis is a common problem (both specialists and trainees). Panelists came from all continents, except Antarctica., Results: The panels reached consensus on 38 essential sepsis competencies in low or lower-middle income countries/regions and 33 in high or upper-middle incomes countries/regions. These include competencies such as definition of sepsis and septic shock and urgency of antibiotic treatment. In the low or lower-middle income countries/regions group, consensus was also achieved for competencies ranked as very important, and was achieved in 4/5 competencies rated as moderately important. In the high or upper-middle incomes countries/regions group, consensus was achieved in 41/57 competencies rated as very important but only 6/11 competencies rated as moderately important., Conclusion: Medical schools should consider developing curricula to address essential competencies, as a minimum, but also consider addressing competencies rated as very or moderately important., (© 2024. The Author(s).)

Background: Influenza (flu) vaccination rates in UK care home staff are extremely low. Less than 40% of staff in care homes are vaccinated for influenza (flu), presenting risks to the health of frail residents and potential staff absence from cross-infection. Staff often do not perceive a need for vaccination and are unaware they are entitled to free flu vaccination. The FluCare study, a cluster randomised control trial (RCT), uses behavioural interventions to address barriers. Videos, posters, and leaflets are intended to raise awareness of flu vaccination benefits and debunk myths. On-site staff vaccination clinics increase accessibility. Financial incentives to care homes for improved vaccination rates and regular monitoring influence the environment. This paper outlines the planned process evaluation which will describe the intervention's mechanisms of action, explain any changes in outcomes, identify local adaptations, and inform design of the implementation phase., Methods/design: A mixed method process evaluation to inform the interpretation of trial findings., Objectives: • Describe the intervention as delivered in terms of dose and fidelity, including adaptations and variations across care homes. • Explore the effects of individual intervention components on primary outcomes. • Investigate the mechanisms of impact. • Describe the perceived effectiveness of relevant intervention components (including videos, leaflets, posters, and flu clinics) from participant perspectives (care home manager, care home staff, flu clinic providers). • Describe the characteristics of care homes and participants to assess reach. A purposive sample of twenty care homes (ten in the intervention arm, ten in the control arm) for inclusion in the process evaluation. Data will include (1) study records including care home site profiles, (2) responses to a mechanism of action questionnaire, and (3) semi-structured interviews with care home staff and clinic providers. Quantitative data will be descriptively reported. Interview data will be thematically analysed and then categories mapped to the Theoretical Domains Framework., Discussion: Adopting this systematic and comprehensive process evaluation approach will help ensure data is captured on all aspects of the trial, enabling a full understanding of the intervention implementation and RCT findings., Trial Registration: ISRCTN ISRCTN22729870. Registered on 24 August 2022., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Mass spectrometry has become the technique of choice for the assessment of a high variety of molecules in complex food matrices. It is best suited for monitoring the evolution of digestive processes in vivo and in vitro. However, considering the variety of equipment available in different laboratories and the diversity of sample preparation methods, instrumental settings for data acquisition, statistical evaluations, and interpretations of results, it is difficult to predict a priori the ideal parameters for optimal results. The present work addressed this uncertainty by executing an inter-laboratory study with samples collected during in vitro digestion and presenting an overview of the state-of-the-art mass spectrometry applications and analytical capabilities available for studying food digestion. Three representative high-protein foods - skim milk powder (SMP), cooked chicken breast and tofu - were digested according to the static INFOGEST protocol with sample collection at five different time points during gastric and intestinal digestion. Ten laboratories analysed all digesta with their in-house equipment and applying theirconventional workflow. The compiled results demonstrate in general, that soy proteins had a slower gastric digestion and the presence of longer peptide sequences in the intestinal phase compared to SMP or chicken proteins, suggesting a higher resistance to the digestion of soy proteins. Differences in results among the various laboratories were attributed more to the peptide selection criteria than to the individual analytical platforms. Overall, the combination of mass spectrometry techniques with suitable methodological and statistical approaches is adequate for contributing to the characterisation of the recently defined digestome., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Bacterial extracellular vesicles (EVs) are natural lipidic nanoparticles implicated in intercellular communication. Although EV research focused mainly on pathogens, the interest in probiotic-derived EVs is now rising. One example is Propionibacterium freudenreichii , which produces EVs with anti-inflammatory effects on human epithelial cells. Our previous study with P. freudenreichii showed that EVs purified by size exclusion chromatography (SEC) displayed variations in protein content according to bacterial growth conditions. Considering these content variations, we hypothesized that a comparative proteomic analysis of EVs recovered in different conditions would elucidate whether a representative vesicular proteome existed, possibly providing a robust proteome dataset for further analysis. Therefore, P. freudenreichii was grown in two culture media, and EVs were purified by sucrose density gradient ultracentrifugation (UC). Microscopic and size characterization confirmed EV purification, while shotgun proteomics unveiled that they carried a diverse set of proteins. A comparative analysis of the protein content of UC- and SEC-derived EVs, isolated from cultures either in UF (cow milk ultrafiltrate medium) or YEL (laboratory yeast extract lactate medium), showed that EVs from all these conditions shared 308 proteins. This EV core proteome was notably enriched in proteins related to immunomodulation. Moreover, it showed distinctive features, including highly interacting proteins, compositional biases for some specific amino acids, and other biochemical parameters. Overall, this work broadens the toolset for the purification of P. freudenreichii -derived EVs, identifies a representative vesicular proteome, and enumerates conserved features in vesicular proteins. These results hold the potential for providing candidate biomarkers of purification quality, and insights into the mechanisms of EV biogenesis and cargo sorting., (© The Author(s) 2023. Published by Oxford University Press on behalf of FEMS.)

The care home staff influenza vaccination rate in England is significantly lower than the 75% World Health Organisation recommendation. This represents a substantial potential for resident harm. Barriers to staff vaccination stem from individual and organisational levels. Existing interventions address some but not all barriers and are not underpinned by behavioural science theory. This study aims to estimate the effectiveness and cost-effectiveness of a theory-informed intervention to improve care home staff vaccination rates compared to routine practice.Set in care homes with both nursing and residential focus, and a range of ownership status, only homes providing long stay care to older people with a staff vaccination rate below 40% are eligible to participate. Participation expressions of interest will be sought using a variety of approaches prior to seeking consent.The primary outcome measure is the proportion of staff vaccinated at 6 months, with secondary outcome measures being proportion vaccinated at 3 months, numbers of staff sick days, general practitioner and nurse visits to care home, care home resident hospitalisations and mortality.Based on the assumptions that the mean cluster (care home) size is 54 staff, a coefficient of variation of 0.48, control vaccination rate is 55%, intervention 75%, intra-cluster correlation coefficient of 0.2 and with 90% power, and 20% attrition, we require 39 care homes per arm.Blocked randomisation will be at the level of care home, stratified by the proportion of non-white care home staff, and implemented by Norwich Clinical Trials Unit.The intervention comprises co-designed information videos and posters, provision of in-house staff vaccination clinics, and incentive scheme and monthly data collection on trial outcomes. Beyond usual practice, the control arm will additionally contribute monthly data.Data will be collected at the start, monthly and at 6 months, and analysis will be blind to allocation. Statistical analysis will use the intention-to-treat principle with the difference in vaccination rates between groups compared using a random effect logistic regression model at the staff-level.This will be the first study to use a theory-informed intervention designed to comprehensively address identified barriers to care home staff influenza vaccination.Trial registration: ISRCTN ISRCTN22729870 . Registered on 24 August 22. Secondary identifiers: R209939, IRAS 316820, CPMS 53812., (© 2022. The Author(s).)

This study compared the bioaccessibility of docosahexaenoic acid (DHA) provided encapsulated or unencapsulated within a food matrix. DHA oil was composed of DHA-enriched triacylglycerols prepared as Pickering emulsion by encapsulation with heat-denatured whey protein isolate particles and then incorporated into homogenized liquid egg to get omelets. The effect of encapsulation was analyzed by using a static in vitro digestion model of the adult, which digestive fluid enzymes have also been characterized by proteomics. First, the size of lipid droplets was shown to be smaller and uniformly dispersed in omelets with encapsulated-DHA oil compared to non-encapsulated-DHA oil. Distribution of droplets was more regular with encapsulated-DHA oil as well. As a consequence, we showed that encapsulating DHA oil promoted the hydrolysis by pancreatic lipase during the intestinal phase. A larger proportion of DHA enriched-triacylglycerols was hydrolyzed after two hours of digestion, leading to a greater release in free DHA. Thus, only 32% of DHA remained esterified in the triacylglycerols with encapsulated-DHA oil, compared to 43% with non-encapsulated-DHA oil. The DHA in free form ultimately represented 52% of the total DHA with encapsulated-DHA oil, compared to 40% with non-encapsulated-DHA oil. Finally, our results showed that as much DHA was released after one hour of intestinal digestion when the DHA oil was encapsulated as after two hours when the DHA oil was not encapsulated. Therefore, DHA bioaccessibility was significantly improved by encapsulation of DHA oil in omelets., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The article presents a proteomic dataset generated by a comparative analysis, using gel-free nanoLC-MS/MS, of the cellular proteome of Lactobacillus delbrueckii subsp. bulgaricus , a yogurt starter, when cultivated in soy milk versus in cow milk. The CIRM-BIA1592 strain was cultivated in the aqueous phase of soy milk, or of cow milk. Whole-cell proteins were extracted, trypsinolyzed and analyzed by nano LC-MS/MS, prior to identification and to classification by function using the X!Tandem pipeline software and the proteomic data from NCBI.nlm.nigh.gov. Quantification of the proteins was moreover performed to evidence changes in their expression, depending on the culture medium. Data are available via ProteomeXchange with the identifier PXD033905 (http://www.proteomexchange.org/). This article is related to the research article entitled "The stressing life of Lactobacillus delbrueckii subsp. bulgaricus in soy milk", by G.Jan et al. in Food Microbiology, 2022. This proteomic differential analysis indeed revealed major modulation of the stress proteome, with many stress proteins upregulated in the soy environment., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Published by Elsevier Inc.)

Staphylococcus aureus , a major opportunistic pathogen in humans, produces extracellular vesicles (EVs) that are involved in cellular communication, the delivery of virulence factors, and modulation of the host immune system response. However, to date, the impact of culture conditions on the physicochemical and functional properties of S. aureus EVs is still largely unexplored. Here, we use a proteomic approach to provide a complete protein characterization of S. aureus HG003, a NCTC8325 derivative strain and its derived EVs under four growth conditions: early- and late-stationary growth phases, and in the absence and presence of a sub-inhibitory concentration of vancomycin. The HG003 EV protein composition in terms of subcellular localization, COG and KEGG categories, as well as their relative abundance are modulated by the environment and differs from that of whole-cell (WC). Moreover, the environmental conditions that were tested had a more pronounced impact on the EV protein composition when compared to the WC, supporting the existence of mechanisms for the selective packing of EV cargo. This study provides the first general picture of the impact of different growth conditions in the proteome of S. aureus EVs and its producing-cells and paves the way for future studies to understand better S. aureus EV production, composition, and roles.

Lactobacillus delbrueckii subsp. bulgaricus is a beneficial lactic acid bacterium and constitutes one of the most used, and thus consumed, dairy starters, worldwide. This homofermentative bacterium was the first lactobacillus described and is involved in the fermentation of yogurt and of diverse other fermented products, including cheeses. It has a long history of safe use, as well as documented probiotic lato sensu effects, including alleviation of lactose intolerance. Plant-based fermented products presently experience a considerable development, as a result of evolution of consumers' habits, in a general context of food transition. This requires research and development, and thus scientific knowledge, to allow such transition, including the development of fermented soy milks. These last indeed offer an alternative source of live and active bacteria. The yogurt starters L. delbrueckii subsp. bulgaricus, together with Streptococcus thermophilus, have been implemented to generate yogurt-type fermented soy milks worldwide. While the adaptation of these starters to the dairy environment has been extensively studied, little is known about L. delbrueckii adaptation to the soy environment. We therefore investigated its adaptation to soy milk and compared it to cow's milk. Surprisingly, it did not grow in soy milk, neither alone, nor in co-culture with S. thermophilus. Acidification of soy milk was however faster in the presence of both species. In order to deepen such adaptation, we then compared L. delbrueckii growth and survival in soy milk ultrafiltrate (SUF, the aqueous phase of soy milk) and compared it to cow's milk ultrafiltrate (MUF, the aqueous phase of cow milk). This comparison revealed major differences in terms of cell morphology and proteome composition. Lactobacilli appeared deformed and segmented in soy. Major differences in both the surface and the cellular proteome indicated upregulation of stress proteins, yet downregulation of cell cycle and division machinery. Altogether, these results suggest that soy milk may be a stressing environment for the yogurt starter L. delbrueckii subsp. bulgaricus., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Reducing salt intake can mitigate the prevalence of metabolic disorders. In fermented foods such as cheeses, however, salt can impact the activity of desirable and undesirable microorganisms and thus affect their properties. This study aimed to investigate the effect of salt level on Swiss-type cheese ripening. Since proteolysis is a major event in cheese ripening, three strains of Lactobacillus helveticus were selected on the cell-envelope proteinase (CEP) they harbor. Their proteolytic activity on caseins was studied at six salt levels (0-4.5%) at pH 7.5 and 5.2. Swiss-type cheeses were manufactured at regular, increased, and decreased salt concentrations, and characterized for their composition and techno-functional properties. L. helveticus strains possessed and expressed the expected CEPs, as shown by PCR and shaving experiments. The two strains of L. helveticus that possessed at least the CEP PrtH3 showed the greatest proteolytic activity. Casein hydrolysis in vitro was similar or higher at pH 5.2, i.e., cheese pH, compared to pH 7.5, and slightly decreased at the highest salt concentrations (3.0 and 4.4%). Similarly, in ripened cheeses, these L. helveticus strains showed 1.5-2.4 more proteolysis, compared to the cheeses manufactured without L. helveticus . Regarding the salt effect, the 30% salt-reduced cheeses showed the same proteolysis as regular cheeses, while the upper-salted cheeses showed a slight decrease (-14%) of the non-protein fraction. The microbial and biochemical composition remained unchanged in the 30%-reduced cheeses. In contrast, Propionibacterium freudenreichii , used as ripening bacteria in Swiss cheese, grew more slowly in upper-salted (1.14%, w/w) cheeses, which induced concomitant changes in the metabolites they consumed (-40% lactic acid) or produced (fivefold decrease in propionic acid). Some cheese techno-functional properties were slightly decreased by salt reduction, as extrusion (-17%) and oiling off (-4%) compared to regular cheeses. Overall, this study showed that a 30% salt reduction has little impact in the properties of Swiss-type cheeses, and that starters and ripening cultures strains could be chosen to compensate changes induced by salt modifications in Swiss-type and other hard cheeses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gagnaire, Lecomte, Richoux, Genay, Jardin, Briard-Bion, Kerjean and Thierry.)

High Temperature-Short Time (HTST) pasteurization was proposed as an alternative to Holder pasteurization (HOP) to increase the retention of specific human milk (HM) bioactive proteins. The present study explored whether HTST and HOP differently affect peptide release during simulated preterm infant gastrointestinal digestion. Raw (RHM), HOP- and HTST- pasteurized HM were digested using an in vitro dynamic system, and the identified peptides were analyzed by mass spectrometry and multivariate statistics. Before digestion, 158 peptides were identified in either RHM, HTST- or HOP- HM, mostly (84.4%) originating from β-casein (CASB). During gastric digestion, HOP-HM presented a greater number and more abundant specific CASB peptides. A delayed release of peptides was observed in RHM during the intestinal phase, with respect to both pasteurized HM. Although limited to gastric digestion, the HM peptidomic profile differed according to the pasteurization type, and the pattern of the HTST peptides showed a greater similarity with RHM., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Lactic acid bacteria (LAB) are responsible for the sanitary, organoleptic, and health properties of most fermented products. Positive interactions between pairs of LAB strains, based on nitrogen dependencies, were previously demonstrated. In a chemically defined medium, using milk and lupin proteins as sole nitrogen source, two proteolytic strains were able to sustain the growth of non-proteolytic strains, but one did not. The objective of the present study was, thus, to determine which specific peptides were implicated in the positive interactions observed. Peptides produced and involved in the bacterial interactions were quantified using tandem mass spectrometry (LC-MS/MS). About 2,000 different oligopeptides ranging from 6 to more than 50 amino acids in length were identified during the time-course of the experiment. We performed a clustering approach to decipher the differences in peptide production during fermentation by the three proteolytic strains tested. We also performed sequence alignments on parental proteins and identified the cleavage site profiles of the three bacterial strains. Then, we characterized the peptides that were used by the non-proteolytic strains in monocultures. Hydrophobic and branched-chain amino acids within peptides were identified as essential in the interactions. Ultimately, better understanding how LAB can positively interact could be useful in multiple food-related fields, e.g ., production of fermented food products with enhanced functional properties, or fermentation of new food matrices., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Canon, Briard-Bion, Jardin, Thierry and Gagnaire.)

The specificity of pepsin, the major protease of gastric digestion, has been previously investigated, but only regarding the primary sequence of the protein substrates. The present study aimed to consider in addition physicochemical and structural characteristics, at the molecular and sub-molecular scales. For six different proteins submitted to in vitro gastric digestion, the peptide bonds cleaved were determined from the peptides released and identified by LC-MS/MS. An original statistical approach, based on propensity scores calculated for each amino acid residue on both sides of the peptide bonds, concluded that preferential cleavage occurred after Leu and Phe, and before Ile. Moreover, reliable statistical models developed for predicting peptide bond cleavage, highlighted the predominant role of the amino acid residues at the N-terminal side of the peptide bonds, up to the seventh position (P7 and P7'). The significant influence of hydrophobicity, charge and structural constraints around the peptide bonds was also evidenced., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Propionibacterium freudenreichii is a probiotic Gram-positive bacterium with promising immunomodulatory properties. It modulates regulatory cytokines, mitigates the inflammatory response in vitro and in vivo These properties were initially attributed to specific bacterial surface proteins. Recently, we showed that extracellular vesicles (EVs) produced by P. freudenreichii CIRM-BIA129 mimic the immunomodulatory features of parent cells in vitro (i.e. modulating NF-κB transcription factor activity and IL-8 release) which underlies the role of EVs as mediators of the probiotic effects of the bacterium. The modulation of EV properties, and particularly of those with potential therapeutic applications such as the EVs produced by the probiotic P. freudenreichii , is one of the challenges in the field to achieve efficient yields with the desired optimal functionality. Here we evaluated whether the culture medium in which the bacteria are grown could be used as a lever to modulate the protein content and hence the properties of P. freudenreichii CIRM-BIA129 EVs. The physical, biochemical and functional properties of EVs produced from cells cultivated on laboratory Yeast Extract Lactate (YEL) medium and cow milk ultrafiltrate (UF) medium were compared. UF-derived EVs were more abundant, smaller in diameter and displayed more intense anti-inflammatory activity than YEL-derived EVs. Furthermore, the growth media modulated EV content in terms of both the identities and abundances of their protein cargos, suggesting different patterns of interaction with the host. Proteins involved in amino acid metabolism and central carbon metabolism were modulated, as were the key surface proteins mediating host-propionibacteria interactions. Importance Extracellular vesicles (EVs) are cellular membrane-derived nanosized particles that are produced by most cells in all three kingdoms of life. They play a pivotal role in cell-cell communication through their ability to transport bioactive molecules from donor to recipient cells. Bacterial EVs are important factors in host-microbe interactions. Recently we have shown that EVs produced by the probiotic P. freudenreichii exhibited immunomodulatory properties. We evaluate here the impact of environmental conditions, notably culture media, on P. freudenreichii EV production and function. We show that EVs display considerable differences in protein cargo and immunomodulation depending on the culture medium used. This work offers new perspectives for the development of probiotic EV-based molecular delivery systems, and reinforces the optimization of growth conditions as a tool to modulate the potential therapeutic applications of EVs., (Copyright © 2020 de Rezende Rodovalho et al.)

A recent work revealed that egg white (EW) at 45 °C exhibits powerful bactericidal activity against S. enterica serovar Enteritidis, which is surprisingly little affected by removal of the >10 kDa EW proteins. Here, we sought to identify the major EW factors responsible for this bactericidal activity by fractionating EW using ultrafiltration and nanofiltration and by characterizing the physicochemical and antimicrobial properties of the resulting fractions. In particular, 22 peptides were identified by nano-LC/MS-MS and the bactericidal activities of representative peptides (with predicted antimicrobial activity) were further assessed. Two peptides (FVPPVQR and GDPSAWSWGAEAHS) were found to be bactericidal against S. enterica serovar Enteritidis at 45 °C when provided in an EW environment. Nevertheless, these peptides contribute only part of this bactericidal activity, suggesting other, yet to be determined, antimicrobial factors.

Breast milk is the gold standard in neonatal nutrition, but most infants are fed infant formulas in which lipids are usually of plant origin. The addition of dairy lipids and/or milk fat globule membrane extracts in formulas improves their composition with beneficial consequences on protein and lipid digestion. The probiotic Lactobacillus fermentum (Lf) was reported to reduce transit time in rat pups, which may also improve digestion. This study aimed to investigate the effects of the addition of dairy lipids in formulas, with or without Lf, on protein and lipid digestion and on gut physiology and metabolism. Piglets were suckled from postnatal days 2 to 28, with formulas containing either plant lipids (PL), a half-half mixture of plant and dairy lipids (DL), or this mixture supplemented with Lf (DL+Lf). At day 28, piglets were euthanized 90 min after their last feeding. Microstructure of digesta did not differ among formulas. Gastric proteolysis was increased ( P < 0.01) in DL and DL+Lf (21.9 ± 2.1 and 22.6 ± 1.3%, respectively) compared with PL (17.3 ± 0.6%) and the residual proportion of gastric intact caseins decreased ( p < 0.01) in DL+Lf (5.4 ± 2.5%) compared with PL and DL (10.6 ± 3.1% and 21.8 ± 6.8%, respectively). Peptide diversity in ileum and colon digesta was lower in PL compared to DL and DL+Lf. DL and DL+Lf displayed an increased ( p < 0.01) proportion of diacylglycerol/cholesterol in jejunum and ileum digesta compared to PL and tended ( p = 0.07) to have lower triglyceride/total lipid ratio in ileum DL+Lf (0.019 ± 0.003) as compared to PL (0.045 ± 0.011). The percentage of endocrine tissue and the number of islets in the pancreas were decreased ( p < 0.05) in DL+Lf compared with DL. DL+Lf displayed a beneficial effect on host defenses [increased goblet cell density in jejunum ( p < 0.05)] and a trophic effect [increased duodenal ( p = 0.09) and jejunal ( p < 0.05) weights]. Altogether, our results demonstrate that the addition of dairy lipids and probiotic Lf in infant formula modulated protein and lipid digestion, with consequences on lipid profile and with beneficial, although moderate, physiological effects., Competing Interests: IC, PL, and CB are employees of Lactalis. ML received a grant from Lactalis Recherche et Développement (Retiers, France) and from the Association Nationale de la Recherche et de la Technologie (ANRT) (Grant CIFRE No. 2014/0580). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Lemaire, Ménard, Cahu, Nogret, Briard-Bion, Cudennec, Cuinet, Le Ruyet, Baudry, Dupont, Blat, Deglaire and Le Huërou-Luron.)

This study investigated the effect of pH on the denaturation extent, the surface chemical composition, the water sorption isotherm and the glass transition temperature of camel and bovine whey protein's powders. The LC-MS analysis indicated that the β-Lactoglobulin was the most denatured protein in bovine whey powders regardless the pH value, while this protein was totally absent in camel whey. The α-Lactalbumin was relatively heat stable after drying and predominated the powder surface (X-ray photoelectron spectroscopy results) in both camel and bovine whey powders regardless the pH (neutral (6.7) or acidic (4.3 and 4.6)). Analysis of the water sorption isotherms indicated that decreasing the pH induced the increase of the water activity of lactose crystallization for camel and bovine whey powders. Finally, decreasing the pH led to the decrease of the glass transition temperature of camel and bovine whey powder (at 0.13, 0.23, and 0.33 of water activity)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Propionibacterium freudenreichii is a beneficial bacterium that modulates the gut microbiota, motility and inflammation. It is traditionally consumed within various fermented dairy products. Changes to consumer habits in the context of food transition are, however, driving the demand for non-dairy fermented foods, resulting in a considerable development of plant-based fermented products that require greater scientific knowledge. Fermented soymilks, in particular, offer an alternative source of live probiotics. While the adaptation of lactic acid bacteria (LAB) to such vegetable substrates is well documented, little is known about that of propionibacteria. We therefore investigated the adaptation of Propionibacterium freudenreichii to soymilk by comparison to cow's milk. P. freudenreichii grew in cow's milk but not in soymilk, but it did grow in soymilk when co-cultured with the lactic acid bacterium Lactobacillus plantarum . When grown in soymilk ultrafiltrate (SUF, the aqueous phase of soymilk), P. freudenreichii cells appeared thinner and rectangular-shaped, while they were thicker and more rounded in cow's milk utltrafiltrate (MUF, the aqueous phase of cow milk). The amount of extractable surface proteins (SlpA, SlpB, SlpD, SlpE) was furthermore reduced in SUF, when compared to MUF. This included the SlpB protein, previously shown to modulate adhesion and immunomodulation in P. freudenreichii . Tolerance toward an acid and toward a bile salts challenge were enhanced in SUF. By contrast, tolerance toward an oxidative and a thermal challenge were enhanced in MUF. A whole-cell proteomic approach further identified differential expression of 35 proteins involved in amino acid transport and metabolism (including amino acid dehydrogenase, amino acid transporter), 32 proteins involved in carbohydrate transport and metabolism (including glycosyltransferase, PTS), indicating metabolic adaptation to the substrate. The culture medium also modulated the amount of stress proteins involved in stress remediation: GroEL, OpuCA, CysK, DnaJ, GrpE, in line with the modulation of stress tolerance. Changing the fermented substrate may thus significantly affect the fermentative and probiotic properties of dairy propionibacteria. This needs to be considered when developing new fermented functional foods., Competing Interests: FGa was employed by the French company Bioprox. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Tarnaud, Gaucher, do Carmo, Illikoud, Jardin, Briard-Bion, Guyomarc’h, Gagnaire and Jan.)

The high-temperature short-time (HTST, 72 °C, 15 s) pasteurization of human milk (HM) has been proposed as an alternative to the Holder method (HoP, 62.5 °C, 30 min), to increase the preservation of bioactive compounds. We have investigated the impact of HTST and HoP pasteurization on the gastrointestinal kinetics of human milk, using a dynamic in vitro system in a preterm newborn model. An increased protein aggregation on the surface of fat globules following pasteurization, albeit to a lesser extent in HTST than in HoP, was observed. Despite relevant differences in the undigested milk samples, both pasteurization methods led to similar proteolytic patterns, while raw HM presented a higher native lactoferrin content throughout digestion. The slightly decreased amino acid release following HoP, with respect to HTST and raw HM, indicated that peptidomic analysis, which is currently underway, might provide interesting insights on the differential digestive kinetics of differently pasteurized HM., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: MG, LC, EB and AC have competing interests, since they are the inventors of a patent pertaining to the HTST human milk pasteurizer used in the study (Patent no. EP2974603 A1). No conflict of interest exists for the remaining authors., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

As plant proteins are increasingly used as a source of amino acids in the diet, studies on in vitro digestion of plant proteins are key to understand the different factors affecting proteolysis, with the ultimate goal of optimising the nutritional composition/intake of plant protein-rich products. More realistic scenarios including the most likely food matrix and physiologically relevant gastrointestinal (GI) conditions should be considered when assessing the in vitro digestion of proteins. The research described here compares the extent of hydrolysis of proteins from peanuts and wheat bread, in particular the vicilin-like 7S globulin (Ara h 1) and gliadin, respectively, with three GI scenarios simulating either infant, early phase adult (fed state) or late phase adult (fasted state) conditions. The digestibility of these proteins, in isolation or when naturally present in the respective food matrix, has been evaluated with SDS-PAGE, LC-MS/MS and a spectrophotometric assay. Results from the food matrices showed lower extent of total protein GI digestion under simulated infant conditions, intermediate behaviour under fed state adult conditions and larger extent under fasted state adult conditions. This was also the case for isolated gliadin. However, isolated Ara h 1 only showed lower extent of proteolysis in the gastric phase under infant conditions, reaching a similar extent to both adult conditions over the course of the intestinal phase. The food matrix seems to have delayed the proteolysis. Choosing an appropriate GI scenario as well as the matrix of the end food product is paramount when assessing in vitro protein digestion.

Extracellular vesicles (EVs) are nanometric spherical structures involved in intercellular communication, whose production is considered to be a widespread phenomenon in living organisms. Bacterial EVs are associated with several processes that include survival, competition, pathogenesis, and immunomodulation. Among probiotic Gram-positive bacteria, some Propionibacterium freudenreichii strains exhibit anti-inflammatory activity, notably via surface proteins such as the surface-layer protein B (SlpB). We have hypothesized that, in addition to surface exposure and secretion of proteins, P. freudenreichii may produce EVs and thus export immunomodulatory proteins to interact with the host. In order to demonstrate their production in this species, EVs were purified from cell-free culture supernatants of the probiotic strain P. freudenreichii CIRM-BIA 129, and their physicochemical characterization, using transmission electron microscopy and nanoparticle tracking analysis (NTA), revealed shapes and sizes typical of EVs. Proteomic characterization showed that EVs contain a broad range of proteins, including immunomodulatory proteins such as SlpB. In silico protein-protein interaction predictions indicated that EV proteins could interact with host proteins, including the immunomodulatory transcription factor NF-κB. This potential interaction has a functional significance because EVs modulate inflammatory responses, as shown by IL-8 release and NF-κB activity, in HT-29 human intestinal epithelial cells. Indeed, EVs displayed an anti-inflammatory effect by modulating the NF-κB pathway; this was dependent on their concentration and on the proinflammatory inducer (LPS-specific). Moreover, while this anti-inflammatory effect partly depended on SlpB, it was not abolished by EV surface proteolysis, suggesting possible intracellular sites of action for EVs. This is the first report on identification of P. freudenreichii- derived EVs, alongside their physicochemical, biochemical and functional characterization. This study has enhanced our understanding of the mechanisms associated with the probiotic activity of P. freudenreichii and identified opportunities to employ bacterial-derived EVs for the development of bioactive products with therapeutic effects., (Copyright © 2020 Rodovalho, Luz, Rabah, do Carmo, Folador, Nicolas, Jardin, Briard-Bion, Blottière, Lapaque, Jan, Le Loir, de Carvalho Azevedo and Guédon.)

Evaluating the gastrointestinal (GI) fate of proteins is part of the assessment to determine whether proteins are safe to consume. In vitro digestion tests are often used for screening purposes in the evaluation of potential allergenicity. However, the current pepsin resistant test used by the European Food Safety Authority, only corresponds to fasted gastric conditions representative of a late phase adult stomach. In addition, these tests are performed on isolated proteins and the effect of the food matrix and processing are not systematically considered. The aim of this research is to compare three different static in vitro GI scenarios that are physiologically relevant. Namely, an infant, early phase (fed state) adult and late phase (fasted state) adult model. These protocols are applied to well-characterised isolated dairy (β-lactoglobulin and β-casein) and egg (lysozyme and ovalbumin) proteins and the impact of food matrix/processing on their proteolysis is also investigated. A combination of SDS-PAGE, LC-MS/MS and spectrophotometric assay was used for the evaluation of the proteolysis. Results highlight differences across the three GI scenarios whether on isolated proteins or within food matrices. The infant model led to incomplete digestion, leaving intact egg proteins, either isolated or in the food matrix, and intact β-lactoglobulin in the milk. In addition, peptides greater than 9 amino acids were found throughout the intestinal phase for all proteins studied, regardless of the scenario. This reinforces the difficulty of linking protein digestibility to potential allergenicity because many other factors are involved that need further investigation.

Staphylococcus aureus is an important opportunistic pathogen of humans and animals. It produces extracellular vesicles (EVs) that are involved in cellular communication and enable inter-kingdom crosstalk, the delivery of virulence factors and modulation of the host immune response. The protein content of EVs determines their biological functions. Clarifying which proteins are selected, and how, is of crucial value to understanding the role of EVs in pathogenesis and the development of molecular delivery systems. Here, we postulated that S. aureus EVs share a common proteome containing components involved in cargo sorting. The EV proteomes of five S. aureus strains originating from human, bovine, and ovine hosts were characterised. The clustering of EV proteomes reflected the diversity of the producing strains. A total of 253 proteins were identified, 119 of which composed a core EV proteome with functions in bacterial survival, pathogenesis, and putatively in EV biology. We also identified features in the sequences of EV proteins and the corresponding genes that could account for their packaging into EVs. Our findings corroborate the hypothesis of a selective sorting of proteins into EVs and offer new perspectives concerning the roles of EVs in S. aureus pathogenesis in specific host niches.

The aim of this work was to evaluate the impact of incorporating different legume flours (faba bean, lentil or split pea flours) on the pasta protein network and its repercussion on in vitro protein digestibility, in comparison with reference dairy proteins. Kinetics and yields of protein hydrolysis in legume enriched pasta and, for the first time, the peptidomes generated by the pasta at the end of the in vitro gastric and intestinal phases of digestion are presented. Three isoproteic (21%) legume enriched pasta with balanced essential amino acids, were made from wheat semolina and 62% to 79% of legume flours (faba bean or F-pasta; lentil or L-pasta and split pea or P-pasta). Pasta were prepared following the conventional pastification steps (hydration, mixing, extrusion, drying, cooking). Amino acid composition and protein network structure of the pasta were determined along with their culinary and rheological properties and residual trypsin inhibitor activity (3-5% of the activity initially present in raw legume flour). F- and L-pasta had contrasted firmness and proportion of covalently linked proteins. F-pasta had a generally weaker protein network and matrix structure, however far from the weakly linked soluble milk proteins (SMP) and casein proteins, which in addition contained no antitrypsin inhibitors and more theoretical cleavage sites for digestive enzymes. The differences in protein network reticulation between the different pasta and between pasta and dairy proteins were in agreement in each kinetic phase with the yield of the in vitro protein hydrolysis, which reached 84% for SMP, and 66% for casein at the end of intestinal phase, versus 50% for L- and P-pasta and 58% for F-pasta. The peptidome of legume enriched pasta is described for the first time and compared with the peptidome of dairy proteins for each phase of digestion. The gastric and intestinal phases were important stages of peptide differentiation between legumes and wheat. However, peptidome analysis revealed no difference in wheat-derived peptides in the three pasta diets regardless of the digestion phase, indicating that there was a low covalent interaction between wheat gluten and legume proteins., Competing Interests: The authors have declared that no competing interests exist.

The article presents a proteomic data set generated by a comparative analysis of the proteomes of Propionibacterium freudenreichii, comparing the CIRM-BIA 129 and CIRM-BIA 1025 strains. The two strains were cultivated until the beginning of the stationary phase in a chemical defined medium (MMO), and in this medium in the presence of NaCl, with or without glycine betaine. Whole-cell proteins were extracted, trypsinolyzed and analyzed by nano LC-MS/MS, prior to identification and classification by function using the X!Tandem pipeline software and the proteomic data from NCBI.nlm.nigh.gov. Quantification of proteins was then carried out in order to detect change in their expression depending on the culture medium. This article is related to the research article entitled "Benefits and drawbacks of osmotic adjustment in Propionibacterium freudenreichii ". The comparative proteomic analysis of the two strains reveal strain-dependent and medium-dependent stress proteomes in the probiotic P. freudenreichii ., (© 2019 The Authors.)

Propionibacterium freudenreichii is a beneficial bacterium with documented effects on the gut microbiota and on inflammation. Its presence within the animal and human intestinal microbiota was correlated with immunomodulatory effects, mediated by both propionibacterial surface components and by secreted metabolites. It is widely implemented, both in the manufacture of fermented dairy products such as Swiss-type cheeses, and in the production of probiotic food complements, under the form of freeze-dried powders. The bottleneck of this drying process consists in the limited survival of bacteria during drying and storage. Protective pre-treatments have been applied to other bacteria and may, in a strain-dependent manner, confer enhanced resistance. However, very little information was yet published on P. freudenreichii adaptation to freeze-drying. In this report, an immunomodulatory strain of this probiotic bacterium was cultured under hyperosmotic constraint in order to trigger osmoadaptation. This adaptation was then combined with acid or thermal pre-treatment. Such combination led to accumulation of key stress proteins, of intracellular compatible solute glycine betaine, to modulation of the propionibacterial membrane composition, and to enhanced survival upon freeze-drying. This work opens new perspectives for efficient production of live and active probiotic propionibacteria., (Copyright © 2019 Gaucher, Kponouglo, Rabah, Bonnassie, Ossemond, Pottier, Jardin, Briard-Bion, Marchand, Blanc, Jeantet and Jan.)

Background: Breastfeeding is protective against many long-term diseases, yet the mechanisms involved are unknown. Leptin gene (LEP) is reported to be associated with body mass index (BMI). On the other hand, breastfeeding duration has been found to be associated with DNA methylation (DNAm) of the LEP gene. Therefore, epigenetic regulation of LEP may represent the mechanism underlying the protective effect of breastfeeding duration against obesity., Methods: In the Isle of Wight Birth Cohort, peripheral blood DNAm at 23 cytosine-phosphate-guanine sites (CpGs) in the LEP locus in 10-year-old (n = 297) samples and 16 CpGs in 18-year-old (n = 305) samples, were generated using the Illumina Infinium MethylationEPIC and HumanMethylation450 Beadchips respectively and tested for association with breastfeeding duration (total and exclusive) using linear regression. To explore the association between breastfeeding durations and genome-wide DNAm, epigenome-wide association studies (EWASs) and differential methylation region (DMR) analyses were performed. BMI trajectories spanning the first 18 years of life were used as the outcome to test the association with breastfeeding duration (exposure) using multi-nominal logistic regression. Mediation analysis was performed for significant CpG sites., Results: Both total and exclusive breastfeeding duration were associated with DNAm at four LEP CpG sites at 10 years (P value < 0.05), and not at 18 years. Though no association was observed between breastfeeding duration and genome-wide DNAm, DMR analyses identified five significant differentially methylated regions (Sidak adjusted P value < 0.05). Breastfeeding duration was also associated with the early transient overweight trajectory. Furthermore, DNAm of LEP was associated with this trajectory at one CpG site and early persistent obesity at another, though mediation analysis was not significant., Conclusions: Breastfeeding duration is associated with LEP methylation at age 10 years and BMI trajectory. LEP DNAm is also significantly associated with BMI trajectories throughout childhood, though sample sizes were small. However, mediation analysis did not demonstrate that DNAm of LEP explained the protective effect of breastfeeding against childhood obesity.

Propionibacterium freudenreichii is a beneficial bacterium used as a cheese starter and as a probiotic. Indeed, selected strains of P. freudenreichii combine both technological and health-promoting abilities. Moreover, during large-scale industrial production of dried bacteria and during consumption, P. freudenreichii may undergo different stressful processes. Osmotic adaptation was shown to enhance P. freudenreichii tolerance towards stresses, which are encountered during freeze-drying and during digestion. In this report, we compared the osmoadaptation molecular mechanisms of two P. freudenreichii strains. Both osmotolerance and osmoadaptation were strain-dependent and had different effects on multiple stress tolerance, depending on the presence of osmoprotectants. Availability of glycine betaine (GB) restored the growth of one of the two strains. In this strain, osmotic preadaptation enhanced heat, oxidative and acid stresses tolerance, as well as survival upon freeze-drying. However, addition of GB in the medium had deleterious effects on stress tolerance, while restoring optimal growth under hyperosmotic constraint. In the other strain, neither salt nor GB enhanced stress tolerance, which was constitutively low. Accordingly, whole cell proteomics revealed that mechanisms triggered by salt in the presence and in the absence of GB are different between strains. Osmotic adjustment may thus have deleterious effects on industrial abilities of P. freudenreichii. BIOLOGICAL SIGNIFICANCE: Propionibacteria are found in various niches including fodder, silage, rumen, milk and cheeses. This means adaptation towards different ecological environments with different physicochemical parameters. Propionibacterium freudenreichii, in particular, is furthermore used both as dairy starter and as probiotic and is thus submitted to high scale industrial production. Production and subsequent stabilization still need optimization. Drying processes like freeze-drying are stressful. Osmotic adjustments may modulated tolerance towards drying. However, they are strain-dependent, medium-dependent and may either reduce or increase stress tolerance. A case-by-case study, for each strain-medium thus seems necessary. In this work, we identify key proteins involved in osmoadaptation and give new insights into adaptation mechanisms in P. freudenreichii. This opens new perspectives for the selections of strains and for the choice of the growth medium composition., (Copyright © 2019. Published by Elsevier B.V.)

Holder pasteurization (62.5 °C, 30 min) of human milk denatures beneficial proteins. The present paper aimed to assess whether this can affect the kinetics of peptide release during digestion at the preterm stage. Raw (RHM) or pasteurized (PHM) human milk were digested in triplicates using an in vitro dynamic system. Mass spectrometry and multivariate statistics were conducted. Pre-proteolysis occurred mostly on β-casein, for which cumulative peptide abundance was significantly greater in PHM over 28% of the hydrolysed sequence. Eight clusters resumed the kinetics of peptide release during digestion, which differed on seven clusters (69% of the 1134 peptides). Clusters associated to the heat-denaturated proteins, lactoferrin and bile salt-stimulated lipase, presented different kinetics of release during digestion, unlike that for β-casein. Some bioactive peptides from β-casein presented significant different abundances between PHM and RHM before digestion (1-18, 185-211) or in during intestinal digestion (154-160, 161-166). Further physiological consequences should be investigated., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Purpose: Sleep disturbance is common in intensive care units. It is associated with detrimental psychological impacts and has potential to worsen outcome. Irregular exposure to sound and light may disrupt circadian rhythm and cause frequent arousals from sleep. We sought to review the efficacy of environmental interventions to reduce sound and light exposure with the aim of improving patient sleep on adult intensive care units., Methods: We searched both PubMed (1966-30 May 2017) and Embase (1974-30 May 2017) for all relevant human (adult) studies and meta-analyses published in English using search terms ((intensive care OR critical care), AND (sleep OR sleep disorders), AND (light OR noise OR sound)). Bibliographies were explored. Articles were included if reporting change in patient sleep in response to an intervention to reduce disruptive intensive care unit sound /light exposure., Results: Fifteen studies were identified. Nine assessed mechanical interventions, four of which used polysomnography to assess sleep. Five studies looked at environmental measures to facilitate sleep and a further two (one already included as assessing a mechanical intervention) studied the use of sound to promote sleep. Most studies found a positive impact of the intervention on sleep. However, few studies used objective sleep assessments, sample sizes were small, methodologies sometimes imperfect and analysis limited. Data are substantially derived from specialist (neurosurgical, post-operative, cardiothoracic and cardiological) centres. Patients were often at the 'less sick' end of the spectrum in a variety of settings (open ward beds or side rooms)., Conclusions: Simple measures to reduce intensive care unit patient sound/light exposure appear effective. However, larger and more inclusive high-quality studies are required in order to identify the measures most effective in different patient groups and any impacts on outcome.

Improving the nutritional and health properties of food products, e.g. infant milk formula, by the addition of functional ingredients is of primary importance. This study focused on bioactive milk polar lipids (PLs) recovered from dietary sources that are of increasing interest. The chemical compositions of buttermilks and butter serums were determined and the modulation of the fatty acid composition of milk PLs was investigated. Butter serums contain a higher amount of milk PLs than buttermilks (88 vs. 13-18g/kg dry matter), with a higher proportion of sphingomyelin (34 vs. 19% of PLs, respectively) interestingly close to human milk PL profile. Butter serums are also interesting sources of choline, an important nutrient for infant brain development. We demonstrated that the unsaturated fatty acid content of milk PLs recovered in the buttermilks and the butter serums, mainly the amount of C18:3n-3 and C22:6n-3 (DHA) that are of nutritional interest, can be increased by dietary strategies. This work opens perspectives for a better valorization of milk PLs in human nutrition (both infants and adults) to benefit their functional, nutritional and health properties., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Chymosin is the major enzyme used in cheesemaking but latex enzymes are also used. The aim of this work was to characterize the composition and the structure of dairy gel obtained by an extract of Calotropis procera leaves in comparison with those obtained by chymosin. The biochemical and mineral compositions of the curds and the cheese yields obtained by using Calotropis procera extract or chymosin were relatively similar. Quantitative and qualitative evaluations of proteolysis after milk coagulation, determined by the non-protein nitrogen content and chromatography coupled to mass spectrometry, indicated that Calotropis procera extract was more proteolytic than chymosin and that κ-casein was proteolyzed. The main consequence of proteolysis by Calotropis procera extract or chymosin was the formation of a similar and regular network with the presence of aggregates of casein micelles. These results support that Calotropis procera extract can be used as effective coagulant in cheesemaking., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Propionibacterium freudenreichii, a dairy starter, can reach a population of almost 10 9 propionibacteria per gram in Swiss-type cheese at the time of consumption. Also consumed as a probiotic, it displays strain-dependent anti-inflammatory properties mediated by surface proteins that induce IL-10 in leukocytes. We selected 23 strains with varied anti-inflammatory potentials in order to identify the protein(s) involved. After comparative genomic analysis, 12 of these strains were further analysed by surface proteomics, eight of them being further submitted to transcriptomics. The omics data were then correlated to the anti-inflammatory potential evaluated by IL-10 induction. This comparative omics strategy highlighted candidate genes that were further subjected to gene-inactivation validation. This validation confirmed the contribution of surface proteins, including SlpB and SlpE, two proteins with SLH domains known to mediate non-covalent anchorage to the cell-wall. Interestingly, HsdM3, predicted as cytoplasmic and involved in DNA modification, was shown to contribute to anti-inflammatory activity. Finally, we demonstrated that a single protein cannot explain the anti-inflammatory properties of a strain. These properties therefore result from different combinations of surface and cytoplasmic proteins, depending on the strain. Our enhanced understanding of the molecular bases for immunomodulation will enable the relevant screening for bacterial resources with anti-inflammatory properties.

Unlabelled: Propionibacterium freudenreichii is used as a cheese-ripening starter and as a probiotic. Its reported physiological effects at the gut level, including modulation of bifidobacteria, colon epithelial cell proliferation and apoptosis, and intestinal inflammation, rely on active metabolism in situ Survival and activity are thus key factors determining its efficacy, creating stress adaptation and tolerance bottlenecks for probiotic applications. Growth media and growth conditions determine tolerance acquisition. We investigated the possibility of using sweet whey, a dairy by-product, to sustain P. freudenreichii growth. It was used at different concentrations (dry matter) as a culture medium. Using hyperconcentrated sweet whey led to enhanced multistress tolerance acquisition, overexpression of key stress proteins, and accumulation of intracellular storage molecules and compatible solutes, as well as enhanced survival upon spray drying. A simplified process from growth to spray drying of propionibacteria was developed using sweet whey as a 2-in-1 medium to both culture P. freudenreichii and protect it from heat and osmotic injury without harvesting and washing steps. As spray drying is far cheaper and more energy efficient than freeze-drying, this work opens new perspectives for the sustainable development of new starter and probiotic preparations with enhanced robustness., Importance: In this study, we demonstrate that sweet whey, a dairy industry by-product, not only allows the growth of probiotic dairy propionibacteria, but also triggers a multitolerance response through osmoadaptation and general stress response. We also show that propionibacteria accumulate compatible solutes under these culture conditions, which might account for the limited loss of viability after spray drying. This work opens new perspectives for more energy-efficient production of dairy starters and probiotics., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)