Coffee silverskin (CSS), the major by-product of coffee roasting, is reported to contain bioactive compounds, including xanthines and polyphenols, showing promising potential for food and nutraceutical applications. This study investigated the beneficial effects of CSS hydroalcoholic extracts, which were chemically characterized by Attenuated Total Reflectance-Fourier-Transform Infrared Spectroscopy and ElectroSpray Ionization tandem Mass Spectrometry, on Caenorhabditis elegans physiology. CSS supplementation improved healthspan-related parameters and delayed aging-associated functional decline, without significantly extending lifespan in wild-type nematodes. Treated worms exhibited a 57% reduction in reactive oxygen species (ROS) levels and upregulation of antioxidant genes (gst-4 and sod-3), suggesting that CSS mitigates oxidative stress through the DAF-2/DAF-16 pathway. Under high-glucose diet conditions, CSS reduced lipid droplet accumulation and modulated the expression of metabolic genes, including upregulation of nhr-49 which is a key regulator of fatty acid oxidation. CSS restored lipid homeostasis and rescued the shortened lifespan of obese nhr-49 mutant worms, suggesting enhanced β-oxidation. Moreover, CSS modulated serotonergic signaling by increasing tph-1 and ser-6 expression, linking its effects to serotonin-mediated regulation of fat metabolism. Finally, CSS promoted the growth of probiotic strains, suggesting potential prebiotic properties. Overall, these findings identify CSS as a metabolic modulator capable of alleviating oxidative and metabolic stress, supporting its sustainable application in the development of functional foods and nutraceuticals.

Dietary fiber is considered an important health-promoting food component; however, to better characterize associations between fiber consumption and health outcomes, it is important to identify reliable biomarkers of intake. Dietary fiber includes all nondigestible carbohydrates that are characterized by different chemical structures, yet have a common resistance to digestion and absorption in the intestine, where they act as substrates for the resident microbiota. Considering the structural complexity and diversity of fiber, its physico-chemical properties, the abundance of fiber-rich foods, and the complexity of the gut microbiota, the identification of biomarkers of fiber intake is quite challenging. To this aim, a narrative review was performed to define the critical issues for fiber biomarker identification and then to analyze and validate putative biomarkers of total fiber intake. On the basis of the common properties of the different types of fiber, we have identified the following as possible candidate biomarkers: fecal fiber components; stool weight; fecal microbiota composition; microbiota metabolites, such as fecal and plasma short-chain fatty acids and plasma odd-chain fatty acids; and breath hydrogen and methane. The scientific evidence to support their role as biomarkers of intake was evaluated by applying the validation criteria developed by the FoodBAll Consortium. We also explored whether a combination of validated biomarkers of food intake relative to the main dietary fiber sources could be considered to develop a score-like evaluation of fiber consumption in dietary patterns. What emerged from our analysis was that the complexity of the relationship between diet, fiber composition, and microbiota, as well as the limited and fragmented scientific evidence currently hamper the identification of robust biomarkers of fiber intake. Indeed, none of the potential biomarkers considered in our analysis completely fulfilled all of the validation criteria; however, microbiota composition and breath hydrogen appeared to be the most promising candidates.

The increasing interest in fermented foods stems from their health benefits, mediated by foodborne microorganisms. This study aimed to characterize the fermentative microbiota of Pecorino di Picinisco, a traditional Italian cheese made from ovine raw milk, and to evaluate the probiotic and technological potential of selected lactic acid bacteria strains. Three strains representative of the different species found (Lactococcus lactis, Lactiplantibacillus plantarum and Latilactobacillus curvatus) were chosen and analyzed. All three strains were able to adhere to human intestinal Caco-2 cells, were resistant to simulated in vitro digestion and significantly prolonged the lifespan of Caenorhabditis elegans, used as a simplified in vivo model, with respect to the commercial probiotic strain Lacticaseibacillus rhamnosus GG. The L. plantarum Pic37.4 strain was particularly promising; therefore, its cell-free supernatant was employed to evaluate the antimicrobial activity against indicator strains of foodborne and intestinal pathogens or spoilage bacteria. The results demonstrated the effectiveness of the supernatant against all strains tested, with the strongest effect on the intestinal pathogen enterotoxigenic Escherichia coli K88. In addition, the inhibitory effect on pathogen adhesion to intestinal mucosa was investigated on Caco-2 cells, resulting in a significant reduction in adhesion mediated by the L. plantarum Pic37.4 supernatant. The antimicrobial properties of the L. plantarum strain were confirmed in vivo in C. elegans. These promising results lay the ground for further investigations aimed at substantiating the probiotic and technological potential of the L. plantarum Pic37.4 investigated in this work.

Several meta-analyses have consistently demonstrated that the consumption of an adequate level of fruit and vegetables (F&V), along with other food groups, is associated with a low risk of all-cause mortality, and, as such, represents one of the major modifiable risk factors related to the growing burden of Non-Communicable Diseases (NCDs). The aim of the present narrative review was to provide an up-to-date analysis of systematic reviews and meta-analyses published in the past five years, dealing with the effects of F&V consumption on human health, focusing on specific pathologies, such as total mortality, cancer, cardiovascular diseases (CVDs), type 2 diabetes, intestinal inflammation, and bone and respiratory illnesses. The results of our evaluation confirmed and consolidated the protective role of F&V consumption against the development of NCDs, especially CVDs. However, the need to corroborate existing evidence and clarify the role of confounding factors by performing additional randomized control trials and adopting more standardized approaches and study designs also emerged. Moreover, evaluating the protective role of fruit and vegetables as separate food categories appeared to be one of the most interesting areas to investigate in the near future. Overall, these outcomes could help in addressing future research to better establish a causal relationship between F&V consumption and human health.

Antimicrobial resistance (AMR) is a global and increasing threat to human health. Several genetic determinants of AMR are found in environmental reservoirs, including bacteria naturally associated with widely consumed fermented foods. Through the food chain, these bacteria can reach the gut, where horizontal gene transfer (HGT) can occur within the complex and populated microbial environment. Numerous studies on this topic have been published over the past decades, but a conclusive picture of the potential impact of the non-pathogenic foodborne microbial reservoir on the spread of AMR to human pathogens has not yet emerged. This review critically evaluates a comprehensive list of recent experimental studies reporting the isolation of AMR bacteria associated with fermented foods, focusing on those reporting HGT events, which represent the main driver of AMR spread within and between different bacterial communities. Overall, our analysis points to the methodological heterogeneity as a major weakness impairing determination or a causal relation between the presence of AMR determinants within the foodborne microbial reservoir and their transmission to human pathogens. The aim is therefore to highlight the main gaps and needs to better standardize future studies addressing the potential role of non-pathogenic bacteria in the spread of AMR.

BACKGROUND:Fermented foods are attracting increasing interest due to their nutritional and health benefits, including a positive impact on gut microbiota exerted by their associated microbes. However, information relative to traditional fermented dairy products, along with their autochthonous microbiota, is still fragmented and poorly standardized. Therefore, our aim was to collect and aggregate data useful for obtaining a comprehensive overview translated in a classical database interface that can be easily handled by users.METHODS:a preliminary inventory was built up by systematically collecting data from publicly available resources for the creation of a list of traditional dairy foods produced worldwide, including additional metadata useful for stratifying, and collapsing subgroups.RESULTS:we developed the Fermented Dairy Food Database (FDF-DB), a feasible resource comprising 1852 traditional dairy foods (cheeses, fermented milks, and yogurt) for which microbial content and other associated metadata such as geographical indication label, country/region of origin, technological aspects were gathered.CONCLUSIONS:FDF-DB is a useful and user-friendly resource where taxonomic information and processing production details converge. This resource will be of great aid for researchers, food industries, stakeholders and any user interested in the identification of technological and microbiological features characterizing traditional fermented dairy products.

Food ontologies are acquiring a central role in human nutrition, providing a standardized terminology for a proper description of intervention and observational trials. In addition to bioactive molecules, several fermented foods, particularly dairy products, provide the host with live microorganisms, thus carrying potential "genetic/functional" nutrients. To date, a proper ontology to structure and formalize the concepts used to describe fermented foods is lacking. Here we describe a semantic representation of concepts revolving around what consuming fermented foods entails, both from a technological and health point of view, focusing actions on kefir and Parmigiano Reggiano, as representatives of fresh and ripened dairy products. We included concepts related to the connection of specific microbial taxa to the dairy fermentation process, demonstrating the potential of ontologies to formalize the various gene pathways involved in raw ingredient transformation, connect them to resulting metabolites, and finally to their consequences on the fermented product, including technological, health and sensory aspects. Our work marks an improvement in the ambition of creating a harmonized semantic model for integrating different aspects of modern nutritional science. Such a model, besides formalizing a multifaceted knowledge, will be pivotal for a rich annotation of data in public repositories, as a prerequisite to generalized meta-analysis.

The present chapter provides a comprehensive overview of the multifaceted links connecting the immune system, the intestinal microbiota, and the diet, covering also some recent, less explored, and emerging topics such as the “trained immunity” and the immune cell metabolic activity. The main characteristics of the innate and adaptive immune system are described, as well as the gut-associated lymphoid tissue (GALT). Gut microbiota structure and function are also presented. Particular emphasis is given to the diet as a modulator of the microbiota-immune system crosstalk, focusing on the impact of the three main dietary components (carbohydrates, proteins, and fats) and the different dietary profiles on the gut microbiota, by shaping its composition and the deriving microbial metabolites that influence host health, also through interaction with the immune system. Western and Mediterranean diets are described and chosen as representative models of detrimental and beneficial dietary patterns, respectively.

A large subset of fermented foods act as vehicles of live environmental microbes, which often contribute food quality assets to the overall diet, such as health-associated microbial metabolites. Foodborne microorganisms also carry the potential to interact with the human gut microbiome via the food chain. However, scientific results describing the microbial flow connecting such different microbiomes as well as their impact on human health, are still fragmented. The aim of this systematic review is to provide a knowledge-base about the scientific literature addressing the connection between foodborne and gut microbiomes, as well as to identify gaps where more research is needed to clarify and map gut microorganisms originating from fermented foods, either traditional or added with probiotics, their possible impact on human gut microbiota composition and to which extent foodborne microbes might be able to colonize the gut environment. An additional aim was also to highlight experimental approaches and study designs which could be better standardized to improve comparative analysis of published datasets. Overall, the results presented in this systematic review suggest that a complex interplay between food and gut microbiota is indeed occurring, although the possible mechanisms for this interaction, as well as how it can impact human health, still remain a puzzling picture. Further research employing standardized and trans-disciplinary approaches aimed at understanding how fermented foods can be tailored to positively influence human gut microbiota and, in turn, host health, are therefore of pivotal importance.

Ageing is often characterised by nutritional deficiencies and functional alterations of the digestive and immune system. The aim of the present study was to analyse the impact of consumption of conventional milk with A1/A2 beta-casein, compared to milk containing only the A2 beta-casein variant, characterised by a protein profile favouring gut health. Twenty-four ageing Balb-c mice (20 months old) were fed for 4 weeks, with either a control diet (CTRL), a diet supplemented with bovine milk containing A1/A2 beta-casein (A1A2) or a diet containing A2/A2 beta-casein (A2A2). Lymphocyte subpopulations, enzymatic activities, cytokine secretion, gut morphology and histopathological alterations were measured in different gut segments, while short-chain fatty acids (SCFAs) content and microbiota composition were evaluated in faecal samples. The A2A2 group showed higher content of faecal SCFAs (in particular, isobutyrate) of intestinal CD4+ and CD19+ lymphocytes in the intraepithelial compartment and improved villi tropism. The A1A2 group showed higher percentages of intestinal TCRγδ+ lymphocytes. Faecal microbiota identified Deferribacteriaceae and Desulfovibrionaceae as the most discriminant families for the A2A2 group, while Ruminococcaceae were associated to the A1A2 group. Taken together, these results suggest a positive role of milk, in particular when containing exclusively A2 beta-casein, on gut immunology and morphology of an ageing mice model.

Purpose Several studies highlighted a correlation between folic acid deficiency and high plasma homocysteine concentration, considered a risk factor for multifactorial diseases. Natural folates represent an emerging alternative strategy to supplementation with synthetic folic acid, whose effects are controversial. The present work was, therefore, performed in hyperhomocysteinemic mice to study the impact of supplementation with dairy matrices containing natural folates on plasma homocysteine levels and faecal microbiota composition. Methods Forty mice were divided into six groups, two of which fed control or folic acid deficient (FD) diets for 10 weeks. The remaining four groups were fed FD diet for the first 5 weeks and then shifted to a standard control diet containing synthetic folic acid (R) or a FD diet supplemented with folate-enriched fermented milk (FFM) produced by selected lactic acid bacteria, fermented milk (FM), or milk (M), for additional 5 weeks. Results Supplementation with dairy matrices restored homocysteine levels in FD mice, although impacting differently on hepatic S -adenosyl-methionine levels. In particular, FFM restored both homocysteine and S -adenosyl-methionine levels to the control conditions, in comparison with FM and M. Next generation sequencing analysis revealed that faecal microbiota of mice supplemented with FFM, FM and M were characterised by a higher richness of bacterial species in comparison with C, FD and R groups. Analysis of beta diversity highlighted that the three dairy matrices determined specific, significant variations of faecal microbiota composition, while hyperhomocysteinemia was not associated with significant changes. Conclusions Overall, the results represent a promising starting point for the applicability of food matrices enriched in natural folates to manage hyperhomocysteinemia.

Lactic acid bacteria (LAB) are involved in several food fermentations and many of them provide strain-specific health benefits. Herein, the probiotic potential of the foodborne strain Lactobacillus fermentum MBC2 was investigated through in vitro and in vivo approaches. Caenorhabditis elegans was used as an in vivo model to analyze pro-longevity and anti-aging effects. L. fermentum MBC2 showed a high gut colonization capability compared to E. coli OP50 (OP50) or L. rhamnosus GG (LGG). Moreover, analysis of pumping rate, lipofuscin accumulation, and body bending showed anti-aging effects in L. fermentum MBC2-fed worms. Studies on PEPT-1 mutants demonstrated that pept-1 gene was involved in the anti-aging processes mediated by this bacterial strain through DAF-16, whereas the oxidative stress protection was PEPT-1 independent. Moreover, analysis of acid tolerance, bile tolerance, and antibiotic susceptibility were evaluated. L. fermentum MBC2 exerted beneficial effects on nematode lifespan, influencing energy metabolism and oxidative stress resistance, resulted in being tolerant to acidic pH and able to adhere to Caco-2 cells. Overall, these findings provide new insight for application of this strain in the food industry as a newly isolated functional starter. Furthermore, these results will also shed light on C. elegans molecular players involved in host-microbe interactions.

Probiotics exert beneficial effects on host health through different mechanisms of action, such as production of antimicrobial substances, competition with pathogens, enhancement of host mucosal barrier integrity and immunomodulation. In the context of ageing, which is characterized by several physiological alterations leading to a low grade inflammatory status called inflammageing, evidences suggest a potential prolongevity role of probiotics. Unraveling the mechanisms underlying anti-ageing effects requires the use of simple model systems. To this respect, the nematode Caenorhabditis elegans represents a suitable model organism for the study of both host-microbe interactions and for ageing studies, because of conserved signaling pathways and host defense mechanisms involved in the regulation of its lifespan. Therefore, this review analyses the impact of probiotics on C. elegans age-related parameters, with particular emphasis on oxidative stress, immunity, inflammation and protection from pathogen infections. The picture emerging from our analysis highlights that several probiotic strains are able to exert anti-ageing effects in nematodes by acting on common molecular pathways, such as insulin/insulin-like growth factor-1 (IIS) and p38 mitogen-activated protein kinase (p38 MAPK). In this perspective, C. elegans appears to be advantageous for shedding light on key mechanisms involved in host prolongevity in response to probiotics supplementation.

Table olives are increasingly recognized as a vehicle as well as a source of probiotic bacteria, especially those fermented with traditional procedures based on the activity of indigenous microbial consortia, originating from local environments. In the present study, we report characterization at the species level of 49 Lactic Acid Bacteria (LAB) strains deriving from Nocellara del Belice table olives fermented with the Spanish or Castelvetrano methods, recently isolated in our previous work. Ribosomal 16S DNA analysis allowed identification of 4 Enterococcus gallinarum, 3 E. casseliflavus, 14 Leuconostoc mesenteroides, 19 Lactobacillus pentosus, 7 L. coryniformis, and 2 L. oligofermentans. The L. pentosus and L. coryniformis strains were subjected to further screening to evaluate their probiotic potential, using a combination of in vitro and in vivo approaches. The majority of them showed high survival rates under in vitro simulated gastro-intestinal conditions, and positive antimicrobial activity against Salmonella enterica serovar Typhimurium, Listeria monocytogenes and enterotoxigenic Escherichia coli (ETEC) pathogens. Evaluation of antibiotic resistance to ampicillin, tetracycline, chloramphenicol, or erythromycin was also performed for all selected strains. Three L. coryniformis strains were selected as very good performers in the initial in vitro testing screens, they were antibiotic susceptible, as well as capable of inhibiting pathogen growth in vitro. Parallel screening employing the simplified model organism Caenorhabditis elegans, fed the Lactobacillus strains as a food source, revealed that one L. pentosus and one L. coryniformis strains significantly induced prolongevity effects and protection from pathogen-mediated infection. Moreover, both strains displayed adhesion to human intestinal epithelial Caco-2 cells and were able to outcompete foodborne pathogens for cell adhesion. Overall, these results are suggestive of beneficial features for novel LAB strains, which renders them promising candidates as starters for the manufacturing of fermented table olives with probiotic added value.

Lactobacillus delbrueckii represents a technologically relevant member of lactic acid bacteria, since the two subspecies bulgaricus and lactis are widely associated with fermented dairy products. In the present work, we report the characterization of two commercial strains belonging to L. delbrueckii subspecies bulgaricus, lactis and a novel strain previously isolated from a traditional fermented fresh cheese. A phenomic approach was performed by combining metabolomic and proteomic analysis of the three strains, which were subsequently supplemented as food source to the model organism Caenorhabditis elegans, with the final aim to evaluate their possible probiotic effects. Restriction analysis of 16S ribosomal DNA revealed that the novel foodborne strain belonged to L. delbrueckii subspecies lactis. Proteomic and metabolomic approaches showed differences in folate, aminoacid and sugar metabolic pathways among the three strains. Moreover, evaluation of C. elegans lifespan, larval development, brood size, and bacterial colonization capacity demonstrated that L. delbrueckii subsp. bulgaricus diet exerted beneficial effects on nematodes. On the other hand, both L. delbrueckii subsp. lactis strains affected lifespan and larval development. We have characterized three strains belonging to L. delbrueckii subspecies bulgaricus and lactis highlighting their divergent origin. In particular, the two closely related isolates L. delbrueckii subspecies lactis display different galactose metabolic capabilities. Moreover, the L. delbrueckii subspecies bulgaricus strain demonstrated potential probiotic features. Combination of omic platforms coupled with in vivo screening in the simple model organism C. elegans is a powerful tool to characterize industrially relevant bacterial isolates.

Background: Obesity is a complex pathology associated with dysbiosis, metabolic alterations, and low-grade chronic inflammation promoted by immune cells, infiltrating and populating the adipose tissue. Probiotic supplementation was suggested to be capable of counteracting obesity-associated immune and microbial alterations, based on its proven immunomodulatory activity and positive effect on gut microbial balance. Traditional fermented foods represent a natural source of live microbes, including environmental strains with probiotic features, which could transiently colonise the gut. The aim of our work was to evaluate the impact of supplementation with a complex foodborne bacterial consortium on obesity-associated inflammation and gut microbiota composition in a mouse model. Methods: C57BL/6J mice fed a 45% high fat diet (HFD) for 90 days were supplemented with a mixture of foodborne lactic acid bacteria derived from the traditional fermented dairy product "Mozzarella di Bufala Campana" (MBC) or with the commercial probiotic GG strain of Lactobacillus rhamnosus (LGG). Inflammation was assessed in epididymal white adipose tissue (WAT) following HFD. Faecal microbiota composition was studied by next-generation sequencing. Results: Significant reduction of epididymal WAT weight was observed in MBC-treated, as compared to LGG and control, animals. Serum metabolic profiling showed correspondingly reduced levels of triglycerides and higher levels of HDL cholesterol, as well as a trend toward reduction of LDL-cholesterol levels. Analysis of the principal leucocyte subpopulations in epididymal WAT revealed increased regulatory T cells and CD4(+) cells in MBC microbiota-supplementedmice, as well as decreased macrophage and CD8(+) cell numbers, suggesting anti-inflammatory effects. These results were associated with lower levels of pro-inflammatory cytokines and chemokines in WAT explants. Faecal bacterial profiling demonstrated increased Firmicutes/Bacteroidetes ratio in all mice groups following HFD. Conclusions: Taken together, these results indicate a protective effect of MBC microbiota supplementation toward HFD-induced fat accumulation and triglyceride and cholesterol levels, as well as inflammation, suggesting a stronger effect of a mixed microbial consortium vs single-strain probiotic supplementation. The immunomodulatory activity exerted by the MBC microbiota could be due to synergistic interactions within the microbial consortium, highlighting the important role of dietary microbes with yet uncharacterised probiotic effect.

Table olives are widely consumed worldwide but, due to the presence of NaCl in fermenting brines, they contain high levels of sodium. A promising strategy to lower sodium content is the reduction or substitution of NaCl in brines with other chlorides. However, these procedures may impact safety, spoilage, as well as quality and technological properties, including the evolution and final composition of the fermenting microbiota. In the present work the effects of partially replacing NaCl with KCl in fermenting brines on the microbiological quality of Nocellara del Belice olives produced by Spanish style (Sivigliano) or Castelvetrano methods have been analyzed. In both cases, the fermentation steps were performed in parallel, in brines containing either NaCl alone, or partially replaced with different proportions of KCl (25, 50 and 75%), while maintaining a final saline concentration of 9% (Sivigliano method) or 7% (Castelvetrano). To compare microbial dynamics in the experimental brines, changes in bacterial ecology were monitored during fermentation with a polyphasic approach, including both microbiological methods and culture-independent techniques based on DGGE and NGS analysis. The main microbial groups detected in the olive microbiota from both production procedures were LAB and yeasts. Overall, the data demonstrate that partial replacement of NaCl with KCl does not increase the risk of contamination, nor the overgrowth of pathogens or spoiler microbes.