The potential probiotic properties of Limosilactobacillus fermentum Lf2, an exopolysaccharide (EPS)-producing strain, were assessed in C57BL/6 mice. The aim of this work was to elucidate if these properties could be associated with the ability to produce EPSs. Mice were divided into three treatments: L (mice treated with Lf2), E (animals that received EPSs), and C (control group). The levels of fecal acetic and propionic acids significantly increased in L and E compared with C. Catalase activity increased in L in comparison with the other groups in the liver and small intestine. The enzyme activities of superoxide dismutase and glutathione S-transferase increased in the large intestine for L compared with C. In addition, in the large intestine, the concentration of TNF-α was reduced in L and E in comparison with C. In the small intestine, TNF-α, IFN-γ, IL-12, and IL-6 presented lower levels in L and E than C. The analysis of the gut microbiota showed that L presented higher levels of Peptococcaceae and Rikenellaceae, while E had higher levels of Peptococcaceae than C. Overall, these results provide new insights into the relationship between the probiotic properties of lactic acid bacteria and their ability to produce EPSs.

Common factors influencing the survival of microbes to spray drying include microbial intrinsic resistance, properties of the carrier, inlet and outlet temperatures, and rate of feeding. In this work, cheese whey was used as both a growth medium and a carrier for spray drying of Bifidobacterium animalis subsp. lactis INL1. The growth of the strain was favoured by acid conditions, reaching higher counts when pH was not controlled during fermentation and when pH was controlled at a constant value of 5.5, compared with 6.5. Powders containing ca. 9 log order (cfu/g) of B. lactis INL1 were obtained by direct spray drying of the culture coming out of the fermenter. No differences in survival to spray drying were observed in terms of fermentation conditions. However, fermentation conditions are considered to have influenced the strain's survival along the storage. Spray drying in acid conditions was detrimental to the survival along storage.

Limosilactobacillus fermentum Lf2 (Lf2) is an autochthonous strain that produces high levels of exopolysaccharides (EPS). The objective of this work was to evaluate the probiotic potential of Lf2 and its relationship with these metabolites in a mouse model of TNBS (trinitrobenzene sulfonic acid)-induced chronic colitis. Mice were treated intrarectally with increasing doses of TNBS resuspended in 50% ethanol for 14 days. In parallel, they received different treatments by gavage (lactose 10% as the matrix): freeze-dried Lf2 (L); purified EPS (E); and lactose 10% (T). A healthy control group (H) was treated with 50% alcohol without TNBS (intrarectally) and 10% lactose (by gavage). In the small intestine, there was a significant increase in IgA levels for the group that received EPS and a decrease in IFN-γ for mice treated with the strain compared to the other groups. In the large intestine, IL-2 and IFN-γ presented the lowest levels in the groups treated with EPS and the strain. The concentrations of acetic and propionic acids in mice that received Lf2 were the highest, while the levels of butyric acid were comparable to the healthy control group. An increase in the abundance of SCFA-producing bacteria was observed for mice treated with EPS and the strain in comparison with the colitis control group. The enzyme activity of catalase was higher in all the treatments compared to the TNBS-induced colitis control mice. To summarize the results obtained, a principal component analysis (PCA) was performed, clearly grouping the treatments in different clusters according to the variables studied. This is one of the first studies to address the role of a potential probiotic strain in a chronic colitis mouse model, trying to elucidate the relationship between its properties and the EPS synthesized.

Forty obligate heterofermentative lactic acid bacilli (HB) isolated from dairy environment as non-starter lactic acid bacteria (NSLAB) were studied regarding their potential as novel starter cultures for fermented foods. Preliminary genotipic and phenotypic tests allowed the selection of 16 strains, identified as Limosilactobacillus fermentum (12 strains), Levilactobacillus brevis (2), Lentilactobacillus buchneri (1) and Weissella confusa (1). They were initially studied at the technological level, focusing on stress factors (low temperature, heat, salt and acidic media), growth in milk, viability after freezing and thawing and growth in cereal-based matrices. Based on this, six strains were chosen for further studies: L. brevis (LB61 and LB66), L. buchneri (LBu39), L. fermentum (LF22 and LF68) and W. confusa (W20). The selected strains grew well in wheat and gluten-free (GF) doughs, produced exopolysaccharides, acetic and lactic acid in a ratio (<1:5) that allowed the inhibition of undesirable organisms without causing off-flavours, and had good salt resistance. Among them, Weissella confusa W20 was used as starter culture for sourdough fermentation to manufacture gluten-free breads, showing noticeable improvements at the organoleptic level in comparison to GF breads fermented only with yeast. This work remarks the importance of studying the potential of wild strains to find alternative matrices beyond those from where they were isolated. With this regard, our investigation allowed the selection of six dairy strains with potential as starter cultures for bread making, which reaffirms that allochthonous strains can be suitable for sourdough preparation.

To study (16S rRNA-sequencing) the impact of gestational and corrected ages on the microbiota profile of human milk (HM) of mothers that delivered full-term and pre-term children, HM samples were obtained and classified according to the gestational age as group T (full-term births ≥37 weeks), and group P (pre-term births <37 weeks). Group P was longitudinally followed, and the samples were collected at the full-term corrected gestational age: when the chronological age plus the gestational age were ≥37 weeks (PT group). The HM microbiota composition differed depending on the gestational age (T vs. P). Group T had lower levels of Staphylococcus and higher levels of Rothia and Streptococcus, as compared to group P. The alpha Simpson diversity value was higher in group T than in P, whereas no differences were found between groups T and PT, suggesting a microbial evolution of the composition of group P towards group T over chronological age. Full-term delivery was associated with a greater diversity of microbes in HM. The microbial composition of pre-term HM, at the corrected age, did not show significant differences, as compared to the samples obtained from the full-term group, suggesting that it would be appropriate to consider the corrected age in terms of the composition and the diversity of the milk in future studies.

The human microbiome is an integral component of the human body and a co-determinant of several health conditions 1 , 2 . However, the extent to which interpersonal relations shape the individual genetic makeup of the microbiome and its transmission within and across populations remains largely unknown 3 , 4 . Here, capitalizing on more than 9,700 human metagenomes and computational strain-level profiling, we detected extensive bacterial strain sharing across individuals (more than 10 million instances) with distinct mother-to-infant, intra-household and intra-population transmission patterns. Mother-to-infant gut microbiome transmission was considerable and stable during infancy (around 50% of the same strains among shared species (strain-sharing rate)) and remained detectable at older ages. By contrast, the transmission of the oral microbiome occurred largely horizontally and was enhanced by the duration of cohabitation. There was substantial strain sharing among cohabiting individuals, with 12% and 32% median strain-sharing rates for the gut and oral microbiomes, and time since cohabitation affected strain sharing more than age or genetics did. Bacterial strain sharing additionally recapitulated host population structures better than species-level profiles did. Finally, distinct taxa appeared as efficient spreaders across transmission modes and were associated with different predicted bacterial phenotypes linked with out-of-host survival capabilities. The extent of microorganism transmission that we describe underscores its relevance in human microbiome studies 5 , especially those on non-infectious, microbiome-associated diseases.

BACKGROUND:Four commercial starter cultures containing Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus (S1, S2, S3 and S4; S3 also contained Limosilactobacillus fermentum) were compared for fermentation, volatile flavor compounds, physicochemical parameters and microbiology, in yogurt prepared from three milk base formulations with increased protein (B1, B2 and B3).RESULTS:The fermentation patterns differed among starters, with Yoflex Mild 1.0 (S4) and SLB95 (S2) showing the longest fermentation time, depending on the formulation. At 21 days, S. thermophilus counts were similar among starters and higher than 8.52 log CFU mL-1 , for all yogurts. The highest counts (6.86 log CFU mL-1 ) for L. delbrueckii subsp. bulgaricus was found for S2 yogurts made from whey protein hydrolysate (B3). Minor water-holding capacity was detected for YF-L811 (S1) yogurts. Yoflex Harmony 1.0 (S3) starter containing Lim. fermentum produced a distinctive volatile profile characterized by aldehydes with respect to yogurts prepared with S1, S2 and S4, which were characterized by ketones.CONCLUSION:Results indicate the usefulness of carrying out studies similar to the present one to select the most appropriate process conditions depending on the desired product. © 2022 Society of Chemical Industry.

Limosilactobacillus fermentum Lf2 (Lf2) and Bifidobacterium animalis INL1 (INL1) are two autochthonous probiotic strains that produce exopolysaccharides (EPS), and some of these molecules were associated with health-promoting properties. In the present work, stirred yoghurts supplemented with these bacteria (added before or after fermentation) were made, in parallel with yoghurt with purified EPS from Lf2. The rheological properties, water holding capacity, microstructure, metabolic activity (aminopepti-dase activity, sugar and organic acid metabolism), and production of bioactive peptides (before and after in vitro digestion) were assessed, as well as the activities of six peptidases for each strain, the latter clearly showing different patterns. Yoghurts made with starter culture and Lf2 exhibited a major impact on the previously mentioned parameters. In conclusion, both EPS-producing microorganisms increased the release of bioactive metabolites in yoghurt; they also impacted on levels of organic acids and car-bohydrates, rheological properties, and microstructure.(c) 2022 Elsevier Ltd. All rights reserved.

Domesticated horses live under different conditions compared with their extinct wild ancestors. While housed, medicated and kept on a restricted source of feed, the microbiota of domesticated horses is hypothesized to be altered. We assessed the fecal microbiome of 57 domestic and feral horses from different locations on three continents, observing geographical differences. A higher abundance of eukaryota ( p < 0.05) and viruses ( p < 0.05) and lower of archaea ( p < 0.05) were found in feral animals when compared with domestic ones. The abundance of genes coding for microbe-produced enzymes involved in the metabolism of carbohydrates was significantly higher ( p < 0.05) in feral animals regardless of the geographic origin. Differences in the fecal resistomes between both groups of animals were also noted. The domestic/captive horse microbiomes were enriched in genes conferring resistance to tetracycline, likely reflecting the use of this antibiotic in the management of these animals. Our data showed an impoverishment of the fecal microbiome in domestic horses with diet, antibiotic exposure and hygiene being likely drivers. The results offer a view of the intestinal microbiome of horses and the impact of domestication or captivity, which may uncover novel targets for modulating the microbiome of horses to enhance animal health and well-being.

Lockdown and social distancing due to COVID-19 affected the mental health and lifestyle of the population. However, there is insufficient evidence of alterations in eating behavior. Our study seeks to describe the relationship between eating behavior and eating habits among Chilean adults during the confinement period. A sample of 760 Chilean subjects was analyzed, who answered surveys using Google Forms, considering demographic characteristics, social distancing, dietary habits and EB. More than half of the participants consider that their dietary intake increased during confinement. Changes in dietary intake were analyzed according to food group, and a decrease in the consumption of fish, fruits and dairy pro- ducts was observed, while legumes, processed foods and soft drinks showed an increase, which represents risk factors for the development of cardiovascular diseases. When analyzing eating behavior, a greater difficulty in stopping eating was observed when faced with external stimuli; increased intake associated with complex emotional situations, and when isolating the group that decreased their intake of unhealthy foods, a greater ability to limit their intake for weight control was reported. Our results are similar to other studies, and they reinforce that confinement is related to eating behavior, leading to changes in eating habits, which indicates that, at the public health level, post-pandemic nutritional strategies, should be focused on regulating eating behavior in order to guide habits towards healthy eating. Keywords: COVID-19; Dietary intake; Eating behavior; Food intake; Lockdown.

To characterize the fermentation process and bacterial diversity of sorghum silage inoculated with Lactiplantibacillus plantarum LpAv, Pediococcus pentosaceus PpM and Lacticaseibacillus paracasei LcAv.

EDITORIAL article Front. Microbiol., 01 November 2021Sec. Food Microbiology https://doi.org/10.3389/fmicb.2021.780596

Microbial food alterations lead to unfit products for consumption, and their discarding, to significant economic losses for the food industry. During storage, fresh foods offer available niches for the survival and growth of undesirable microorganisms. In dairy products, data regarding spoilage and/or pathogenic bacteria is better documented than those for molds and yeasts. Dairy products are less susceptible to mold's contamination than products such as fruits and vegetables, due to their refrigerated storage; their elaboration from heat-treated milk and, for fermented ones, the dominant microbiota that acidifies the medium. However, even cheeses and yogurts may be susceptible to mold contamination. Atypical cases of yogurt samples containing spoilage microorganisms not previously reported (molds producing gas and bacteria of the genus Gluconobacter) in Argentinean fermented milks are presented here. For yogurt, in particular, the "classic" altering organisms were always being yeasts, and in other countries, molds belonging to the genus Aspergillus.

Elderly people are an important part of the global population who suffer from the natural processes of senescence, which lead to changes in the gut microbiota composition. These modifications have a great impact on their quality of life, bringing a general putrefactive and inflammatory status as a consequence. Some of the most frequent conditions related to this status are constipation, undernutrition, neurodegenerative diseases, susceptibility to opportunistic pathogens, and metabolic disbalance, among others. For these reasons, there is an increasing interest in improving their quality of life by non-invasive treatments such as the consumption of probiotics, prebiotics, and synbiotics. The aim of the present mini-review is to describe the benefits of these functional supplements/food according to the most recent clinical and pre-clinical studies published during the last decade. In addition, insights into several aspects we consider relevant to improve the quality of future studies are provided.

Breast milk can be a source of potential probiotic bacteria, but the technological capacity of isolates obtained from this source is not always guaranteed. We aimed at isolating lactobacilli from breast milk samples collected in Argentina, focusing on isolates with functional and technological potential as probiotics. Fourteen Lactobacillus and one Bifidobacterium isolates were obtained from 164 samples donated by 104 mothers. The isolates preliminarily identified by MALDI-TOF, and then the identity was confirmed by partial 16S rRNA gene sequencing. Hydrophobicity was determined (hexadecane and xylene partition). The strains were also co-cultured with murine RAW 264.7 macrophages for screening the capacity to induce the anti-inflammatory cytokine interleukin (IL)-10. Hydrophobicity ranged from 7.4 and 95.9%. The strains Lactobacillus gasseri (70a and 70c) and Lactobacillus plantarum (73a and 73b) were the strains with a higher capacity to induce IL-10 production by macrophages. The technological application was evaluated by freezing dried in 10% lactose or 10% polydextrose. The survival was assessed after accelerated (37 °C, 4 weeks) or long-term (5 and 25 °C, 12 months) storage. Except for Lactobacillus gallinarum 94d, strains lost less than 1 Log10 order cfu/g after long-term (12 months) storage at 5 °C in lactose and polydextrose as protectants. A low correlation between survival to accelerated and long-term storage tests was observed. L. gasseri (70a and 70c) and L. plantarum (73a and 73b) deserve further studies as potential probiotics due to their capacity to induce IL-10 from murine macrophages and their hydrophobicity. In special, L. plantarum 73a was able to confer enhanced protection against Salmonella infection by promoting the immunity of the small intestine.

Exopolysaccharides (EPS) production is a characteristic that has been widely described for many lactic acid bacteria (LAB) of different genera and species, but little is known about the relationship between the functional properties of the producing bacteria and EPS synthesis. Although many studies were addressed towards the application of EPS-producing LAB in the manufacture of several dairy products (fermented milk, cheese) due to their interesting technological properties (increased hardness, water holding capacity, viscosity, etc.), there are not many reports about the functional properties of the EPS extract itself, especially for the genus Lactobacillus. The aim of the present revision is to focus on the species Lactobacillus fermentum with reported functional properties, with particular emphasis on those strains capable of producing EPS, and try to establish if there is any linkage between this property and their functional/probiotic roles, considering the most recent bibliography.

We aimed at isolating lactic acid bacteria (LAB) from different plant materials to study their crossed-fermentation capacity in silos and to find strains able to confer enhanced aerobic stability to silage. A total of 129 LAB isolates were obtained from lucerne (alfalfa), maize, sorghum, ryegrass, rice, barley, canola, Gatton panic, Melilotus albus, soy, white clover, wheat, sunflower, oat, and moha. Four Lactiplantibacillus plantarum subsp. plantarum strains (isolated from oat, lucerne, sorghum, or maize) were selected for their growth capacity. Identity (16S sequencing) and diversity (RAPD-PCR) were confirmed. Fermentative capacity (inoculated at 104, 105, 106, 107 CFU/g) was studied in maize silage and their cross-fermentation capacity was assessed in oat, lucerne, sorghum, and maize. Heterofermentative strains with the highest acetic acid production capacity conferred higher aerobic stability to maize silages. Regardless the source of isolation, L. plantarum strains, inoculated at a rate of 106 CFU/g, were effective to produce silage from different plant materials. From more than 100 isolates obtained, the application of a succession of experiments allowed us to narrow down the number of potential candidates of silage inoculants to two strains. Based on the studies made, L. plantarum LpM15 and Limosilactobacillus fermentum LfM1 showed potential to be used as inoculants, however further studies are needed to determine their performance when inoculated together. The former because it positively influenced different quality parameters in oat, lucerne, sorghum, and maize silage, and the latter because of its capacity to confer enhanced aerobic stability to maize silage. The rest of the strains constitute a valuable collection of autochthonous strains that will be further studied in the future for new applications in animal or human foods.