Fermentation of non-digestible raffinose family oligosaccharides and galactomannans by probiotics

Determinants of raffinose family oligosaccharide use in Bacteroides species

Bacteroides species are successful colonizers of the human gut and can utilize a wide variety of complex polysaccharides and oligosaccharides that are indigestible by the host. To do this, they use enzymes encoded in Polysaccharide Utilization Loci (PULs). While recent work has uncovered the PULs required for use of some polysaccharides, how Bacteroides utilize smaller oligosaccharides is less well studied. Raffinose family oligosaccharides (RFOs) are abundant in plants, especially legumes, and consist of variable units of galactose linked by α-1,6 bonds to a sucrose (glucose α-1-β-2 fructose) moiety. Previous work showed that an α-galactosidase, BT1871, is required for RFO utilization in Bacteroides thetaiotaomicron. Here, we identify two different types of mutations that increase BT1871 mRNA levels and improve B. thetaiotaomicron growth on RFOs. First, a novel spontaneous duplication of BT1872 and BT1871 places these genes under control of a ribosomal promoter, driving high BT1871 transcription. Second, nonsense mutations in a gene encoding the PUL24 anti-sigma factor likewise increase BT1871 transcription. We then show that hydrolases from PUL22 work together with BT1871 to break down the sucrose moiety of RFOs and determine that the master regulator of carbohydrate utilization (BT4338) plays a role in RFO utilization in B. thetaiotaomicron. Examining the genomes of other Bacteroides species, we found homologs of BT1871 in subset and show that representative strains of species containing a BT1871 homolog grew better on melibiose than species that lack a BT1871 homolog. Altogether, our findings shed light on how an important gut commensal utilizes an abundant dietary oligosaccharide.

Enhancing nutritional and sensory properties of plant-based beverages: a study on chickpea and Kamut® flours fermentation using Lactococcus lactis

The study aimed to set up a protocol for the production of a clean-label plant-based beverage (PBB), obtained by mixing chickpeas and Kamut® flours and using a commercial Lactococcus lactis (LL) as fermentation starter, and to characterize it, from nutritional, microbiological, textural, shelf-life, and sensory points of view. The effect of using the starter was evaluated comparing the LL-PBB with a spontaneously fermented beverage (CTRL-PBB). Both PBBs were high in proteins (3.89/100 g) and could be considered as sources of fiber (2.06/100 g). Notably, L. lactis fermentation enhanced the phosphorus (478 vs. 331 mg/kg) and calcium (165 vs. 117 mg/kg) concentrations while lowering the raffinose content (5.51 vs. 5.08 g/100 g) compared to spontaneous fermentation. Cell density of lactic acid bacteria increased by ca. two log cycle during fermentation of LL-PBB, whereas undesirable microbial groups were not detected. Furthermore, L. lactis significantly improved the beverage's viscosity (0.473 vs. 0.231 Pa s), at least for 10 days, and lightness. To assess market potential, we conducted a consumer test, presenting the LL-PBB in "plain" and "sweet" (chocolate paste-added) variants. The "sweet" LL-PBB demonstrated a higher acceptability score than its "plain" counterpart, with 88 and 78% of participants expressing acceptability and a strong purchase intent, respectively. This positive consumer response positions the sweet LL-PBB as a valuable, appealing alternative to traditional flavored yogurts, highlighting its potential in the growing plant-based food market.

Isolation and structural elucidation of prebiotic oligosaccharides from Ziziphi Spinosae Semen

Six oligosaccharides were discovered and isolated for the first time from Ziziphi Spinosae Semen. On the basis of spectroscopic analysis, their structures were determined to be verbascose (1), verbascotetraose (2), stachyose (3), manninotriose (4), raffinose (5), and melibiose (6). The prebiotic effect of the oligosaccharide fraction was assayed by eight gut bacterial growth in vitro, revealing a significant increase in cell density, up to 4-fold, for Lactobacillus acidophilus, Lactobacillus gasseri, and Lactobacillus johnsonii. The impact of six oligosaccharides with different degrees of polymerization (DPs) and structures on the growth of Lactobacillus acidophilus was evaluated. As a result, stachyose and raffinose demonstrated superior support for bacterial growth compared to the other oligosaccharides. This study explored the structure-activity relationship of raffinose family oligosaccharides (RFOs) and showed that the more the monosaccharide type, the more supportive the gut bacteria growth when oligosaccharides have the same molecular weight.

Toxic cyanobacteria induce coupled changes in gut microbiota and co-metabolite of freshwater gastropods

Frequent outbreaks of harmful cyanobacterial blooms and the microcystins (MCs) they produce seriously affect the survival of aquatic organisms. Interactions between gut microbiota and hosts often play crucial roles in driving the adaptation of aquatic organisms to environmental changes. In this study, we investigated the phenotypic indicators of the freshwater gastropod Bellamya aeruginosa, after uptake of Microcystis aeruginosa and explored its gut microbial composition and gut metabolites in response to toxic cyanobacterial stress. Results showed that the MCs concentration in the hepatopancreas of snails fed with toxic cyanobacteria decreased from 2.64 ± 0.14 μg·g-1 on day 7 to 1.16 ± 0.10 μg·g-1 on day 14. The compositions of the intestinal microbiota of snails fed with different algae significantly differed, and the relative abundance of gut microbes such as Lactobacillus and Sphingobium significantly increased after feeding toxic cyanobacteria. Significant differences also existed in intestinal metabolites, the relative abundance of the following metabolites significantly increased: l-proline, 5,6-DHET, stachyose, raffinose, and 3-isopropylmalate. Sankey network diagrams showing links between gut microbes and gut metabolites. The association of Lactobacillus and Sphingobium with amino acids may be related to host tolerance to toxicity, and the linkages of gut microbes with metabolites such as levan, imidazolepropionic acid, and eicosanoids may be associated with involvement in host immune responses. The association of microbes with stachyose and raffinose can help the host to regulate energy homeostasis. These results reveal the underlying mechanisms of gut microbes in the snail adaptation to toxic cyanobacterial stress. This study could be great important for gaining new insights into toxic cyanobacteria-induced changes in snail gut microbes and metabolites and their roles in snail adaptation to toxic cyanobacterial stress, and may provide important insights into the use of freshwater gastropods for the prevention and control of cyanobacterial blooms.

Characterization of Carbohydrates, Amino Acids, Viscosity, and Antioxidant Capacity in Rice Wines Made in Saitama, Japan, with Different Sake Rice

We investigated the physicochemical properties of Japanese rice wines, including their functional properties and carbohydrate and amino acid content in solution and solid state. Three samples were tested. The glucose, allose, and raffinose contents in samples (A, B, C) in g/100 g were (3.47, 3.45, 7.05), (1.60, 1.63, 1.61), and (2.14, 2.75, 1.49), respectively. The total amino acid in µmol/mL was (3.1, 3.5, 4.4). Glutamic acid, alanine, and arginine varied in content across the samples. The viscosity (10 °C) and activation energy (ΔE) calculated using the Andrade equation were (2.81 ± 0.03, 2.74 ± 0.06, 2.69 ± 0.03) mPa-s and (22.3 ± 1.1, 22.0 ± 0.2, 21.3 ± 0.5) kJ/mol, respectively. Principal component analysis using FT-IR spectra confirmed the separation of the samples into principal components 2 and 3. The IC50 values from the DPPH radical scavenging test were (2364.7 ± 185.3, 3041.9 ± 355.1, 3842.7 ± 228.1) µg/mL. Thus, the three rice wines had different carbohydrate and amino acid contents, viscosities, and antioxidant capacities.

A comprehensive metabolomics and lipidomics atlas for the legumes common bean, chickpea, lentil and lupin

Legumes represent an important component of human and livestock diets; they are rich in macro- and micronutrients such as proteins, dietary fibers and polyunsaturated fatty acids. Whilst several health-promoting and anti-nutritional properties have been associated with grain content, in-depth metabolomics characterization of major legume species remains elusive. In this article, we used both gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) to assess the metabolic diversity in the five legume species commonly grown in Europe, including common bean (Phaseolus vulgaris), chickpea (Cicer arietinum), lentil (Lens culinaris), white lupin (Lupinus albus) and pearl lupin (Lupinus mutabilis), at the tissue level. We were able to detect and quantify over 3400 metabolites covering major nutritional and anti-nutritional compounds. Specifically, the metabolomics atlas includes 224 derivatized metabolites, 2283 specialized metabolites and 923 lipids. The data generated here will serve the community as a basis for future integration to metabolomics-assisted crop breeding and facilitate metabolite-based genome-wide association studies to dissect the genetic and biochemical bases of metabolism in legume species.

Biotransformation of Tyrosol into a Novel Valuable α-Galactoside with Increased Solubility and Improved Anti-inflammatory Activities

Herein, tyrosol [2-(4-hydroxyphenyl) ethanol], which is rich in olive oil and red wine, was converted to a novel bioactive galactoside by enzymic glycosylation. The gene of α-galactosidase from Geobacillus stearothermophilus 23 was cloned and expressed in Escherichia coli as catalytically active inclusion bodies. The catalytically active inclusion bodies efficiently catalyzed the galactosylation of tyrosol using either melibiose or raffinose family oligosaccharides as glycosyl donors, resulting in a glycoside with 42.2 or 14.2% yields. The glycoside product was purified and identified as p-hydroxyphenethyl α-d-galactopyranoside by mass spectrometry and NMR analyses. The inclusion bodies can be recycled and reused for at least 10 batch reactions of galactoside synthesis. Moreover, the galactoside showed 11-fold increased water solubility and reduced cytotoxicity as compared to tyrosol. Also, it exhibited higher antioxidative and anti-inflammatory activities than tyrosol based on lipopolysaccharide-induced activated BV2 cells. These results provided important insights into the application of tyrosol derivatives in functional foods.

Optimizing raffinose family oligosaccharides content in plants: A tightrope walk

Plants synthesize various compounds for their growth, metabolism, and stress mitigation, and one such group of compounds is the raffinose family of oligosaccharides (RFOs). RFOs are non-reducing oligosaccharides having galactose residues attached to a sucrose moiety. They act as carbohydrate reserves in plants, assisting in seed germination, desiccation tolerance, and biotic/abiotic stress tolerance. Although legumes are among the richest sources of dietary proteins, the direct consumption of legumes is hindered by an excess of RFOs in the edible parts of the plant, which causes flatulence in humans and monogastric animals. These opposing characteristics make RFOs manipulation a complicated tradeoff. An in-depth knowledge of the chemical composition, distribution pattern, tissue mobilization, and metabolism is required to optimize the levels of RFOs. The most recent developments in our understanding of RFOs distribution, physiological function, genetic regulation of their biosynthesis, transport, and degradation in food crops have been covered in this review. Additionally, we have suggested a few strategies that can sustainably reduce RFOs in order to solve the flatulence issue in animals. The comprehensive information in this review can be a tool for researchers to precisely control the level of RFOs in crops and create low antinutrient, nutritious food with wider consumer acceptability.

Probiotic Potential and Safety Assessment of Type Strains of Weissella and Periweissella Species

Although numerous strains belonging to the Weissella genus have been described in the last decades for their probiotic and biotechnological potential, others are known to be opportunistic pathogens of humans and animals. Here, we investigated the probiotic potential of two Weissella and four Periweissella type strains belonging to the species Weissella diestrammenae, Weissella uvarum, Periweissella beninensis, Periweissella fabalis, Periweissella fabaria, and Periweissella ghanensis by genomic and phenotypic analyses, and performed a safety assessment of these strains. Based on the results of the survival to simulated gastrointestinal transit, autoaggregation and hydrophobicity characteristics, as well as adhesion to Caco-2 cells, we showed that the P. beninensis, P. fabalis, P. fabaria, P. ghanensis, and W. uvarum type strains exhibited a high probiotic potential. The safety assessment, based on the genomic analysis, performed by searching for virulence and antibiotic resistance genes, as well as on the phenotypic evaluation, by testing hemolytic activity and antibiotic susceptibility, allowed us to identify the P. beninensis type strain as a safe potential probiotic microorganism. IMPORTANCE A comprehensive analysis of safety and functional features of six Weissella and Periweissella type strains was performed. Our data demonstrated the probiotic potential of these species, indicating the P. beninensis type strain as the best candidate based on its potential probiotic features and the safety assessment. The presence of different antimicrobial resistance profiles in the analyzed strains highlighted the need to establish cutoff values to perform a standardized safety evaluation of these species, which, in our opinion, should be mandatory on a strain-specific basis.

Intracellular glycogen accumulation by human gut commensals as a niche adaptation trait

The human gut microbiota is a key contributor to host metabolism and physiology, thereby impacting in various ways on host health. This complex microbial community has developed many metabolic strategies to colonize, persist and survive in the gastrointestinal environment. In this regard, intracellular glycogen accumulation has been associated with important physiological functions in several bacterial species, including gut commensals. However, the role of glycogen storage in shaping the composition and functionality of the gut microbiota offers a novel perspective in gut microbiome research. Here, we review what is known about the enzymatic machinery and regulation of glycogen metabolism in selected enteric bacteria, while we also discuss its potential impact on colonization and adaptation to the gastrointestinal tract. Furthermore, we survey the presence of such glycogen biosynthesis pathways in gut metagenomic data to highlight the relevance of this metabolic trait in enhancing survival in the highly competitive and dynamic gut ecosystem.

Synergy between oligosaccharides and probiotics: From metabolic properties to beneficial effects

Synbiotic is defined as the dietary mixture that comprises both probiotic microorganisms and prebiotic substrates. The concept has been steadily gaining attention owing to the rising recognition of probiotic, prebiotics, and gut health. Among prebiotic substances, oligosaccharides demonstrated considerable health beneficial effects in varieties of food products and their combination with probiotics have been subjected to full range of evaluations. This review delineated the landscape of studies using microbial cultures, cell lines, animal model, and human subjects to explore the functional properties and host impacts of these combinations. Overall, the results suggested that these combinations possess respective metabolic properties that could facilitate beneficial activities therefore could be employed as dietary interventions for human health improvement and therapeutic purposes. However, uncertainties, such as applicational practicalities, underutilized analytical tools, contradictory results in studies, unclear mechanisms, and legislation hurdles, still challenges the broad utilization of these combinations. Future studies to address these issues may not only advance current knowledge on probiotic-prebiotic-host interrelationship but also promote respective applications in food and nutrition.

Context-dependent differences in the functional responses of Lactobacillaceae strains to fermentable sugars

Lactobacillaceae are Gram-positive rods, facultative anaerobes, and belong to the lactic acid bacteria (LAB) that frequently serve as probiotics. We systematically compared five LAB strains for the effects of different carbohydrates on their free-living and biofilm lifestyles. We found that fermentable sugars triggered an altered carrying capacity with strain specificity during planktonic growth. In addition, heterogeneous response to fermentable sugar was manifested in microbial aggregation (measured by imaging flow cytometry), colony development, and attachment to mucin. The acid production capacities of the strains were compatible and could not account for heterogeneity in their differential carrying capacity in liquid and on a solid medium. Among tested LAB strains, L. paracasei, and L. rhamnosus GG survived self-imposed acid stress while L. acidophilus was extremely sensitive to its own glucose utilization acidic products. The addition of a buffering system during growth on a solid medium significantly improved the survival of most tested probiotic strains during fermentation, but the formation of biofilms and aggregation capacity were responsive to the carbohydrate provided rather than to the acidity. We suggest that the optimal performance of the beneficial microbiota members belonging to Lactobacillaceae varies as a function of the growth model and the dependency on a buffering system.

EDESIA: Plants, Food and Health: A cross-disciplinary PhD programme from crop to clinic

In an era where preventive medicine is increasingly important due to an ageing population and rising obesity, optimised diets are key to improving health and reducing risk of ill health. The Wellcome Trust-funded, EDESIA: Plants, Food and Health: a cross-disciplinary PhD programme from Crop to Clinic (218 467/Z/19/Z) focuses on investigating plant-based nutrition and health, from crop to clinic, drawing on the world-class interdisciplinary research expertise of partner institutions based on the Norwich Research Park (University of East Anglia, John Innes Centre, Quadram Institute and Earlham Institute). Through a rotation-based programme, EDESIA PhD students will train in a wide range of disciplines across the translational pathway of nutrition research, including analyses of epidemiological datasets, assessment of nutritional bioactives, biochemical, genetic, cell biological and functional analyses of plant metabolites, in vitro analyses in tissue and cell cultures, investigation of efficacy in animal models of disease, investigation of effects on composition and functioning of the microbiota and human intervention studies. Research rotations add a breadth of knowledge, outside of the main PhD project, which benefits the students and can be brought into project design. This comprehensive PhD training programme will allow the translation of science into guidelines for healthy eating and the production of nutritionally improved food crops, leading to innovative food products, particularly for prevention and treatment of chronic diseases where age is a major risk factor. In this article, we summarise the programme and showcase the experiences of the first cohort of students as they start their substantive PhD projects after a year of research rotations.

Bioactive polysaccharides and oligosaccharides from garlic (Allium sativum L.): Production, physicochemical and biological properties, and structure-function relationships

Garlic is a common food, and many of its biological functions are attributed to its components including functional carbohydrates. Garlic polysaccharides and oligosaccharides as main components are understudied but have future value due to the growing demand for bioactive polysaccharides/oligosaccharides from natural sources. Garlic polysaccharides have molecular weights of 1 × 10³ to 2 × 10⁶  Da, containing small amounts of pectins and fructooligosaccharides and large amounts of inulin-type fructans ((2→1)-linked β-d-Fruf backbones alone or with attached (2→6)-linked β-d-Fruf branched chains). This article provides a detailed review of research progress and identifies knowledge gaps in extraction, production, composition, molecular characteristics, structural features, physicochemical properties, bioactivities, and structure-function relationships of garlic polysaccharides/oligosaccharides. Whether the extraction processes, synthesis approaches, and modification methods established for other non-garlic polysaccharides are also effective for garlic polysaccharides/oligosaccharides (to preserve their desired molecular structures and bioactivities) requires verification. The metabolic processes of ingested garlic polysaccharides/oligosaccharides (as food ingredients/dietary supplements), their modes of action in healthy humans or populations with chronic conditions, and molecular/chain organization-bioactivity relationships remain unclear. Future research directions related to garlic polysaccharides/oligosaccharides are discussed.

Glucose oxidase converted into a general sugar-oxidase

Entrapment of glucose oxidase (GOx) within metallic gold converts this widely used enzyme into a general saccharide oxidase. The following sugar molecules were oxidized by the entrapped enzyme (in addition to D-glucose): fructose, xylose, L-glucose, glucose-6-phosphate, sucrose, lactose, methylglucoside, and the tri-saccharide raffinose. With the exception of raffinose, none of these sugars have a natural specific oxidase. The origin of this generalization of activity is attributed to the strong protein-gold 3D interactions and to the strong interactions of the co-entrapped CTAB with both the gold, and the protein. It is proposed that these interactions induce conformational changes in the channel leading to the active site, which is located at the interface between the two units of the dimeric GOx protein. The observations are compatible with affecting the specific conformation change of pulling apart and opening this gate-keeper, rendering the active site accessible to a variety of substrates. The entrapment methodology was also found to increase the thermal stability of GOx up to 100 °C and to allow its convenient reuse, two features of practical importance.

Novel Insights Into the Phylogeny and Biotechnological Potential of Weissella Species

In this study, the genomes of the Weissella (W.) beninensis, W. diestrammenae, W. fabalis, W. fabaria, W. ghanensis, and W. uvarum type strains were sequenced and analyzed. Moreover, the ability of these strains to metabolize 95 carbohydrates was investigated, and the genetic determinants of such capability were searched within the sequenced genomes. 16S rRNA gene and genome-based-phylogeny of all the Weissella species described to date allowed a reassessment of the Weissella genus species groups. As a result, six distinct species groups within the genus, namely, W. beninensis, W. kandleri, W. confusa, W. halotolerans, W. oryzae, and W. paramesenteroides species groups, could be described. Phenotypic analyses provided further knowledge about the ability of the W. beninensis, W. ghanensis, W. fabaria, W. fabalis, W. uvarum, and W. diestrammenae type strains to metabolize certain carbohydrates and confirmed the interspecific diversity of the analyzed strains. Moreover, in many cases, the carbohydrate metabolism pathway and phylogenomic species group clustering overlapped. The novel insights provided in our study significantly improved the knowledge about the Weissella genus and allowed us to identify features that define the role of the analyzed type strains in fermentative processes and their biotechnological potential.

Incomplete degradation products of galactomannan from Sesbania cannabina modulated the cecal microbial community of laying hens

Galactomannan and its degradation products have been gaining attention based on their possible means for improving the natural defense of the host through modulation of the bacterial population in the gut. Herein, incomplete degradation products of galactomannan (IDPG) was supplemented into the diet of aged laying hens to investigate the efficacy of IDPG on the gut microbiome. Four treatments with six replicates of twelve 68-wk-old laying hens (Hy-Line variety brown) each were fed a basal diet supplemented with 0%, 0.01%, 0.025%, and 0.05% IDPG for 8 wk. Results showed that the propionate concentration significantly increased in laying hens fed a diet supplemented with 0.025% or 0.05% IDPG relative to the control diet (P < 0.05). Moreover, the results of 16S rRNA gene sequencing revealed that there was a notable elevation of microbiome species diversity due to the addition of IDPG, with a noted enrichment to phyla Bacteroidetes at the expense of Firmicutes and Proteobacteria. Metabolic prediction of the cecal microbiome suggested significant improvements to carbohydrate and lipid metabolism and a significant depletion for energy metabolism and infectious diseases. More importantly, a strong positive correlation between levels of genera Bacteroides, Rikenellaceae_RC9_gut_group, and Prevotellaceae_UCG-001 with high production of propionate was found using multivariate analysis. Our study demonstrated that IDPG acted by mainly enriching the phyla Bacteroidetes in the cecum, increasing species diversity, and cecal propionate concentrations. It seems that IDPG can be used as feed additives in laying hen farming due to its capacity to positively modulate the cecal microbiome and aid improve overall health.

Enterocin: Promising Biopreservative Produced by Enterococcus sp

Food preservation is a method used to handle and treat food products to slow down food spoilage and subsequently reduce the risk of foodborne illness. Nowadays, the demand for natural preservatives over chemical preservatives in food is increasing due to the awareness of consuming healthy food products without the risk of harmful side effects. Thus, the research and development of preservation techniques, referred to as biopreservation, is growing rapidly. In biopreservation methods, microorganisms that are known as lactic acid bacteria (LAB) and their antimicrobial substances are used to extend shelf life and maintain the nutritional value of foods. Among the most studied LAB are from the genus Enterococcus, which produces a bacteriocin called enterocin. Bacteriocins are ribosomal-synthesized antimicrobial peptides that are capable of inhibiting the growth of pathogenic bacteria that cause spoilage in food. LAB is generally regarded as safe (GRAS) for human consumption. The current application of LAB, notably Enterococcus sp. in the biopreservation of meat and meat-based products was highlighted in this review. This report also includes information on the effects of enzymes, temperature, and pH on the stability of bacteriocin produced by Enterococcus sp. An extensive compilation of numerous industry procedures for preserving meat has also been emphasized, highlighting the benefits and drawbacks of each method.

Effect of Hybrid Type and Harvesting Season on Phytochemistry and Antibacterial Activity of Extracted Metabolites from Salix Bark

Hundreds of different fast-growing Salix hybrids have been developed mainly for energy crops. In this paper, we studied water extracts from the bark of 15 willow hybrids and species as potential antimicrobial additives. Treatment of ground bark in water under mild conditions extracted 12-25% of the dry material. Preparative high-performance liquid chromatography is proven here as a fast and highly efficient tool in the small-scale recovery of raffinose from Salix bark crude extracts for structural elucidation. Less than half of the dissolved material was assigned by chromatographic (gas chromatography and liquid chromatography) and spectroscopic (mass spectrometry and nuclear magnetic resonance spectroscopy) techniques for low-molecular-weight compounds, including mono- and oligosaccharides (sucrose, raffinose, and stachyose) and aromatic phytochemicals (triandrin, catechin, salicin, and picein). The composition of the extracts varied greatly depending on the hybrid or species and the harvesting season. This information generated new scientific knowledge on the variation in the content and composition of the extracts between Salix hybrids and harvesting season depending on the desired molecule. The extracts showed high antibacterial activity on Staphylococcus aureus with a minimal inhibitory concentration (MIC) of 0.6-0.8 mg/mL; however, no inhibition was observed against Escherichia coli, Enterococcus faecalis, and Salmonella typhimurium. MIC of triandrin (i.e., 1.25 mg/mL) is reported for the first time. Although antibacterial triandrin and (+)-catechin were present in extracts, clear correlation between the antibacterial effect and the chemical composition was not established, which indicates that antibacterial activity of the extracts mainly originates from some not yet elucidated substances. Aquatic toxicity and mutagenicity assessments showed the safe usage of Salix water extracts as possible antibacterial additives.

Raffinose Family Oligosaccharides: Friend or Foe for Human and Plant Health?

Raffinose family oligosaccharides (RFOs) are widespread across the plant kingdom, and their concentrations are related to the environment, genotype, and harvest time. RFOs are known to carry out many functions in plants and humans. In this paper, we provide a comprehensive review of RFOs, including their beneficial and anti-nutritional properties. RFOs are considered anti-nutritional factors since they cause flatulence in humans and animals. Flatulence is the single most important factor that deters consumption and utilization of legumes in human and animal diets. In plants, RFOs have been reported to impart tolerance to heat, drought, cold, salinity, and disease resistance besides regulating seed germination, vigor, and longevity. In humans, RFOs have beneficial effects in the large intestine and have shown prebiotic potential by promoting the growth of beneficial bacteria reducing pathogens and putrefactive bacteria present in the colon. In addition to their prebiotic potential, RFOs have many other biological functions in humans and animals, such as anti-allergic, anti-obesity, anti-diabetic, prevention of non-alcoholic fatty liver disease, and cryoprotection. The wide-ranging applications of RFOs make them useful in food, feed, cosmetics, health, pharmaceuticals, and plant stress tolerance; therefore, we review the composition and diversity of RFOs, describe the metabolism and genetics of RFOs, evaluate their role in plant and human health, with a primary focus in grain legumes.

Efficacy and Safety of Probiotics for the Treatment of Alzheimer's Disease, Mild Cognitive Impairment, and Parkinson's Disease: A Systematic Review and Meta-Analysis

Background

Alzheimer's disease (AD) and Parkinson's disease (PD) are two of the most common neurodegenerative diseases, and mild cognitive impairment (MCI) is considered a prodromal stage of clinical AD. Animal studies have shown that probiotics can improve cognitive function and mitigate inflammatory response, however, results from randomized controlled trials in humans are still unclear.

Objectives

A systematic review and meta-analysis was conducted to evaluate the efficacy and safety of probiotic therapy on cognitive function, oxidative stress, and gastrointestinal function in patients with AD, MCI, and PD.

Methods

We searched the electronic databases such as PubMed, EMBASE, Cochrane Library until October 2020 for the eligible randomized controlled trials, as well as the unpublished and ongoing trials. Our primary endpoints were cognitive function, inflammatory and oxidative stress biomarkers, gastrointestinal function, and adverse events.

Results

After screening 2,459 titles and abstracts about AD or MCI, we selected 6 eligible studies (n = 499 patients). After screening 1,923 titles and abstracts about PD, we selected 5 eligible studies (n = 342 patients). Compared with the control group, treatment with probiotics improved the cognitive function of patients with AD in the intervention group (P = 0.023). Cognitive function also improved in MCI patients (P = 0.000). Inflammation-related indicators: Malondialdehyde (MDA) was significantly reduced (P = 0.000); and hs-CRP decreased (P = 0.003). Lipid-related indicators: VLDL decreased (P = 0.026); triglyceride decreased (P = 0.009); and insulin resistance level improved: decreased Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (P = 0.019).

Conclusion

Our analyses suggest that probiotics can improve cognitive and gastrointestinal symptoms in patients with AD, MCI, and PD, which is possibly through reducing inflammatory response and improving lipid metabolism. The safety has also been proven. However, more RCTs with rigorous study design are needed to support our findings.

Systematic Review Registration

PROSPERO, Identifier: CRD42021231502.

Bifidobacterium animalis subsp. lactis HN019 Effects on Gut Health: A Review

Optimal gut motility is central to bowel function and gut health. The link between the gut dysmotility related disorders and dysfunctional-intestinal barriers has led to a hypothesis that certain probiotics could help in normalizing gut motility and maintain gut health. This review investigates the roles of Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019™) on gut health, and its mechanisms of action in various pre-clinical and clinical studies. Research supports the hypothesis that B. lactis HN019™ has a beneficial role in maintaining intestinal barrier function during gastrointestinal infections by competing and excluding potential pathogens via different mechanisms; maintaining normal tight junction function in vitro; and regulating host immune defense toward pathogens in both in vitro and human studies. This has been observed to lead to reduced incidence of diarrhea. Interestingly, B. lactis HN019™ also supports normal physiological function in immunosenescent elderly and competes and excludes potential pathogens. Furthermore, B. lactis HN019™ reduced intestinal transit time and increased bowel movement frequency in functional constipation, potentially by modulating gut–brain–microbiota axis, mainly via serotonin signaling pathway, through short chain fatty acids derived from microbial fermentation. B. lactis HN019™ is thus a probiotic that can contribute to relieving gut dysmotility related disorders.

Culture media based on effluent derived from soy protein concentrate production for Lacticaseibacillus paracasei 90 biomass production: statistical optimisation, mineral characterization, and metabolic activities

The waste and by-products of the soybean industry could be an economic source of nutrients to satisfy the high nutritional demands for the cultivation of lactic acid bacteria. The aims of this work were to maximize the biomass production of Lacticaseibacillus paracasei 90 (L90) in three culture media formulated from an effluent derived from soy protein concentrate production and to assess the effects these media have on the enzymatic activity of L90, together with their influence on its fermentation profile in milk. The presence of essential minerals and fermentable carbohydrates (sucrose, raffinose, and stachyose) in the effluent was verified. L90 reached high levels of microbiological counts (∼ 9 log cfu mL^-1) and dry weight (> 1 g L^-1) on the three optimized media. Enzymatic activities (lactate dehydrogenase and β-galactosidase) of L90, and its metabolism of lactose and citric acid, as well as lactic acid and pyruvic acid production in milk, were modified depending on the growth media. The ability of the L90 to produce the key flavour compounds (diacetyl and acetoin) was maintained or improved by growing in the optimized media in comparison with MRS.

Identification of an Invertase With High Specific Activity for Raffinose Hydrolysis and Its Application in Soymilk Treatment

The hydrolyzation of raffinose into melibiose by using invertases under mild conditions improves the nutritional value of soybean products. However, this strategy has received little attention because a suitable invertase remains lacking. In this study, a novel invertase named InvDz13 was screened and purified from Microbacterium trichothecenolyticum and characterized. InvDz13 was one of the invertases with the highest specific activity toward raffinose. Specifically, it had a specific activity of 229 U/mg toward raffinose at pH 6.5 and 35°C. InvDz13 retained more than 80% of its maximum activity at pH 5.5–7.5 and 25–40°C and was resistant to or stimulated by most cations that presented in soymilk. In soymilk treated with InvDz13 under mild conditions, melibiose concentration increased from 3.1 ± 0.2 to 6.1 ± 0.1 mM due to raffinose hydrolyzation by InvDz13. Furthermore, the prebiotic property of InvDz13-treated soymilk was investigated via in vitro fermentation by human gut microbiota. Results showed that InvDz13 treatment increased the proportion of the beneficial bacteria Bifidobacterium and Lactobacillus by 1.6- and 3.7-fold, respectively. By contrast, the populations of Escherichia and Collinsella decreased by 1.8- and 11.7-fold, respectively. Thus, our results proved that the enzymatic hydrolysis of raffinose in soymilk with InvDz13 was practicable and might be an alternative approach to improving the nutritional value of soymilk.

Novel and emerging prebiotics: Advances and opportunities

Consumers are conscientiously changing their eating preferences toward healthier options, such as functional foods enriched with pre- and probiotics. Prebiotics are attractive bioactive compounds with multidimensional beneficial action on both human and animal health, namely on the gastrointestinal tract, cardiometabolism, bones or mental health. Conventionally, prebiotics are non-digestible carbohydrates which generally present favorable organoleptic properties, temperature and acidic stability, and are considered interesting food ingredients. However, according to the current definition of prebiotics, application categories other than food are accepted, as well as non-carbohydrate substrates and bioactivity at extra-intestinal sites. Regulatory issues are considered a major concern for prebiotics since a clear understanding and application of these compounds among the consumers, regulators, scientists, suppliers or manufacturers, health-care providers and standards or recommendation-setting organizations are of utmost importance. Prebiotics can be divided in several categories according to their development and regulatory status. Inulin, galactooligosaccharides, fructooligosaccharides and lactulose are generally classified as well established prebiotics. Xylooligosaccharides, isomaltooligosaccharides, chitooligosaccharides and lactosucrose are classified as "emerging" prebiotics, while raffinose, neoagaro-oligosaccharides and epilactose are "under development." Other substances, such as human milk oligosaccharides, polyphenols, polyunsaturated fatty acids, proteins, protein hydrolysates and peptides are considered "new candidates." This chapter will encompass actual information about the non-established prebiotics, mainly their physicochemical properties, market, legislation, biological activity and possible applications. Generally, there is a lack of clear demonstrations about the effective health benefits associated with all the non-established prebiotics. Overcoming this limitation will undoubtedly increase the demand for these compounds and their market size will follow the consumer's trend.

Dietary fibers as beneficial microbiota modulators: A proposed classification by prebiotic categories

Dietary fiber is a group of heterogeneous substances that are neither digested nor absorbed in the small intestine. Some fibers can be classified as prebiotics if they are metabolized by beneficial bacteria present in the hindgut microbiota. The aim of this review was to specify the prebiotic properties of different subgroups of dietary fibers (resistant oligosaccharides, non-starch polysaccharides, resistant starches, and associated substances) to classify them by prebiotic categories. Currently, only resistant oligosaccharides (fructans [fructooligosaccharides, oligofructose, and inulin] and galactans) are well documented as prebiotics in the literature. Other fibers are considered candidates to prebiotics or have prebiotic potential, and apparently some have no prebiotic effect on humans. This dietary fiber classification by the prebiotic categories contributes to a better understanding of these concepts in the literature, to the stimulation of the processing and consumption of foods rich in fiber and other products with prebiotic properties, and to the development of protocols and guidelines on food sources of prebiotics.

Modulation of the immune response and metabolism in germ-free rats colonized by the probiotic Lactobacillus salivarius LI01

The gut microbiota plays an important role in multifaceted physiological functions in the host. Previous studies have assessed the probiotic effects of Lactobacillus salivarius LI01. In this study, we aimed to investigate the potential effects and putative mechanism of L. salivarius LI01 in immune modulation and metabolic regulation through the monocolonization of germ-free (GF) Sprague-Dawley (SD) rats with L. salivarius LI01. The GF rats were separated into two groups and administered a gavage of L. salivarius LI01 or an equal amount of phosphate-buffered saline. The levels of serum biomarkers, such as interleukin (IL)-1α, IL-5, and IL-10, were restored by L. salivarius LI01, which indicated the activation of Th0 cell differentiation toward immune homeostasis. L. salivarius LI01 also stimulated the immune response and metabolic process by altering transcriptional expression in the ileum and liver. A Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed significant enrichment of the 5'-adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, which indicated that L. salivarius LI01 exerts an effect on energy accumulation. The LI01 group showed alterations in fecal carbohydrates accompanied by an increased body weight gain. In addition, L. salivarius LI01 produced indole-3-lactic acid (ILA) and enhanced arginine metabolism by rebalancing the interconversion between arginine and proline. These findings provide evidence showing that L. salivarius LI01 can directly impact the host by modulating immunity and metabolism. KEY POINTS : • Lactobacillus salivarius LI01 conventionalizes the cytokine profile and activates the immune response. • LI01 modulates carbohydrate metabolism and arginine transaction. • LI01 generates tryptophan-derived indole-3-lactic acid. • The cytochrome P450 family contributes to the response to altered metabolites.

A Phylogenetic View on the Role of Glycerol for Growth Enhancement and Reuterin Formation in Limosilactobacillus reuteri

Lineages within the species Limosilactobacillus reuteri have specialized to various hosts and their genomes reflect these adaptations. The pdu-cbi-cob-hem gene cluster is conserved in most human and poultry isolates but is infrequent in rodent and porcine isolates. This gene cluster confers the transformation of glycerol into 3-hydroxy-propionaldehyde (reuterin), which can either be secreted and function as precursor of the antimicrobial compound acrolein or serve as an electron acceptor that enhances the organisms’ growth rate. However, it remains unclear which of these two functions is more relevant for L. reuteri evolution and ecology. Here we characterized the effect of glycerol on growth rate and reuterin formation in L. reuteri strains across different phylogenetic lineages during growth on ecologically relevant carbohydrates. We further evaluated the innate reuterin resistance among these strains to infer a possible role of reuterin in the evolution of strains. Results revealed that the poultry/human lineage VI strain, L. reuteri DSM 17938 shows more growth enhancement through glycerol and greater capacity for reuterin production on glucose and maltose as compared to human lineage II strains. Interestingly, reuterin production in lineage II strains was significantly elevated on raffinose and lactose, reaching levels similar to DSM 17938. On all carbohydrates tested, reuterin production occurred during the exponential growth phase and became undetectable during the stationary growth phase. The amount of reuterin produced was sufficient to inhibit E. coli, suggesting that it could be ecologically relevant, but the resistance towards reuterin among L. reuteri strains was highly variable and, for the most part, unrelated to the strain’s capacity for reuterin production. Overall, the findings suggest differences in the substrate-specific regulation of the pdu cluster in L. reuteri lineages that might be reflective of their ecological niches, e.g., chicken foregut versus human infant and adult large intestine. Such information can inform future studies on the ecology of L. reuteri and guide the development of synbiotic applications to improve the therapeutic use of this species.

α-Galactosidase and Sucrose-Kinase Relationships in a Bi-functional AgaSK Enzyme Produced by the Human Gut Symbiont Ruminococcus gnavus E1

Plant α-galactosides belonging to the raffinose family oligosaccharides (RFOs) and considered as prebiotics, are commonly degraded by α-galactosidases produced by the human gut microbiome. In this environment, the Ruminococcus gnavus E1 symbiont-well-known for various benefit-is able to produce an original RgAgaSK bifunctional enzyme. This enzyme contains an hydrolytic α-galactosidase domain linked to an ATP dependent extra-domain, specifically involved in the α-galactoside hydrolysis and the phosphorylation of the glucose, respectively. However, the multi-modular relationships between both catalytic domains remained hitherto unexplored and has been, consequently, herein investigated. Biochemical characterization of heterologously expressed enzymes either in full-form or in separated domains revealed similar kinetic parameters. These results were supported by molecular modeling studies performed on the whole enzyme in complex with different RFOs. Further enzymatic analysis associated with kinetic degradation of various substrates followed by high pressure anionic exchange chromatography revealed that catalytic efficiency decreased as the number of D-galactosyl moieties branched onto the oligosaccharide increased, suggesting a preference of RgAgaSK for RFO's short chains. A wide prevalence and abundance study on a human metagenomic library showed a high prevalence of the RgAgaSK encoding gene whatever the health status of the individuals. Finally, phylogeny and synteny studies suggested a limited spread by horizontal transfer of the clusters' containing RgAgaSK to only few species of Firmicutes, highlighting the importance of these undispersed tandem activities in the human gut microbiome.

Effects of regular and decaffeinated roasted coffee (Coffea arabica and Coffea canephora) extracts and bioactive compounds on in vitro probiotic bacterial growth

The aim of this study was to investigate the effects of coffee species, roast degree and decaffeination on in vitro probiotic bacterial growth, and to identify the major coffee compounds responsible for such effects. Six C. arabica and C. canephora extracts (regular medium and dark roasted and decaffeinated medium roasted), and five bioactive compounds (chlorogenic acid, galactomannan, type 2 arabinogalactan, caffeine and trigonelline) were individually incorporated into a modified low-carbon broth medium-(mMRS), at different concentrations (0.5 to 1.5% soluble coffee and 0.05 to 0.8 mg mL-1 standard solutions). Inulin and fructooligosaccharides (FOS) were used as prebiotic references. MRS and mMRS were used as rich and poor medium controls, respectively. The growth of Lactobacillus rhamnosus GG ATCC 53103-(GG), L. acidophilus LA-5-(LA), Bifidobacterium animalis DN-173010-(BA) and B. animalis subsp. lactis BB12-(BB12), as well as the growth inhibition of non-probiotic Escherichia coli ATCC 25922 were evaluated. Differences in growth between mMRS and treatments (Δlog CFU mL-1) were compared by ANOVA and Tukey's test, and considered when p ≤ 0.05. Overall, after 48 h incubation, the medium roasted arabica coffee extract increased the growth of GG, LA and BA (range: Δlog CFU mL-1 = 0.5 to 1.8), while the dark roasted arabica coffee extract increased BB12 growth (range: Δlog CFU mL-1 = 0.9 to 1.7), in a dose dependent manner. Improved performances of GG, LA and BA were promoted by higher polysaccharides and CGA concentrations, with better performance for Lactobacillus sp. The tested coffee bioactive compounds promoted the poor growth of BB12. Plain caffeine did not promote Bifidobacterium sp. growth and limited the growth of Lactobacillus sp. Regular C. arabica and C. canephora extracts inhibited the growth of E. coli, while the decaffeinated extracts promoted its growth. The present results show that coffee consumption can selectively improve the growth of probiotic strains, thus exerting a prebiotic effect, and show that coffee roasting and decaffeination affect this property and that different strains utilize different coffee components to grow.

Pengembangan Soyghurt (Yoghurt Susu Kacang Kedelai) Sebagai Minuman Probiotik Tinggi Isoflavon

 ABSTRACTBackground: Increased prevalence of non-communicable diseases in Indonesia occurs as the result of dietary transition, which is traditional dietary habit into fast-food dietary habit. Thus, triggers the formation of free radicals in human body which can be prevented by consumption of high antioxidant food. Soyghurt or soymilk yoghurt was a probiotic drink made of fermented soybean as an alternative drink with high antioxidant to prevent non-communicable diseases. Soybean was a major source of isoflavone as antioxidant and the bioavailability of isoflavone can be increased by fermentation in soyghurt.Objectives: To developed high isoflavone soyghurt or soymilk yoghurt as probiotic drink.Methods: This study used experimental method by used completely randomized design with added ratio of soybean were 0%, 15%, 20%, 25%. Soyghurt was analyzed by chemical properties (proximate analysis and free isoflavone content), physical properties (viscosity and pH), also total lactic acid bacteria. Formula selection based on exponential comparison method.Results: The selected formula of soyghurt was the third formula which added by 25% ratio of soybean with water content (81,74%), ash content (0,49%), protein content (5,98%), fat content (11,61%), carbohydrate content (0,35%), genistein content (250,46 μg/g), daidzein content (173,02 μg/g), viscosity (7111,4 cPoice), pH (4,63), and total LAB (3,7 x 107 coloni/ml).Conclusions: Soyghurt had compatible total lactic acid bacteria with total starter bacteria in indonesian national standards of yoghurt and fulfilled claim of high isoflavone based on calculation of nutritional label reference.ABSTRAKLatar Belakang: Peningkatan prevalensi penyakit tidak menular di Indonesia terjadi sebagai akibat adanya transisi pola konsumsi pangan, yaitu pola konsumsi pangan lokal menjadi pola konsumsi pangan cepat saji. Hal tersebut memicu terbentuknya radikal bebas di dalam tubuh yang dapat dicegah dengan mengonsumsi makanan atau kudapan tinggi antioksidan. Soyghurt atau yoghurt susu kacang kedelai merupakan minuman probiotik berbahan dasar susu nabati yang difermentasi dan diperuntukkan sebagai alternatif minuman tinggi antioksidan untuk mencegah terjadinya penyakit tidak menular. Jenis antioksidan utama dalam kacang kedelai adalah isoflavon yang bioavailabilitasnya akan meningkat selama proses fermentasi soyghurt. Tujuan: Melakukan pengembangan produk soyghurt atau yoghurt susu kacang kedelai sebagai minuman probiotik tinggi isoflavon.Metode: Jenis penelitian eksperimental dengan desain penelitian Rancangan Acak Lengkap menggunakan satu perlakuan yaitu penambahan rasio kacang kedelai sebesar 0%, 15%, 20%, 25%. Kemudian dilakukan analisis sifat kimia (uji proksimat dan kadar isoflavon bebas), sifat fisik (viskositas dan nilai pH), serta uji total bakteri asam laktat. Penentuan formula soyghurt terpilih dilakukan dengan metode perbandingan eksponensial.Hasil: Formula soyghurt terpilih adalah soyghurt formula ketiga dengan rasio penambahan kacang kedelai sebesar 25% dengan kadar air (81,74%), kadar abu (0,49%), kadar protein (5,98%), kadar lemak (11,61%), kadar karbohidrat (0,35%), kadar genistein (250,46 μg/g), kadar daidzein (173,02 μg/g), viskositas (7111,4 cPoice), tingkat derajat keasaman (4,63), dan total BAL (3,7 x 107 koloni/ml).Kesimpulan: Soyghurt memiliki total bakteri asam laktat yang sesuai dengan standar nasional indonesia dan telah memenuhi klaim tinggi isoflavon berdasarkan acuan label gizi.

Changes in Intestinal Microbiota and Predicted Metabolic Pathways During Colonic Fermentation of Mango (Mangifera indica L.)-Based Bar Indigestible Fraction

Mango (Mangifera indica L.) peel and pulp are a source of dietary fiber (DF) and phenolic compounds (PCs) that constituent part of the indigestible fraction (IF). This fraction reaches the colon and acts as a carbon and energy source for intestinal microbiota. The effect of mango IF on intestinal microbiota during colonic fermentation is unknown. In this study, the isolated IF of a novel 'Ataulfo' mango-based bar (snack) UV-C irradiated and non-irradiated (UVMangoB and MangoB) were fermented. Colonic fermentation occurred in vitro under chemical-enzymatic, semi-anaerobic, batch culture and controlled pH colonic conditions. Changes in the structure of fecal microbiota were analyzed by 16s rRNA gene Illumina MiSeq sequencing. The community´s functional capabilities were determined in silico. The MangoB and UVMangoB increased the presence of Faecalibacterium, Roseburia, Eubacterium, Fusicatenibacter, Holdemanella, Catenibacterium, Phascolarctobacterium, Buttiauxella, Bifidobacterium, Collinsella, Prevotella and Bacteroides genera. The alpha indexes showed a decrease in microbial diversity after 6 h of colonic fermentation. The coordinates analysis indicated any differences between irradiated and non-irradiated bar. The metabolic prediction demonstrated that MangoB and UVMangoB increase the microbiota carbohydrate metabolism pathway. This study suggests that IF of mango-based bar induced beneficial changes on microbial ecology and metabolic pathway that could be promissory to prevention or treatment of metabolic dysbiosis. However, in vivo interventions are necessary to confirm the interactions between microbiota modulating and intestinal beneficial effects.

A silver-substituted phosphomolybdate prevents the growth of bacteria without affecting the balance of reactive oxygen species

A novel 2D nanoscale silver-substituted Strandberg-type phosphomolybdate shows good inhibitory effect on the growth of Escherichia coli.

UV-C pretreatment of fresh-cut faba beans (Vicia faba) for shelf life extension: Effects of domestic microwaving for consumption

Faba beans have a short shelf life which is even reduced after fresh-cut processing mainly due to browning and dehydration. In that sense, the effects of a UV-C treatment (3 kJ m^-2), compared with non-exposed beans (CTRL), were studied on the sensory and microbial quality, and bioactive and anti-nutritional content of fresh-cut faba beans (cv. Muchamiel) during storage at 5 ℃. The effect of a domestic microwaving (3 min, 900 W) on bioactive and anti-nutritional compounds of fresh seeds prior to consumption at each sampling time was also studied. UV-C treatment extended the fresh-cut faba bean shelf life from 7 to 10 days with browning score (the main sensory parameter adversely affected) of 8 and 1 log unit lower than CTRL at day 10. UV-C did not negatively affect the total antioxidant capacity of samples during storage. The phytic acid and raffinose contents decreased by 30/40%, respectively, after 10 days, without influence of the UV-C treatment. Microwaving reduced the phytic acid and condensed tannins contents by 30% in those samples stored for up to six days, with low microwaving effect in the last storage days. Nevertheless, UV-C improved the condensed tannins reductions through storage (≈30%) compared with non-irradiated samples.

Enhanced mucosal immune responses, immune related genes and growth performance in common carp (Cyprinus carpio) juveniles fed dietary Pediococcus acidilactici MA18/5M and raffinose

The present study was conducted to evaluate the effects of dietary Pediococcus acidilactici (PA) and raffinose (RF) alone or in combination on growth performance, mucosal immune factors and immune related genes expression in common carp (Cyprinus carpio) juveniles. Fish with initial weight of 10.0 ± 2.5 g were fed the following experimental diets for 60 days: control (without supplementation), prebiotic (2 g RF kg^-1 diet), probiotic (6 × 10⁸ CFU g^-1PA) and synbiotic (2 g RF kg^-1+ 6 × 10⁸ CFU g^-1PA). Carp fed synbiotic and probiotic diets had the highest (19.53 ± 0.16) and the lowest (18.05 ± 0.65) final body weight, respectively and the other experimental groups showed intermediate values. Singular administration of PA or in combination with 2 g RF kg^-1 significantly increased skin mucus total immunoglobulin (Ig) and protein compared other groups, meanwhile, values of skin mucus protease activity enhanced by dietary immunostimulants administration in comparison with the control (P < 0.05). The expression of gene encoding lysozyme in skin pronouncedly increased by supplementing diets with singular or mixture of PA and RF; however, the expression of intestinal lysozyme gene as well as tumor necrosis factor-α genes expression in skin and intestine were not affected by administrating different immunostimulants (P > 0.05). The highest growth performance was noticed in fish fed synbiotic (P < 0.05). Overall, the combination of 2 g RF kg^-1 with 6 × 10⁸ CFU g^-1PA is recommended for improving immunological responses of C. carpio juveniles.

In vitro fermentation of raffinose by the human gut bacteria

Raffinose has become a major focus of research interest and recent studies have shown that besides beneficial bifidobacteria and lactobacilli, Escherichia coli, Enterococcus faecium and Streptococcus pneumoniae can also utilize raffinose and raffinose might lead to flatulence in some hosts. Therefore, it is required to find out the raffinose-metabolizing bacteria in the gut and the bacteria responsible for the flatulence. The BLASTP search results showed that the homologous proteins of glycosidases related to raffinose utilization are widely distributed in 196 of the 528 gut bacterial strains. Fifty-nine bacterial strains belonging to nine species of five genera were isolated from human feces and were found to be capable of utilizing raffinose; of these species, Enterococcus avium and Streptococcus salivarius were reported for the first time. High-performance liquid chromatography (HPLC) analysis of the supernatants of the nine species revealed that the bacteria could utilize raffinose in different manners. Glucose and melibiose were detected in the supernatants of Enterococcus avium E5 and Streptococcus salivarius B5, respectively. However, no resulting saccharides of raffinose degradation were detected in the supernatants of other seven strains, indicating that they had different raffinose utilization types from Enterococcus avium E5 and Streptococcus salivarius B5. Gas was produced with raffinose utilization by Escherichia coli, Enterococcus faecium, Streptococcus macedonicus, Streptococcus pasteurianus and Enterococcus avium. Thus, more attention should be paid to the raffinose-utilizing bacteria besides bifidobacteria and further studies are required to reveal the mechanisms of raffinose utilization to clarify the relationship between raffinose and gut bacteria.

Preventive Effects of Different Fermentation Times of Shuidouchi on Diphenoxylate-Induced Constipation in Mice

This study compares the prevention effects of Shuidouchi with different fermentation times on constipation in mice. Shuidouchi is a short-time fermented soybean product. By improving its processing technology, it can incur better biological activity and become a health food. The Shuidouchi-treated mice were evaluated using constipation-related kits, quantitative polymerase chain reaction (qPCR), and Western blot assays. After the mice were fed 72-h-fermented Shuidouchi (72-SDC) for 9 d, the defecation time to excrete the first black stool was lower than that of the control and 24-SDC and 48-SDC groups, but was much higher than that of the normal group. The gastrointestinal (GI) transit of the small intestine of the 72-SDC group was higher than that of the control and the 24-SDC and 48-SDC groups, but lower that of the normal group. Meanwhile, 72-SDC could significantly increase the levels of ghrelin, endothelin-1 (ET-1), vasoactive intestinal peptide (VIP), and acetylcholinesterase (AchE) in the serum of constipated mice compared to the levels in mice in the control group. Moreover, 72-SDC could raise c-Kit, stem cell factor (SCF), glial cell-derived neurotrophic factor (GNDF), neuronal nitric oxide synthase (nNOS), and endothelial nitric oxide synthase (eNOS) messenger RNA (mRNA) and protein expression levels, and reduce transient receptor potential cation channel subfamily V member 1 (TRPV1) and inducible nitric oxide synthase (iNOS) expression levels in small-intestinal tissue compared to the levels in the control group. Meanwhile, 72-SDC also raised ghrelin mRNA expression in gastric tissue and transient receptor potential ankyrin 1 (TRPA1) mRNA expression in colon tissue compared to the control group mice; these effects were stronger than those of 24-SDC and 48-SDC. Shuidouchi has good preventative effects on constipation and performs best when fermented for at least 72 h.

A binuclear copper-substituted phosphomolybdate with reactive oxygen species catalytic ability and antimicrobial activity

A magnetic binuclear Cu-substituted Strandberg POM can produce ROS and inhibit the growth of E. coli.

Trends in the Use of Plant Non-Starch Polysaccharides within Food, Dietary Supplements, and Pharmaceuticals: Beneficial Effects on Regulation and Wellbeing of the Intestinal Tract

As the demand for healthy products targeted to prevent or ameliorate bowel disease and digestive disorders of the intestinal tract is increasing, this review describes non-starch polysaccharides, such as β-glucan, arabinoxylan, galactomannan, fructan, and heteropolysaccarides from mucilages, as useful sources for adequate and tailor-made products aimed for regulation of the colon and wellbeing effects on the gut microbiota. Their monosaccharide composition, structure, molecular dimensions, physicochemical characteristics and growth stimulation of lactobacilli and bifidobacteria in the gut microbiota is reported. Arabinoxylan from wheat and rye grains is discussed as an ingredient for gluten and lectin-free bread and baked goods. Galactomannans from legumes and their partially hydrolysed products are presented as sources for specific healthy products against bowel disease and digestive discomfort. Commercial fructan products obtained from inulin, fructan of agave, and fructooligosaccharides are discussed in detail as a selective substrate for fermentation by health-promoting bacteria in the colon, such as lactobacilli and bifidobacteria. Structurally different heteropolysaccharides from mucilages of traditional medicinal plants, such as seeds from psyllium, flax, chan, chia, and basil or cladodes from Opuntia spp., are discussed as useful sources of dietary fibre, with prebiotic characteristics and digestive regulation in the intestinal tract as well.

Influence of Probiotics Administration on Gut Microbiota Core: A Review on the Effects on Appetite Control, Glucose, and Lipid Metabolism

An increasing number of studies has shown that dietary probiotics exert beneficial health effects in both humans and animals. It is well established that gut microbiota play a pivotal role in regulating host metabolism, and a growing number of studies has elucidated that probiotics positively interfere with gut microbiota. Accumulating evidence shows that probiotics, through their metabolic activity, produce metabolites that in turn contribute to positively affect host physiology. For these reasons, probiotics have shown significant potential as a therapeutic tool for a diversity of diseases, but the mechanisms through which probiotics act has not been fully elucidated yet. The goal of this review was to provide evidence on the effects of probiotics on gut microbiota changes associated with host metabolic variations, specifically focusing on feed intake and lipid and glucose metabolism. In addition, we review probiotic interaction with the gut microbiota. The information collected here will give further insight into the effects of probiotics on the gut microbiota and their action on metabolite release, energy metabolism, and appetite. This information will help to improve knowledge to find better probiotic therapeutic strategies for obesity and eating disorders.