Study on fecal fermentation characteristics of aloe polysaccharides in vitro and their predictive modeling

Dynamic variations in physicochemical characteristics of oolong tea polysaccharides during simulated digestion and fecal fermentation in vitro

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Wuyi rock tea polysaccharides (WYP) were slightly degraded after in vitro digestion.

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The indigestible WYP could be degraded and utilized during the fecal fermentation.

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Dynamic variations in physicochemical profiles of WYP were revealed.

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Beneficial bacteria, such as Lactococcus and Bifidobacterium, increased.

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Acetic, propionic, and n-butyric acids increased during fecal fermentation.

In this study, dynamic variations in physicochemical characteristics of polysaccharides from ‘Wuyi rock’ tea (WYP) at different simulated digestion and fecal fermentation stages in vitro were studied. Results revealed that physicochemical characteristics of WYP were slightly altered after the simulated digestion in vitro, and its digestibility was about 8.38%. Conversely, physicochemical characteristics of the indigestible WYP, including reducing sugar, chemical composition, constituent monosaccharide, molecular weight, and FT-IR spectrum, were obviously altered after the fecal fermentation in vitro, and its fermentability was about 42.18%. Notably, the indigestible WYP could remarkably modulate the microbial composition via promoting the proliferation of profitable intestinal microbes, such as Bacteroides, Lactococcus, and Bifidobacterium. Moreover, it could also enhance the generation of short-chain fatty acids. The results showed that WYP was slightly digested in the gastrointestinal tract in vitro, but could be obviously utilized by intestinal microbiota, and might possess the potential to improve intestinal health.

Involvement of the Intestinal Microbiota in the Appearance of Multiple Sclerosis: Aloe vera and Citrus bergamia as Potential Candidates for Intestinal Health

Multiple sclerosis (MS) is a neurological and inflammatory autoimmune disease of the Central Nervous System in which selective activation of T and B lymphocytes prompts a reaction against myelin, inducing demyelination and axonal loss. Although MS is recognized to be an autoimmune pathology, the specific causes are many; thus, to date, it has been considered a disorder resulting from environmental factors in genetically susceptible individuals. Among the environmental factors hypothetically involved in MS, nutrition seems to be well related, although the role of nutritional factors is still unclear. The gut of mammals is home to a bacterial community of about 2000 species known as the “microbiota”, whose composition changes throughout the life of each individual. There are five bacterial phylas that make up the microbiota in healthy adults: Firmicutes (79.4%), Bacteroidetes (16.9%), Actinobacteria (2.5%), Proteobacteria (1%) and Verrucomicrobia (0.1%). The diversity and abundance of microbial populations justifies a condition known as eubiosis. On the contrary, the state of dysbiosis refers to altered diversity and abundance of the microbiota. Many studies carried out in the last few years have demonstrated that there is a relationship between the intestinal microflora and the progression of multiple sclerosis. This correlation was also demonstrated by the discovery that patients with MS, treated with specific prebiotics and probiotics, have greatly increased bacterial diversity in the intestinal microbiota, which might be otherwise reduced or absent. In particular, natural extracts of Aloe vera and bergamot fruits, rich in polyphenols and with a high percentage of polysaccharides (mostly found in indigestible and fermentable fibers), appear to be potential candidates to re-equilibrate the gut microbiota in MS patients. The present review article aims to assess the pathophysiological mechanisms that reveal the role of the microbiota in the development of MS. In addition, the potential for supplementing patients undergoing early stages of MS with Aloe vera as well as bergamot fibers, on top of conventional drug treatments, is discussed.

Comfrey polysaccharides modulate the gut microbiota and its metabolites SCFAs and affect the production performance of laying hens

Effects of dietary supplementation of comfrey polysaccharides (CPs) on production performance, egg quality, and microbial composition of cecum in laying hens were evaluated. A total of 240 laying hens were allocated into 4 groups with 6 replicates per group. The laying hens were fed diets containing CPs at levels of 0, 0.5, 1.0, and 1.5 %, respectively. The results showed that the egg production rate increased by 5.97 %, the egg mass improved by 6.71 %, and the feed conversion rate reduced by 5.43 % in the 1.0 % supplementation group of CPs compared with those in the control group. The digestibility of ash, crude fat, and phosphorus was notably improved by the addition of CPs at 1.0 % (P < 0.05). The relative abundances of Bacteroidetes at the phylum level, Bacteroidaceae, Rikenellaceae, and Prevotellaceae at the family level were increased by CPs (P < 0.05). The relative abundances of Bacteroides, Megamonas, Rikenellaceae_RC9_gut_group, [Ruminococcus]_torques_group, Methanobrevibacter, Desulfovibrio, Romboutsia, Alistipes, and Intestinimonas at the genus level were increased by CPs (P < 0.05). Dietary supplementation of CPs could enhance the production performance of laying hens, which might be related to the improvement of nutrient digestibility and microbial community modulations in the cecum. Therefore, CPs have potential application value as prebiotics in laying hens.

Ameliorative effects of chlorogenic acid on alcoholic liver injury in mice via gut microbiota informatics

Chlorogenic acid (CGA) is a functional phenolic acid widely used in food and medicine-related fields. It has been proved to be effective in the treatment of alcoholic liver disease (ALD). However, the exact mechanism by which CGA prevents ALD, especially from the crosstalk between gut and liver, has not been previously reported. This work was aimed to explore the protective effects of CGA against ALD and its relationships to gut-liver axis abnormalities. Experimental results showed the increased (p < 0.05) serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), low density lipoprotein (LDL), total cholesterol (TC) and triglyceride (TG) levels of mice fed with ethanol were ameliorated by supplementing with CGA. Moreover, CGA promoted the production of n-butyric acid by nearly 3 times (1.78 vs 0.62 nM, p < 0.01), a short-chain fatty acid that helps maintain the integrity of the intestinal barrier. Furthermore, CGA alleviated microbial dysbiosis, evidenced by the increased relative abundances of beneficial bacteria Muribaculaceae, Bacteroides, Alloprevotella, and Parabacteroides, and decreased that of opportunistic pathogens Eubacterium_nodatum, Eubacterium_ruminantium, and Anaerotruncus. Correlation analysis further elucidated the microbiota altered after CGA intervention was positively correlated with short-chain fatty acids and antioxidant indexes, while negatively correlated with inflammatory cytokines. In summary, these findings suggested the hepatoprotective effect of CGA was ascribed to the modulation of gut-liver axis homeostasis.

In-depth investigation of the mechanisms of Echinacea purpurea polysaccharide mitigating alcoholic liver injury in mice via gut microbiota informatics and liver metabolomics

Accumulating evidence suggests that the pathogenesis of alcoholic liver disease (ALD) is strongly correlated with abnormalities of the gut-liver axis. Echinacea purpurea polysaccharide (EPP) is a homogeneous polysaccharide, which has been shown to mitigate ALD. However, the effects of EPP on gut microbiome and consequently on hepatic metabolism have yet to be explored. In this study, the microbiome and metabolomics were combined to explore the effects of EPP on gut microbiota and hepatic metabolism, and the relationship between both was further revealed by Spearman correlation analysis. Results exhibited EPP reversed alcohol-induced disturbances in gut microbiota, evidenced by increased abundance of Muribaculaceae, Lactobacillus, and Bacteroides and decreased abundance of Escherichia_Shigella and Enterococcus. Besides, EPP promoted the production of n-butyric acid, a short-chain fatty acid that maintains the integrity of the intestinal barrier. Moreover, EPP improved alterations in hepatic metabolites, and characteristic metabolites such as Berberine and Ponasterone as well as key metabolic pathways, particularly Nitrogen metabolism, were identified. Furthermore, correlation analysis suggested significant associations between gut microbes and hepatic metabolites, which in turn confirmed EPP alleviated ALD via the gut-liver axis. Therefore, these findings elucidated in-depth mechanisms of EPP against ALD and provided a new target for intervention in alcohol-related diseases.

Disordered Gut Microbiota in Colorectal Tumor-Bearing Mice Altered Serum Metabolome Related to Fufangchangtai

Purpose: This study aimed to investigate the relationship between gut microbiota (GM) and serum metabolism using antineoplastic Fufangchangtai (FFCT) as the model prescription in the treatment of colorectal cancer (CRC).

Methods: Tumor-bearing mice and normal mice were administered different doses of FFCT. The tumor volume of tumor-bearing mice was observed. The levels of CD4+ and CD8+ T cells in the blood, spleen, and tumor of mice were determined using a flow cytometer. The bacterial microbiota in stool samples from mice and the serum metabolomics of FFCT-treated mice and fecal microbiota transplantation mice were detected using 16s RNA sequencing and liquid chromatography–mass spectrometry (LC/MS), respectively.

Results: The tumor volume of mice showed no significant decrease after FFCT intervention. The levels of CD4+ and CD8+T lymphocytes showed a significant increase under the intervention of FFCT. GM of colorectal tumor-bearing mice and healthy mice were determined, and the diversity and abundance of Firmicutes, Deferribacteres, Bacteroidetes, and Proteobacteria were significantly different between the two groups. Furthermore, we found that the levels of matrine, isogingerenone B, and armillaripin were significantly decreased in tumor-bearing mice after FFCT intervention, indicating that the tumor-induced dysbiosis of gut bacteria may affect the absorption and metabolism of FFCT. Under the intervention of FFCT, serum metabolism of mice transplanted with feces from CRC patients showed less metabolites related to FFCT than that from healthy people, indicating that GM could be a single factor affecting the metabolism of FFCT. Furthermore, we found that different doses of FFCT-treated mice had higher abundance of Roseburia, Turicibacter, and Flexispira than that in the non-intervention control group. Firmicutes and Bacteroidetes in FFCT-treated groups showed a similar trend compared to the healthy group, indicating that FFCT might correct the intestinal microenvironment by modulating gut microbiota in colorectal tumor-bearing mice.

Conclusion: The dysbiosis of GM in tumor-bearing mice reduced the serum metabolites related to FFCT, and FFCT could correct the disordered GM of colorectal tumor-bearing mice to exert efficacy.

Astilbin from Smilax glabra Roxb. alleviates high-fat diet-induced metabolic dysfunction

Overweight, obesity, and related diseases are currently the major public health problems worldwide. Astilbin, extracted from the rhizome of Smilax glabra Roxb., is known to have significant anti-inflammatory activity and hepatoprotective effect. Studies have shown that it can inhibit adipogenesis in adipocytes in vitro; however, the intervention benefits of astilbin against obesity and related diseases along with its associated mechanisms remain unknown. This study aimed to demonstrate the impact of astilbin consumption on the overall biochemical pattern of high-fat diet (HFD) mice by using a combined multi-omics approach. Our data indicated that astilbin reduced body weight, insulin resistance, and inflammation in mice fed an HFD. Astilbin improved HFD-induced gut microbial dysbiosis by decreasing the Firmicutes-to-Bacteroidetes ratio, by increasing beneficial bacteria such as Alistipes and Muribaculum and decreasing harmful bacteria including Lachnospiraceae FCS020 group, Coriobacteriaceae UCG-002, and Lachnospiraceae UCG-008, resulting in enhanced intestinal carbohydrate and lipid metabolism. Meanwhile, astilbin protected the integrity of the intestinal barrier in HFD mice, increased short-chain fatty acid levels, and reduced metabolic endotoxemia. We further showed that astilbin attenuated hepatic lipid droplet aggregation and triglyceride accumulation in HFD mice, affected glutamate metabolism-related pathways, and enhanced hepatic ATP transduction pathways and attenuated xanthine metabolism pathways in mice, which were positively correlated with the abundance of Alistipes and negatively correlated with Ruminococcaceae UCG-003. The results highlighted that astilbin could be used as a prebiotic for the prevention of "gut-liver axis" damage and metabolic disruption in obese individuals.

Diet composition affects long-term zearalenone exposure on the gut-blood-liver axis metabolic dysfunction in mice

Zearalenone (ZEN), one of the most contaminated Fusarium toxins worldwide, is very common in contaminating wheat, corn oil and other foods. People are more vulnerable to ZEN exposure with more daily caloric intake, yet little is known about the combined effect of different dietary patterns with mycotoxins. This study aimed to compare the effects of long-term ZEN exposure on the overall biochemical landscape of the "gut-blood-liver axis" under normal diet and high-fat diet (HFD) using a combined multi-omics approach. The results indicated that ZEN exposure, possibly via the phenylalanine metabolic pathway, led to dysbiosis of mouse flora, suppression of short-chain fatty acids (SCFAS) metabolism, systemic inflammatory responses, and disturbances in serum and liver metabolism, which were exacerbated in synergy with HFD and ultimately led to a more severe state of lipid metabolism in the liver. We further found that ZEN exposure attenuated the indole-3-propionic acid (IPA) metabolic pathway, enhanced 2-hydroxybutyric acid metabolism in serum, and attenuated β-alanine metabolism in liver which was positively correlated with the abundance of Prevotellaceae UCG-004, Prevotellaceae UCG-001, and Prevotellaceae NK3B31 groups. The results highlighted the damaging effects of ZEN on the gut-blood-liver axis under different dietary patterns, which might serve as a reference for future studies exploring the combined effects of fungal toxins and multiple dietary patterns.

Network Pharmacology Exploration Reveals Gut Microbiota Modulation as a Common Therapeutic Mechanism for Anti-Fatigue Effect Treated with Maca Compounds Prescription

Maca compounds prescription (MCP) is a common botanical used in dietary supplements, primarily to treat exercise-induced fatigue. The aim of this study is to elucidate the multi-target mechanism of MCP on fatigue management via network pharmacology and gut microbiota analysis. Databases and literature were used to screen the chemical compounds and targets of MCP. Subsequently, 120 active ingredients and 116 fatigue-related targets played a cooperative role in managing fatigue, where several intestine-specific targets indicated the anti-fatigue mechanism of MCP might be closely related to its prebiotics of intestinal bacteria. Thus, forced swimming tests (FSTs) were carried and mice fecal samples were collected and analyzed by 16S rRNA sequencing. Gut microbiota were beneficially regulated in the MCP-treated group in phylum, genus and OTU levels, respectively, and that with a critical correlation included Lactobacillus and Candidatus Planktophila. The results systematically reveal that MCP acts against fatigue on multi-targets with different ingredients and reshapes the gut microbial ecosystem.

Targeting Gut Microbiota With Natural Polysaccharides: Effective Interventions Against High-Fat Diet-Induced Metabolic Diseases

Unhealthy diet, in particular high-fat diet (HFD) intake, can cause the development of several metabolic disorders, including obesity, hyperlipidemia, type 2 diabetes mellitus (T2DM), non-alcoholic fatty liver disease (NAFLD), and metabolic syndrome (MetS). These popular metabolic diseases reduce the quality of life, and induce premature death worldwide. Evidence is accumulating that the gut microbiota is inextricably associated with HFD-induced metabolic disorders, and dietary intervention of gut microbiota is an effective therapeutic strategy for these metabolic dysfunctions. Polysaccharides are polymeric carbohydrate macromolecules and sources of fermentable dietary fiber that exhibit biological activities in the prevention and treatment of HFD-induced metabolic diseases. Of note, natural polysaccharides are among the most potent modulators of the gut microbiota composition. However, the prebiotics-like effects of polysaccharides in treating HFD-induced metabolic diseases remain elusive. In this review, we introduce the critical role of gut microbiota human health and HFD-induced metabolic disorders. Importantly, we review current knowledge about the role of natural polysaccharides in improving HFD-induced metabolic diseases by regulating gut microbiota.

Effect of polysaccharides from Tibetan turnip (Brassica rapa L.) on the gut microbiome in vitro fermentation and in vivo metabolism

Tibetan turnip ( Brassica rapa L. ) polysaccharide (TTP) is an active ingredient and has been studied for many years due to its biological effect. There are few studies on...

Combination of microbiome and metabolome to analyze the cross-cooperation mechanism of Echinacea purpurea polysaccharide with gut microbiota in vitro and in vivo

Echinacea purpurea polysaccharide (EPP) is a functional compound in Echinacea purpurea. At the present, it is generally recognized that plant polysaccharides can regulate the intestinal microecology, but there are few...

Chronic in vitro fermentation and in vivo metabolism: Extracellular polysaccharides from Sporidiobolus pararoseus regulate the intestinal microbiome of humans and mice

The fungus Sporidiobolus pararoseus not only produces carotenoids, but also produces bioactive extracellular polysaccharides (SPP). However, the relationship between SPP and the metabolism of gut microbiome is unclear. The aim of this study was to investigate the mechanism of SPP regulating intestinal health in vivo and in vitro. Results showed that SPP are nondigestible polysaccharides after the digestion with simulated stomach and small intestinal juice in vitro. After SPP was cultured in an in vitro intestinal simulation system for seven days, the concentration of short-chain fatty acids (SCFAs) increased; the microbial diversity changed; the relative abundance of Bifidobacterium and Streptococcus increased; and that of Escherichia Shigella and Lachnospiraceae NK4A136 decreased. In addition, metabolism of SPP by the mice colonic microbiome showed SPP decreased the relative abundance of Firmicutes and Bacteroidota, while the relative abundance of Verrucomicrobiota, Desulfobacterota, and Actinobacteriota increased. Finally, predicted Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolism results also showed that SPP can enhance the metabolism of cofactors, vitamins, amino acids, starch, and sucrose. In conclusion, SPP can multiply the intestinal beneficial bacteria of humans and mice, promote the production of SCFAs and metabolism of amino acids, and promote intestinal health.

Desulfovibrio vulgaris, a potent acetic acid-producing bacterium, attenuates nonalcoholic fatty liver disease in mice

The emerging evidence supports the use of prebiotics like herb-derived polysaccharides for treating nonalcoholic fatty liver disease (NAFLD) by modulating gut microbiome. The present study was initiated on the microbiota-dependent anti-NAFLD effect of Astragalus polysaccharides (APS) extracted from Astragalus mongholicus Bunge in high-fat diet (HFD)-fed mice. However, the exact mechanisms underlying the beneficial effects of APS on NAFLD formation remain poorly understood.Co-housing experiment was used to assess the microbiota dependent anti-NAFLD effect of APS. Then, targeted metabolomics and metagenomics were adopted for determining short-chain fatty acids (SCFAs) and bacteria that were specifically enriched by APS. Further in vitro experiment was carried out to test the capacity of SCFAs-producing of identified bacterium. Finally, the anti-NAFLD efficacy of identified bacterium was tested in HFD-fed mice.Our results first demonstrated the anti-NAFLD effect of APS in HFD-fed mice and the contribution of gut microbiota. Moreover, our results indicated that SCFAs, predominantly acetic acid were elevated in APS-supplemented mice and ex vivo experiment. Metagenomics revealed that D. vulgaris from Desulfovibrio genus was not only enriched by APS, but also a potent generator of acetic acid, which showed significant anti-NAFLD effects in HFD-fed mice. In addition, D. vulgaris modulated the hepatic gene expression pattern of lipids metabolism, particularly suppressed hepatic fatty acid synthase (FASN) and CD36 protein expression.Our results demonstrate that APS enriched D. vulgaris is effective on attenuating hepatic steatosis possibly through producing acetic acid, and modulation on hepatic lipids metabolism in mice. Further studies are warranted to explore the long-term impacts of D. vulgaris on host metabolism and the underlying mechanism.

Microbial succession of lignocellulose degrading bacteria during composting of corn stalk

The discarding and burning of corn stalks in the fields after harvesting lead to environmental pollution and waste of resources. Composting is an effective way to disposal of the crop straws. Composting is a complex biochemical process and need a detail studied in cold region. Hence, the succession process of bacteria and Actinomycetes in the process of corn stalk composting in cold region was studied by 16SrRNA. Alpha diversity analysis showed that the detection results could represent the real situation. The bacterial community diversity from high to low was F50 > F90 > F0 > F10 > F20. The results of beta analysis showed that F20 and F50 had the most similar microbial structure at the phylum level, and the difference between F0 and F20 was the largest. The dominant microbes changed from Proteobacteria and Bacteroidetes in F0 in heating stage to Firmicutes and Proteobacteria, Actinobacteria and Firmicutes in F10 during early high temperature stage, and Actinobacteria, Proteobacteria and Bacteroidetes in cooling and post composting phases. Actinobacteria and Firmicutes were the dominant bacteria in the whole composting process. In the composting process, the microbial community was mainly involved in amino acid metabolism related to nitrogen transformation and carbohydrate metabolism related to lignocellulose degradation. Lignin and hemicellulose were mainly degraded in thermophilic stage. The conversion of nitrogen and degradation of cellulose occurred mainly in the early stages of composting. The research will be helpful to understand the biochemical process of composting in cold region.

Polysaccharides confer benefits in immune regulation and multiple sclerosis by interacting with gut microbiota

Pharmacological and clinical studies have consistently demonstrated that polysaccharides exhibit great potential on immune regulation. Polysaccharides can interact directly or indirectly with the immune system, triggering cell-cell communication and molecular recognition, leading to immunostimulatory responses. Gut microbiota is adept at foraging polysaccharides as energy sources and confers benefits in the context of immunity and chronic autoimmune disease, such as multiple sclerosis. A compelling set of interconnectedness between the gut microbiota, natural polysaccharides, and immune regulation has emerged. In this review, we highlighted the available avenues supporting the existence of these interactions, with a focus on cytokines-mediated and SCFAs-mediated pathways. Additionally, the neuroimmune mechanisms for gut microbiota communication with the brain in multiple sclerosis are also discussed, which will lay the ground for ameliorate multiple sclerosis via polysaccharide intervention.

In-depth analysis of the mechanisms of aloe polysaccharides on mitigating subacute colitis in mice via microbiota informatics

Aloe polysaccharides (APs) are indigestible bioactive polysaccharides, while can be fermented by colonic microbiota. Although plant polysaccharides can alleviate subacute ulcerative colitis (SUC), the mechanisms APs regulated SUC via colonic microbiota have not been fully explored. Hence, to elucidate the complex interactions between the novel APs, colonic microbiota, SCFAs, and inflammation, the SUC mouse model and in-depth analysis were performed, including multiple bioinformatics analysis and structural equation modeling (SEM). After APs intervention, SCFAs and SCFAs-producing genus, including Akkermansia and Blautia, were increased in colon, and the colonic inflammation and barrier dysfunction were alleviated significantly in SUC mice. Spearman analysis found positive correlations between microbiota and SCFAs. PICRUSt2 and KEGG analysis revealed 6-pyruvoyltetra hydropterin synthase in folate biosynthesis metabolism pathway was activated, while phosphotransferase system was inhibited. SEM results further proved APs was beneficial to gut micro-ecological balance in mice via SCFAs metabolism and anti-inflammatory functions. Together, APs could be exploited to alleviate SUC as dietary therapeutics.

Aloe polysaccharides ameliorate acute colitis in mice via Nrf2/HO-1 signaling pathway and short-chain fatty acids metabolism

Aloe polysaccharides (APs) are acetyl polysaccharides. It has been reported APs could protect mice from ulcerative colitis (UC), but the complex interactions between APs and the intestinal barrier were unclear. Here, we investigated the relationship between APs and UC, and determined the synergistic effects of Nrf2/HO-1 signaling pathway and short-chain fatty acids (SCFAs) metabolism on protecting intestinal barrier in acute UC mice. Results showed APs could scavenge free radicals in vitro. In vivo, APs had the antioxidant and anti-inflammatory effect both in serum and colon. Besides, the pathological results showed APs could alleviate colonic lesions. Furthermore, our study indicated treatment with APs effectively increased SCFAs production. The inhibition of acute UC in mice was correlated with the APs-mediated effects on improving the expression of ZO-1, occludin, Nrf2, HO-I, and NQO1. Thus, APs effectively promoted the intestinal barrier via Nrf2/HO-1 signaling pathway and SCFAs metabolism, effectively ameliorating acute colitis in mice.