scholarly journals Human gut microbiota – its diversity and impact on our health

2021 ◽  
pp. 71-100
Author(s):  
Sebastian Wardak
Keyword(s):  
Gut Microbiota ◽  
Short Chain Fatty Acids ◽  
Living Environment ◽  
Socioeconomic Conditions ◽  
Human Gut ◽  
Modern Molecular Biology ◽  
Rapid Changes ◽  
Human Digestive Tract ◽  
The Impact ◽  
Generation Sequencing

The human digestive tract is the living environment for billions of cells of various microorganisms that are part of the human microflora. The use of modern molecular biology techniques, such as NGS (Next Generation Sequencing), made it possible to study the microorganisms inhabiting the intestines and to understand their impact on human health. The gut microbiota plays a significant role in the synthesis and metabolism of many nutrients and metabolites, including short-chain fatty acids (SCFA), amino acids, lipids, bile acids and vitamins. Many factors such as diet, age, climate, and socioeconomic conditions influence the diversity of the microbiota. Rapid changes in the composition of the microbiota (disturbance of homeostasis) can lead to dysbiosis - a condition associated not only with intestinal disorders, but also with numerous extraintestinal diseases. The present work is a review of current reports on: research techniques used to analyze microbiota, the impact of various factors on its diversity and the impact of microbiota on our health.

scholarly journals Enrichment of Food With Tannin Extracts Promotes Healthy Changes in the Human Gut Microbiota

2021 ◽  
Vol 12 ◽  
Author(s):  
Silvia Molino ◽  
Alberto Lerma-Aguilera ◽  
Nuria Jiménez-Hernández ◽  
María José Gosalbes ◽  
José Ángel Rufián-Henares ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Short Chain Fatty Acids ◽  
Human Gut ◽  
Human Gut Microbiota ◽  
Wood Extracts ◽  
Potential Benefits ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing ◽  
Booster Effect

Food and food bioactive components are major drivers of modulation of the human gut microbiota. Tannin extracts consist of a mix of bioactive compounds, which are already exploited in the food industry for their chemical and sensorial properties. The aim of our study was to explore the viability of associations between tannin wood extracts of different origin and food as gut microbiota modulators. 16S rRNA amplicon next-generation sequencing (NGS) was used to test the effects on the gut microbiota of tannin extracts from quebracho, chestnut, and tara associated with commercial food products with different composition in macronutrients. The different tannin-enriched and non-enriched foods were submitted to in vitro digestion and fermentation by the gut microbiota of healthy subjects. The profile of the short chain fatty acids (SCFAs) produced by the microbiota was also investigated. The presence of tannin extracts in food promoted an increase of the relative abundance of the genus Akkermansia, recognized as a marker of a healthy gut, and of various members of the Lachnospiraceae and Ruminococcaceae families, involved in SCFA production. The enrichment of foods with tannin extracts had a booster effect on the production of SCFAs, without altering the profile given by the foods alone. These preliminary results suggest a positive modulation of the gut microbiota with potential benefits for human health through the enrichment of foods with tannin extracts.

scholarly journals The Impact of a Dynamic Working Environment on Human Gut Microbiota

2021 ◽  
Author(s):  
Lu Ling ◽  
Jun Zhou ◽  
Qianlong Meng ◽  
Ziran Zhang ◽  
Wenkun Li ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Clinical Characteristics ◽  
Dietary Habits ◽  
Living Environment ◽  
Working Environment ◽  
Rrna Gene ◽  
Human Gut ◽  
Human Gut Microbiota ◽  
Train Drivers ◽  
The Impact

Gut microbiota dysbiosis is associated with a variety of diseases, such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), metabolic diseases, allergic diseases, neurodevelopmental disorders and cancer. The human gut microbiota can be influenced by a variety of factors, including geography, dietary habits, living environment, age and altered lifestyle etc. This study was conducted to explore the gut microbiota compositions in officials who are in a stable working environment and train drivers who are in a dynamic working environment. Microbiota communities in the feces of 80 officials and 88 train drivers were analyzed using Illumina MiSeq sequencing targeting the V3-V4 region of 16S ribosomal RNA (rRNA) gene and ITS1 region of fungi. There were significant differences between the two groups in diversity and richness of gut microbiota, while the microbial community compositions of the two groups were similar. The relationship between gut microbiota and clinical characteristics was investigated. We found that more bacteria and fungi were positively correlated with clinical characteristics. Functional prediction analysis of the gut microbiota between the two groups by PICRUSt2 revealed significant differences between the official group and the train driver group. Elucidating these differences of the microbiome between the two groups will provide a foundation understanding of the impact of a dynamic environment on gut microbiota.

scholarly journals The Influence of Diet and Sex on the Gut Microbiota of Lean and Obese JCR:LA-cp Rats

2021 ◽  
Vol 9 (5) ◽  
pp. 1037
Author(s):  
Craig Resch ◽  
Mihir Parikh ◽  
J. Alejandro Austria ◽  
Spencer D. Proctor ◽  
Thomas Netticadan ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Control Diet ◽  
Bacterial Species ◽  
Alpha Diversity ◽  
Short Chain Fatty Acids ◽  
Female Rats ◽  
Dependent Manner ◽  
Male And Female ◽  
Ground Flaxseed ◽  
The Impact

There is an increased interest in the gut microbiota as it relates to health and obesity. The impact of diet and sex on the gut microbiota in conjunction with obesity also demands extensive systemic investigation. Thus, the influence of sex, diet, and flaxseed supplementation on the gut microbiota was examined in the JCR:LA-cp rat model of genetic obesity. Male and female obese rats were randomized into four groups (n = 8) to receive, for 12 weeks, either (a) control diet (Con), (b) control diet supplemented with 10% ground flaxseed (CFlax), (c) a high-fat, high sucrose (HFHS) diet, or (d) HFHS supplemented with 10% ground flaxseed (HFlax). Male and female JCR:LA-cp lean rats served as genetic controls and received similar dietary interventions. Illumine MiSeq sequencing revealed a richer microbiota in rats fed control diets rather than HFHS diets. Obese female rats had lower alpha-diversity than lean female; however, both sexes of obese and lean JCR rats differed significantly in β-diversity, as their gut microbiota was composed of different abundances of bacterial types. The feeding of an HFHS diet affected the diversity by increasing the phylum Bacteroidetes and reducing bacterial species from phylum Firmicutes. Fecal short-chain fatty acids such as acetate, propionate, and butyrate-producing bacterial species were correspondingly impacted by the HFHS diet. Flax supplementation improved the gut microbiota by decreasing the abundance of Blautia and Eubacterium dolichum. Collectively, our data show that an HFHS diet results in gut microbiota dysbiosis in a sex-dependent manner. Flaxseed supplementation to the diet had a significant impact on gut microbiota diversity under both flax control and HFHS dietary conditions.

scholarly journals Microbiota-Associated Metabolites and Related Immunoregulation in Colorectal Cancer

Cancers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 4054
Author(s):  
Yan Chen ◽  
Ying-Xuan Chen
Keyword(s):  
Colorectal Cancer ◽  
Fatty Acids ◽  
Gut Microbiota ◽  
Immune Responses ◽  
Short Chain Fatty Acids ◽  
Short Chain ◽  
Indole Derivatives ◽  
Human Gut ◽  
Growing Body ◽  
Specific Influence

A growing body of research has found close links between the human gut microbiota and colorectal cancer (CRC), associated with the direct actions of specific bacteria and the activities of microbiota-derived metabolites, which are implicated in complex immune responses, thus influencing carcinogenesis. Diet has a significant impact on the structure of the microbiota and also undergoes microbial metabolism. Some metabolites, such as short-chain fatty acids (SCFAs) and indole derivatives, act as protectors against cancer by regulating immune responses, while others may promote cancer. However, the specific influence of these metabolites on the host is conditional. We reviewed the recent insights on the relationships among diet, microbiota-derived metabolites, and CRC, focusing on their intricate immunomodulatory responses, which might influence the progression of colorectal cancer.

scholarly journals Effects of Rich in Β-Glucans Edible Mushrooms on Aging Gut Microbiota Characteristics: An In Vitro Study

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2806 ◽  
Author(s):  
Evdokia K. Mitsou ◽  
Georgia Saxami ◽  
Emmanuela Stamoulou ◽  
Evangelia Kerezoudi ◽  
Eirini Terzi ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Wheat Straw ◽  
In Vitro Study ◽  
Short Chain Fatty Acids ◽  
Edible Mushrooms ◽  
Elderly Subjects ◽  
Microbiota Composition ◽  
The Impact ◽  
Gut Microbiota Composition

Alterations of gut microbiota are evident during the aging process. Prebiotics may restore the gut microbial balance, with β-glucans emerging as prebiotic candidates. This study aimed to investigate the impact of edible mushrooms rich in β-glucans on the gut microbiota composition and metabolites by using in vitro static batch culture fermentations and fecal inocula from elderly donors (n = 8). Pleurotus ostreatus, P. eryngii, Hericium erinaceus and Cyclocybe cylindracea mushrooms derived from various substrates were examined. Gut microbiota composition (quantitative PCR (qPCR)) and short-chain fatty acids (SCFAs; gas chromatography (GC)) were determined during the 24-h fermentation. P. eryngii induced a strong lactogenic effect, while P. ostreatus and C. cylindracea induced a significant bifidogenic effect (p for all <0.05). Furthermore, P. eryngii produced on wheat straw and the prebiotic inulin had comparable Prebiotic Indexes, while P. eryngii produced on wheat straw/grape marc significantly increased the levels of tested butyrate producers. P. ostreatus, P. eryngii and C. cylindracea had similar trends in SCFA profile; H. erinaceus mushrooms were more diverse, especially in the production of propionate, butyrate and branched SCFAs. In conclusion, mushrooms rich in β-glucans may exert beneficial in vitro effects in gut microbiota and/or SCFAs production in elderly subjects.

scholarly journals Considerations for the design and conduct of human gut microbiota intervention studies relating to foods

2020 ◽  
Vol 59 (8) ◽  
pp. 3347-3368
Author(s):  
J. R. Swann ◽  
M. Rajilic-Stojanovic ◽  
A. Salonen ◽  
O. Sakwinska ◽  
C. Gill ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Intestinal Microbiota ◽  
Intervention Studies ◽  
Health Claims ◽  
Host Responses ◽  
Human Gut ◽  
Eligibility Criteria ◽  
Functional Changes ◽  
Human Gut Microbiota ◽  
The Impact

AbstractWith the growing appreciation for the influence of the intestinal microbiota on human health, there is increasing motivation to design and refine interventions to promote favorable shifts in the microbiota and their interactions with the host. Technological advances have improved our understanding and ability to measure this indigenous population and the impact of such interventions. However, the rapid growth and evolution of the field, as well as the diversity of methods used, parameters measured and populations studied, make it difficult to interpret the significance of the findings and translate their outcomes to the wider population. This can prevent comparisons across studies and hinder the drawing of appropriate conclusions. This review outlines considerations to facilitate the design, implementation and interpretation of human gut microbiota intervention studies relating to foods based upon our current understanding of the intestinal microbiota, its functionality and interactions with the human host. This includes parameters associated with study design, eligibility criteria, statistical considerations, characterization of products and the measurement of compliance. Methodologies and markers to assess compositional and functional changes in the microbiota, following interventions are discussed in addition to approaches to assess changes in microbiota–host interactions and host responses. Last, EU legislative aspects in relation to foods and health claims are presented. While it is appreciated that the field of gastrointestinal microbiology is rapidly evolving, such guidance will assist in the design and interpretation of human gut microbiota interventional studies relating to foods.

scholarly journals In Vitro Fecal Fermentation Patterns of Arabinoxylan from Rice Bran on Gut Microbiota in Normal Weight and Overweight/Obese Subjects

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1560-1560
Author(s):  
Inah Gu ◽  
Wing Shun Lam ◽  
Daya Marasini ◽  
Cindi Brownmiller ◽  
Brett Savary ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Rice Bran ◽  
Block Design ◽  
16S Rrna Gene Sequencing ◽  
Short Chain Fatty Acids ◽  
Normal Weight ◽  
Rrna Gene ◽  
Gut Health ◽  
The Impact

Abstract Objectives Arabinoxylan is a non-starch polysaccharide and rich in wheat, rice and many other cereal grains. Diets high in fiber help promoting gut health in obesity. The objective of this study was to investigate the impact of arabinoxylan from rice bran on the gut microbiota and short chain fatty acids (SCFA) in normal weight (NW) and overweight/obese (OO) subjects through in vitro fecal fermentation. Methods Arabinoxylan was extracted from rice bran fiber. For in vitro fecal fermentation, each fecal sample from NW (n = 6, 3 males and 3 females) and OO (n = 7, 3 males and 4 females) was diluted into anaerobic medium with three treatments: control (no substrates), fructooligosaccharides (FOS, a well-known prebiotic), and arabinoxylan. Samples were incubated at 37˚C and aliquots were taken at 0, 4, 8, 12 and 24 h. SCFA content from samples at all timepoints was analyzed using HPLC. Samples at 0 and 24 h were used for gut microbiota analysis through 16S rRNA gene sequencing. Statistical analyses were performed for the randomized complete block design, where the weight classes are confounded with blocks (subjects). Friedman test was used to determine the difference at 5% level of significance. Results As a result, arabinoxylan treatment significantly increased total SCFA concentration in both NW and OO subjects than control (P &lt; 0.05), comparable to FOS treatment. Between weight classes under arabinoxylan treatment, OO group showed a significantly higher total SCFA content than NW group (P &lt; 0.05). Arabinoxylan changed gut microbial population at the genus level, stimulating Bifidobacterium, Collinsella and Blautia and decreasing Clostridium XIVa and b, Dorea and Oscillibacter (P &lt; 0.05). In addition, different microbiome population was shown in weight classes with three treatments, showing higher Bacteroides in NW and higher Prevotella in OO. Conclusions These results showed that arabinoxylan from rice bran modified gut microbiota in both weight classes, increasing total SCFA content. This study suggests that arabinoxylan from rice bran may have a potential impact on microbial gut health in obesity with prebiotic activities. Funding Sources University of Arkansas.

scholarly journals Gut Microbiome Modulation Based on Probiotic Application for Anti-Obesity: A Review on Efficacy and Validation

2019 ◽  
Vol 7 (10) ◽  
pp. 456 ◽  
Author(s):  
Kaliyan Barathikannan ◽  
Ramachandran Chelliah ◽  
Momna Rubab ◽  
Eric Banan-Mwine Daliri ◽  
Fazle Elahi ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Gut Microbiome ◽  
Molecular Mechanisms ◽  
Short Chain Fatty Acids ◽  
Genetic Profile ◽  
Fecal Transplantation ◽  
Intestinal Microbes ◽  
Prevalence Of Obesity ◽  
Future Direction ◽  
The Impact

The growing prevalence of obesity has become an important problem worldwide as obesity has several health risks. Notably, factors such as excessive food consumption, a sedentary way of life, high sugar consumption, a fat-rich diet, and a certain genetic profile may lead to obesity. The present review brings together recent advances regarding the significance of interventions involving intestinal gut bacteria and host metabolic phenotypes. We assess important biological molecular mechanisms underlying the impact of gut microbiota on hosts including bile salt metabolism, short-chain fatty acids, and metabolic endotoxemia. Some previous studies have shown a link between microbiota and obesity, and associated disease reports have been documented. Thus, this review focuses on obesity and gut microbiota interactions and further develops the mechanism of the gut microbiome approach related to human obesity. Specifically, we highlight several alternative diet treatments including dietary changes and supplementation with probiotics. The future direction or comparative significance of fecal transplantation, synbiotics, and metabolomics as an approach to the modulation of intestinal microbes is also discussed.

scholarly journals Dietary Fatty Acids Sustain the Growth of the Human Gut Microbiota

2018 ◽  
Vol 84 (21) ◽  
Author(s):  
Richard Agans ◽  
Alex Gordon ◽  
Denise Lynette Kramer ◽  
Sergio Perez-Burillo ◽  
José A. Rufián-Henares ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Small Intestine ◽  
Fatty Acid ◽  
Gut Microbiota ◽  
Short Chain Fatty Acids ◽  
Dietary Fatty Acids ◽  
Dietary Fats ◽  
High Fat ◽  
Human Gut ◽  
Content Type

ABSTRACTWhile a substantial amount of dietary fats escape absorption in the human small intestine and reach the colon, the ability of resident microbiota to utilize these dietary fats for growth has not been investigated in detail. In this study, we used anin vitromultivessel simulator system of the human colon to reveal that the human gut microbiota is able to utilize typically consumed dietary fatty acids to sustain growth. Gut microbiota adapted quickly to a macronutrient switch from a balanced Western diet-type medium to its variant lacking carbohydrates and proteins. We defined specific genera that increased in their abundances on the fats-only medium, includingAlistipes,Bilophila, and several genera of the classGammaproteobacteria. In contrast, the abundances of well-known glycan and protein degraders, includingBacteroides,Clostridium, andRoseburiaspp., were reduced under such conditions. The predicted prevalences of microbial genes coding for fatty acid degradation enzymes and anaerobic respiratory reductases were significantly increased in the fats-only environment, whereas the abundance of glycan degradation genes was diminished. These changes also resulted in lower microbial production of short-chain fatty acids and antioxidants. Our findings provide justification for the previously observed alterations in gut microbiota observed in human and animal studies of high-fat diets.IMPORTANCEIncreased intake of fats in many developed countries has raised awareness of potentially harmful and beneficial effects of high fat consumption on human health. Some dietary fats escape digestion in the small intestine and reach the colon where they can be metabolized by gut microbiota. We show that human gut microbes are able to maintain a complex community when supplied with dietary fatty acids as the only nutrient and carbon sources. Such fatty acid-based growth leads to lower production of short-chain fatty acids and antioxidants by community members, which potentially have negative health consequences on the host.

scholarly journals Prebiotics and Community Composition Influence Gas Production of the Human Gut Microbiota

mBio ◽  
2020 ◽  
Vol 11 (5) ◽  
Author(s):  
Xiaoqian Yu ◽  
Thomas Gurry ◽  
Le Thanh Tu Nguyen ◽  
Hunter S. Richardson ◽  
Eric J. Alm
Keyword(s):  
Fatty Acids ◽  
Chemical Composition ◽  
Gut Microbiota ◽  
Community Composition ◽  
Human Body ◽  
Ex Vivo ◽  
Short Chain Fatty Acids ◽  
Gas Production ◽  
Human Gut ◽  
Human Gut Microbiota

ABSTRACT Prebiotics confer benefits to human health, often by promoting the growth of gut bacteria that produce metabolites valuable to the human body, such as short-chain fatty acids (SCFAs). While prebiotic selection has strongly focused on maximizing the production of SCFAs, less attention has been paid to gases, a by-product of SCFA production that also has physiological effects on the human body. Here, we investigate how the content and volume of gas production by human gut microbiota are affected by the chemical composition of the prebiotic and the community composition of the microbiota. We first constructed a linear system model based on mass and electron balance and compared the theoretical product ranges of two prebiotics, inulin and pectin. Modeling shows that pectin is more restricted in product space, with less potential for H2 but more potential for CO2 production. An ex vivo experimental system showed pectin degradation produced significantly less H2 than inulin, but CO2 production fell outside the theoretical product range, suggesting fermentation of fecal debris. Microbial community composition also impacted results: methane production was dependent on the presence of Methanobacteria, while interindividual differences in H2 production during inulin degradation were driven by a Lachnospiraceae taxon. Overall, these results suggest that both the chemistry of the prebiotic and the composition of the microbiota are relevant to gas production. Metabolic processes that are relatively prevalent in the microbiome, such as H2 production, will depend more on substrate, while rare metabolisms such as methanogenesis depend more strongly on microbiome composition. IMPORTANCE Prebiotic fermentation in the gut often leads to the coproduction of short-chain fatty acids (SCFAs) and gases. While excess gas production can be a potential problem for those with functional gut disorders, gas production is rarely considered during prebiotic design. In this study, we combined the use of theoretical models and an ex vivo experimental platform to illustrate that both the chemical composition of the prebiotic and the community composition of the human gut microbiota can affect the volume and content of gas production during prebiotic fermentation. Specifically, more prevalent metabolic processes such as hydrogen production were strongly affected by the oxidation state of the probiotic, while rare metabolisms such as methane production were less affected by the chemical nature of the substrate and entirely dependent on the presence of Methanobacteria in the microbiota.

Sign in / Sign up

Export Citation Format

Share Document