Deciphering the influence of physicochemical and microbial parameters of the human digestive tract on orally-ingested microplastics using in vitro gut models

Abstract Objectives Taro (Colocasia escuknta), a culturally important staple food of the native Hawaiian diet, is high in fiber content, reaching 4.1 g/100 g. Prebiotics are carbohydrates that are indigestible by the digestive tract, which can selectively stimulate probiotic growth and/or activities in the colon. Due to taro's high fiber content, it was hypothesized to have prebiotic potential. This study aimed to evaluate the effect of taro on the growth and adherence of probiotic Lactobacillus species in an in vitro human digestion system for the improvement of the human gut microbiome. Methods Four probiotic Lactobacillus species, including L. acidophilus, L. paracasei, L. rhamnosus, and L. plantarum, were individually paired with 2% (w/v) taro. In addition to taro, 2% (w/v) glucose and inulin were used as controls. The pairings were subjected to an in vitro human digestive tract simulation of the mouth, stomach, and intestinal conditions to assess the fate of tested probiotics. Furthermore, an auto-agglutination assay was conducted to evaluate the effect of taro on self-agglutination of the individual probiotics. Lastly, the Caco-2 cell line was used to determine whether taro could influence the ability of tested probiotics to adhere to human intestinal epithelial cells. Results Results indicated that L. acidophilus, L. paracasei, and L. plantarum experienced greater growth in the simulated intestinal tract when paired with taro than with inulin or glucose. In addition, L. paracasei showed strong self-agglutination ability and had the greatest adherence percentage to Caco-2 cells. Conclusions In conclusion, taro is a strain-specific potential prebiotic that can be utilized as a dietary aid to modulate a healthy gut microbiota. Funding Sources USDA-ARS. USDA-NIFA Hatch University of Hawai'i Mānoa MahiMicrobes Program

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Tripartite relationship between gut microbiota, intestinal mucus and dietary fibers: towards preventive strategies against enteric infections

FEMS Microbiology Reviews ◽

10.1093/femsre/fuaa052 ◽

2020 ◽

Author(s):

Sauvaitre Thomas ◽

Etienne-Mesmin Lucie ◽

Sivignon Adeline ◽

Mosoni Pascale ◽

Courtin Christophe ◽

...

Keyword(s):

Gut Microbiota ◽

Digestive Tract ◽

In Vitro Models ◽

Enteric Pathogens ◽

Dietary Fibers ◽

Human Gut ◽

Intestinal Mucus ◽

Enteric Infections ◽

Human Digestive Tract

Abstract The human gut is inhabited by a large variety of microorganims involved in many physiological processes and collectively refered as to gut microbiota. Disrupted microbiome has been associated with negative health outcomes and especially could promote the onset of enteric infections. To sustain their growth and persistence within the human digestive tract, gut microbes and enteric pathogens rely on two main polysaccharide compartments, namely dietary fibers and mucus carbohydrates. Several evidences suggest that the three-way relationship between gut microbiota, dietary fibers and mucus layer could unravel the capacity of enteric pathogens to colonize the human digestive tract and ultimately lead to infection. The review starts by shedding light on similarities and differences between dietary fibers and mucus carbohydrates structures and functions. Next, we provide an overview of the interactions of these two components with the third partner, namely the gut microbiota, under health and diseased situations. The review will then provide insights into the relevance of using dietary fibers interventions to prevent enteric infections with a focus on gut microbial imbalance and impaired-mucus integrity. Facing the numerous challenges in studying microbiota-pathogen-dietary fiber-mucus interactions, we lastly describe the characteristics and potentialities of currently available in vitro models of the human gut.

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The in Vitro Catabolism of Histamine in Tissues of the Digestive Tract in Sheep

Acta Veterinaria Scandinavica ◽

10.1186/bf03547839 ◽

1967 ◽

Vol 8 (2) ◽

pp. 136-149

Author(s):

Ø. V. Sjaastad

Keyword(s):

Digestive Tract

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Gluten-degrading bacteria: availability and applications

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11263-5 ◽

2021 ◽

Author(s):

Viia Kõiv ◽

Tanel Tenson

Keyword(s):

Microbial Communities ◽

Digestive Tract ◽

Storage Proteins ◽

Gluten Free Diet ◽

Natural Food ◽

Gluten Free ◽

Efficient Treatment ◽

Gluten Intolerance ◽

Degrading Bacteria ◽

Human Digestive Tract

Abstract Gluten is a mixture of storage proteins in wheat and occurs in smaller amounts in other cereal grains. It provides favorable structure to bakery products but unfortunately causes disease conditions with increasing prevalence. In the human gastrointestinal tract, gluten is cleaved into proline and gluten rich peptides that are not degraded further. These peptides trigger immune responses that might lead to celiac disease, wheat allergy, and non-celiac gluten sensitivity. The main treatment option is a gluten-free diet. Alternatively, using enzymes or microorganisms with gluten-degrading properties might alleviate the disease. These components can be used during food production or could be introduced into the digestive tract as food supplements. In addition, natural food from the environment is known to enrich the microbial communities in gut and natural environmental microbial communities have high potential to degrade gluten. It remains to be investigated if food and environment-induced changes in the gut microbiome could contribute to the triggering of gluten-related diseases. Key points • Wheat proteins, gluten, are incompletely digested in human digestive tract leading to gluten intolerance. • The only efficient treatment of gluten intolerance is life-long gluten-free diet. • Environmental bacteria acquired together with food could be source of gluten-degrading bacteria detoxifying undigested gluten peptides.

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Influx of Enterococci and Associated Antibiotic Resistance and Virulence Genes from Ready-To-Eat Food to the Human Digestive Tract

Applied and Environmental Microbiology ◽

10.1128/aem.01444-07 ◽

2007 ◽

Vol 73 (21) ◽

pp. 6740-6747 ◽

Cited By ~ 25

Author(s):

Lilia Macovei ◽

Ludek Zurek

Keyword(s):

Antibiotic Resistance ◽

Digestive Tract ◽

Fast Food ◽

Virulence Genes ◽

Food Contamination ◽

Gene Copy ◽

Marker Genes ◽

Enterococcus Casseliflavus ◽

Fast Food Restaurants ◽

Human Digestive Tract

ABSTRACT The influx of enterococcal antibiotic resistance (AR) and virulence genes from ready-to-eat food (RTEF) to the human digestive tract was assessed. Three RTEFs (chicken salad, chicken burger, and carrot cake) were sampled from five fast-food restaurants five times in summer (SU) and winter (WI). The prevalence of enterococci was significantly higher in SU (92.0% of salad samples and 64.0% of burger samples) than in WI (64.0% of salad samples and 24.0% of burger samples). The overall concentrations of enterococci during the two seasons were similar (∼103 CFU/g); the most prevalent were Enterococcus casseliflavus (41.5% of isolates) and Enterococcus hirae (41.5%) in WI and Enterococcus faecium (36.8%), E. casseliflavus (27.6%), and Enterococcus faecalis (22.4%) in SU. Resistance in WI was detected primarily to tetracycline (50.8%), ciprofloxacin (13.8%), and erythromycin (4.6%). SU isolates were resistant mainly to tetracycline (22.8%), erythromycin (22.1%), and kanamycin (13.0%). The most common tet gene was tet(M) (35.4% of WI isolates and 11.9% of SU isolates). The prevalence of virulence genes (gelE, asa1, cylA, and esp) and marker genes for clinical isolates (EF_0573, EF_0592, EF_0605, EF_1420, EF_2144, and pathogenicity island EF_0050) was low (≤12.3%). Genotyping of E. faecalis and E. faecium using pulsed-field gel electrophoresis revealed that the food contamination likely originated from various sources and that it was not clonal. Our conservative estimate (single AR gene copy per cell) for the influx of tet genes alone to the human digestive tract is 3.8 Ã¯Â¿Â½ 105 per meal (chicken salad). This AR gene influx is frequent because RTEFs are commonly consumed and that may play a role in the acquisition of AR determinants in the human digestive tract.

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