The Western diet can negatively affect the gut microbiota and is associated with metabolic disorders. Kombucha, a tea fermented by a symbiotic culture of bacteria and yeast (SCOBY), is known for its bioactive properties and has become popular in the last years. In this study, we evaluated the effects of regular kombucha consumption on the gut microbiota and on outcomes related to the intestinal health of Wistar rats fed a high-fat high-fructose diet. After eight weeks receiving a standard diet (AIN-93M) (n = 10) or a high-fat and high-fructose diet (HFHF) (n = 30) to induce metabolic disorders, the animals were subdivided into four groups: AIN-93M (n = 10); HFHF (n = 10); GTK (HFHF + green tea kombucha (n = 10); and BTK (HFHF + black tea kombucha; n = 10) for 10 weeks. Although body composition did not differ among the groups, the HFHF diet was associated with metabolic alterations, and stimulated the growth of gram-negative bacteria such as Proteobacteria and Bacteroides. Kombucha ingestion could somewhat modulate the gut microbiota, attenuating the effects of a Western diet by increasing propionate production and favoring the growth of beneficial bacteria, such as Adlercreutzia in the GTK group. Our results suggest that regular kombucha consumption may be beneficial to intestinal health, which can be mostly attributed to its high content and diversity of phenolic compounds.

A direct correlation has been reported between excessive fat intake and the development and progression of various enteropathies. Plant foods may contain bioactive compounds and non-digestible dietary fiber, with potential to improve intestinal health. Chia is a good source of dietary fiber and bioactive compounds. Our study evaluated the role of chia flour associated with a high-fat diet (HFD) on colon histomorphometry, intestinal functionality and intestinal microbiome composition and function in Wistar rats. The study used 32 young male rats separated into four groups to receive a standard diet (SD) or HFD, with or without chia, for 35 days. At the end of the study, the cecum, cecal content and duodenum were collected. The consumption of chia increased the production of short-chain fatty acids and improved fecal moisture. Chia consumption improved the circular muscle layer in the SD group. The diversity and abundance of intestinal bacteria were not affected, but increased richness was observed in the microbiome of the SD+chia group. Moreover, chia consumption decreased the expression of proteins involved in intestinal functionality. Chia consumption improved intestinal morphology and functionality in young Wistar rats but was insufficient to promote significant changes in the intestinal microbiome in a short term of 35 days.

(1) Background: This study aimed to evaluate the effect of an extruded whole-grain sorghum beverage containing L. paracasei on body composition, lipid profiles, and intestinal health in overweight and obese adults. (2) Methods: A chronic, single-blind randomized controlled pilot study was conducted with 30 volunteers allocated to three groups (n = 10/group): extruded sorghum beverage (ESB), extruded sorghum beverage with L. paracasei (ESPB), and control beverage (CB) (waxy maize starch). The chemical composition of the beverages was analyzed. Volunteers consumed the beverages for ten weeks at breakfast, along with individual dietary prescriptions. Body composition, biochemical markers, gastrointestinal symptoms, stool consistency, intestinal permeability, short-chain fatty acids, fecal pH, and stool L. paracasei DNA concentration were analyzed at the beginning and end of the intervention period. (3) Results: The ESB showed better composition than the CB, particularly in terms of resistant starch content, total phenolic compounds, condensed tannins, and antioxidant capacity. Both the ESB and the ESPB had an effect on body composition (estimated total visceral fat and waist volume), biochemical markers (Castelli index I), and intestinal health (Bristol scale, diarrhea score, valeric acid, and L. paracasei DNA concentration). No changes were observed in the CB group after the intervention. (4) Conclusions: Whole-grain sorghum beverages demonstrated good nutritional value, and consumption of these beverages, with or without L. paracasei, provided health benefits, including improvements in body composition, Castelli index I scores, and intestinal health, in overweight and obese adults.

This study evaluated the effect of pearl millet subjected to different processing on the intestinal health of rats. The animals were fed a standard iron-free diet (28 days) (hemoglobin depletion: 8.65 + 1.40 g/dL of hemoglobin). Subsequently, they were divided into four groups for hemoglobin repletion (21 days): standard diet + ferrous sulfate (SD + FS); standard diet + non-germinated open-pan cooked millet flour (SD + NGOPCMF); standard diet + germinated open-pan cooked millet flour (SD + GOPCMF); and standard diet + extrusion-cooked millet flour (SD + ECMF). Hemoglobin level did not differ among groups. The SD + NGOPCMF, SD + GOPCMF and SD + ECMF groups demonstrated a higher Chao index in the microbiome and a higher number and area of goblet cells and longitudinal muscle layer width. The SD + NGOPCMF and SD + GOPCMF groups demonstrated increased cecum weight, crypt depth, crypt thickness, and circular muscle layer width; lower fecal pH; and a higher relative abundance of Bacteroidota, while the SD + FS group showed the highest abundance of Actinobacteriota. The SD + GOPCMF group stood out for showing the lowest fecal pH, better α-diversity (Chao and Shannon index), and the highest width of the longitudinal muscle layer. In conclusion, pearl millet subjected to different processing, mainly germination, has the potential to improve the composition of the intestinal microbiota and the intestinal morphology in rats induced to iron deficiency.

Phenolic compounds can act as a substrate for colonic resident microbiota. Once the metabolites are absorbed and distributed throughout the body, they can have diverse effects on the gut. The objective of this study was to evaluate the effects of the intra-amniotic administration of a chia phenolic extract on intestinal inflammation, intestinal barrier, brush border membrane functionality, intestinal microbiota, and morphology in vivo (Gallus gallus model). Cornish-cross fertile broiler eggs, at 17 days of embryonic incubation, were separated into groups as follows: non-injected (NI; this group did not receive an injection); 18 MΩ H₂O (H₂O; injected with ultrapure water), and 10 mg/mL (1%) chia phenolic extract (CPE; injected with phenolic extract diluted in ultrapure water). Immediately after hatch (21 days), chickens were euthanized and their small intestine, cecum, and cecum content were collected and analyzed. The chia phenolic extract reduced the tumor necrosis factor-alpha (TNF-α) and increased the sucrose isomaltase (SI) gene expression, reduced the Bifidobacterium and E. coli populations, reduced the Paneth cell diameter, increased depth crypt, and maintained villus height compared to the non-injected control group. Chia phenolic extract may be a promising beneficial compound for improving intestinal health, demonstrating positive changes in intestinal inflammation, functionality, microbiota, and morphology.

Anthocyanins, a class of polyphenolic compounds widely present in berries and tropical fruits, have been increasingly investigated for their role in gut-liver axis. This systematic review synthesized evidence from preclinical studies evaluating the effects of anthocyanin-rich fruits on inflammation and oxidative stress, as well as secondary outcomes related to liver and intestinal function. Searches for original articles were performed in PubMed, Scopus, Web of Science, and Embase. A total of 18 studies were selected. Overall, supplementation with anthocyanin-rich fruits reduced pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), enhanced antioxidant enzyme activities (SOD, GPx, CAT), and lowered lipid peroxidation (MDA). These primary outcomes were consistently associated with improvements in liver health, including decreased serum ALT and AST, reduced steatosis, and lower histological damage. At the intestinal level, anthocyanins increased the expression of tight junction proteins (ZO-1, occludin), reduced permeability, and promoted favorable microbial shifts, particularly an enrichment of Lactobacillus, Bifidobacterium, and Akkermansia muciniphila. The gut-liver axis emerged as a central mediator, contributing to systemic anti-inflammatory and metabolic benefits. Collectively, the findings highlight the potential of anthocyanin-rich fruits as dietary strategies to prevent or mitigate metabolic and inflammatory disorders through coordinated modulation of intestinal and hepatic pathways.