Metabolic flux and catabolic kinetics of prebiotic-like dietary polyphenol phlorizin in association with gut microbiota in vitro

The dynamics impact of phlorizin on gut microbiota and metabolites in an in vitro fermentation model

The multiple beneficial effects, but low bioavailability of phlorizin (PHZ) have sparked discussion about its role in interaction with the gut microbiota. In this study, the effects of PHZ on the fecal microbiota animals of different origins were investigated using an in vitro fermentation model. In the fermentation system of PHZ using SD rat feces, the dynamic variations of the bacterial profile, SCFAs, and organic acids were detected using 16S rRNA gene sequencing, GC-MS, and LC-MS/MS. The results showed that PHZ treatment significantly increased the phylum Bacteroidota and transiently reduced Firmicutes at 6 h. At the genus level, PHZ consistently increased the abundance of Lactobacillus (especially Lactobacillus johnsonii), significantly decreased the abundance of Ligilactobacillus and Limosilactobacillus, and temporarily suppressed Streptococcus after 12 h. Similarly, in the fermentation system using db/db mouse feces, PHZ enriched the abundance of Lactobacillus and Lactobacillus johnsonii. Monoculture of Lactobacillus johnsonii ATCC 33200 showed that PHZ could directly stimulate its growth. Meanwhile, we found that PHZ could significantly increase the production of butyric, isobutyric, isovaleric, valeric, and caproic acids. Organic acid analysis showed an increasing trend in succinic acid and a significant reduction in L-malic acid in the post-PHZ group. Correlation analysis revealed that the abundance of Lactobacillus positively correlated with the concentration of SCFAs and succinic acid, while negatively correlated with L-malic acid. These findings suggest that PHZ may regulate intestinal balance by promoting Lactobacillus johnsonii growth and modulating SCFA and specific organic acid levels. Our study highlights that natural polyphenol PHZ has a health-promoting potential by modulating gut microbiota.

Cooperation mechanism of flavonoid transformation by Bifidobacterium animalis subsp. lactis and Lacticaseibacillus paracasei

Elaeagnus moorcroftii Wall. ex Schlecht (EWS) as a suitable food matrix contains abundant flavonoids for promoting human health, this study aimed to use flavonoid-targeted metabolomics and transcriptome sequencing to investigate the transformation of flavonoids in EWS juice (EWSJ) by mono- and mixed-cultures fermentations of Bifidobacterium animalis subsp. lactis HN-3 (B.an3) and Lacticaseibacillus paracasei YL-29 (L.cp29). A total of 33 flavonoids were identified in mono- and mixed-cultures fermented EWSJ. Among them, fermentation by B.an3 produced specific deglycosylation products (kaempferol (17.6 mmol/L) and luteolin (4.5 mmol/L)) and methoxylation products (syringaldehyde (59.05 mmol/L)), and fermentation by L.cp29 resulted in a specific deglycosylation product (quercetin (9.2 mmol/L)). The co-culture fermentation further increased the levels of isorhamnetin (52.3 mmol/L), and produced a specific product (homoplantaginin (0.03 mmol/L)), which significantly increased the bioactive-form flavonoids. Moreover, we analyzed changes in different flavonoid metabolites and differential genes before and after fermentation. After L.cp29 fermentation the expression of glycoside hydrolases and oxidoreductases were increased compared to other groups. After B.an3 fermentation the expression of isomerases and synthetases were increased compared to other groups. In particular, 6-phosphogluconolactonase (Pgl) and glucose-6-phosphate isomerase (Pgi) were increased in B.an3 fermentation. Thus, we validated the predicted transformation reactions by the biotransformation of flavonoids by the collected strains and crude enzyme extracts of B.an3 and L.cp29. These findings provided a basis for the development of functional plant-based foods with enhanced bioactive flavonoids.

Different polysaccharide-enhanced probiotic and polyphenol dual-functional factor co-encapsulated microcapsules demonstrate acute colitis alleviation efficacy and food fortification

Probiotics and polyphenols have multiple bioactivities, and developing co-encapsulated microcapsules (CM) is a novel strategy to enhance their nutritional diversity. However, the development of CMs is challenged by complicated processing, single types, and unclear in vivo effects and applications. In this study, the co-microencapsulations of polyphenol and probiotic were constructed using pectin, alginate (WGCA@LK), and Fu brick tea polysaccharides (WGCF@LK), respectively, with chitosan-whey isolate proteins by layer-by-layer coacervation reaction, and their protective effects, in vivo effectiveness, and application potential were evaluated. WGCA@LK improved the encapsulation rate of polyphenols (42.41 %), and remained high viability of probiotics after passing through gastric acidic environment (8.79 ± 0.04 log CFU/g) and storage for 4 weeks (4.59 ± 0.06 log CFU/g). WGCF@LK exhibited the highest total antioxidant activity (19.40 ± 0.25 μmol/mL) and its prebiotic activity removed the restriction on probiotic growth. WGCA@LK showed strong in vitro colonic adhesion, but WGCF@LK promoted in vivo retention of probiotics at 48 h. WGCF@LK showed excellent anti-inflammatory effects and alleviated symptoms of acute colitis in mice. These findings provide unique insights into the fortification of probiotic-polyphenol CMs by different polysaccharides and the development of novel health foods with rich functional hierarchies and superior therapeutic effects.

Gut-Brain Axis in Focus: Polyphenols, Microbiota, and Their Influence on α-Synuclein in Parkinson's Disease

With the recognition of the importance of the gut-brain axis in Parkinson's disease (PD) etiology, there is increased interest in developing therapeutic strategies that target α-synuclein, the hallmark abhorrent protein of PD pathogenesis, which may originate in the gut. Research has demonstrated that inhibiting the aggregation, oligomerization, and fibrillation of α-synuclein are key strategies for disease modification. Polyphenols, which are rich in fruits and vegetables, are drawing attention for their potential role in this context. In this paper, we reviewed how polyphenols influence the composition and functional capabilities of the gut microbiota and how the resulting microbial metabolites of polyphenols may potentially enhance the modulation of α-synuclein aggregation. Understanding the interaction between polyphenols and gut microbiota and identifying which specific microbes may enhance the efficacy of polyphenols is crucial for developing therapeutic strategies and precision nutrition based on the microbiome.

Schisandra chinensis Bee Pollen Ameliorates Colitis in Mice by Modulating Gut Microbiota and Regulating Treg/Th17 Balance

Colitis is a chronic disease associated with alterations in the composition of gut microbiota. Schisandra chinensis bee pollen extract (SCPE) has been proved to be rich in phenolic compounds and effective in modulating gut microbiota, but its effect on colitis and the underlying mechanism remains unclear. This study investigates the relationship between colitis amelioration and the gut microbiota regulation of SCPE via fecal microbial transplantation (FMT). The results showed that administration of 20.4 g/kg BW of SCPE could primely ameliorate colitis induced by dextran sulfate sodium (DSS) in mice, showing as more integration of colon tissue structure and the colonic epithelial barrier, as well as lower oxidative stress and inflammation levels compared with colitis mice. Moreover, SCPE supplement restored the balance of T regulatory (Treg) cells and T helper 17 (Th17) cells. Gut microbiota analysis showed SCPE treatment could reshape the gut microbiota balance and improve the abundance of gut microbiota, especially the beneficial bacteria (Akkermansia and Lactobacillus) related to the production of short-chain fatty acids and the regulation of immunity. Most importantly, the protection of 20.4 g/kg BW of SCPE on colitis can be perfectly transmitted by fecal microbiota. Therefore, the gut microbiota-SCFAS-Treg/Th17 axis can be the main mechanism for SCPE to ameliorate colitis. This study suggests that SCPE can be a new promising functional food for prevention and treatment of colitis by reshaping gut microbiota and regulating gut immunity.