Purpose: Procyanidins have strong potential for antioxidation and decreasing hepatic fat accumulation thus preventing non-alcoholic fatty liver disease (NAFLD). Procyanidin A2 (PCA2), predominately found in cranberries, avocado, peanut red skins and litchi fruit pericarp, is poorly absorbed in the gastrointestinal tract. However, literatures about its metabolic profile by gut microbiota and effects on lipid metabolism are limited. Therefore, the metabolites of PCA2 by human intestinal microbiota as well as their antioxidant and hypolipidemic potential were investigated. 

Methods: PCA2 was incubated with human intestinal microbiota and the metabolites produced were characterized by UPLC-Q-TOF-MS. The antioxidant and hypolipidemic potential of PCA2 and its microbial metabolites (MPCA2) were evaluated and compared. 

Results: The metabolism of PCA2 resulted in the formation of 14 metabolites, and the highest antioxidant capacity values were reached after 6 h incubation. In addition, PCA2 and MPCA2 were effective in reducing oxidative stress and lipid accumulation induced by oleic acid (OA) in HepG2 cells. They significantly promoted the phosphorylation of AMP-activated protein kinase (AMPK) and thus stimulated hepatic lipolysis by up-regulating of the expression of carnitine palmitoyl transferase I (CPT-I) and suppressed hepatic lipogenesis by down-regulation of the expression of 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMG-CoA) reductase, fatty acid synthase (FAS) and sterol regulatory element binding proteins 1c (SREBP-1c). 

Conclusion: Our results indicated that PCA2 and MPCA2 were effective to prevent OA-induced lipid accumulation and oxidative stress in HepG2 cells, implying that microbial metabolites may play a crucial role in the realization of human health effects of PCA2.

The search has been ongoing for safe and effective antimicrobial agents for control and prevention of oral biofilm associated with disease. Clinical trials for oral specific anti-bacterials are costly and often provide inconclusive results. The simple approach of ex vivo testing of these agents has not demonstrated utility, likely due to variability of effects observed even with a single donor. We show how shed oral biofilms, easily obtained from donor saliva, and tested under optimized conditions, respond reproducibly to anti-bacterial challenges measured by reductions in rRNA accumulation in susceptible taxa. Responses are in part donor specific, but many bacteria taxa were shown to be reproducibly susceptible over a group of donors. For two antibiotics, vancomycin and penicillin G tested at pharmacologic levels, a subset of Gram-positive bacteria was inhibited. A natural product with antibacterial properties, diluted Vaccinium macrocarpon (cranberry) juice, was shown to inhibit a range of oral taxa, including Alloprevotella sp__HMT_473, Granulicatella adiacens, Lachnoanaerobaculum umeaense, Lepotrichia sp__HMT_215, Peptostreptococcus stomatis, Prevotella nanceiensis, Stomatobaculum sp__HMT_097, Veillonella parvula, and kill some targets. The model discussed in this study has promise as a rapid, precise, and reproducible ex vivo method to test and identify potential clinically useful antimicrobial agents active against the oral biofilm community.

Dietary polyphenols are garnering attention in the scientific community due to their potential health-beneficial properties and preventative effects against chronic diseases, viz. cardiovascular diseases, diabetes, obesity, and neurodegenerative diseases. Polyphenols are antioxidants that change microbial composition by suppressing pathogenic bacteria and stimulating beneficial bacteria. The interaction of polyphenols with dietary fibers affects their bioaccessibility in the upper and lower parts of the digestive tract. Dietary fibers, polyphenols, their conjugates, and their metabolites modulate microbiome population and diversity. Consuming polyphenol-rich dietary fibers such as pomegranate, cranberry, berries, and tea improves gut health. A complex relationship exists between polyphenol-rich diets and gut microbiota for functioning in human health. In this review, we provide an overview of the interactions of dietary polyphenols, fibers, and gut microbiota, improving the understanding of the functional properties of dietary polyphenols.

Objective The dietary index for gut microbiota. DI-GM is an innovative metric designed to capture the diversity of the gut microbiome, yet its association with constipation remains unstudied. 

Methods In this cross-sectional study, 11,405 adults aged 20 and older were selected from the National Health and Nutrition Examination Survey 2005–2010 for the sample. Constipation was defined as fewer than three defecation frequencies per week using bowel health questionnaire (BHQ). Fewer than three bowel movements per week were considered as constipation by Bowel Health Questionnaire (BHQ). DI-GM was derived from dietary recall data, including avocado, broccoli, chickpeas, coffee, cranberries, fermented dairy, fiber, green tea, soybean and whole grains as beneficial elements, red meat, processed meat, refined grains, and high fat as detrimental components. Multivariable weighted logistic was employed to investigate the association of DI-GM with constipation. Secondary analyses included subgroup analyses, restricted cubic spline (RCS), and multiple imputation. 

Results A higher DI-GM and beneficial gut microbiota score were associated with a lower prevalence of constipation (DI-GM: OR = 0.82, 95% CI = 0.75, 0.90; beneficial gut microbiota score: OR = 0.77, 95% CI = 0.67, 0.89). After grouping DI-GM, in the fully adjusted model, participants with DI-GM ≥ 6 were significantly negatively correlated with both the prevalence of constipation (OR = 0.48, 95% CI = 0.33, 0.71). RCS indicated a non-linear relationship between DI-GM and constipation. Subgroup analyses by age, sex and common complications showed no statistically significant interactions (p > 0.05). 

Conclusion The newly proposed DI-GM was inversely related with the prevalence of constipation. When treating patients with constipation, it is necessary for clinicians to provide timely and effective dietary interventions incorporating the DI-GM for patients with constipation to avoid further deterioration of the condition.

Purpose of review: Berries are a great source of fiber, polyunsaturated fatty acids, and beneficial secondary metabolites (polyphenols). Various phytochemicals present in berries (glycosidic-linked flavonoids, anthocyanins, etc.) provide potential health benefits to consumers. Berries are known as high antioxidant food which provides certain cellular and molecular protection thereby lower rates of obesity and chronic disease risk. Molecular-level mechanisms protect a cell, while cellular mechanism considers all molecular units. For example, polyphenols found in blueberries have the potential to significantly reduce adipogenesis. Therefore, in continuation with part I, this review part II summarizes recent updates on the nutritional composition and biological activities of caperberry, chokeberry, cloudberry, cranberry, elderberry, gooseberry, goji berry, and lingonberry. 

Recent findings: These berries contain higher amounts of dietary fiber, protein, polyphenols, vitamins, minerals, and lipids. Besides, their antioxidant and anti-inflammatory activities, these berries are reported for eye health, brain health, cardiovascular health, anti-diabetic, etc. The consumption of a summarized group of berries could be more beneficial for eye health, mental health, and metabolic health thereby enhancing the well-being of the consumers.