Trimethylamine N-oxide (TMAO) is considered a novel risk factor for cardiovascular diseases. Several studies demonstrated that polyphenols are able to inhibit the growth of TMA-producing bacterial strains, and resveratrol (RSV) reduced TMAO levels in mice. In the present study, we evaluated the TMAO-reducing effect of a novel nutraceutical formulation containing grape pomace extract in humans (Taurisolo^®). The Taurisolo^® polyphenol content was evaluated by a High Performance Liquid Chromatography-diode-array detector (HPLC-DAD) method, and RSV was monitored as an indicative marker. After in vitro GI digestion, intestinal bioaccessibility of RSV was 92.3%. A randomized, placebo-controlled, cross-over trial was carried out to evaluate the TMAO-reducing effect of Taurisolo^®. In acute, the maximum levels of RSV were detected both in serum and whole blood 60 min after the administration of Taurisolo^®; in chronic, a significant increase of RSV was detected in serum after the 4-week treatment. After 4 weeks, the levels of TMAO were significantly decreased in the treatment group compared to placebo (63.6% vs. 0.54%, respectively, P < 0.0001). In conclusion, our data show that Taurisolo^® may represent a novel and useful natural remedy to reduce prognostic markers for incident cardiovascular events. Undoubtedly, further in vitro and in vivo studies need to be performed in order to elucidate possible mechanisms of action and corroborate our preliminary results.

The beneficial effects of the tea beverage are well-known and mainly attributed to polyphenols which, however, have poor bioaccessibility and bioavailability. The purpose of the present study was the evaluation of colon bioaccessibility and antioxidant activity of tea polyphenolic extract. An 80% methanolic extract (v/v) of tea polyphenols was obtained from green (GT), white (WT) and black tea (BT). Simulated gastrointestinal (GI) digestion was performed on acid-resistant capsules containing tea polyphenolic extract. The main tea polyphenols were monitored by HPLC-diode-array detector (DAD) method; in addition, Total Phenol Content (TPC) and antioxidant activity were evaluated. After GI digestion, the bioaccessibility in the colon stage was significantly increased compared to the duodenal stage for both tea polyphenols and TPC. Similarly, the antioxidant activity in the colon stage was significantly higher than that in the duodenal stage. Reasonably, these results could be attributable in vivo to the activity of gut microbiota, which is able to metabolize these compounds, generating metabolites with a greater antioxidant activity. Our results may guide the comprehension of the colon digestion of polyphenols, suggesting that, although poorly absorbed in the duodenum, they can exert their antioxidant and anti-inflammatory activities in the lower gut, resulting in a novel strategy for the management of gut-related inflammatory diseases.

Emerging evidence suggests that fermentation, historically used for the preservation of perishable foods, may be considered as a useful tool for increasing the nutritional value of fermented products, in terms of increases in bioactive compound content, including short-chain fatty acids (SCFAs), as bacteria end-products, whose beneficial effects on human health are well-established. The purpose of the present manuscript is to summarize studies in this field, providing evidence about this novel potential of fermentation. A limited number of studies directly investigated the increased SCFA levels in fermented foods. All studies, however, agree in confirming that levels of SCFAs in fermented products are higher than in unfermented products, recognizing the key role played by the microorganisms in metabolizing food matrices, producing and releasing bioactive substances. According to the available literature, fermentation might be taken into account by the food industry as a natural strategy with no environmental impacts to produce functional foods and beverages with a higher nutritional value and health-promoting compounds.

The herpes simplex virus (HSV) is a common human virus affecting many people worldwide. HSV infections manifest with lesions that occur in different parts of the body, including oral, ocular, nasal, and genital skin and mucosa. In rare cases, HSV infections can be serious and lethal. Several anti-HSV drugs have been developed, but the existence of mutant viruses resistant to these drugs led to the individuation of novel antiviral agents. Plant-derived bioactive compounds, and more specifically polyphenols, have been demonstrated to exert marked anti-HSV activity and, among these, resveratrol (RSV) would be considered a good candidate. The purpose of this manuscript is to review the available literature elucidating the efficacy of RSV against HSV and the main demonstrated mechanisms of action.

The coronavirus infection is constantly diffusing worldwide and the incidence of death is dramatically increasing, representing one of the greatest disasters in human history. Nowadays, no effective therapeutic approaches have been licensed, despite the rising interest of the scientific research in this specific field, and the daily growing number of publications, while the need to find novel strategies is urgent. Evidence in the literature reported the antiviral activity of polyphenols, the largest class of bioactive compounds in nature. Interestingly, a limited number of studies investigated the efficacy of polyphenols from different raw materials, directly against coronaviruses. The present manuscript aimed to report this evidence and provide a viewpoint on the possibility to use it as a start point for the development of novel natural approaches against this viral infection, eventually designing further appropriate researches.