Fermented Portulaca oleracea L. Juice: A Novel Functional Beverage with Potential Ameliorating Effects on the Intestinal Inflammation and Epithelial Injury

Abstract

<i>P. oleracea</i> L. contains high level of nutrients and biologically active compounds. Recently, lactic fermentation has been proposed as a biotechnological option to enrich the profile of biogenic compounds of <i>Portulaca oleracea</i> L. puree. This study investigated the capability of fermentation by selected lactic acid bacteria to enhance the restoring features of <i>Portulaca oleracea</i> juice towards intestinal inflammation and epithelial injury. Lactic acid fermentation markedly increased the total antioxidant capacity of <i>P. oleracea</i> juice, preserved the inherent levels of vitamins C, A, and E, and increased the bioavailability of the level of vitamin B₂ and that of phenolics. The effects of fermented <i>P. oleracea</i> juice on a Caco-2 cell line were investigated using an in vitro model closest to the in vivo conditions. Fermented <i>P. oleracea</i> juice strongly decreased the levels of pro-inflammatory mediators and reactive oxygen species. It also counteracted the disruption of the Caco-2 cell monolayers treated with the inflammatory stimulus. We used a diversified spectrum of lactic acid bacteria species, and some effects appeared to be strains- or species-specific. Fermentation with <i>Lactobacillus kunkeei</i> B7 ensured the best combination for the content of bioactive compounds and the ability to counteract the intestinal inflammation and epithelial injury.