Pigmented Grains as a Source of Immunomodulating Bioactives

INTRODUCTION Cereal products are consumed daily by a vast majority of the world population. Functional foods offer an opportunity to improve the quality of these products. In vitro and in vivo studies needed to provide evidences of the potential to develop enriched pasta as a functional food require improved focus on: a) reducing inflammatory responses; b) sensory traits; c) addressing their functional properties, and in particular the effects of prototype foods on oxidative status, on biomarkers of inflammation, and on the modulation of the gut microbiota. AIMS: Using purple wheat bran fractions to produce pasta incorporating nutritionally relevant amounts of fiber and anthocyanins, and testing the effects of the products of specific components on inflammation markers as well as on the intestinal microbiota. METHODS Pigmented grains were de-branned and milled in a lab-scale milling system. Extraction was conducted with ethanol:water (65:35 v/v) containing 0.01 % HCl. Analytical profiling of phenolics in fractions separated by physical techniques was carried out by HPLC. Antioxidant capacity was measured through the ferric reducing antioxidant power (FRAP). The LightSwitch transfection-ready, promoter reporter constructs were used to quantify repression in response to induction of the NFκB/Inflammation pathway in Caco-2 cells transfected with a reporter vector (pNiFty2-Luc). RESULTS Fraction R1 showed the highest amount of anthocianins with a relevant hight antioxidant activity. The ACN-rich fraction from purple wheat decreased the immune response of Caco-2 cells in a dose-responsive manner. The results also indicate that specific phenolic-rich fractions from pigmented wheat have stronger effect on lowering expression of inflammatory markers than a recognized standard (Cya) used at the same concentration (0.025 mM). HPLC-DAD profile of major components of anthocyanins in purple wheat bran fraction R1 . The major anthocyanins found are: A: Cyanidine 3-O-Glucoside B: Cyanidine 3-O- Rutinoside C: Delphinidin Chloride D: Peonidine 3-o-Glucoside E: Rutin (monitored at 350 nm) CONCLUSION The phenolics-rich fraction from pigmented grains appears to be at least twice more effective than standard cyaniding-3-glucoside in impairing the expression of inflammation marker in appropriately stimulated transformed cells. From a practical standpoint, it is noteworthy that the bioactive-rich fractions we obtained can be incorporated with minimal efforts and to a significant extent in ready-to consume staple foods, such as pasta. Further studies will address the bioavailability of the grain-derived anthocyanins and the amount of metabolites they form or release in the gastrointestinal tract, of their effects on the local microflora, and of the gut microflora interactions with the enriched foods.