Bioactives in pigmented grains: properties, activities, and incorporation into functional foods

Background: Grains as staples are good source of nutrients like carbohydrates, protein, lipids, vitamins, minerals and dietary phytochemicals such as phenolics, carotenoids, etc. Phenolic compounds have shown a broad range of biological activities. In this study, we have aimed to investigate the anthocyanin profile in diverse pigmented grains and to examine their bioactive molecules. to test on inflammation markers by using transfected Caco-2cells (with a vector pNiFty2-Luc) as a cell model, detecting their inhibitory activities against a-glucosidase and a-amylase enzymes, in order to select the appropriate grain to formulate functional food. Methods: Samples: Three varieties of corn and two varieties of wheat were used in this study. Methods: Ethanolic extracts acidified with 1.0 N HCl (65:35, v/v) was prepared. TAC and TPC was determined (Abdel Aal et al. (2006)). The FRAP assay was performed (Benzie and Strain (1996)). The major anthocyanins components were separated by HPLC (Hosseinian et al., 2008). The immunomodulatory activity of ACN-rich fractions was tested by using Caco-2 cell transfected model (Taverniti et al.,2014). Pancreatic α-amylase and intestinal α-glucosidase inhibitory activities were detected (Lavelli et al., 2016). Pasta making: Bioactive compounds-enriched pasta was prepared by adding 14.2 g/100g of anthocyanin-rich fraction of purple wheat to commercial flour, given us a pasta with greater nutritional value than the commercial durum wheat semolina pasta. Results: Purple wheat showed the highest TAC (690±0.02 µg/g), TPC (736±0.44 µg/g) and antioxidant activity (47.5 ±10.26 μmol Fe(II)/g) among all samples. The immune response of Caco-2 cells decreased for all grains extracts. Purple wheat and blue corn (cultivar T) extracts were much active to inhibit α-amylase enzyme. Enriched purple wheat pasta showed a relatively high antioxidant capacity. The anthocyanins content value ranged from 67.9±0.9 µg/g which is higher than values found by Ficco et al. (2016) in cooked pasta prepared from purple wholemeal semolina (16.89 µg/g). Extracts from cooked pasta showed noticeable Immunomodulatory effects. Conclusion: Naturally functional pasta prepared from purple wheat showed antioxidant and anti-inflammatory effects. Their use as daily food deserves further studies on their reported effects on cardiovascular risk factors, as well as their possible effects on the gut microflora. References: Nankar, Amol N., et al. "Quantitative and qualitative evaluation of kernel anthocyanins from southwestern United States blue corn." Journal of the Science of Food and Agriculture 96.13 (2016): 4542-4552. Huang, Bo, et al. "Anti-diabetic effect of purple corn extract on C57BL/KsJ db/db mice." Nutrition research and practice 9.1 (2015): 22-29. Tsuda, Takanori, et al. "Dietary cyanidin 3-O-β-D-glucoside-rich purple corn color prevents obesity and ameliorates hyperglycemia in mice." The Journal of nutrition 133.7 (2003): 2125-2130. Kim, Eun Ok, et al. "Anti-inflammatory activity of hydroxycinnamic acid derivatives isolated from corn bran in lipopolysaccharide-stimulated Raw 264.7 macrophages." Food and Chemical Toxicology 50.5 (2012): 1309-1316. Miguel, Maria Graça. "Anthocyanins: Antioxidant and/or anti-inflammatory activities." (2011). Ficco, D. B. M., De Simone, V., De Leonardis, A. M., Giovanniello, V., Del Nobile, M. A., Padalino, L., ... & De Vita, P. (2016). Use of purple durum wheat to produce naturally functional fresh and dry pasta. Food chemistry, 205, 187-195.