Bioaccessibility, in vitro antioxidant and anti-inflammatory activities of phenolics in cooked green lentil (Lens culinaris)

The bioaccessibility, antioxidant and anti-inflammatory activities of phenolics in a cooked green lentil (Lens culinaris) (cultivar Greenland) was studied using a simulated upper gastrointestinal (UGI) digestion model combined with chemical- and cell- based antioxidant assays. The amount of released soluble phenolics increased stepwise from gastric to intestinal digestion phase. The bioaccessibility of phenolics ranged from 27 to 67% after UGI digestion. Flavonols were the main phenolic group and were found to remain relatively stable during UGI digestion. Flavanols were mainly released after intestinal digestion as opposed to phenolic acids which were mainly released from food matrix in the gastric phase (21-45%) but not detected following intestinal digestion. Phenolics of the nondigested lentil showed dose dependent anti-inflammatory activity as seen in significant inhibition of the pro-inflammatory cytokines COX-2, IL-1β and IL-6 in TNF-α-induced inflammation in Caco-2 cells. The Antioxidant and anti-inflammatory activities were positively correlated with the total and individual phenolic contents.