Correlation of in vitro digestibility with chemical composition and bioaccessibility of phenolic compounds in date pomace and antioxidant potential

Abstract

This study aimed to evaluate the chemical composition and impact of in vitro gastrointestinal digestion on the recovery, bioaccessibility, indices, and changes in the bioactive compounds of date pomace. Bioactive compounds were extracted using various solvents. The results revealed that pomace is a rich source of fiber. Methanol was found to be the most effective solvent for extraction of the bioactive compounds. A high recovery index for phenolic and flavonoid compounds and high antioxidant activity were obtained for the sample subjected to mouth-digestion. The bioaccessibility index revealed that a low percentage of phenols and flavonoids was available for absorption in the intestine. The TPC, TFC, and antioxidant activities (DPPH and ABTS) were positively correlated (r = 0.855-0.995) with oral, gastric, and intestinal digestion. Date pomace is an excellent source of bioactive compounds that can be utilized in the formulation of functional foods with health benefits.

Keywords

• Date pomace
• total phenolics
• antioxidant activity
• digestibility
• recovery
• bioaccessibility