Impact of Simulated Gastrointestinal Digestion on the Bioaccessibility and Biological Activities of Lepidium sativum Phenolics: In Vitro and In Silico Insights

Abstract The current study sought to assess the effects of in vitro gastrointestinal digestion on Lepidium sativum seeds, focusing on the bioaccessibility of phenolic compounds and their biological activities, including antioxidant properties, α-amylase inhibition and acetylcholinesterase inhibitory potential. Molecular docking analyses were performed to provide insights into the binding interactions of the main components within the AChE active site. HPLC-DAD analysis identified seven phenolic compounds, among which caffeic acid was the predominant constituent (1.95 μg/g extract). In vitro gastric digestion enhanced the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity (measured by FRAP, ABTS, and DPPH assays) of the L. sativum seed extract. In contrast, α-amylase inhibitory potency decreased after gastric digestion and increased after intestinal digestion (IC50 = 85.17, 92.17, and 70.09 μg/mL for the undigested, gastric, and intestinal phases, respectively), whereas AChE inhibitory activity was markedly reduced following gastric digestion, with only partial recovery after the intestinal phase (IC50 = 96.76, 109.74, and 101.97 μg/mL for the undigested, gastric, and intestinal phases, respectively). Molecular docking predicted that several identified phenolic compounds displayed strong binding affinities toward AChE, with chlorogenic acid (−9.236 kcal/mol) and ellagic acid (−9.226 kcal/mol) showing values comparable to that of reference ligand (−9.100 kcal/mol). The integration of in vitro and in silico approaches indicates that L. sativum seed extracts may represent candidates of interest for further investigation as functional ingredients.