Antipancreatic Lipase and Intracellular Lipid‐Lowering Effect of Polyphenols Extract From Coix Seed

ABSTRACT Background and Objectives Coix seed polyphenols (CSPs) and their potential lipid‐lowering functions have been underexplored in scientific literature. The study aims to extract crude polyphenols from defatted Coix seeds using ethanol. Column chromatography was applied for further purification. After identifying and analyzing the structure and content of these polyphenols, we investigated their inhibitory effect on pancreatic lipase (PL) and related enzymatic kinetics. Additionally, we assessed their lipid‐lowering activity in an oleic acid‐induced high‐fat HepG2 cell model. Results In this study, we identified over 30 phenolic compounds in Coix seeds; the compounds with the highest proportions were followed by taxifolin, paeonol, neohesperidin dihydrochalcone (NHDC), (−)‐secoisolariciresinol, arbutin, and cyanidin chloride, reaching 2.14%, 2.02%, 1.63%, 1.38%, 1.36%, and 1.08%, respectively. These compounds accounted for 93.09% of the total CSP. CSP demonstrated significant inhibitory activity against PL, achieving an inhibition rate of 76.8% at a concentration of 2 mg/mL. Enzymatic kinetic analysis suggested that CSP exerts a typical mixed noncompetitive inhibitory effect on PL. In HepG2 cells induced with oleic acid, supplementation with 100 μg/mL CSP significantly reduced triglyceride, low‐density lipoprotein cholesterol, total cholesterol, aspartate aminotransferase, and alanine aminotransferase levels by 45.05%, 40.56%, 12.36%, 39.30%, and 28.49%, respectively ( p < .05). Conclusions These findings highlight the potential of CSP as a natural lipid‐lowering agent, warranting further exploration in functional foods and therapeutic applications.