A novel synergistic inhibition mechanism of pancreatic lipase by 2-mercaptobenzothiazole and stearic acid migrants from dairy contact rubbers

This study explores the inhibitory effects of two migrants—2-mercaptobenzothiazole (MBT) and stearic acid—from dairy rubber contact materials on pancreatic lipase (PL). Enzyme assays showed significant, dose-dependent inhibition, with stearic acid being more potent. MBT and stearic acid exhibited reversible inhibition, with MBT acting competitively and stearic acid non-competitively. Fluorescence spectroscopy and circular dichroism indicated conformational changes in PL upon binding, while molecular docking confirmed specific interactions at the active site (MBT) and near it (stearic acid). Binding affinities for MBT-PL and stearic acid-PL complexes were − 24.90 and − 20.23 kJ/mol, respectively. High concentrations of both compounds exhibited synergistic inhibition, potentially affecting lipid digestion in dairy products. This study highlights the influence of rubber-derived migrants on PL activity and suggests limiting their use in food contact materials to safeguard dairy nutritional quality.