Pancreatic lipase and cholesterol esterase inhibitory effect of Camellia nitidissima Chi flower extracts in vitro and in vivo

Camellia nitidissima Chi is an edible medicinal plant that has potential antiobesity effects. However, the underlying mechanism is unclear. The results showed that Camellia nitidissima Chi flower extracts (CNFE) had a strong inhibitory effect on pancreatic lipase (PL), pancreatic cholesterol esterase (CEase) and cholesterol micellization in a significant dose-dependent manner. The IC50 of PL, CEase, and cholesterol solubility were 320, 200, and 600 mu g/mL, respectively. Kinetic analysis showed that CNFE inhibited PL and CEase activity as a noncompetitive inhibitor. CNFE changed the microenvironment and conformation of both enzymes, which caused a decrease in enzymatic activities. Furthermore, experiments in rats showed that CNFE effectively reduced food intake and increased feces total triglycerides and total cholesterol excretion. These results not only highlight the inhibitory effect of CNFE against PL and CEase in vitro and in vivo, but also provide a starting point for the application of CNFE in weight reduction programs.