Phenolic compounds and plant extracts as potential natural anti-obesity substances

Abstract

► Polyphenols and plant extracts inhibited the pancreatic lipase in an enzymatic assay. ► EGCG, quercetin and kaempferol were more potent than the antiobesity drug orlistat. ► Polyphenols were assayed in an in vitro model of simulated intestinal fat digestion. ► In those conditions closer to physiology, resveratrol was an effective inhibitor. ► Dietary polyphenols are valid candidates to obesity prevention. One strategy to prevent obesity could consist in the inhibition of the pancreatic lipase (PL). In an attempt to find natural antiobesity agents, phenolic compounds (PCs) and plant extracts were investigated on PL activity. Epigallocatechin-3-gallate > kaempferol and quercetin were detected as potent PL inhibitors, with ICs 50 of 0.8, 13.4 and 21.5 μM, respectively. Plant extracts from green tea and grape seed also shown potent inhibitory effect. Selected PCs were then assayed in an in vitro model of simulated intestinal fat digestion, based on the lipolysis of triolein. In such conditions closer to physiological reality, resveratrol, but also epigallocatechin-3-gallate and quercetin reduced the triolein digestion to ±50%. This could delay or decrease in vivo fatty acid absorption by enterocytes. This work therefore suggests that some PCs, at concentrations easily reached in the intestine following ingestion of tea beverages, fruits or vegetables, but also flavonoid-enriched supplements or functional food, are potential candidates for obesity prevention.