Inhibitory effect on lipid absorption and variability on chemical constituents from Capparis sicula subs. sicula and Capparis orientalis

In continuation of our research program on Mediterranean dietary plants, a bioassay-guided fractionation of extracts from several accessions of Capparis sicula subsp. sicula and Capparis orientalis aerial parts was carried out. Antilipidemic activity of samples was assayed using inhibition of pancreatic lipase. To study the metabolic variability in Capparis species, HPTLC analyses were performed in order to characterize the species through the detection, isolation, and quantitative evaluation of rutin taken as significant chemical marker. The best activity was exerted by C. orientalis accession no. C10 and C. sicula subsp. sicula accession no. C6. The bioactivity evaluation of specific chemical markers, rutin and glucocapparin, led to the identification of a potent antilipidemic compound rutin. The HPTLC analysis showed large variation among the different analyzed samples with respect to rutin concentration. The chemical investigation showed a different composition between the species and between the collection zones. The variations showed by the studied accessions of caper could be attributed to exogenous factors. Capparis species contained predominantly quercetin rutinoside (rutin), accompanied by other constituents such as the glucosinolate glucocapparin. These rutin-rich extracts exhibited pronounced dose-dependent enzyme inhibitory activities toward pancreatic lipase.