Activity-guided fractionation of a methanolic extract of the leaves of Eremochloa ophiuroides (centipede grass) using a pancreatic lipase inhibitory assay led to the isolation and identification of a new C-glycosidic flavone, luteolin 6-C-b-D-boivinopyranoside (1), as well as eight known compounds. The structures of these compounds were established on the basis of interpretation of their spectroscopic data. Among these isolates, the C-glycosidic flavones 1–5 showed potent inhibitory effects on pancreatic lipase, with IC50 values ranging from 18.5 ± 2.6 to 50.5 ± 3.9 mM.
Activity-guided isolation of a methanolic extract of Galla Rhois using pancreatic lipase and 3T3-L1 adipocytes led to the isolation of seven phenolic compounds: protoaphin-fb (1), 2-O-digalloyl-1,3,4,6-tetra-O-galloyl-b-D-glucose (2), 1,2,3,4,6-penta-O-galloyl-b-D-glucose (3), 1,2,4,6-tetra-O-galloyl-b-D-glucose (4), 3-hydroxy-5-methoxy-phenol 1-O-b-D-glucoside (5), methylgallate (6), and gallic acid (7). Their structures were established on the basis of NMR and MS spectroscopic data interpretation. All isolates were evaluated for their inhibitory effects on pancreatic lipase, and compounds 1-5 exhibited potent inhibitory effects on this enzyme, with IC50 values ranging from 30.6 ± 2.4 to 3.5 ± 0.5 mM. In addition, the highly galloylated compound 2 was also found to induce potent inhibition of adipocyte differentiation in 3T3-L1 cells.
1 March 2014 in Bioorganic & Medicinal Chemistry Letters
Bioassay-guided isolation of an aqueous methanolic extract of Vitis vinifera using pancreatic lipase inhibitory activity led to isolation of seven stilbenoids, wilsonol C (1), heyneanol A (2), ampelopsin A (3), pallidol A (4), cis-piceid (5), trans-piceid (6) and trans-resveratrol (7). The structures were established on the basis of NMR and MS spectroscopic data interpretation. All isolates were evaluated for their inhibitory effects on pancreatic lipase, and stilbenoid 1 exhibited potent inhibitory effect on pancreatic lipase with IC50 values of 6.7 ± 0.7 µM.