PMC

Representative chromatograms (detection by UV/Vis) displaying the formation of piperine (1) at different substrate concentrations of piperoyl-CoA with piperine synthase (a–c), partly purified native piperine synthase activity (d), piperine standard (e), (2/3), isopiperine and chavicine, (4), piperic acid. SDS-PAGE of recombinant piperine synthase purification is shown as an insert. The position of the 55 kDa signal representing recombinant piperine synthase during purification is marked with an arrow.

HPLC and UPLC-Q-TOF-MS analysis of piperine. (A) HPLC results of standards piperine; (B) HPLC results of sample piperine extraction from white pepper; (C) UPLC-Q-TOF-MS results of standards piperine; (D) UPLC-Q-TOF-MS results of sample piperine extraction from white pepper; (E) ¹H NMR results of sample piperine extraction from white pepper; (F) Structural information of piperine extraction from white pepper.

(a) NMR titration of 400 μM of Piperine with increasing concentration of Pu24T. (b,c) Both of the stable conformation of Piperine with Pu24T obtained from docking by Autodock 4.0 in which Piperine is shown in yellow color as ball stick representation. Black dotted lines showing hydrogen bonds between Piperine and Pu24T.

Effect of piperine administration in VacA translocation and vacuolation. AGS cells were infected with H. pylori 60190 in the presence or absence of 100 μM of piperine for indicated period of time and harvested cell lysates were immunoblotted. A. Effect of piperine on VacA translocation. Piperine administration (100 μM) inhibits VacA translocation into AGS cells compared to piperine untreated, DMSO-treated H. pylori infection control. B-D. Effect of piperine on vacuolation. AGS cells were infected with H. pylori for 24 hours in the presence or absence of 100 μM of piperine and the cells were observed (400 ×) under the light microscope imaging. Piperine untreated H. pylori-infected cells have shown intense vacuoles inside of gastric adenocarcinoma cells, but 100 μM piperine administration restrains vacuolation completely. B. Uninfected. C. AGS cells infected with H. pylori 60190. D. AGS cells infected with H. pylori 60190 in the presence of 100 μM of piperine. The image is representative of three independent experiments.