Catechin-based procyanidins from Peumus boldus Mol. aqueous extract inhibit Helicobacter pylori urease and adherence to adenocarcinoma gastric cells.
In this work, the anti-Helicobacter pylori effect of an aqueous extract from dried leaves of Peumus boldus Mol. (Monimiaceae) was evaluated. This extract displayed high inhibitory activity against H. pylori urease. Therefore, in order to clarify the type of substances responsible for such effect, a bioassay-guided fractionation strategy was carried out. The active compounds in the fractions were characterized through different chromatographic methods (RP-HPLC; HILIC-HPLC). The fraction named F5 (mDP = 7.8) from aqueous extract was the most active against H. pylori urease with an IC50  = 15.9 µg gallic acid equivalents (GAE)/mL. HPLC analysis evidenced that F5 was composed mainly by catechin-derived proanthocyanidins (LC-MS and phloroglucinolysis). The anti-adherent effect of boldo was assessed by co-culture of H. pylori and AGS cells. Both the aqueous extract and F5 showed an anti-adherent effect in a concentration-dependent manner. An 89.3% of inhibition was reached at 2.0 mg GAE/mL of boldo extract. In conjunction, our results suggest that boldo extract has a potent anti-urease activity and anti-adherent effect against H. pylori, properties directly linked with the presence of catechin-derived proanthocyanidins.
Laboratory of Pharmacognosy, Department of Pharmacy, Faculty of Pharmacy, University of Concepción, Concepción, Chile.
Edgar
E
Pastene
Víctor
V
Parada
Marcia
M
Avello
Antonieta
A
Ruiz
Apolinaria
A
García
D000230:Adenocarcinoma; D001422:Bacterial Adhesion / Q000187:drug effects*; D044946:Biflavonoids / Q000494:pharmacology*; D002392:Catechin / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016480:Helicobacter pylori / Q000187:drug effects* / Q000201:enzymology; D006801:Humans; D020128:Inhibitory Concentration 50; D008826:Microbial Sensitivity Tests; D031611:Peumus / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D059808:Polyphenols / Q000737:chemistry; D044945:Proanthocyanidins / Q000494:pharmacology*; D014510:Urease / Q000037:antagonists & inhibitors*
D044946:Biflavonoids; D004791:Enzyme Inhibitors; D010936:Plant Extracts; D059808:Polyphenols; D044945:Proanthocyanidins; C017674:procyanidin; D002392:Catechin; D014510:Urease
Helicobacter pylori; Peumus boldus; polyphenols; proanthocyanidins; urease