Inhibition of angiotensin convertin enzyme (ACE) activity by the anthocyanins delphinidin- and cyanidin-3- O-sambubiosides from Hibiscus sabdariffa

• Published in: Journal of ethnopharmacology 2010-01, Vol.127 (1), p.7-10
• Main Authors: Ojeda, Deyanira, Jiménez-Ferrer, Enrique, Zamilpa, Alejandro, Herrera-Arellano, Armando, Tortoriello, Jaime, Alvarez, Laura
• Format: Article
• Language: English
• Subjects: Angiotensin-Converting Enzyme Inhibitors - pharmacology; Animals; Anthocyanins; Anthocyanins - chemistry; Anthocyanins - isolation & purification; Anthocyanins - pharmacology; Binding, Competitive; Biological and medical sciences; Chromatography, High Pressure Liquid; Disaccharides - chemistry; Disaccharides - isolation & purification; Disaccharides - pharmacology; Enzyme Inhibitors - chemistry; Enzyme Inhibitors - isolation & purification; Enzyme Inhibitors - pharmacology; Flowers - chemistry; General pharmacology; Hibiscus - chemistry; Hibiscus sabdariffa; Inhibition of angiotensin converting enzyme (IACE); Kinetics; Lung - enzymology; Malvaceae; Medical sciences; Medicine, Traditional; Mexico; Peptidyl-Dipeptidase A - metabolism; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; Phytotherapy; Plant Extracts - chemistry; Plant Extracts - pharmacology; Rabbits; Spectrum Analysis
• ISSN: 0378-8741; 1872-7573
• DOI: 10.1016/j.jep.2009.09.059

The beverages of Hibiscus sabdariffa calyces are widely used in Mexico as diuretic, for treating gastrointestinal disorders, liver diseases, fever, hypercholesterolemia and hypertension. Different works have demonstrated that Hibiscus sabdariffa extracts reduce blood pressure in humans, and recently, we demonstrated that this effect is due to angiotensin converting enzyme (ACE) inhibitor activity. The aim of the current study was to isolate and characterizer the constituents responsible of the ACE activity of the aqueous extract of Hibiscus sabdariffa. Bioassay-guided fractionation of the aqueous extract of dried calyces of Hibiscus sabdariffa using preparative reversed-phase HPLC, and the in vitro ACE Inhibition assay, as biological monitor model, were used for the isolation. The isolated compounds were characterized by spectroscopic methods. The anthocyanins delphinidin-3- O-sambubioside ( 1) and cyanidin-3- O-sambubioside ( 2) were isolated by bioassay-guided purification. These compounds showed IC 50 values (84.5 and 68.4 μg/mL, respectively), which are similar to those obtained by related flavonoid glycosides. Kinetic determinations suggested that these compounds inhibit the enzyme activity by competing with the substrate for the active site. The competitive ACE inhibitor activity of the anthocyanins 1 and 2 is reported for the first time. This activity is in good agreement with the folk medicinal use of Hibiscus sabdariffa calyces as antihypertensive.