In vitro antiprotozoal activity from the roots of Geranium mexicanum and its constituents on Entamoeba histolytica and Giardia lamblia

J Ethnopharmacol. 2005 Apr 8;98(1-2):191-3. doi: 10.1016/j.jep.2005.01.019.

Abstract

This paper examines the antiprotozoal activity of the dichloromethane-MeOH extract, fractions and pure compounds from the roots of Geranium mexicanum on Entamoeba histolytica and Giardia lamblia. The result indicated that the extract, organic fraction and a pure flavonoid were active against both protozoa with IC50 values ranging from 1.9 to 79.2 microg/ml for Entamoeba histolytica and from 1.6 to 100.4 microg/ml in the case of Giardia lamblia. The main active compound was the flavan-3-ol, (-)-epicatechin. In addition, the moderate active compounds (+)-catechin, tyramine and beta-sitosterol 3-O-beta-D-glucopyranoside, also were isolated. These results support the anecdotal reports for the traditional use of Geranium mexicanum roots in the management of diarrhoea and dysentery, illnesses caused in some cases by enteric protozoa.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antiprotozoal Agents / chemistry
  • Antiprotozoal Agents / isolation & purification
  • Antiprotozoal Agents / pharmacology*
  • Catechin / chemistry
  • Catechin / isolation & purification
  • Catechin / pharmacology
  • Drug Evaluation, Preclinical / methods
  • Entamoeba histolytica / drug effects*
  • Ethanol / chemistry
  • Ethanol / isolation & purification
  • Ethanol / pharmacology
  • Flavonoids / chemistry
  • Flavonoids / isolation & purification
  • Geranium / chemistry*
  • Giardia lamblia / drug effects*
  • Glucosides / chemistry
  • Glucosides / isolation & purification
  • Inhibitory Concentration 50
  • Methylene Chloride / chemistry
  • Methylene Chloride / isolation & purification
  • Methylene Chloride / pharmacology
  • Plant Extracts / chemistry
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology
  • Plant Roots / chemistry*
  • Sitosterols / chemistry
  • Sitosterols / isolation & purification

Substances

  • Antiprotozoal Agents
  • Flavonoids
  • Glucosides
  • Plant Extracts
  • Sitosterols
  • sitosterol-3-O-glucopyranoside
  • flavan-3-ol
  • Ethanol
  • Methylene Chloride
  • gamma-sitosterol
  • Catechin