In vitro activity of the F-6 fraction of oregano against Giardia intestinalis.
Giardiosis is a neglected parasitic disease that produces diarrhoea and different degrees of malabsorption in humans and animals. Its treatment is based on derivatives of 5-nitroimidazoles, benzimidazoles, nitrofuranes, acridine and nitrotiazoles. These drugs produce undesirable secondary effects, ranging from a metallic taste in the mouth to genetic damage and the selection of resistant strains; therefore, it is necessary to develop new therapeutic alternatives. We demonstrated that a 2-h treatment with 2·87 μg ml(-1) of fraction 6 of Lippia graveolens (F-6) was sufficient to kill half of an experimental Giardia intestinalis (Syn. G. duodenalis, G. lamblia) population, based on the reduction of MTT-tetrazolium salt levels. F-6 breaks the nuclear envelope and injures the ventral suckling disc. The major compounds of F-6 were characterized as naringenin, thymol, pinocembrin and traces of compounds not yet identified. The results suggest that Lippia is a potential source to obtain compounds with anti-Giardia activity. This knowledge is an important starting point to develop new anti-giardial drugs. Future studies will be required to establish the efficacy of F-6 in vivo using an animal model.
Parasitología experimental del Instituto Nacional de Pediatría, Insurgentes Sur no. 3700-C, CP 04530, México, DF, México.
Yadira
Y
Rufino-González
Martha
M
Ponce-Macotela
Angélica
A
González-Maciel
Rafael
R
Reynoso-Robles
Manuel
M
Jiménez-Estrada
Ángeles
Á
Sánchez-Contreras
Mario N
MN
Martínez-Gordillo
D000818:Animals; D016829:Giardia lamblia / Q000187:drug effects* / Q000648:ultrastructure; D006801:Humans; D032411:Lippia / Q000737:chemistry*; D008214:Lymphocytes / Q000187:drug effects; D046529:Microscopy, Electron, Transmission; D010084:Oxidation-Reduction; D021261:Parasitic Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D013778:Tetrazolium Salts / Q000378:metabolism
D010936:Plant Extracts; D013778:Tetrazolium Salts