Plant species used in giardiasis treatment: ethnopharmacology and in vitro evaluation of anti-Giardia activity

• Published in: Revista brasileira de farmacognosia Vol. 24; no. 2; pp. 215 - 224
• Main Authors: Neiva, Vanessa do A., Ribeiro, Maria Nilce S., Nascimento, Flávia R.F., Cartágenes, Maria do Socorro S., Coutinho-Moraes, Denise F., Amaral, Flavia M.M. do
• Format: Journal Article
• Language: English
• Published: Elsevier Editora Ltda 01.03.2014; Sociedade Brasileira de Farmacognosia
• Subjects: Ethnopharmacology; Giardia lamblia; Giardicidal activity; In vitro; Medicinal plants; PHARMACOLOGY & PHARMACY; Medicinal plants; Ethnopharmacology; Giardia lamblia; Giardicidal activity; In vitro
• ISSN: 0102-695X; 1981-528X; 1981-528X
• DOI: 10.1016/j.bjp.2014.04.004

The aim of this study was to compile the traditional knowledge about plants used for the treatment of giardiasis, and also to carry out experimental research to evaluate the anti-Giardia activity of five species.To reach this objective, 398 interviews were performed using a previously prepared questionnaire, followed by an in vitro evaluation of giardicidal potential of hydroalcoholic leaf extracts of Anacardium occidentale L., Chenopodium ambrosioides L., Passiflora edulis Sims, Psidium guajava L., and Stachytarpheta cayennensis (Rich.) Vahl. Among the interviewed people, 55.53% reported the use of plants to treat diarrhea, the most severe symptom of giardiasis. The results indicated 36 species used by this population for these problems. The use of leaves (72.50%) of a single plant (64.25%) collected from backyards and gardens (44.34%) and prepared by decoction were predominant. The majority of the interviewees (85.52%) attributed their cure to the use of plants. In the experimental tests, all extracts inhibited the growth of Giardia lamblia trophozoites in different intensities: A. occidentale and P. guajava extracts elicited a moderate activity (250 ≤ IC50 ≤ 500μg/ml), C. ambrosioides and S. cayennensis extracts evoked a high activity (100 ≤ IC50 ≤ 250μg/ml), and P. edulis extract showed very high activity (IC50 ≤ 100μg/ml). This study shows that an ethnopharmacological approach is useful in the selection of plant materials with potential giardicidal activity.