Perfil fitoquímico e avaliação dos principais efeitos biológicos e imunológicos In Vitro da Euphorbia tirucalli L.

Abstract

Today we can easily find the most diverse kind of information about a particular medicinal plant, but without scientific basis, making their use a potential risk to health. Overall, the findings on the safety and efficacy are based on precarious evaluations and popular use. There is a need for qualified professionals to access, critical analyze and assign such information in a way that it could be easily understood, not only by health professionals, but also by the users of these products. One example of these plants used in popular medicine, but without scientific evidence, is Euphorbia tirucalli L., popularly known as Dog-Stick, Pencil tree, or more commonly as Aveloz. This plant has been used for the treatment of many diseases, such as microbial diseases, immunossupression problems, and even in the cancer treatment. However, some works reveal precisely the opposite, namely that the latex of Euphorbia tirucalli can cause immunosuppression, and often is associated to the appearance of Burkitt's Lymphoma, a type of cancer. Lupeol was isolated and identificated from hexane fraction by GC-MS for the first time for the plant, among other 3 hydrocarbons, 7 long chain fat acids, 2 steroids, and 3 compounds of the vegetal metabolism. A preliminary phytochemistry screening allowed to the visualization of the principal groups in the plant. Polyphenols and condensed tannins contents were determined in the crude extract and fractions. Ethyl ether and ethyl acetate fractions showed the greatest antioxidant activity in the DPPH test. Antimicrobial activity was observed mainly against Candida albicans, Candida glabrata and Saccharomyces cereviseae, as well as for the opportunist algae Prototheca zopfii. A preliminary study of toxicity using Artemia saline and acute oral toxicity in mice, indicate the plant as low toxicity. The latex of the E. tirucalli, even in small doses (1%) can cause in vitro inhibition over the human Acetylcholinesterase enzyme. A prominent in vitro inhibitory activity over human platelets aggregation was also observed. The effects of the extract of the plant over the blood cells in a culture medium using ex-vivo blood samples of male Wistar rats were evaluated. The results demonstrated that the extract caused thrombocytopenia, leucopenia and lymphopenia.