12The use of plants and their products for medical treatment is very common 13 procedure in Brazil, especially for treatment of diabetes. In fact, several plants can 14 demonstrate hypoglycemic effects in vitro assays. However, the use for human 15 treatment requires the knowledge of their toxicological properties. The aim of this study 16 was to evaluate the effect of protein extracts of Chrysobalanus icaco collected from 17 natural habitats and of Eugenia astringens acquired from the market of Rio de Janeiro 18 on the viability and migration of fibroblasts. E. astringens has a similar morphology as 19 C. icaco and it is sold as Chrysobalanus in a popular market in Rio de Janeiro. Being a 20 different plant, E. astringens expresses different proteins, and its protein extract has 21 proved to possess higher toxic properties than C. icaco does. Cytotoxicity assays 22 indicated that, as the protein extract concentration increases, fibroblast viability 23 decreases. Only the E. astringens extract displayed cytotoxicity at all concentrations, in 24 addition to reduced fibroblast migration. The results obtained in this study demonstrates 25 that it's necessary integrative policies for rational use of medicinal plants and their 26 commercialization, since the current use of medicinal plants may be inadequate and it is 27 of great importance for Public Health. 28