Desenvolvimento de filmes biopoliméricos que incorporam o óleo essencial de Lithraea brasiliensis Marchand: avaliação das propriedades físico-químicas, atividade leishmanicida e citotoxicidade.

Abstract

Biopolymers are chemical compounds produced by living beings or raw materials from renewable energy sources, which have the ability to form gels and viscous solutions in an aqueous medium. Due to their physicochemical properties, as well as their biocompatible and biodegradable character, these types of materials are widely used in the pharmaceutical industry. The objective of this work was to prepare self-supporting carboxymethylcellulose films combined with the polysaccharide sodium alginate or the zein protein, which were used as biopolymeric matrices for the essential oil of Lithraea brasiliensis. The prepared films were characterized by vibrational spectroscopy in the infrared region (FTIR), scanning electron microscopy (SEM),TG/DTG and DSC thermal analysis, as well as the transmission rates of water vapors were also investigated. After chemical characterization, in vitro cytotoxicity tests were performed using sheep erythrocytes and RAW cells. As for the leishmanicidal activity in promastigotes of Leishmania amazonensis, the test was performed using the MTT method (3-(4,5- dimethyithiazol2-yl) -2,5-diphenyltetrazolium bromide). The synthesized biofilms indicated a better thermal and chemical stability of the essential oil once encapsulated in the biopolymeric matrix compared to the pure oil, ensuring good retention of the essential oil constituents, being highly promising for pharmacological application, while the cytotoxic assay in erythrocytes from sheep and in RAW cells, expressed correlation of results, in which the treatment with the synthesized films did not present relevant toxicity, being characterized the system as dose dependent for RAW cells. When analyzing the films on the promastigotes forms of Leishmania amazonensis, it was concluded that there was toxicity in all tested samples. Therefore, biofilms arouse interest, since they are capable of inhibiting and interfering with the course of leishmaniasis. These results direct us to future investigations, since there are few studies related to this technology of the material and the characteristics of the essential oil.