Caracterização da atividade antioxidante in vitro e toxicidade in vivo do cerume da abelha sem ferrão Tetragonisca fiebrigi (Apidae, Meliponini)

Abstract

Reactive oxygen species (ROS) and nitrogen (RNS) are normally produced in our body and, at low concentrations, play important physiological functions. However, its excess can damage biomolecules and contribute to the development of diseases. Our body has an endogenous antioxidant defense system capable of fighting these reactive species. In addition to acting synergistically with exogenous antioxidant sources, for example, from natural products, to inhibit oxidative damage and maintain redox homeostasis. In this context, the present study aimed to evaluate the antioxidant potential and toxicity of the cerumen of the stingless bee Tetragonisca fiebrigi, popularly known as Jataí. To determine the antioxidant capacity of the ethanolic extract of T. fiebrigi cerumen (EECT), in vitro assays were performed, using the free radicals 2,2-diphenyl-1-picryl-hydrazyl (DPPH• ) and 2,2'-azinobis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS•+). Tests were also carried out to evaluate the extract's ability to inhibit oxidative hemolysis and lipid peroxidation in human erythrocytes. To assess the toxicity of EECT, the animal model Caenorhabditis elegans, wild line N2 was used. As a result, we observed that EECT is able to neutralize DPPH• and ABTS•+ radicals in a concentration-dependent manner, the EECT was able to inhibit 49,87 % of DPPH• radicals, at a concentration of 3.000 µg/mL, and 78,45 % of ABTS•+ radicals, at a concentration of 2.000 µg/mL. In addition, the extract inhibited the oxidative hemolysis of human erythrocytes and lipid peroxidation, induced by AAPH, and it was observed that the EECT was able to inhibit 47,33 % of the hemolysis, at a concentration of 125 µg/mL after 240 min of incubation, in addition to inhibiting 41,35 % of lipid peroxidation, at a concentration of 100 µg/mL after 120 min of incubation. It was also possible to observe that the extract did not prove to be toxic to the C. elegans organism at the evaluated concentrations and time. The results obtained serve as a basis for the development of further studies or even of products containing the cerumen, which contributes to the promotion of knowledge and conservation of the stingless bee species Tetragonisca fiebrigi.