Produção e avaliação de nanoemulsões contendo óleo essencial de Bahinia ungulata como alternativa no tratamento da doença de alzheimer

Abstract

The species Bauhinia ungulata belongs to the Fabaceae family, popularly known as pata-de-vaca, and is among the species used medicinally in Brazil, mainly in the treatment of diabetes. In this work, the objective was to study the interaction of the chemical constituents present in the essential oil of B. ungulata (OEBU), collected in the municipality of Boa Vista, Roraima, Legal Amazon, and their effects on the enzyme acetylcholinesterase (AChE), with emphasis on the treatment of Alzheimer's. The qualitative and quantitative aspects by gas chromatography (GC-MS and GC-DIC) of the chemical constituents of OEBU were also evaluated, as well as 1H NMR analyses, molecular docking, in silico toxicity prediction, enrichment analysis and prediction of biological interaction targets, determination of antioxidant activity, such as total antioxidant activity (CAT), free radical scavenging (DPPH), reducing power and Fe2+ chelation. In vivo biological activities were performed using the wild strain N2 of the model organism Caenorhabditis elegans (C. elegans), which were subjected to survival, pharyngeal beating and AChE enzyme inhibition tests. Chromatographic analysis revealed 25 components, the major ones being α-bisabolol (27.2%), β-caryophyllene (12.5%), epi-γ-eudesmol (13.6%), α-humulene (4.5%), caryophyllene oxide (4.3%), and γ-muurolene (3.4%). In in vitro tests to evaluate the inhibitory effect of the AChE enzyme, the essential oil showed 100% inhibition. The major volatile component α-Bisabolol showed the highest chemical shift in the 1H NMR spectrum. In the antioxidant activity tests, OEBU presented a CAT value at a concentration of 0.1 mg.mL-1 of approximately 618.79 mg of ascorbic acid equivalent, at concentrations of 0.25 mg.mL-1 and 5 mg.mL-1 it presented a free radical scavenging capacity of around 43% and 65% respectively. OEBU presented a Fe2+ chelating capacity at the concentrations tested, has around 96% of total phenols and a reducing power of around 77% at a concentration of 0.5 mg.mL-1. It did not present a significant difference in relation to the control group in toxicity to C. elegans at the concentrations tested (0.0125 - 0.75 mg.mL-1). In the assay evaluating OEBU in relation to the pharyngeal beating of C. elegans, there was a reduction in the worm's feeding rate, which may indicate the inhibition of AChE, which was observed in the AChE inhibition assay using the nematode of up to 74.45% at a concentration of 0.025 mg.mL-1. The results of this work showed that OEBU acted as an inhibitor of the AChE enzyme in both in vitro and in vivo assays, as well as presenting oxidative activity. The formulations obtained from OEBU presented significant differences in relation to the surfactants DMSO and TW80, and can be used in the treatment of Alzheimer's disease in the form of non-emulsion.