Desenvolvimento e avaliação da atividade antibacteriana de nanoemulsões de óleo de patauá (Oenocarpus bataua)

Abstract

Patauá vegetable oil is rich in fatty acids that are beneficial to health, as well as antioxidant and antibacterial properties, making it an attractive food-grade component. However, its chemical structure makes it unfeasible to use in food formulations, which makes it relevant to use nanoemulsions to overcome this challenge, promoting interaction and enabling better delivery mechanisms for bioactives and nutrients. The main objective of this work was to obtain and evaluate the antibacterial activity of patauá oil nanoemulsions. The oil was evaluated for its physicochemical properties and functional indices including iodine index, saponification, density, oxidative capacity, atherogenicity (AI), thrombogenicity (IT) and hypocholesterolemic/hypercholesterolemic ratio (H/H), followed by the composition of the lipid profile by GC-MS and the nanoemulsions, prepared by the low energy method, were characterized for size, PDI and zeta potential values. Finally, both samples were evaluated for their bacterial activity using nine strains standardized by the well diffusion method. Patauá oil showed iodine, saponification, density and oxidative capacity values of 64.84, 200.7, 0.912, 0.992, respectively, while its functionalities showed 0.25 for AI, 0.78 for IT and 3.93 for H/H. The lipid profile showed a majority of unsaturated fatty acids such as oleic acid and triglycerides such as triolein. The nanoemulsions had a size of 54.68 and 102.4 nm, a PDI of 0.191 and 0.215, and a zeta potential of -8.91 and -14.3. In terms of antibacterial activity, both the patauá oil and the surfactant did not show an inhibitory zone in any of the wells; however, both nanoemulsions showed activity against three gram-negative bacteria such as Aeromonas hydrophyla, Proteus vulgaris and Pseudomonas aeroginosa, and one gram-positive bacteria such as Streptococcus equi. The other bacteria analyzed did not show inhibition values in any of the samples. In short, patauá oil proved to be an excellent component for application in food-grade products due to its nutritional and bioactive potential, as well as a source of bacterial inhibition.