Desenvolvimento de sistemas emulsionados contendo óleo de Castanha-do-Brasil (Bertholletia excelsa)

Abstract

Bertholletia excelsa tree that produces the Brazil nuts is present throughout the Amazon. Its seeds contain oil composed, mostly, of fatty acids, especially linoleic, oleic and palmitic acids, which are able to act in transepidermal barrier. It also presents other substances such as proteins, vitamins and minerals, which are functional molecules that act in processes that promote skin hydration. In this sense, this study aims to verify the feasibility of obtaining three emulsion systems (emulsion, microemulsion and nanoemulsion) using Brazil nuts oil as oil phase, which were subjected to physical and chemical tests to find what the system will present greater feasibility of obtaining and stability. The results showed that the oil obtained by cold pressing has quality for research purposes. A critical HLB value of 4.7 was found; indicating that proper surfactant to emulsify the Brazil nuts oil should have this value or values close. Stable emulsions using the surfactant span were obtained 60® (HLB = 4,7) and it was found that the concentration of surfactant and Brazil nuts oil directly affect the physicochemical properties of the emulsions, except for the electrical conductivity which only the Span 60® exerted influence on that property. Nanoemulsions were obtained using high pressure homogenizer, ultra-turrax®, at speeds of 10,000 and 15,000 rpm, and pair of Span80® and Tween 80® surfactants in different proportions, it was found that both the speed of agitation and concentration of surfactants They interfered in the physicochemical characteristics of nanoemulsions, except the electrical conductivity in which only the stirring speed exerted influence on that property. Microemulsions using Span80® as surfactant were obtained; and 1,2-octenediol and 1,2- hexanediol as a co-surfactant. Microemulsions were stable after its preparation with macroscopic characteristics of microemulsion systems, their physicochemical characteristics such as viscosity, differed according to the co-surfactant used. Thus, emulsions were obtained, microemulsions and nanoemulsions using exclusively Brazil nuts oil as the oil phase, which may serve as vehicles for the incorporation of drugs and/or other active ingredients which contains in its composition a vegetable oil that combines values the forest promoting ecological and economic sustainability.