Desenvolvimento e caracterização de nanoemulsão à base de óleo de sucupira (Pterodon spp.), avaliação de sua toxicidade e bioatividade in vitro

• Autor(a) principal: Pacheco, Maiulle Teixeira
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/8731
• topic: Fotoenvelhecimento; Óleo de sucupira; Estresse oxidativo; Nanoemulsãoestabilidade; Photoaging; Sucupira oil nanoemulsion; Stability; Oxidative stress; CIENCIAS DA SAUDE::FARMACIA

The effects of ultraviolet radiation on a skin have been extensively studied. Chronic exposure to solar radiation has been considered to be the major cause of skin cancer and photoaging. As bioactive molecules derived from natural products have been researched for the development of sunscreens combining ability to absorb UV light with potential antioxidant activity. Sucupira oil (Pterodon spp.) is cited in the literature for its anti-inflammatory, anti-nociceptive and antioxidante activities, among others. This research aimed to develop an oil-based sucupira nanoemulsion using a method of high energy emulsification, and to evaluate the influence of components and parameters related to the method in the stability and size of the droplets of nanoemulsions. Also, to assess its safety and effectiveness for in vitro methods. The HLB value, the association of surfactants, the ratios between the aqueous / oil phases and surfactants, operating conditions, and number of cycles in the homogenizer will influence the stability, size and size distribution of the droplets exhibited by the nanoemulsions. The nanoemulsions show pH between 4.0 and 5.0, average diameter of the droplets around 150nm and polydispersity index lower than 0.2 (indicating narrow size distribution) after being submitted to two cycles in the high pressure homogenizer at a pressure of 500 bar. Formulations containing 10% oil, 3 or 4% surfactant and 86% water with HLB values between 11 and 13 were the nanoemulsions presenting stability at all temperatures examined for a 90-day study period. NE presented IC50 of 20 μg of oil/mL on a human keratinocyte cell line (HaCat). NE did not exhibit photoprotective activity by inhibition of COX-2 and nuclear factor NFκB. However, it showed a protective effect against oxidative stress and the reduction of proinflammatory cytokines (IL-6 and IL-8) induced by UVA. The results obtained suggest that sucupira oil nanoemulsion is a potentially candidate for photoprotection by interfering with events initiated after UV exposure at keratinocytes.