title: Antioxidant Effect of Nanoemulsions Containing Extract of Achyrocline satureioides (Lam) D.C.-Asteraceae.
abstract: Ethanolic extracts of Achyrocline satureioides have pronounced antioxidant activity mainly due to the presence of the flavonoid quercetin. However, direct topical application of the extract is not possible due to the presence of high amounts of ethanol. In this sense, nanoemulsions arise as an alternative for topical formulation associating molecules with limited aqueous solubility. This article describes the development of topical nanoemulsions containing either A. satureioides extract or one of its most abundant flavonoid, quercetin. Nanoemulsions composed of octyldodecanol, egg lecithin, water and extract (NEE), or quercetin (NEQ) were prepared by spontaneous emulsification. This process led to monodisperse nanoemulsions presenting a mean droplet size of approximately 200-300 nm, negative zeta potential, and high association efficiency. A study of quercetin skin retention using porcine skin which was performed using a Franz diffusion cell revealed a higher accumulation of quercetin in skin for NEE when compared to NEQ. Finally, the antioxidant activity of formulations was measured by thiobarbituric acid-reactive species and the APPH model. A lower lipoperoxidation for the extract in respect to quercetin solution was observed. However, no difference between NEQ and NEE lipoperoxidation could be seen. The protection against lipoperoxidation by the formulations was also measured in the skin, where lower formation of reactive species was observed after treatment with NEE. In conclusion, this study shows the formulation effect on the physicochemical properties of nanoemulsions as well as on the skin retention and antioxidant activity of quercetin.
authors.affiliation: Programa de Pós-graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Ipiranga 2752, 90610-000, Porto Alegre, RS, Brazil.
authors.forename: Giovanni Konat
authors.initials: GK
authors.lastname: Zorzi
authors.affiliation: Programa de Pós-graduação em Bioquímica, Universidade Federal do Rio Grande do Sul (UFRGS), R. Ramiro Barcelos 2600, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Caregnato
authors.affiliation: Programa de Pós-graduação em Bioquímica, Universidade Federal do Rio Grande do Sul (UFRGS), R. Ramiro Barcelos 2600, 90035-003, Porto Alegre, RS, Brazil.
authors.forename: José Cláudio Fonseca
authors.initials: JC
authors.lastname: Moreira
authors.affiliation: Programa de Pós-graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Ipiranga 2752, 90610-000, Porto Alegre, RS, Brazil.
authors.forename: Helder Ferreira
authors.initials: HF
authors.lastname: Teixeira
authors.affiliation: Programa de Pós-graduação em Produtos Bioativos e Biociências, Universidade Federal do Rio de Janeiro, Av. Aluisio da Silva Gomes 50, 27930-560, Macaé, Brazil. ffelsc@yahoo.com.br.
authors.forename: Edison Luis Santana
authors.initials: EL
authors.lastname: Carvalho
mesh_terms: D036921:Achyrocline / Q000737:chemistry*; D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D019659:Asteraceae / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004655:Emulsions / Q000737:chemistry / Q000494:pharmacology*; D005233:Fatty Alcohols / Q000737:chemistry; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D011794:Quercetin / Q000737:chemistry / Q000494:pharmacology; D012867:Skin / Q000378:metabolism; D012869:Skin Absorption / Q000187:drug effects; D012995:Solubility; D013552:Swine
chemical_list: D000975:Antioxidants; D004655:Emulsions; D005233:Fatty Alcohols; D005419:Flavonoids; D010936:Plant Extracts; C456972:octyl dodecanol; D011794:Quercetin
keywords: Achyrocline satureioides; extractive solution; nanoemulsion; quercetin; topical antioxidant