In vitro evaluation of copaiba oil as a kojic acid skin enhancer

Abstract

The capacity of copaíba oil to act as a skin penetration enhancer for the depigmenting agent kojic acid was evaluated using an in vitro diffusion system with static flux and shed rattlesnake skin membrane, Crotalus durissus terrificus, in saline solution at 34±2 °C as the fluid receptor. The quantities of kojic acid liberated into the fluid receptor were determined by spectrophotometry at 268 nm with intervals of one and a half hours. The membranes, pretreated with copaíba oil at 25% and 50% v/v, gave flux values of 8.0 and 12.7 µg/cm 2 /h, permeability values of 2.0 and 3.3 cm×10-4 /h, and promotion factors of 4.1 and 3.7, respectively. These results indicate that copaíba oil, at the two concentrations studied, has the capacity to promote penetration of kojic acid.Uniterms: Copaíba oil. Kojic acid. Skin penetration/ in vitro studies .UV Spectrophotometry.A propriedade do óleo de copaíba como agente promotor de penetração cutânea do despigmentante ácido kójico foi avaliada utilizando-se sistema de difusão in vitro com fluxo estático, membrana de pele da serpente cascavel -Crotalus durissus terrificus e solução salina a 34±2 °C como fluido receptor. As quantidades liberadas do ácido kójico no fluido receptor foram determinadas por espectrofotometria em 268 nm em intervalos de 1:30 h. As membranas pré-tratadas com óleo de copaíba a 25 e 50% v/v apresentaram valores de fluxo de 8,0 e 12,7 µg/cm 2 /h, permeabilidade de 2,0 e 3,3 cm×10-4 /h, e fatores de promoção de 4,1 e 3,7, respectivamente. Os resultados obtidos indicaram que o óleo de copaíba, nas duas concentrações estudadas, apresentou capacidade de promoção da penetração do ácido kójico. Unitermos: Óleo de copaíba. Ácido kójico. Penetração cutânea/ in vitro. Espectrofotometria UV. INTRODUCTIONHyper pigmentation of the skin can be caused by a range of factors such as aging, pregnancy, endocrine disturbances, hormonal treatment and sun exposure to varying degrees. Several substances are commonly employed as depigmentation agents in the manufacture of cosmetics used for the reduction of hyper pigmentation, one of these being kojic acid (Cabanes, Garcia-Carmona, 1994;Su, 1999;Nicoletti et al., 2002). Kojic acid (5-hydroxy-2-(hydroxymethyl)-4-pirone) is a depigmenting agent obtained from rice fermentation (Burdock et al., 2001) as a fungus metabolite from the genera Aspergillus and Penicillym, and acts by inhibiting tyrosinase activity (Cabanes, Garcia-Carmona 1994).In order to be effective, depigmenting agents incorporated in topical formulas must cross the stratum corneum to act on the more inner layers situated towards the basal lamina of the epidermis. To this end, the addition of other compounds with a greater capacity for skin penetration, also known as absorption promoters or "enhancers", can result in an increase in diffusion of substances by disorganizing the lamellas of the stratum corneum (Williams, Barry, 2004). The incorporation of these substances in formulations allows for the development of topical products with a lower concentration of active ingre...

Biological Activities and Cytotoxicity of Diterpenes from Copaifera spp. Oleoresins

“…Similarly, Oliveira et al [ 18 ] evaluated the in vitro effect of copaíba oleoresin with kojic acid, using a snakeskin model. It was observed that solutions containing copaíba oleoresin at 25% and 50% induced kojic acid penetration in 4.0 and 3.7, respectively.…”

Chemistry and Biological Activities of Terpenoids from Copaiba (Copaifera spp.) Oleoresins

“…Copaiba oleoresin is also used by the cosmetics and varnish industries [ 12 ]. Oliveira et al [ 67 ] observed that copaiba oleoresin has potential for use in topical formulation, as a stimulant agent for the absorption of hydrofilic bioactive substances. Despite the high volume of published works on copaiba oleoresin and its biological activities, there are few references that identifiy the compounds responsible for its biological activity.…”

Transdermal delivery of kojic acid from microemulgel

“…Other investigators recorded poor skin permeation for the same drug after application of aqueous solution (Oliveira et al, 2010). Incorporation of kojic acid in different microemulsion formulations significantly increased the transdermal drug flux compared with the saturated aqueous control (Table 3).…”