de Freitas Zaida Maria Faria, dos Santos Elisabete Pereira, da Rocha João Ferreira, Dellamora-Ortiz Gisela Maria, Gonçalves José Carlos Saraiva
Departamento de Medicamentos, Universidade Federal do Rio de Janeiro, CCS bloco K, 2 andar, sala 50, Ilha do Fundão, CEP 21941-590, Rio de Janeiro, Brazil.
Eur J Pharm Sci. 2005 May;25(1):67-72. doi: 10.1016/j.ejps.2005.01.018.
Glyceryl esters of p-methoxycinnamic acid, 1,3-dipalmitoyl-2-p-methoxycinnamoyl-1,2,3-propanetriol and 1,3-dioctanoyl-2-p-methoxycinnamoyl-1,2,3-propanetriol were synthesised in an attempt to increase substantivity and decrease eventual undesirable effects of sunscreens of this class. To assess if the glyceryl esters could present a higher stability towards hydrolysis by lipases in the stratum corneum, hydrolysis rates were determined in vitro using a commercial fungal lipase from Rhizomucor miehei. Results presented herein show that the glyceryl esters have similar lambda(max) and epsilon values to sunscreens of the cinnamate class. The ester 1,3-dipalmitoyl-2-p-methoxycinnamoyl-1,2,3-propanetriol presented a 2.8 times lower hydrolysis rate by lipase, in vitro, than the commercial sunscreen 2-ethylhexyl-p-methoxycinnamate (alkyl ester). This finding suggests that this triacylglycerol can possibly have a longer retention time in the skin and consequently promote a more intense and effective antisolar action than the commercial sunscreen.
对甲氧基肉桂酸甘油酯、1,3 - 二棕榈酰 - 2 - 对甲氧基肉桂酰 - 1,2,3 - 丙三醇和1,3 - 二辛酰 - 2 - 对甲氧基肉桂酰 - 1,2,3 - 丙三醇被合成，旨在提高此类防晒剂的亲肤性并减少最终可能出现的不良影响。为评估这些甘油酯对角质层中脂肪酶水解作用的稳定性是否更高，使用来自米黑根毛霉的市售真菌脂肪酶在体外测定了水解速率。本文给出的结果表明，这些甘油酯与肉桂酸酯类防晒剂具有相似的最大吸收波长（λ(max)）和摩尔吸光系数（ε）值。酯类1,3 - 二棕榈酰 - 2 - 对甲氧基肉桂酰 - 1,2,3 - 丙三醇在体外经脂肪酶催化的水解速率比市售防晒剂2 - 乙基己基 - 对甲氧基肉桂酸酯（烷基酯）低2.8倍。这一发现表明，这种三酰甘油在皮肤中的保留时间可能更长，因此与市售防晒剂相比，能促进更强且更有效的防晒作用。
