1. Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraíba, Cx. Postal 5009, 58051-970, João Pessoa, PB, Brazil, Universidade Estadual do Norte Fluminense, 28015-620, Campos, RJ, Brazil, and Phytochemistry Research Laboratories, Department of Pharmaceutical Sciences, University of Strathclyde, 204 George Street, Glasgow G1 1XW, Scotland, U.K.