Abstract
The essential oils obtained from leaves of Eugenia brasiliensis, E. involucrata, E. jambolana, Psidium guajava and P. widgrenianum (Myrtaceae) were extracted by steam distillation and analyzed by GC/MS and correlation of Retention Indices. The volatile constituents were assayed for their activity as anti-inflammatory agents in the zymosan and lipopolysaccharide (LPS)- induced inflammatory models. Pre-treatment of mice with any of the oils at up to 100 mg/Kg as liposomes, p. o. had no inhibitory effect on leukocyte accumulation or protein leakage in zymosan-induced-pleurisy. E. jambolana was however effective in inhibiting total leukocyte (up to 56% at 200 mg/Kg) and eosinophil migration in LPS-induced pleurisy (up to 74% at 100 mg/Kg), but no dose-response correlation was observed. P. widgrenianum showed inhibitory effect only on eosinophil migration (up to 70% at 100 mg/Kg). Both EJ and PW were also assayed for ability to inhibit in vitro nitric oxide production. EJ inhibited NO production potently (up to 100%) and in a dosedependent manner, whereas PW showed only an effect moderate (51%), when tested below the cytotoxic dose (25 μg/well). Chromatographic profiles of the essential oils showed the predominance of sesquiterpenes in oils of E. brasiliensis, E. involucrata and P. guajava, whereas monoterpenes were more important in P. widgrenianum and predominant in E. jambolana.