Eugenia neonitida Sobral and Eugenia rotundifolia Casar. (Myrtaceae) essential oils: composition, seasonality influence, antioxidant activity and leaf histochemistry

Abstract

The seasonality influence on the essential oil composition of trimestrially collected fresh leaves of Eugenia neonitida Sobral and Eugenia rotundifolia Casar. (Myrtaceae) was investigated, as well as the antioxidant activity of dried leaves essential oils, and the leaf histochemistry. Eugenia neonitida essential oil major compounds were bicyclogermacrene, germacrene D, and β-caryophyllene. Eugenia rotundifolia major compounds were α-pinene, β-pinene, and β-caryophyllene. The essential oils of both species were mainly composed by cyclic hydrocarbons and alcohols; sesquiterpenes in E. neonitida and monoterpenes in E. rotundifolia. Precipitation appears to influence both species essential oils composition. Essential oils from dried leaves exhibited weak antioxidant activities. Both species have presented secretory cavities filled with a complex solution of essential oils and other lipid classes, according to histochemical tests.