In Vitro Cytotoxic Potential of Essential Oils of Eucalyptus benthamii and Its Related Terpenes on Tumor Cell Lines.

Eucalyptus L. is traditionally used for many medicinal purposes. In particular, some Eucalyptus species have currently shown cytotoxic properties. Local Brazilian communities have used leaves of E. benthamii as a herbal remedy for various diseases, including cancer. Considering the lack of available data for supporting this cytotoxic effect, the goal of this paper was to study the in vitro cytotoxic potential of the essential oils from young and adult leaves of E. benthamii and some related terpenes (α-pinene, terpinen-4-ol, and γ-terpinene) on Jurkat, J774A.1 and HeLa cells lines. Regarding the cytotoxic activity based on MTT assay, the essential oils showed improved results than α-pinene and γ-terpinene, particularly for Jurkat and HeLa cell lines. Terpinen-4-ol revealed a cytotoxic effect against Jurkat cells similar to that observed for volatile oils. The results of LDH activity indicated that cytotoxic activity of samples against Jurkat cells probably involved cell death by apoptosis. The decrease of cell DNA content was demonstrated due to inhibition of Jurkat cells proliferation by samples as a result of cytotoxicity. In general, the essential oils from young and adult leaves of E. benthamii presented cytotoxicity against the investigated tumor cell lines which confirms their antitumor potential.

Anatomia foliar de Corymbia calophylla (Lindl.) K.D.Hill & L.A.S. Johnson, Myrtaceae / Leaf anatomy of Corymbia calophylla (Lindl.) K.D. Hill e L.A.S. Johnson (Myrtaceae)

Corymbia pertence à família Myrtaceae e envolve mais de 100 espécies arbóreas. Particularmente, a espécie Corymbia calophylla (Lindl.) K.D.Hill & L.A.S. Johnson é um dos taxa transferidos de Eucalyptus para Corymbia, com utilização para a fabricação de mobiliário requintado e para o tratamento de disfunções digestivas, segundo a medicina tradicional australiana. O presente trabalho teve por objetivo avaliar as características anatômicas da folha de C. calophylla, a partir de espécimes coletados na Embrapa Florestas (Colombo-PR, Brasil). As análises anatômicas foram conduzidas a partir dos métodos usuais de microscopia fotônica e microscopia eletrônica. A anatomia foliar revelou a presença de estômatos anomocíticos na face abaxial da folha, mesofilo dorsiventral e nervura mediana com cavidades secretoras inseridas no sistema vascular. Em secção transversal, o pecíolo apresentou formato plano-convexo. Na estrutura anatômica do limbo foliar, da nervura mediana e do pecíolo foram observadas cavidades secretoras contendo material de natureza lipofílica, além de idioblastos de conteúdo fenólico. Alguns idioblastos contendo drusas de oxalato de cálcio foram também observados no parênquima da nervura mediana de C. calophylla.

Corymbia, a genus of Myrtaceae, shows more than 100 tree species. In particular, Corymbia calophylla (Lindl.) K.D.Hill & L.A.S. Johnson is one of the taxa changed from Eucalyptus to Corymbia. C. calophylla has been used for fine furniture and for treating digestive upsets according to the Australian traditional medicine. The goal of this paper was to study the anatomical data of leaves from C. calophylla. The botanical material was collected from Embrapa Forest (Colombo-PR, Brazil). The anatomical analyses were performed by the usual light and scanning microtechniques. Anomocytic stomata were observed on the abaxial surface. The foliar blade showed dorsiventral mesophyll. Midrib having secretory cavities included on the vascular system was seen. In transection, a plane-convex petiole was found. Secretory cavities with oil content were verified in the anatomical structures of the foliar blade, midrib and petiole, as well as idioblasts with phenolic substances. Some calcium oxalate druses were observed in parenchymatous tissue of the midrib of C. calophylla.